Commons:Featured picture candidates/File:Urania leilus (moth).jpg

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File:Urania leilus (moth).jpg

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Voting period is over. Please don't add any new votes.Voting period ends on 15 Sep 2015 at 16:16:19 (UTC)
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Moth Urania Leilus.
  •  Info It seems. In real nothing is cut, black background is original, I recolored it to 100% (not with selecting which would make what you are describing), so no cutting (details are visile on edge). I also tried white, but no, there colors are much more pleasant too see on black. --Mile (talk) 18:12, 6 September 2015 (UTC)[reply]
  •  Oppose Interesting, but per Colin. This is very noticeable around the head. Also I wonder if focus stacking is all that necessary when most parts probably fall within focal plane, and given the result (not so sharp on the body). - Benh (talk) 18:54, 6 September 2015 (UTC)[reply]
  • When I do stack, I make as many to cover its DOF. Not more nor less. How many I need I see with focus peaking. Some closing of f wont help. Focal plane is radial, subject is planar, when on macro that means a huge difference. --Mile (talk) 20:21, 6 September 2015 (UTC)[reply]
  • I don't do extensive macro shooting, but I'd check for radial thing. When I shoot a sheet of paper with my macro lens, everything is sharp at wide aperture. If the lens' direction isn't on an axis perpendicular to that plane, that's another story... Anyone to share his insights? - Benh (talk) 21:00, 6 September 2015 (UTC)[reply]
  • I've no experience in photographing preserved specimens; so my comment is just an observation. The DOF is very limited (below 1mm) in actual macros. So this is what we get in a single shot (sorry for the poor quality; I just picked a random example from my works). Butterflies are more flat; but not so flat like a paper. I expect at least 3mm depth in this view. I don't fully agree with Archaeodontosaurus on using f/20 as it attracts diffraction. If there is an opportunity to stack; better stick with camera's best aperture values (f/5.6-f/8)? Increasing subject distance will increase DOF; but eliminate fine details. Then it is just a "closeup"; not true macros. (But from the file description, this moth has a wingspan of 10cm; so magnification is less.) Jee 06:13, 7 September 2015 (UTC)[reply]
  • The black background is a reference entomology especially butterflies. The specimen presented is not perfect, but it is not awful. The lighting is not very good. For butterflies the dorsal surface requires a stack of two images with closing values f20 and more. The ventral side (with legs) requires 3-4 images for the stack.
The most difficult is to have a perfect black background to avoid losing hair butterflies and cutting wings. It takes a particular matter as a felt no dust grains and remote throttle so it does not interfere (f20). The butterfly must be nearly 15cm of that background. --Archaeodontosaurus (talk) 05:10, 7 September 2015 (UTC)[reply]
PS: The Jee remark is just; there is an error in determining what is a Morphinae. --Archaeodontosaurus (talk) 08:47, 7 September 2015 (UTC)[reply]
Archaeodontosaurus, I am intrigued how you "fix" diffraction at f29? The reviews here and here (sharpness tab) suggest the captured resolution is much less towards f/22+. Clearly your D800 has an advantage over lesser cameras, but surely there are benefits to using f/16, say, and more stacks? I can appreciate that fewer stacks are better, as the technique isn't perfect and can introduce its own problems. Jee, yes this is just close-up photography (similar to product photography) and not macro (even if a macro lens is used). Still, I would like to know what technique can recover sharpness "lost" through diffraction. -- Colin (talk) 07:22, 7 September 2015 (UTC)[reply]
You're right and I know this; but I tried the different parameters and have a better sharpness by stacking least image and closing the aperture a little more than normal. Warning there out on the raw image diffraction but it is easy to remove before the stacks. --Archaeodontosaurus (talk) 07:51, 7 September 2015 (UTC)[reply]
  •  Info I did recover some damaged parts. Benh, Jee and Archaeodontosaurus explained you. You wont do any macro without stack, not here. Also agree with Jee, Archaeodontosaurus is using too closed f. I use sweet spot of lens, because stacking enables you that. And that is why many of Feautered right now in that category are actually not on pair with this. For instance [1], [2], [3]...actually most are not on pair with this quality. And I use 16 MPx camera, not full frame. I am actually surprised by voting so far. --Mile (talk) 08:03, 7 September 2015 (UTC)[reply]
  • Yes I'm aware stacking is often required to cover all DOF. I was just skeptical on a subject where focus points mostly lie on a flat surface, and given its larger size and the fact absolute aperture is smaller on a 4/3rd camera, yielding larger DOF by default. Stopping down at (say) f/16 isn't the same on a 4/3 than on a full frame. If you think these settings are best to you, fine. My vote is based on the result, not on what you went through to make the picture. - Benh (talk) 09:18, 7 September 2015 (UTC)[reply]
  • Having read a little here and [4] it seems Archaeodontosaurus's D800E plus an excellent macro prime lens plus some software sharpening at f/22 say, will outresolve a 21MP FF camera at f/5.6 (i.e best aperture), and will certainly beat a 16MP M43 camera. I assume Sony's 42MP and Canon's 50MP full frame sensors will be better again at macro. This is a case where having the best gear does make a difference. -- Colin (talk) 11:29, 7 September 2015 (UTC)[reply]
  •  I withdraw my nomination It become an essay about wrong specimen. Thanx to Archaeodontosaurus. Benh, I wrote you nice physical explanation of it. Colin put comments and it was all lost. On short again, there is no real focal plane, it just aporoximation of shape which is same distance from one point (sensor). That would be circle, or sphere in 3D. What are you used to Fraunhofer diffraction with your walkaround zoom, becomes Fresnel in makro world where strict r is used. DOF at this is in millimeters. You would miss your center positioning in this macro world on any given sunday. Even if you had luck in it, edges and centre on "planar" stuff are more than DOF is. And if stuff is 3d, with depth, than its obvious. Only question is will you make more shots on best f, or less on closed f and wide opened diffraction. Still don't getting it; try 100×100 plane 30 m in front of you, aim in center, focus on edge. What do you think, will be center in focus...its still same planar stuff. --Mile (talk) 13:51, 7 September 2015 (UTC)[reply]
  • hmm hope you don't feel too dissapointed. I like to ask questions when I have doubts. It's not like they are totally irrelevant. You make claims about some "spherical focal plane", which I've never heard of, and which I don't meet in real life shooting (and I mean macro size). If you have a proof, I'll be happy to check it. You might be right that we use approximation in most calculations, and I sort of remember we used more general formulas when looking at things at small scale. However I don't call a sensor "a point", it's a plane as far as I know. That may have its importance (?). Also throwing at me some esoterical words like "fresnel, fraunhofer" doesn't make your claim more true in my mind (I've last heard about them more than 10 years ago, I'm quite old). Anyways, my oppose was on the result alone. I initiated the topic only to learn from more experienced shooters on that topic and we have some, as you might have noticed. Have you considered people might have not voted on the picture because of... it? - Benh (talk) 14:28, 7 September 2015 (UTC)[reply]
  • Benh, that's the problem. You didn't ask any question. You put some statement like on one of my previous images. Then you change your mind which implicate not so sure behavior and misunderstanding. You made "wondering" which I tried to explain. That esoterical words like "fresnel, fraunhofer" explain all I said. But next time you can ask me first, I will try to explain. --Mile (talk) 15:02, 7 September 2015 (UTC) [reply]
Mile, "I wonder" means I not a firm statement, but it's based on my own (little experience). And yes after a second check, it was sharp enough so I striked my comment, and that doesn't affect the rest of the discussion. Also, you didn't contradict my own observations so far. I did shoot a bit of macro, and focal plane has always looked more like a plan than a sphere to me. I'd be happy that you prove me wrong, I'll sleep with more knowledge, that's all. Hope it's not that kind of pattern I often face where you talk about one thing to people, and they usually evade the topic by using those esoteric words they don't fully get either. I'm not sure putting down "Fresnel" alone on my optic school exam would have get me "A" mark, so it doesn't really explain it all. - Benh (talk) 15:39, 7 September 2015 (UTC) [reply]
Benh, hope this will enlighten you so that you can sleep well, today. :) BTW, I removed this withdrawn nom from the list; only page watchers can see the continuing discussion. Jee 15:53, 7 September 2015 (UTC)[reply]
Jee, Benh, I don't see the linked page as entirely helpful to the discussion. No camera has used a "simple lens" for 100 years. All serious compound lenses correct for field curvature and aim to produce a flat focal plane. Whether they achieve that is easily detectable on test charts and measuring equipment. A macro lens needs this especially since the DoF is so small for much of its use. Am I missing something? -- Colin (talk) 18:57, 7 September 2015 (UTC)[reply]
Colin I understand that basic lens design gets you spherical focal plane, but that it's not too critical when shooting from far distance, and maybe not noticeable in most situations (I personally have never checked but found it looks planar in my own shots). It becomes so when one gets closer, so they make more efforts when designing macro lens. Now that I think about it, resolutions charts used when testing lenses are... flat, which probably means that focal plans are "flat" as well. So my thinking is that u r right (and that this discussion was not in vain) - Benh (talk) 19:15, 7 September 2015 (UTC)[reply]
Benh, but my point is that what you call "basic lens design" is a single element, of which no camera uses. A spherical focal plane would also be noticeable in other applications too. It is why the focus-recompose method fails for large aperture -- because the focal plane is flat, not spherical. If you read the LensRentals blog, you'll see the flat focal plane of a lens being tested to its extreme and it is highly noticeable when it is not flat but curved or wavy -- for test charts and portraits anyway, for a wide-angle lens stopped down, nobody cares. -- Colin (talk) 21:21, 7 September 2015 (UTC)[reply]
This explains "Field Curvature Aberrations" a bit more. According to them "while the artifacts and aberrations have not been totally eliminated, the high-end models are now capable of producing superb photomicrographs."
But what important for us is to find the best aperture-subject distance combination for our equipment. While playing here, I found that my Sigma 150mm can produce 1:1 images at 600mm sensor to subject distance. But then the smallest subject which can fill the image is 15.8mm (as the damselfly head I linked above). (It was taken by setting the focus first following the 1:1 mark on lens and then move to and fro to focus.) At f/8 (effective=f/8+1=f/16 except for Nikon cameras), here the DOF is 0.67mm. It will become 1.35mm at f/16 (effective=f/32). But if I increased the subject distance to 670mm, I get 2.02mm DOF at f/8 though magnification is reduced to 0.51x. So my conclusion is it is better to increase subject distance than stopping down to achieve enough DOF. (Correct me if I missed any point.) Jee 02:31, 8 September 2015 (UTC)[reply]
That link is for microscopes, so a different kind of optic (though the physics are the same) than camera lenses. Anyway, I thought there was some claim that modern camera lenses might not have a flat plane of focus, and they certainly do -- within the limits of their technical quality. Increasing subject distance leads to a smaller image in the frame, and so a loss of resolution also. I won't disagree with your maths but the image above, if 10cm wide, is not a macro photograph. That's just standard product photography. -- Colin (talk) 06:59, 8 September 2015 (UTC)[reply]
  • This is going a bit off-topic. But hope Mile will understand we're trying to help. I'm not a subject expert; but in my initial search itself I felt doubt about the ID. That's why I asked Archaeo's opinion. So this nom anyway need to be withdrawn until the ID (species level) is found. Focus plain: Yes; spherical focus plain is correct for most lens. But my understanding (from read somewhere) is that macro lens are designed in such a way to produce constant focus distance. It is because every millimeter is important. I'm sure Archaeo can help you on producing better shots of preserved specimens as he has years of experience in it. Jsut take it as an initial "circle of confusion". :) Jee 14:41, 7 September 2015 (UTC)[reply]
All lens design aims for a flat plane of focus, not curved as one would get for "same distance from one point". Whether your lens achieves this depends on how much money you spend and how flat you need it to be. Perhaps I am missing something, but that's my understanding. -- Colin (talk) 15:25, 7 September 2015 (UTC)[reply]

* Support--Soundwaweserb (talk) 15:22, 7 September 2015 (UTC) Its withdrawn. Makenjen je sa glasanja. Hvala ipak. --Mile (talk) 15:26, 7 September 2015 (UTC)[reply]

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