{"id":2055,"date":"2017-04-16T20:27:31","date_gmt":"2017-04-16T18:27:31","guid":{"rendered":"http:\/\/www.astrobobo.net\/?p=2055"},"modified":"2020-01-31T08:22:05","modified_gmt":"2020-01-31T06:22:05","slug":"astrofotografija-kroz-teleskop","status":"publish","type":"post","link":"http:\/\/www.astrobobo.net\/?p=2055","title":{"rendered":"Astrofotografija kroz teleskop"},"content":{"rendered":"<p>Naj\u010de\u0161\u0107e pitanje koje se postavlja prilikom kupovine teleskopa je upravo kako napraviti fotografiju kroz teleskop. Fotografije \u0161arenih maglica i udaljenih galaksija mamac su za sve koji vole astronomiju. Odmah u startu morate znati da je <span style=\"text-decoration: underline;\"><strong>astrofotografija kroz teleskop vrlo zahtjevna<\/strong><\/span>. Odabir teleskopa, monta\u017ee i aparata za fotkanje klju\u010dan je za uspje\u0161nu astrofotografiju. Zahtjevi su znatno druk\u010diji od teleskopa za vizualno promatranje. Ako vam astrofotografija nije klju\u010dna, teleskop za vizualno promatranje \u0107e vas znatno manje ko\u0161tati uz puno ve\u0107u satisfakciju.<\/p>\n<p>Ukratko &#8211; <strong>ne, ne mo\u017eete fotografirati kroz teleskop iz du\u0107ana koji ko\u0161ta samo 3000 kn!<\/strong> OK, da budem precizniji &#8211; mo\u017ee se okinuti fotka Mjeseca, uz par trikova snimiti poneki detalj na planetima, napraviti snapshot mobitelom kroz okular, ali to je otprilike sve. Ako vam je to dovoljno, ok, ali za kvalitetne fotke potrebna je i kvalitetna oprema.<\/p>\n<p><strong>Astrofotografijom se vrlo uspje\u0161no mo\u017eete baviti i bez teleskopa<\/strong>. O tome vi\u0161e u sljede\u0107im tekstovima:<\/p>\n<ul>\n<li><a href=\"http:\/\/www.astrobobo.net\/?p=491\" target=\"_blank\" rel=\"noopener noreferrer\">Jednostavna astrofotografija (1)<\/a><\/li>\n<li><a href=\"http:\/\/www.astrobobo.net\/?p=514\" target=\"_blank\" rel=\"noopener noreferrer\">Jednostavna astrofotografija (2)<\/a><\/li>\n<\/ul>\n<p>Tako\u0111er preporu\u010dam i tekst o <a href=\"http:\/\/www.astrobobo.net\/?p=1677\" target=\"_blank\" rel=\"noopener noreferrer\">kupovini teleskopa kao poklon<\/a> budu\u0107i da sve u njemu napisano odgovara za bilo koji po\u010detni\u010dki teleskop.<\/p>\n<p><strong>Ovaj tekst nije step by step uputa kako napraviti astrofotografiju.<\/strong> Biti \u0107e opisane smjernice za opremu koja je potrebna za astrofotografiju kroz teleskop, na vama je da usavr\u0161ite metodu jednom kada opremu nabavite.<\/p>\n<div class=\"tiled-gallery type-rectangular tiled-gallery-unresized\" data-original-width=\"1240\" data-carousel-extra='{&quot;blog_id&quot;:1,&quot;permalink&quot;:&quot;http:\\\/\\\/www.astrobobo.net\\\/?p=2055&quot;,&quot;likes_blog_id&quot;:&quot;3412760&quot;}' itemscope itemtype=\"http:\/\/schema.org\/ImageGallery\" > <div class=\"gallery-row\" style=\"width: 1240px; height: 934px;\" data-original-width=\"1240\" data-original-height=\"934\" > <div class=\"gallery-group images-1\" style=\"width: 620px; height: 934px;\" data-original-width=\"620\" data-original-height=\"934\" > <div class=\"tiled-gallery-item tiled-gallery-item-large\" itemprop=\"associatedMedia\" itemscope itemtype=\"http:\/\/schema.org\/ImageObject\"> <a href=\"http:\/\/www.astrobobo.net\/?attachment_id=2057\" border=\"0\" itemprop=\"url\"> <meta itemprop=\"width\" content=\"616\"> <meta itemprop=\"height\" content=\"930\"> <img loading=\"lazy\" decoding=\"async\" class=\"\" data-attachment-id=\"2057\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_01.jpg\" data-orig-size=\"3264,4928\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;6.7&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;NIKON D5100&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;1314214134&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;24&quot;,&quot;iso&quot;:&quot;800&quot;,&quot;shutter_speed&quot;:&quot;0.0166666666667&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;1&quot;}\" data-image-title=\"Astrofoto_setup_01\" data-image-description=\"\" data-medium-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_01-199x300.jpg\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_01-678x1024.jpg\" src=\"https:\/\/i0.wp.com\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_01.jpg?w=616&#038;h=930\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_01.jpg 3264w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_01-132x200.jpg 132w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_01-199x300.jpg 199w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_01-768x1160.jpg 768w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_01-678x1024.jpg 678w\" width=\"616\" height=\"930\" loading=\"lazy\" data-original-width=\"616\" data-original-height=\"930\" itemprop=\"http:\/\/schema.org\/image\" title=\"Astrofoto_setup_01\" alt=\"Moj astrofotografski setup: Pentax 105 SDP, Celestron CGE, SBIG STL-11000M, laptop, eksterna baterija.\" style=\"width: 616px; height: 930px;\" \/> <\/a> <div class=\"tiled-gallery-caption\" itemprop=\"caption description\"> Moj astrofotografski setup: Pentax 105 SDP, Celestron CGE, SBIG STL-11000M, laptop, eksterna baterija. <\/div> <\/div> <\/div> <!-- close group --> <div class=\"gallery-group images-1\" style=\"width: 620px; height: 934px;\" data-original-width=\"620\" data-original-height=\"934\" > <div class=\"tiled-gallery-item tiled-gallery-item-large\" itemprop=\"associatedMedia\" itemscope itemtype=\"http:\/\/schema.org\/ImageObject\"> <a href=\"http:\/\/www.astrobobo.net\/?attachment_id=2058\" border=\"0\" itemprop=\"url\"> <meta itemprop=\"width\" content=\"616\"> <meta itemprop=\"height\" content=\"930\"> <img loading=\"lazy\" decoding=\"async\" class=\"\" data-attachment-id=\"2058\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_02.jpg\" data-orig-size=\"3106,4690\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;6.7&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;NIKON D5100&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;1314214268&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;32&quot;,&quot;iso&quot;:&quot;800&quot;,&quot;shutter_speed&quot;:&quot;0.0111111111111&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;1&quot;}\" data-image-title=\"Astrofoto_setup_02\" data-image-description=\"\" data-medium-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_02-199x300.jpg\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_02-678x1024.jpg\" src=\"https:\/\/i0.wp.com\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_02.jpg?w=616&#038;h=930\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_02.jpg 3106w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_02-132x200.jpg 132w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_02-199x300.jpg 199w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_02-768x1160.jpg 768w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_02-678x1024.jpg 678w\" width=\"616\" height=\"930\" loading=\"lazy\" data-original-width=\"616\" data-original-height=\"930\" itemprop=\"http:\/\/schema.org\/image\" title=\"Astrofoto_setup_02\" alt=\"Moj astrofotografski setup: Pentax 105 SDP, Celestron CGE, SBIG STL-11000M, laptop, eksterna baterija.\" style=\"width: 616px; height: 930px;\" \/> <\/a> <div class=\"tiled-gallery-caption\" itemprop=\"caption description\"> Moj astrofotografski setup: Pentax 105 SDP, Celestron CGE, SBIG STL-11000M, laptop, eksterna baterija. <\/div> <\/div> <\/div> <!-- close group --> <\/div> <!-- close row --> <\/div>\n<blockquote><p>Za snimanje maglica i galaksija nu\u017ene su <strong>duga\u010dke ekspozicije<\/strong>. Ovisno o teleskopu i aparatu ekspozicije se kre\u0107u <strong>od 2 pa \u010dak i do 30 minuta<\/strong>. Za to vrijeme <strong>slika koju projicira teleskop mora biti savr\u0161eno mirna<\/strong>. Dakle, zvijezde se <strong>doslovno ne smiju niti malo mrdnuti<\/strong> ina\u010de \u0107e fotografija biti mutna i upropa\u0161tena.<\/p><\/blockquote>\n<h2>Kako fotografirati kroz\u00a0 teleskop?<\/h2>\n<p><strong>Teleskop se zapravo koristi kao jedan veliki teleobjektiv.<\/strong> Umjesto okulara, direktno u fokuser se stavlja fotoaparat s kojega je skinut objektiv. Potreban je adapter (prsten) za odgovaraju\u0107i bajonet proizvo\u0111a\u010da (Canon, Nikon, Sony&#8230;) na T navoj, a zatim jo\u0161 jedan adapter s T navoja na 1.25&#8243; ili 2&#8243; promjer fokusera. Neki teleskopi na fokuseru ve\u0107 imaju T navoj, a mogu\u0107e je nabaviti i barlow le\u0107u s T navojem. Astronomske CCD\/CMOS kamere \u010desto imaju ve\u0107 1.25&#8243; ili 2&#8243; nastavak ili adapter.<\/p>\n<figure id=\"attachment_2075\" aria-describedby=\"caption-attachment-2075\" style=\"width: 1024px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter.jpg\"><img fetchpriority=\"high\" decoding=\"async\" data-attachment-id=\"2075\" data-permalink=\"http:\/\/www.astrobobo.net\/?attachment_id=2075\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter.jpg\" data-orig-size=\"1148,1148\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;1&quot;}\" data-image-title=\"Camera-Lens-T-Adapter\" data-image-description=\"\" data-image-caption=\"&lt;p&gt;T-prsten za DSLR i adapter za 1.25&amp;#8243; fokuser.&lt;\/p&gt;\n\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter-1024x1024.jpg\" class=\"wp-image-2075 size-large\" src=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter-1024x1024.jpg\" alt=\"\" width=\"1024\" height=\"1024\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter-1024x1024.jpg 1024w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter-200x200.jpg 200w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter-300x300.jpg 300w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter-768x768.jpg 768w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter-180x180.jpg 180w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter-600x600.jpg 600w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter-660x660.jpg 660w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Camera-Lens-T-Adapter.jpg 1148w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/a><figcaption id=\"caption-attachment-2075\" class=\"wp-caption-text\">T-prsten za DSLR i adapter za 1.25&#8243; fokuser.<\/figcaption><\/figure>\n<h2>Monta\u017ea<\/h2>\n<p><strong>Klju\u010dna stvar za astrofotografiju kroz teleskop je monta\u017ea.<\/strong> Ona je vrlo va\u017ena za dobru astrofotografiju i mora imati sljede\u0107e karakteristike:<\/p>\n<ul>\n<li>ekvatorijalna<\/li>\n<li>motorizirana<\/li>\n<li>\u010dvrsta i robustna<\/li>\n<\/ul>\n<p>Astrofotografija se mo\u017ee raditi jedino s <a href=\"https:\/\/en.wikipedia.org\/wiki\/Equatorial_mount\" target=\"_blank\" rel=\"noopener noreferrer\">ekvatorijalnom monta\u017eom<\/a>. Takva monta\u017ea ima os koja je usmjerena prema nebeskom polu. Motori pokre\u0107u monta\u017eu brzinom rotacije Zemlje, ali u suprotnom smjeru &#8211; na taj na\u010din objekt ostaje u vidnom polju kamere tijekom snimanja fotografije. Alt-azimutalne monta\u017ee mogu tako\u0111er biti motorizirane i pratiti objekt koji se promatra. Me\u0111utim, zvijezde se prividno gibaju u krugu oko nebeskog pola, dok alt-azimutalna monta\u017ea radi korekcije u smjeru gore-dolje (<strong>alt<\/strong>ituda) i lijevo-desno (<strong>az<\/strong>imut) u odnosu na tlo.<\/p>\n<figure id=\"attachment_1431\" aria-describedby=\"caption-attachment-1431\" style=\"width: 900px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2015\/07\/Metajna_Startrailscomet1.jpg\"><img decoding=\"async\" data-attachment-id=\"1431\" data-permalink=\"http:\/\/www.astrobobo.net\/?attachment_id=1431\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2015\/07\/Metajna_Startrailscomet1.jpg\" data-orig-size=\"900,601\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"Metajna_Startrailscomet\" data-image-description=\"\" data-image-caption=\"&lt;p&gt;Tragovi zvijezda oko nebeskog pola tijekom 45  minuta snimanja fotografije. Snimljeno blizu Metajne na Pagu.&lt;\/p&gt;\n\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2015\/07\/Metajna_Startrailscomet1.jpg\" class=\"size-full wp-image-1431\" src=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2015\/07\/Metajna_Startrailscomet1.jpg\" alt=\"\" width=\"900\" height=\"601\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2015\/07\/Metajna_Startrailscomet1.jpg 900w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2015\/07\/Metajna_Startrailscomet1-300x200.jpg 300w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2015\/07\/Metajna_Startrailscomet1-449x300.jpg 449w\" sizes=\"(max-width: 900px) 100vw, 900px\" \/><\/a><figcaption id=\"caption-attachment-1431\" class=\"wp-caption-text\">Tragovi zvijezda oko nebeskog pola tijekom 45 minuta snimanja fotografije. Snimljeno blizu Metajne na Pagu.<\/figcaption><\/figure>\n<p><strong>Monta\u017ea za astrofotografiju je \u010desto skuplja od samog teleskopa.<\/strong> Nosivost monta\u017ee koju navode proizvo\u0111a\u010di obi\u010dno se odnosi na vizualno promatranje. Za astrofotografiju se naj\u010de\u0161\u0107e ra\u010duna polovica te vrijednosti.<\/p>\n<p>Prije snimanja monta\u017ea se mora <strong>nivelirati<\/strong> i jako dobro <strong>usjeveriti<\/strong> (rektificirati). Za vizualna promatranja dovoljno je os otprilike usmjeriti prema nebeskom polu, no za astrofotografiju rektifikacija mora biti gotovo savr\u0161ena. U protivnom \u0107ete na fotografiji dobiti rotaciju vidnog polja &#8211; na rubovima \u0107e zvijezde opisivati maleni luk oko sredi\u0161ta fotografije. \u0160to je ve\u0107a \u017eari\u0161na duljina teleskopa, i rektifikacija mora biti bolja.<\/p>\n<p>Neke fork (vili\u010daste) monta\u017ee, popularne kod katadioptri\u010dkih teleskopa (schmidt-cassegrain) mogu se &#8220;pretvoriti&#8221; u ekvatorijalne upotrebom tzv. wedge-a. To je vrlo prakti\u010dno, no takav sustav je nestabilniji od alt-azimutalne postavke.<\/p>\n<figure id=\"attachment_1693\" aria-describedby=\"caption-attachment-1693\" style=\"width: 444px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/12\/eq-montaza_HR.png\"><img decoding=\"async\" data-attachment-id=\"1693\" data-permalink=\"http:\/\/www.astrobobo.net\/?attachment_id=1693\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/12\/eq-montaza_HR.png\" data-orig-size=\"444,386\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"eq-montaza_HR\" data-image-description=\"\" data-image-caption=\"&lt;p&gt;Ekvatorijalna monta\u017ea&lt;\/p&gt;\n\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/12\/eq-montaza_HR.png\" class=\"size-full wp-image-1693\" src=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/12\/eq-montaza_HR.png\" alt=\"\" width=\"444\" height=\"386\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/12\/eq-montaza_HR.png 444w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/12\/eq-montaza_HR-230x200.png 230w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/12\/eq-montaza_HR-345x300.png 345w\" sizes=\"(max-width: 444px) 100vw, 444px\" \/><\/a><figcaption id=\"caption-attachment-1693\" class=\"wp-caption-text\">Ekvatorijalna monta\u017ea<\/figcaption><\/figure>\n<p>Monta\u017ee za astrofotografiju mogu imati polarni tra\u017eioc. To je maleni tra\u017eioc naj\u010de\u0161\u0107e unutar rekstacenzijske osi (ona koja je usmjerena prema nebeskom polu) s ucrtanim zvijezdama za to\u010dno lociranje nebeskog pola. Na sjevernoj nebeskoj polutci nebeski pol se nalazi blizu Sjevernja\u010de, ali ipak je udaljen otprilike 3\/4 stupnja od zvijezde. Po\u017eeljno je da tra\u017eioc bude osvijetljen da bi se ucrtane oznake mogle vidjeti u mrklom mraku, ali mo\u017eete se sna\u0107i tako da sami osvijetlite nitni kri\u017e crvenom lampicom prilikom namje\u0161tanja monta\u017ee.<\/p>\n<h2>Usjeveravanje monta\u017ee<\/h2>\n<p>Ovaj dio mo\u017eete presko\u010diti ako vas samo zanima \u0161to je sve potrebno za astrofotografiju. Ipak nije lo\u0161e da se upoznate s metodom jer kod astrofotografije nije dovoljno samo &#8220;postaviti teleskop i po\u010deti fotkati&#8221;.<\/p>\n<p>Monta\u017ee za astrofotografiju naj\u010de\u0161\u0107e su kompjuterizirane i u svom programu imaju opciju za usjeveravanje. Nakon \u0161to monta\u017eu usmjerite prema nebeskom polu najbolje \u0161to mo\u017eete, na kontroleru monta\u017ee treba precizno kalibrirati go-to. Prvo je potrebno u kontroler upisati datum, vrijeme i to\u010dne geografske koordinate. Zatim, program u kontroleru ponudi nekoliko sjajnih zvijezda koje su trenutno vidljive, a na vama je da ih to\u010dno centrirate u vidnom polju okulara ili fotografije. Zato bi bilo dobro da <strong>znate imena sjajnih zvijezda<\/strong> ili sa sobom imate barem nekav atlas ili planetarij program na smartphoneu\/laptopu. Naime, ovisno o to\u010dnosti kojom ste napravili prethodne korake, program monta\u017ee poku\u0161ati \u0107e sam nani\u0161aniti zvijezde za kalibraciju, ali je sasvim mogu\u0107e da \u0107e prvu potpuno proma\u0161iti. Osim toga, ovisno o konfiguraciji terena Sjevernja\u010da mo\u017eda nije vidljiva na nebu! U centriranju \u0107e vam pomo\u0107i okular s nitnim kri\u017eem ili ozna\u010dena to\u010dna sredina vidnog polja fotoaparata.<\/p>\n<p>Postoje dodaci pomo\u0107i kojih se usjeveravanje mo\u017ee ubrzati ili automatizirati. To su <a href=\"http:\/\/www.recenzije.astrobobo.net\/qhy-polemaster\/\" target=\"_blank\" rel=\"noopener noreferrer\">QHY Polemaster<\/a>, <a href=\"https:\/\/www.celestron.com\/products\/starsense-autoalign\" target=\"_blank\" rel=\"noopener noreferrer\">Celestron StarSense<\/a> ili polar alignment opcija u <a href=\"http:\/\/www.sharpcap.co.uk\/sharpcap\/features\/polar-alignment\" target=\"_blank\" rel=\"noopener noreferrer\">SharpCap softveru<\/a>.<\/p>\n<p>Nakon go-to kalibracije program \u0107e vas uputiti da napravite korekcije na samoj monta\u017ei kako bi se precizno usjeverili. Zna\u010di, morati \u0107ete uz pomo\u0107 vijka malo pomaknuti osi\/nagib ekvatorijalne monta\u017ee. Metode proizvo\u0111a\u010da se mogu razlikovati, no naj\u010de\u0161\u0107e treba centrirati Sjevernja\u010du ili neku drugu zvijezdu u okularu. Dobre monta\u017ee uop\u0107e ne moraju uzeti u obzir Sjevernja\u010du za usjeveravanje.<\/p>\n<p>Ovaj korak se mora napraviti sa pa\u017enjom i mo\u017ee trajati 30-60 minuta.<\/p>\n<p><span style=\"text-decoration: underline;\">Ukratko:<\/span><\/p>\n<ul>\n<li>niveliranje trono\u0161ca<\/li>\n<li>grubo usjeveravanje<\/li>\n<li>unos datuma, vremena i geografskih koordinata<\/li>\n<li>go-to kalibracija<\/li>\n<li>korekcija ekvatorijalne glave za precizno usjeveravanje<\/li>\n<\/ul>\n<p>Ne, monta\u017ea ne mora imati go-to da bi se precizno usjeverilo. U tom slu\u010daju \u0107ete morati koristiti drift metodu i vrijeme za usjeveravanje se jako produljuje.<\/p>\n<p>Sad je mo\u017eda jasnije zbog \u010dega se mnogi astrofotografi odlu\u010duju na izgradnju vlastite male zvjezdarnice. Usjeveravanje se napravi samo jednom, vrlo precizno, i to je to!<\/p>\n<h2>Periodi\u010dka gre\u0161ka<\/h2>\n<p>Ne, nismo jo\u0161 gotovi s monta\u017eom \ud83d\ude42 Pa napisao sam ve\u0107 da je monta\u017ea najbitnija za astrofotografiju, zar ne? \ud83d\ude09<\/p>\n<p>OK, fino ste usjeverili monta\u017eu, stavite aparat, po\u010dnete snimati neki zanimljiv objekt poput ostatka supernove Messier 1 u Biku i nakon par minuta ekspozicije dobijete ovo:<\/p>\n<figure id=\"attachment_2683\" aria-describedby=\"caption-attachment-2683\" style=\"width: 1139px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/M1_periodic-error_kolor.jpg\"><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"2683\" data-permalink=\"http:\/\/www.astrobobo.net\/?attachment_id=2683\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/M1_periodic-error_kolor.jpg\" data-orig-size=\"1139,760\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;1&quot;}\" data-image-title=\"M1_periodic-error_kolor\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/M1_periodic-error_kolor-1024x683.jpg\" class=\"wp-image-2683 size-full\" src=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/M1_periodic-error_kolor.jpg\" alt=\"\" width=\"1139\" height=\"760\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/M1_periodic-error_kolor.jpg 1139w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/M1_periodic-error_kolor-300x200.jpg 300w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/M1_periodic-error_kolor-450x300.jpg 450w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/M1_periodic-error_kolor-768x512.jpg 768w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/M1_periodic-error_kolor-1024x683.jpg 1024w\" sizes=\"(max-width: 1139px) 100vw, 1139px\" \/><\/a><figcaption id=\"caption-attachment-2683\" class=\"wp-caption-text\">Periodi\u010dka gre\u0161ka za vrijeme 13 minuta ekspozicije maglice M1. Sitne to\u010dkice su hot pikseli.<\/figcaption><\/figure>\n<p><strong>Problem je sljede\u0107i:<\/strong> motore teleskopa pokre\u0107u pu\u017eni vijci koji nikada nisu savr\u0161eno izra\u0111eni ve\u0107 imaju neke malene gre\u0161ke. Prostim okom to ne primje\u0107ujemo, ali za astrofotografiju, kao \u0161to sam ve\u0107 napisao, zvijezde moraju stajati savr\u0161eno mirno tijekom ekspozicije. Te gre\u0161ke se sa svakim okretom vijka ponavljaju pa to zovemo <strong>periodi\u010dkom gre\u0161kom<\/strong>. Ona se manifestira tako da se cijelo vidno polje prividno giba prvo u jednom pa zatim u drugom smjeru i to se <em>periodi\u010dki<\/em> ponavlja.<\/p>\n<p>Teleskop, ovisno o \u017eari\u0161noj duljini i veli\u010dni piksela fotoaparata, ima neku mo\u0107 razlu\u010divanja. Razlu\u010divost ovisi i o stabilnosti atmosfere (<em>seeing<\/em>). Zbog gibanja zraka vidimo da zvijezde trepere &#8211; duga\u010dke ekspozicije \u0107e svjetlost zvijezde razvu\u0107i na nekoliko piksela. Seeing se ozna\u010dava u lu\u010dnim sekundama (oznaka <strong>&#8220;<\/strong>) koju prividno zauzima zvijezda. Tipi\u010dan seeing je 2-3&#8243;. S druge strane, periodi\u010dka gre\u0161ka mo\u017ee biti \u00b115&#8243; ili vi\u0161e u jednom smjeru!<\/p>\n<figure id=\"attachment_2062\" aria-describedby=\"caption-attachment-2062\" style=\"width: 640px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/periodic_error.gif\"><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"2062\" data-permalink=\"http:\/\/www.astrobobo.net\/?attachment_id=2062\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/periodic_error.gif\" data-orig-size=\"640,480\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"periodic_error\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/periodic_error.gif\" class=\"wp-image-2062 size-full\" src=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/periodic_error.gif\" alt=\"\" width=\"640\" height=\"480\" \/><\/a><figcaption id=\"caption-attachment-2062\" class=\"wp-caption-text\">Periodi\u010dka gre\u0161ka monta\u017ee. Lijevo je skala u lu\u010dnim sekundama.<\/figcaption><\/figure>\n<p><strong>Rje\u0161enje?<\/strong> Morate raditi korekcije brzine gibanja motora. Neke monta\u017ee imaju ugra\u0111enu PEC (periodic error correction) funkciju. \u010cak i sa PEC funkcijom ostaje neka mala gre\u0161ka, obi\u010dno oko 5&#8243;. Nekada dok se snimalo na film, to je bilo sasvim dovoljno, no za CCD kamere i digitalne fotoaparate se moraju raditi dodatne korekcije.<\/p>\n<h2>Autoguider<\/h2>\n<p>Jo\u0161 nismo do\u0161li ni do teleskopa, a ve\u0107 evo nove investicije u nizu opreme potrebne za astrofotografiju! Za potpunu eliminaciju gre\u0161aka u pra\u0107enju potreban je <strong>autoguider<\/strong>. Autoguider je dodatna kamera koja snima jednu jedinu zvijezdu u blizini objekta snimanja. \u010cim se zvijezda malo pomakne, autoguider \u0161alje signal monta\u017ei da malo uspori ili ubrza okretanje pu\u017enog vijka kako bi zvijezda ostala na istom mjestu.<\/p>\n<p>Da, morate imati <strong><span style=\"text-decoration: underline;\">dodatnu kameru<\/span><\/strong> za korekcije pra\u0107enja. To mo\u017ee biti specijalizirana autoguider kamera, kamera za snimanje planta, jeftina (starija?) CCD kamera ili \u010dak bolja web kamera. Ona mora biti dovoljno osjetljiva da otprilike u 2-3 sekunde ekspozicije mo\u017ee snimiti neku zvijezdu prema kojoj se rade korekcije. Ponekad se mo\u017ee dogoditi da u blizini \u017eeljenog objekta va\u0161 autoguider uop\u0107e ne mo\u017ee na\u0107i dovoljno sjajnu zvijezdu!<\/p>\n<p>Da bi autoguider kamera uop\u0107e mogla snimiti zvijezdu mora nekako do\u0107i do njene slike! Autoguider kamera se mo\u017ee staviti na dodatni teleskop ili \u010dak ja\u010di finder koji se stavlja paralelno uz primarni teleskop, a mo\u017ee se staviti i na off-axis guider.<\/p>\n<figure id=\"attachment_2064\" aria-describedby=\"caption-attachment-2064\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/off-axis_guider_03.jpeg\"><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"2064\" data-permalink=\"http:\/\/www.astrobobo.net\/?attachment_id=2064\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/off-axis_guider_03.jpeg\" data-orig-size=\"800,533\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"off-axis_guider_03\" data-image-description=\"\" data-image-caption=\"&lt;p&gt;Off-axis guider&lt;\/p&gt;\n\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/off-axis_guider_03.jpeg\" class=\"size-full wp-image-2064\" src=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/off-axis_guider_03.jpeg\" alt=\"\" width=\"800\" height=\"533\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/off-axis_guider_03.jpeg 800w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/off-axis_guider_03-300x200.jpeg 300w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/off-axis_guider_03-450x300.jpeg 450w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/off-axis_guider_03-768x512.jpeg 768w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><\/a><figcaption id=\"caption-attachment-2064\" class=\"wp-caption-text\">Off-axis guider<\/figcaption><\/figure>\n<p>Off-axis guider ima maleno zrcalo koje &#8220;krade&#8221; dio svjetlosti teleskopa i odbija ga sa strane gdje se stavlja kamera. Prednost je \u0161to se ne mora koristiti dodatni teleskop, ali je nedostatak ograni\u010denost u mogu\u0107nosti tra\u017eenja zvijezde za korekcije.<\/p>\n<p>Tvrtka <a href=\"http:\/\/diffractionlimited.com\/products\/cameras-accessories\/cameras\/\" target=\"_blank\" rel=\"noopener noreferrer\">SBIG (Santa Barbara Instrument Group)<\/a> koja proizvodi odli\u010dne astronomske CCD kamere ima patentirani dizajn gdje je paralelno s glavnim CCD \u010dipom postavljen manji \u010dip koji slu\u017ei za autoguiding.<\/p>\n<h2>Fotoaparat ili CCD\/CMOS kamera?<\/h2>\n<p>Kod astrofotografije se teleskop zapravo koristi kao veliki teleobjektiv. Zbog toga aparat za snimanje mora imati mogu\u0107nost skidanja objektiva ili se mo\u017ee koristiti specijalizirana CCD\/CMOS kamera za astrofotografiju. Moderni digitalni aparati rade jako dobre fotografije u slabim svjetlosnim uvjetima, no specijalizirane astro kamere su znatno bolje.<\/p>\n<p>Najve\u0107i neprijatelj snimanja tamnih objekata je <strong>digitalni \u0161um<\/strong>. Pikseli na \u010dipu &#8220;izmi\u0161ljaju&#8221; neke vrijednosti kada se poja\u010dava signal pa zato slika nikada nije potpuno crna, \u010dak i ako se fotografira sa poklopljenim teleskopom ili objektivom. \u0160um reagira na temperaturu okoli\u0161a &#8211; \u0161to je hladnije, manji je i digitalni \u0161um. U astrofotografiji je cilj svesti taj \u0161um na najmanju mogu\u0107u razinu da bi se \u017eeljeni objekt bolje snimio. Budu\u0107i da se \u0161um ne pojavljuje uvijek jednako na istom pikselu (hot pikseli su ne\u0161to drugo!) radi se po nekoliko snimki objekta koje se uprosje\u010duju kako bi se smanjio \u0161um.<\/p>\n<p>\u0160um se rje\u0161ava i snimanjem tzv. <strong>dark framea<\/strong> &#8211; ekspozicije je jednaka kao kada se snima \u017eeljeni objekt, ali se snima sa poklopcem na teleskopu! Na taj na\u010din snima se samo digitalni \u0161um koji se u obradi fotografije <strong>oduzima<\/strong> od glavne fotografije da bi se smanjio \u0161um.<\/p>\n<p>CCD\/CMOS kamere za astronomiju imaju brojne prednosti u odnosu na digitalne fotoaparate. Jedna od njih je upravo mogu\u0107nost hla\u0111enja \u010dipa. \u010cip se mo\u017ee hladiti 30\u00b0 od temperature okoli\u0161a, ponekad \u010dak i ni\u017ee! Sa svakih 5-7\u00b0 \u0161um se dvostruko smanjuje pa je to velika pogodnost.<\/p>\n<p>CCD\/CMOS kamere snimaju fotografije u tzv. FITS formatu. Datoteke imaju 32-bitnu dubinu boje, a to zna\u010di ogroman dinami\u010dki raspon, tj. broj nijansi koje ostaju zabilje\u017eene. Najbolji DSLR aparati imaju tek 14-bitni konverter.<\/p>\n<p>Mnoge maglice na nebu su od vodika koji im daje karakteristi\u010dnu crvenkastu boju. DSLR aparati ispred \u010dipa imaju filter koji blokira ve\u0107i dio emisijske linije vodika (h-alpha linija). Neke sjajnije maglice \u0107e se zabilje\u017eiti kao crvenkaste, ali mnoge \u0107e ostati blijedo sive. Postoje posebni DSLR-ovi koji propu\u0161taju ne\u0161to vi\u0161e crvene svjetlosti (Canon 60Da, Nikon D810A), ali i dalje \u0107e CCD kamere biti puno osjetljivije na taj dio spektra. Dobro rje\u0161enje je kupiti stariji i jeftiniji DSLR te ga modificirati micanjem filtera ispred \u010dipa. Treba staviti drugi filter koji blokira infracrvenu svjetlost jer su \u010dipovi osjetljivi na infracrveno.<\/p>\n<p>CCD kamere mogu biti <strong>monokromatske<\/strong> &#8211; bez bayer filtera na pikselima. Prednost je puno ve\u0107a osjetljivost jer bayer filteri propu\u0161taju samo 1\/3 dolazne svjetlosti. Astronomskim kamerama bayer filter nije potreban budu\u0107i da su objekti dubokog svemira &#8211; nepokretni. Da bi se dobila fotografija u boji snimaju se fotografije kroz R, G i B filter koje se zatim kombiniraju s L (luminance) kanalom snimljenim kroz prozirni filter koji propu\u0161ta cijeli spektar, a blokira samo infracrveno. Astronomske CCD kamere ponekad imaju integrirani kota\u010d sa filterima, naj\u010de\u0161\u0107e njih 5. Uz L (luminance, propu\u0161ta cijeli vidljivi spektar), R, G i B filtere dodaje se i h-alpha filter koji propu\u0161ta samo vodikovu liniju kako bi se dobile spektakularne fotografije vodikovih maglica.<\/p>\n<figure id=\"attachment_321\" aria-describedby=\"caption-attachment-321\" style=\"width: 1000px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2010\/11\/California_obrada2web.jpg\"><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"321\" data-permalink=\"http:\/\/www.astrobobo.net\/?attachment_id=321\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2010\/11\/California_obrada2web.jpg\" data-orig-size=\"1000,705\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;}\" data-image-title=\"California Nebula\" data-image-description=\"&lt;p&gt;Maglica California&lt;br \/&gt;\nPentax 105 SDP apo refraktor&lt;br \/&gt;\nCelestron CGE&lt;br \/&gt;\nSBIG STL-11000 CCD&lt;br \/&gt;\nHa:L:R:G:B 90:30:30:30:25 min (3h 25min total)&lt;br \/&gt;\nPetrova Gora, studeni 2010.&lt;br \/&gt;\nObrada Deep Sky Stacker + Photoshop&lt;\/p&gt;\n\" data-image-caption=\"&lt;p&gt;California Nebula&lt;\/p&gt;\n\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2010\/11\/California_obrada2web.jpg\" class=\"size-full wp-image-321\" src=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2010\/11\/California_obrada2web.jpg\" alt=\"\" width=\"1000\" height=\"705\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2010\/11\/California_obrada2web.jpg 1000w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2010\/11\/California_obrada2web-283x200.jpg 283w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2010\/11\/California_obrada2web-425x300.jpg 425w\" sizes=\"(max-width: 1000px) 100vw, 1000px\" \/><\/a><figcaption id=\"caption-attachment-321\" class=\"wp-caption-text\">California Nebula<\/figcaption><\/figure>\n<p>Neki astrofotografi se odlu\u010duju <strong>modificirati svoj DSLR<\/strong> stavljanjem peltier hla\u0111enja. Astronomske CCD kamere i dalje su u prednosti &#8211; hla\u0111enje je naj\u010de\u0161\u0107e regulirano, tj. dr\u017ei se konstatno na zadanoj temperaturi. Naime, da bi dark frameovi bili efikasni moraju se snimati na jednakoj temperaturi kao i fotografije objekta. Ovako se dark frame mo\u017ee snimiti kasnije, a no\u0107 cijela iskoristiti za astrofotografiju. Tako\u0111er, dark frameovi se mogu snimiti samo jednom i onda koristiti kasnije vi\u0161e puta!<\/p>\n<p>CCD kamere za astronomiju nemaju memorijske kartice pa je potrebno korisiti laptop za snimanje i korekcije pra\u0107enja.<\/p>\n<h2>Teleskop<\/h2>\n<p>Evo, napokon smo do\u0161li i do teleskopa! Naravno da on nije najmanje bitan, ali za astrofotografiju je vrlo va\u017eno shvatiti gore napisane probleme.<\/p>\n<p><strong>Nije svaki teleskop pogodan za astrofotografiju<\/strong>. Kao i kod objektiva za fotoaparate, va\u017ean je f-broj &#8211; \u0161to je manji to \u0107e i ekspozicije biti kra\u0107e.<\/p>\n<p>Najbitnije je, ipak, odabrati odgovaraju\u0107u vrstu teleskopa. <strong>Akromatski refraktori<\/strong> nisu pogodni za astrofotografiju upravo zbog kromatske aberacije. Zvijezde \u0107e imati ljubi\u010dasti halo i cijela fotografija \u0107e izgledati neo\u0161tro. Mnogi <strong>reflektori<\/strong> tako\u0111er nisu povoljni ako nisu osmi\u0161ljeni ba\u0161 za astrofotografiju. Moraju imati dovoljno veliko sekundarno zrcalo kako ne bi do\u0161lo do vinjetiranja, te fokuser niskog profila da slika na \u010dipu uop\u0107e mo\u017ee do\u0107i u fokus.<\/p>\n<p><strong>Katadiopter<\/strong>i poput maksutov-cassegrain teleskopa imaju veliki f-broj i maleni snop svjetlosti pa bi ekspozicije trebale biti ekstremno duga\u010dke i do\u0161lo bi do vinjetiranja. Neki maksutov-newton teleskopi su optimizirani za astrofotografiju. <strong>Schmidt-cassegrain<\/strong> teleskopi se pak \u010desto koriste u astrofotografiji iako su obi\u010dno f\/10. Ponekad se koriste u kombinaciji sa reduktorom fokusa. Katadiopteri su odli\u010dni za snimanje Mjeseca i planeta video kamerama.<\/p>\n<p>Teleskopi za astrofotografiju moraju biti <strong>jako dobro korigirani<\/strong> na opti\u010dke pogre\u0161ke. To naro\u010dito dolazi do izra\u017eaja na rubovima fotografije budu\u0107i da su moderni \u010dipovi sve ve\u0107ih formata. \u010cak i veliki, skupi teleskopi \u0107e profitirati od nekakvog korektora ili field flattenera. Nije ba\u0161 zgodno da uz svu tu silnu opremu na rubovima vidnog polja imate izdu\u017eene i deformirane zvijezde.<\/p>\n<p>Naj\u010de\u0161\u0107i teleskopi za astrofotografiju su <strong>mali apokromatski refraktori<\/strong>. Ne zahtjevaju masivne monta\u017ee, uz field flattener zvijezde su o\u0161tre do ruba, a\u00a0 f-broj je obi\u010dno povoljan. odli\u010dni su za snimanje maglica, no naj\u010de\u0161\u0107e nemaju dovoljnu \u017eari\u0161nu duljinu za ve\u0107inu galaksija. Uz nekoliko iznimaka, galaksije su obi\u010dno malene<\/p>\n<p><strong>Reflektori<\/strong>, newtoniani, tako\u0111er su popularan izbor. Obi\u010dno se koriste oni veliki, od 8&#8243; na vi\u0161e. Potrebne su im vrlo \u010dvrste monta\u017ee pa nije \u010dudno da teleskop nosi monta\u017ea koja je 3\u00d7 skuplja od njega! Reflektori na rubu vidnog polja imaju komu pa je za ve\u0107e \u010dipove tako\u0111er potreban korektor. Dobro je \u0161to imaju male f-brojeve, ne pate od kromatske aberacije, a velike \u017eari\u0161ne duljine i promjeri omigu\u0107uju detaljne fotografije galaksija.<\/p>\n<p>Postoje i razni drugi dizajni teleskopa, specijalizirani <strong>astrografi<\/strong> koji se koriste samo za astrofotografiju. To su razni richtey-chretieni (&#8220;kreteni&#8221;), brzi newtoniani sa ugra\u0111enim korektorima, brzi apo refraktori sa dodatnim le\u0107ama, korigirani schmidt-cassegraini itd. No o tome sada nije potrebno pisati &#8211; astrofotografi koji ih \u017eele sigurno ne\u0107e \u010ditati ovaj tekst \ud83d\ude09<\/p>\n<figure id=\"attachment_2068\" aria-describedby=\"caption-attachment-2068\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne.jpg\"><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"2068\" data-permalink=\"http:\/\/www.astrobobo.net\/?attachment_id=2068\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne.jpg\" data-orig-size=\"800,800\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne\" data-image-description=\"\" data-image-caption=\"&lt;p&gt;Astro Systeme Austria f\/3.8 newtonian sa Wynne korektorom.&lt;\/p&gt;\n\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne.jpg\" class=\"size-full wp-image-2068\" src=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne.jpg\" alt=\"\" width=\"800\" height=\"800\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne.jpg 800w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne-200x200.jpg 200w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne-300x300.jpg 300w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne-768x768.jpg 768w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne-180x180.jpg 180w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne-600x600.jpg 600w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/ASA-Telescope-10N-250-950-Astrograph-OTA-3-Wynne-660x660.jpg 660w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><\/a><figcaption id=\"caption-attachment-2068\" class=\"wp-caption-text\">Astro Systeme Austria f\/3.8 newtonian sa Wynne korektorom.<\/figcaption><\/figure>\n<h2>Za kraj<\/h2>\n<p>Jo\u0161 uvijek se \u017eelite baviti astrofotografijom? \ud83d\ude09 Nadam se da je sada jasnije zbog \u010dega astrofotografija kroz teleskop nije jednostavna da se samo stavi aparat i po\u010dne pucati fotke. Nemojte da vas ovaj tekst obeshrabri &#8211; napraviti astrofotku kroz teleskop veliko je zadovoljstvo. Ovo \u0161to ste pro\u010ditali shvatite kao pre\u010dac za odabir opreme za astrofotografiju.<\/p>\n<p>Uzmite u obzir da se <strong>sve ovdje napisano odnosi na fotografiranje objekata dubokog neba <span style=\"text-decoration: underline;\">kroz teleskop<\/span><\/strong>. Astrofotografija mo\u017ee biti puno vi\u0161e od toga! Kroz teleskop se mogu snimati fantasti\u010dni <strong>detalji na planetima<\/strong> bez kori\u0161tenja silne navedene opreme (autoguidera, korekcija&#8230;). Kao \u0161to sam napisao na po\u010detku, <strong>astrofotke su odli\u010dne \u010dak i bez teleskopa<\/strong>, a duga\u010dke ekspozicije mo\u017eete napraviti \u0161irokokutnim objektivima ili \u010dak manjim teleobjektivima uz pomo\u0107 <strong>barndoor monta\u017ee<\/strong> vlastite izrade ili <strong>komercijalnog trackera<\/strong>. Osim toga, fotoaparat mo\u017eete koristiti <strong>piggyback na svom teleskopu<\/strong> s ekvatorijalnom monta\u017eom!<\/p>\n<p>U svakom slu\u010daju, sretno s izborom, slobodno pi\u0161ite komentare i pitajte \u0161to vas zanima!<\/p>\n<div class=\"tiled-gallery type-rectangular tiled-gallery-unresized\" data-original-width=\"1240\" data-carousel-extra='{&quot;blog_id&quot;:1,&quot;permalink&quot;:&quot;http:\\\/\\\/www.astrobobo.net\\\/?p=2055&quot;,&quot;likes_blog_id&quot;:&quot;3412760&quot;}' itemscope itemtype=\"http:\/\/schema.org\/ImageGallery\" > <div class=\"gallery-row\" style=\"width: 1240px; height: 934px;\" data-original-width=\"1240\" data-original-height=\"934\" > <div class=\"gallery-group images-1\" style=\"width: 620px; height: 934px;\" data-original-width=\"620\" data-original-height=\"934\" > <div class=\"tiled-gallery-item tiled-gallery-item-large\" itemprop=\"associatedMedia\" itemscope itemtype=\"http:\/\/schema.org\/ImageObject\"> <a href=\"http:\/\/www.astrobobo.net\/?attachment_id=2056\" border=\"0\" itemprop=\"url\"> <meta itemprop=\"width\" content=\"616\"> <meta itemprop=\"height\" content=\"930\"> <img loading=\"lazy\" decoding=\"async\" class=\"\" data-attachment-id=\"2056\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_04.jpg\" data-orig-size=\"3264,4928\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;2&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;NIKON D5100&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;1345317931&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;50&quot;,&quot;iso&quot;:&quot;100&quot;,&quot;shutter_speed&quot;:&quot;0.001&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;1&quot;}\" data-image-title=\"Astrofoto_setup_04\" data-image-description=\"\" data-medium-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_04-199x300.jpg\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_04-678x1024.jpg\" src=\"https:\/\/i0.wp.com\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_04.jpg?w=616&#038;h=930\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_04.jpg 3264w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_04-132x200.jpg 132w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_04-199x300.jpg 199w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_04-768x1160.jpg 768w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_04-678x1024.jpg 678w\" width=\"616\" height=\"930\" loading=\"lazy\" data-original-width=\"616\" data-original-height=\"930\" itemprop=\"http:\/\/schema.org\/image\" title=\"Astrofoto_setup_04\" alt=\"Piggyback astrofotografija\" style=\"width: 616px; height: 930px;\" \/> <\/a> <div class=\"tiled-gallery-caption\" itemprop=\"caption description\"> Piggyback astrofotografija <\/div> <\/div> <\/div> <!-- close group --> <div class=\"gallery-group images-1\" style=\"width: 620px; height: 934px;\" data-original-width=\"620\" data-original-height=\"934\" > <div class=\"tiled-gallery-item tiled-gallery-item-large\" itemprop=\"associatedMedia\" itemscope itemtype=\"http:\/\/schema.org\/ImageObject\"> <a href=\"http:\/\/www.astrobobo.net\/?attachment_id=1547\" border=\"0\" itemprop=\"url\"> <meta itemprop=\"width\" content=\"616\"> <meta itemprop=\"height\" content=\"930\"> <img loading=\"lazy\" decoding=\"async\" class=\"\" data-attachment-id=\"1547\" data-orig-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/02\/MW_Lagoon_16x30s_ISO1600_f2.8.jpg\" data-orig-size=\"596,900\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;1&quot;}\" data-image-title=\"MW_Lagoon_16x30s_ISO1600_f2.8\" data-image-description=\"\" data-medium-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/02\/MW_Lagoon_16x30s_ISO1600_f2.8-199x300.jpg\" data-large-file=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/02\/MW_Lagoon_16x30s_ISO1600_f2.8.jpg\" src=\"https:\/\/i0.wp.com\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/02\/MW_Lagoon_16x30s_ISO1600_f2.8.jpg?w=616&#038;h=930\" srcset=\"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/02\/MW_Lagoon_16x30s_ISO1600_f2.8.jpg 596w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/02\/MW_Lagoon_16x30s_ISO1600_f2.8-132x200.jpg 132w, http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2016\/02\/MW_Lagoon_16x30s_ISO1600_f2.8-199x300.jpg 199w\" width=\"616\" height=\"930\" loading=\"lazy\" data-original-width=\"616\" data-original-height=\"930\" itemprop=\"http:\/\/schema.org\/image\" title=\"MW_Lagoon_16x30s_ISO1600_f2.8\" alt=\"Mlije\u010dna staza snimljena modificiranim Nikon D5100, 50mm objektivom, 16x30 s ekspozicija, piggyback na teleskopu.\" style=\"width: 616px; height: 930px;\" \/> <\/a> <div class=\"tiled-gallery-caption\" itemprop=\"caption description\"> Mlije\u010dna staza snimljena modificiranim Nikon D5100, 50mm objektivom, 16&#215;30 s ekspozicija, piggyback na teleskopu. <\/div> <\/div> <\/div> <!-- close group --> <\/div> <!-- close row --> <\/div>\n","protected":false},"excerpt":{"rendered":"<p>Naj\u010de\u0161\u0107e pitanje koje se postavlja prilikom kupovine teleskopa je upravo kako napraviti fotografiju kroz teleskop. Fotografije \u0161arenih maglica i udaljenih galaksija mamac su za sve koji vole astronomiju. Odmah u startu morate znati da je astrofotografija kroz teleskop vrlo zahtjevna. Odabir teleskopa, monta\u017ee i aparata za fotkanje klju\u010dan je za uspje\u0161nu astrofotografiju. Zahtjevi su znatno [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":2072,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"gallery","meta":{"_acf_changed":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[3,120],"tags":[88,50],"class_list":["post-2055","post","type-post","status-publish","format-gallery","has-post-thumbnail","hentry","category-astrofotografija","category-prakticna-astronomija","tag-astrofotografija","tag-savjeti-3","post_format-post-format-gallery"],"acf":[],"aioseo_notices":[],"jetpack_featured_media_url":"http:\/\/www.astrobobo.net\/wordpress\/wp-content\/uploads\/2017\/04\/Astrofoto_setup_03_web.jpg","jetpack_sharing_enabled":true,"amp_enabled":true,"_links":{"self":[{"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=\/wp\/v2\/posts\/2055","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2055"}],"version-history":[{"count":24,"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=\/wp\/v2\/posts\/2055\/revisions"}],"predecessor-version":[{"id":2891,"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=\/wp\/v2\/posts\/2055\/revisions\/2891"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=\/wp\/v2\/media\/2072"}],"wp:attachment":[{"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2055"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2055"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.astrobobo.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2055"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}