{"id":274,"date":"2006-10-31T22:58:58","date_gmt":"2006-10-31T13:58:58","guid":{"rendered":"https:\/\/regex.info\/blog\/2006-10-31\/274"},"modified":"2007-12-18T23:41:11","modified_gmt":"2007-12-18T14:41:11","slug":"sigma-30mm-f14-prime-lens","status":"publish","type":"post","link":"https:\/\/regex.info\/blog\/2006-10-31\/274","title":{"rendered":"Sigma 30mm f\/1.4 Prime Lens"},"content":{"rendered":"\n\n<p>As I <a href=\"\/blog\/2006-10-05\/263\">recently wrote<\/a>, <span class='nobr'>I love my<\/span> <span class='nobr'>Nikon 18<\/span>-200 zoom except that it's <span class='nobr'>a bit<\/span> &#8220;slow&#8221;,\noptically speaking: at f\/3.5-5.6, the lens diameter is too small to allow\nenough light for reasonable shutter speeds in low-light situations. So, two\nweeks ago, <span class='nobr'>I finally<\/span> picked up a <a\nhref=\"http:\/\/www.sigma-imaging-uk.com\/lenses\/dclenses\/30mm.htm\">Sigma 30mm\nf\/1.4<\/a> prime lens.\n\n<\/p>\n<style type=\"text\/css\">\n.ic {\n  display: block;\n  text-align: center;\n  margin-left: auto;\n  margin-right: auto;\n  margin-top: 20px;\n  margin-bottom: 20px;\n}\n\n.ic IMG {\n  margin-bottom: 5px;\n}\n\n.gr {\n  color: gray;\n  font-size: 85%;\n}\n<\/style>\n<p>\n\nAt f\/1.4, it's 3 stops &#8220;faster&#8221; (optically speaking) than my current lens,\nmeaning it can allow 8 times more light, in turn allowing <span class='nobr'>a shutter<\/span> speed 8\ntimes faster. That makes it great for low-light situations.\n\n<\/p><p>\n\nA byproduct of a large aperture (low &#8220;f&#8221; number like 1.4) is that it can\nproduce an extremely shallow depth of field, meaning that most things are out\nof focus except for objects more or less exactly such-and-such <span class='nobr'>a distance<\/span>\nfrom the lens. This can be used creatively in <span class='nobr'>a variety<\/span> of ways.\n\n<\/p><p>\n\nBecause of the shallow depth of field, focusing must be <i>spot on<\/i> or\nwhat you intend to be sharp won't be. Unfortunately, this lens has <span class='nobr'>a\nreputation<\/span> for having auto-focusing problems: if you're lucky, the one you\nget is perfect, but if you get <span class='nobr'>a bad<\/span> one, the focus point can be <span class='nobr'>a few<\/span>\ninches to the front or rear of where you told it to focus. <span class='nobr'>If you get<\/span> one\nof these, you have to either return it to the store and try your luck with\nanother, or send it to Sigma to have them fix it.\n\n<\/p><p>\n\nLooking at one of the first photos <span class='nobr'>I took,<\/span> <span class='nobr'>I knew I<\/span>'d gotten <span class='nobr'>a lemon<\/span>:\n\n<\/p>\n\n<div class='ic'><a href=\"\/i\/_JEF021845.jpg\" name='021845'><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021845_sm.jpg\" width=\"417\" height=\"600\"\nborder=\"0\"\nid=\"iJEF021845\"\/><\/a><br\/>\n<span class='gr'>Sigma 30mm Prime, ISO 500, f\/1.4, 1\/<sub>30<sup>th<\/sup><\/sub> sec<br\/>Click Image to Enlarge<\/span><\/div>\n\n<p>Clicking on the picture above to see <span class='nobr'>a larger<\/span> version shows pretty much\nnothing is in focus, although you can see <span class='nobr'>a stripe<\/span> across the width of the\npaper Anthony's looking at is more in focus than the rest. <span class='nobr'>The focus<\/span> point\nwas his left eyelash (the one on our right), but the lens missed it wildly.\n<\/p>\n\n<p>Anyway, I didn't know about that until later when <span class='nobr'>I looked<\/span> at them on\nthe computer. When <span class='nobr'>I first<\/span> got back from the store, <span class='nobr'>I'd had time<\/span> to take\njust <span class='nobr'>a few<\/span> test shots of Anthony before we headed out to eat with Fumie's\nfolks. <span class='nobr'>It was dark<\/span> out and <span class='nobr'>I wanted<\/span> to see what the large aperture could\ndo, so <span class='nobr'>I left<\/span> it wide open most of the time. <span class='nobr'>As I said<\/span>, <span class='nobr'>I didn't<\/span> know about\nthe focus problem until <span class='nobr'>I got<\/span> back, so many of the pictures below have\nfocus issues.<\/p>\n\n<p>As with most pictures I put in my posts, clicking on them yields <span class='nobr'>a\nlarger<\/span> version.<\/p>\n\n<div class='ic'><a href=\"\/i\/_JEF021853.jpg\" name='021853'><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021853_sm.jpg\" width=\"650\" height=\"499\"\nborder=\"0\"\nid=\"iJEF021853\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.4, 1\/<sub>20<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<p>We went to a restaurant that's about <span class='nobr'>a five<\/span>-minute walk away. <span class='nobr'>It specialized<\/span> in <a href=\"http:\/\/en.wikipedia.org\/wiki\/Fugu\">Fugu<\/a>\n(pufferfish) and <a href=\"http:\/\/en.wikipedia.org\/wiki\/Matsutake\">Matsutake\nmushrooms<\/a>.<\/p>\n\n<p>As you can see in the upper-left of the <a\nhref=\"\/i\/_JEF021859.jpg\">large version<\/a> of the next\npicture, my copy of the lens suffers from severe <a\nhref=\"http:\/\/en.wikipedia.org\/wiki\/Chromatic_aberration\">chromatic\naberration<\/a>. <span class='nobr'>The black<\/span> letters on the white sign show <span class='nobr'>a strong<\/span> blue\nfringe, so strong that <span class='nobr'>I wondered<\/span> if it was actually part of the sign. (<span class='nobr'>I\nchecked<\/span> the next day; it's not.)<\/p>\n\n<div class='ic'><a href=\"\/i\/_JEF021859.jpg\" name='021859'><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021859_sm.jpg\" width=\"388\" height=\"550\"\nborder=\"0\"\nid=\"iJEF021859\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.4, 1\/<sub>320<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<div class='ic'><a href=\"\/i\/_JEF021860.jpg\" name='021860'><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021860_sm.jpg\" width=\"700\" height=\"486\"\nborder=\"0\"\nid=\"iJEF021860\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.4, 1\/<sub>180<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<p>To take the picture above, <span class='nobr'>I had my<\/span> back pressed deep into the corner of\nthe room. At 30mm, this lens is just <span class='nobr'>a bit<\/span> too long for <span class='nobr'>a confined<\/span> space\nlike this. <span class='nobr'>I really<\/span> would have preferred <span class='nobr'>a 24mm<\/span> over <span class='nobr'>a 30mm,<\/span> but it seems\nno one makes such <span class='nobr'>a Nikon<\/span>-mount 24mm f\/1.4 lens.<\/p>\n\n<div class='ic'><a href=\"\/i\/_JEF021865.jpg\" name='021865'><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021865_sm.jpg\" width=\"700\" height=\"488\"\nborder=\"0\"\nid=\"iJEF021865\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.4, 1\/<sub>160<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<p>Despite the picture above having nothing in focus except the edge of the\ntray in front of Anthony, it's <span class='nobr'>a good<\/span> example of how <span class='nobr'>a shallow<\/span> depth of\nfield can be used to isolate <span class='nobr'>a subject.<\/span> <span class='nobr'>If the focus<\/span> had been correct,\nAnthony would be crisp and sharp, but the background and stuff on the back\nedge of the table would all remain out of focus. With the smaller aperture\nof <span class='nobr'>a common<\/span> lens, the background would be more in focus, more\ndistracting.<\/p>\n\n<p>In the next picture, <span class='nobr'>I have Fumie<\/span> and the foreground out of focus, with\nthe waitress the main point of focus.<\/p>\n\n<div class='ic'><a href=\"\/i\/_JEF021868.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021868_sm.jpg\" width=\"700\" height=\"486\"\nborder=\"0\"\nid=\"iJEF021868\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.4, 1\/<sub>100<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<div class='ic'><a href=\"\/i\/_JEF021869.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021869_sm.jpg\" width=\"700\" height=\"486\"\nborder=\"0\"\nid=\"iJEF021869\"\nphotostream=\"misc\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.4, 1\/<sub>320<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<p>The shot above really highlights the shallow depth of field.<\/p>\n\n<p>The shot below doesn't say much about the lens; it's just <span class='nobr'>a nice<\/span> shot of\nFumie's dad, despite being out of focus.<\/p>\n\n<div class='ic'><a href=\"\/i\/_JEF021876.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021876_sm.jpg\" width=\"615\" height=\"490\"\nborder=\"0\"\nid=\"iJEF021876\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.6, 1\/<sub>125<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<div class='ic'><a href=\"\/i\/_JEF021887.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021887_sm.jpg\" width=\"700\" height=\"486\"\nborder=\"0\"\nid=\"iJEF021887\"\nphotostream=\"anthony\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.4, 1\/<sub>180<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<div class='ic'><a href=\"\/i\/_JEF021892.jpg\" name='021892'><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021892_sm.jpg\" width=\"580\" height=\"510\"\nborder=\"0\"\nid=\"iJEF021892\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.4, 1\/<sub>100<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<p>I'd played around a lot with the shallow depth-of-field the lens could\nproduce, but <span class='nobr'>I wanted<\/span> to test its light-gathering abilities more. <span class='nobr'>I thought<\/span> I'd take <span class='nobr'>a picture<\/span> of the river next to our building, but Anthony was fussy\nand would have none of it. <span class='nobr'>In the end<\/span>, <span class='nobr'>I was able<\/span> to take one shot\nhand-held with just one hand while holding <span class='nobr'>a fussy,<\/span> wriggling Anthony in\nthe other:<\/p>\n\n<div class='ic'><a href=\"\/i\/_JEF021897.jpg\" name='021897'><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF021897_sm.jpg\" width=\"700\" height=\"487\"\nborder=\"0\"\nid=\"iJEF021897\"\/><\/a><br\/><span\nclass='gr'>Sigma 30mm Prime, ISO 800, f\/1.4, 1\/<sub>5<sup>th<\/sup><\/sub>\nsec<\/span><\/div>\n\n<p>It's clearly out of focus, and not the lens's fault this time, but\nconsidering the situation <span class='nobr'>I think<\/span> it's pretty darn good. <span class='nobr'>My other<\/span> lens\nwould have needed an almost two-second exposure, which would have yielded\nnothing but <span class='nobr'>a blur.<\/span> (However, under better conditions my 18-200 can produce\nnice night photos, such as <a\nhref=\"\/blog\/2006-04-18\/180\">this 30-second exposure<\/a>\nfrom <span class='nobr'>a bit<\/span> further down the river, looking towards where the above picture\nwas taken.)<\/p>\n\n<p>Back at home, once I looked at the first batch of photos, <span class='nobr'>I realized<\/span> that <span class='nobr'>I had<\/span> <span class='nobr'>a lemon,<\/span> and kept it to mostly manual focus for the next few\ndays. (This had me pining for a <a\nhref=\"\/blog\/2007-08-22\/550\">split-focus\nscreen for my D200<\/a>, like film SLRs of days past. Does anyone in Kansai\ninstall them?) The photos from my previous three posts about Anthony's\nbirthday presents (<a href=\"\/blog\/2006-10-23\/271\">one<\/a>,\n<a href=\"\/blog\/2006-10-24\/272\">two<\/a>, <a\nhref=\"\/blog\/2006-10-29\/273\">three<\/a>) were all taken with\nthis lens.<\/p>\n\n<p>In particular, this one photo was worth the cost of the lens:<\/p>\n\n<div class='ic'><a href=\"\/i\/_JEF022032.jpg\" name='022032'><img loading=\"lazy\" decoding=\"async\" src=\"\/i\/_JEF022032_sm.jpg\" width=\"700\" height=\"559\"\nborder=\"0\"\nid=\"iJEF022032x2\"\nphotostream=\"anthony\"\/><\/a><br\/><span class='gr'>Sigma 30mm Prime, ISO 800, f\/1.4,\n1\/<sub>50<sup>th<\/sup><\/sub> sec<\/span><\/div>\n\n\n<p>This picture just couldn't have been taken with an f\/2.8 lens (f\/2.8\nbeing <span class='nobr'>a common<\/span> maximum aperture on many pro-level lenses), as such <span class='nobr'>a lens<\/span>\nwould have needed a 1\/<sub>15<sup>th<\/sup><\/sub>-second exposure, and no\nfour-year-old stays still for that long. Well, <span class='nobr'>I could<\/span> have pushed the ISO\nway up to recover some of the shutter speed, but the result just wouldn't\nhave been the same.<\/p>\n\n   \n\n<p><b>Update:<\/b> the ghosting problem originally reported in this\nparagraph is likely not the lens' fault, but probably due to the fact that\n<span class='nobr'>I had<\/span> <span class='nobr'>a filter<\/span> on the lens (<span class='nobr'>a clear<\/span>-glass &#8220;protector&#8221; filter).\nI've not yet re-tested with my recently-acquired good copy of this lens,\nbut <span class='nobr'>I wanted<\/span> to at least put <span class='nobr'>a note<\/span> here. Originally, <span class='nobr'>I wrote.<\/span>..\n\n<span style='color:gray'>\nAs much as <span class='nobr'>I cherish<\/span> this picture, it shows yet <i>another<\/i> problem\nwith this lens: ghosting. <span class='nobr'>The version<\/span> above is almost just as it came out\nof the camera. Looking at (<span class='nobr'>a reduced<\/span>-size copy of) the <a\nhref=\"\/i\/_JEF022032o.jpg\">original<\/a>, you'll see that <span class='nobr'>I\nused<\/span> Photoshop to remove ghost reflections of the candle flames that\nappeared on and next to his head (as well as <span class='nobr'>a light<\/span> outside showing\nthrough the curtain).<\/span><\/p>\n\n<p>I knew that this lens really sucked in the light, but with focus\nproblems, chromatic aberration, <span style='color:gray'>and\nghosting,<\/span> the copy <span class='nobr'>I had<\/span> just sucked. <span class='nobr'>I brought<\/span> it back to the\nstore, and while there <span class='nobr'>I was<\/span> able to test another copy (using <span class='nobr'>a focus<\/span> test chart among\nother methods <b>[Update<\/b>: here's the <a\nhref=\"\/blog\/2007-01-23\/369\">better focus-test\nchart<\/a><b>]<\/b> that I've used since) and its focus was clearly better than the copy <span class='nobr'>I had.<\/span> <span class='nobr'>In the end<\/span> <span class='nobr'>I returned<\/span> it and got my money back instead of exchanging,\nmostly because I'd since learned of <span class='nobr'>a place<\/span> <span class='nobr'>I could<\/span> get it for 20%\nless.<\/p>\n\n<p>Today, <span class='nobr'>I reordered<\/span> it at <span class='nobr'>a different<\/span> store (for $100 less) along with\ntwo Nikon lenses, a <a\nhref=\"http:\/\/www.nikonusa.com\/template.php?cat=1&amp;grp=5&amp;productNr=2147\">17-55mm\nf\/2.8G IF AF-S DX<\/a> and a <a\nhref=\"http:\/\/www.nikonusa.com\/template.php?cat=1&amp;grp=5&amp;productNr=2139\">70-200mm\nf\/2.8G IF AF-S VR<\/a>. <span class='nobr'>I expect<\/span> to have them in time for fall foliage\npictures. I'll use the Sigma f\/1.4 lens only in special low-light\nsituations, or for its shallow depth of field. Otherwise, <span class='nobr'>I expect<\/span> the two\nnew Nikon zooms to get <span class='nobr'>a lot<\/span> of use, leaving my current f\/3.5-5.6 18-200\nzoom as an all-in-one walkaround\/travel lens.<\/p>\n\n\n<p> We'll see. <\/p>\n\n<p><b>Update:<\/b> finally <a href=\"\/blog\/2007-03-29\/407\">got <span class='nobr'>a good<\/span> one<\/a>.<\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"<p>As I recently wrote, I love my Nikon 18-200 zoom except that it's a bit \"slow\", optically speaking: at f\/3.5-5.6, the lens diameter is too small to allow enough light for reasonable shutter speeds in low-light situations. So, two weeks ago, I finally picked up a Sigma 30mm f\/1.4 prime lens. <\/p> <p> At f\/1.4, it's 3 stops \"faster\" (optically speaking) than my current lens, meaning it can allow 8 times more light, in turn allowing a shutter speed 8 times faster. That makes it great for low-light situations. <\/p><p> A byproduct of a large aperture (low \"f\" number like [...]","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16,7],"tags":[],"_links":{"self":[{"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/posts\/274"}],"collection":[{"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/comments?post=274"}],"version-history":[{"count":0,"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/posts\/274\/revisions"}],"wp:attachment":[{"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/media?parent=274"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/categories?post=274"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/tags?post=274"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}