01af Posted October 20, 2011 Share #21 Posted October 20, 2011 Advertisement (gone after registration) No.Can you elucidate? All other things being equal, a smaller sensor leads to less depth-of-field—hence 'No.' All other things being equal again, a smaller sensor plus a shorter (equivalent) focal length leads to more depth-of-field—hence 'Yes.' The primary reason why a cell phone camera has vast depth-of-field is not the small size of the sensor but the short focal length of the lens. Link to post Share on other sites More sharing options...
Advertisement Posted October 20, 2011 Posted October 20, 2011 Hi 01af, Take a look here Hyperfocal scales on Lenses and crop factor cameras (M8). I'm sure you'll find what you were looking for!
squarenegs Posted October 20, 2011 Share #22 Posted October 20, 2011 For a given focal length lens projecting a constant image size, the depth of field will be the same no matter what the size of the capture medium. Large format film or a tiny P&S sensor, for example, will have no bearing on the depth of field of a given focal length lens, when the image elements are recorded at the same size on the different mediums. The size of the projected image and the size of the capture area are often confused. They are not the same thing. At a fixed distance to the subject (fixed image size) depth of field is a function of focal length. Link to post Share on other sites More sharing options...
01af Posted October 20, 2011 Share #23 Posted October 20, 2011 For a given focal length lens projecting a constant image size, the depth of field will be the same no matter what the size of the capture medium. [...] At a fixed distance to the subject (fixed image size) depth-of-field is a function of focal length. Depth-of-field is not, repeat: NOT a property of the lens or the focal length thereof but a property of the image. Hence it depends (for a given aperture and focus distance) on both the focal length and the image size. Link to post Share on other sites More sharing options...
HeinzX Posted October 20, 2011 Share #24 Posted October 20, 2011 Same lens, same distance to the o b j e c t you want to photograph, same aperture same depth of field. DOF depends on aperture and image ratio and has nothing to do with crop or no crop. The image ratio does not depend on crop or no crop. What you see in your finder if you use a crop is an outcast of the picture you would have with a full frame. But was happens in this case is the following - if you would like the object to fill up your whole rangefinder or chip with a crop camera you are not able to go as near as with a full format, because due to the other angle of the crop compared with full frame you will come out of boundaries of your rangefinder. T h i s changes in fact the image ratio, because the image ratio depends on the d i s t a n c e to the object which should be taken a picture of and the focal length of the lens. Therefore in this case you reach a higher DOF, because the image ratio is lower. Which a fullframe camera compared with a crop it works just the other way around. You can or must go nearer with the camera to fill the chip, t h e r e f o r e you have a bigger image ratio than with the crop and provided you use same lens and same aperture, you have a higher image ratio and therefore a lower DOF. Following this, the answer of Leica is absolutely right. I have done my best to give this explanation in English, with is not my mother tongue, therefore please excuse mistakes. Link to post Share on other sites More sharing options...
lct Posted October 20, 2011 Share #25 Posted October 20, 2011 Sorry to repeat at nauseam but DoF depends on the size of the circle of confusion (CoC) and the latter depends on the size of the capture medium. The smaller the sensor, the smaller the CoC. Link to post Share on other sites More sharing options...
01af Posted October 20, 2011 Share #26 Posted October 20, 2011 Same lens, same distance to the object you want to photograph, same aperture, same depth of field. DOF depends on aperture and image [magnification] and has nothing to do with crop or no crop. The image [magnification] does not depend on crop or no crop. Sigh ... will the supply of persons repeating this nonsense over and over ever come to an end? Saying that depth-of-field depends on aperture and magnification only is a simplifying approximation that holds only when the magnification is large, i. e. in macro photography—and, to a degree, when shooting with long focal lengths—, but not in general. In general, depth-of-field depends on: image format, focal length, subject distance, and aperture ... plus a few fairly elusive factors which we may ignore for now (like e. g. pupil magnification, residual spheric aberration, and maybe a few more I'm not aware of). Link to post Share on other sites More sharing options...
SJP Posted October 20, 2011 Share #27 Posted October 20, 2011 Advertisement (gone after registration) All other things being equal, a smaller sensor leads to less depth-of-field—hence 'No.' All other things being equal again, a smaller sensor plus a shorter (equivalent) focal length leads to more depth-of-field—hence 'Yes.' The primary reason why a cell phone camera has vast depth-of-field is not the small size of the sensor but the short focal length of the lens.OK I agree with that, as stated previously I prefer to compare full frame focal lengths to "equivalent" focal length on cropped or larger senors, i.e at the same angular view. Also, just as a technical point how do we deal with CoC in the "all else being equal" sense of the word? The changed(?) CoC relates to the normal viewing distance so that may be purely a function of crop/expansion factor. Then we have the interesting situation that the DoF of a 35mm lens on the M8 is shallower than of the same 35mm lens on the M9 but deeper than the "equivalent focal length" (ca. 50 mm) lens on the M9, all at the same f/value. Confused? You won't be after this No wonder so many people dislike DoF, CoC etc. OK, time to take some pics. Link to post Share on other sites More sharing options...
SJP Posted October 20, 2011 Share #28 Posted October 20, 2011 Sigh ... will the supply of persons repeating this nonsense over and over ever come to an end? <snip> Probably not, but we usually win given perseverance..... Usually. Apparently, it is a tricky concept for many to understand that the final magnification (from sensor to screen/print) is a factor you also have to take into account. All the other factors you mention are relevant to some extent but may add to the confusion I fear. Link to post Share on other sites More sharing options...
squarenegs Posted October 20, 2011 Share #29 Posted October 20, 2011 Holy cats!!! Everyone read this: DOF Now, I'm out'a this poodle fight before I get my Summarit bit. Link to post Share on other sites More sharing options...
HeinzX Posted October 20, 2011 Share #30 Posted October 20, 2011 Here you find a long article dealing with DOF in Engish, I hope that there are no objection against this. Depth of field - Wikipedia, the free encyclopedia Link to post Share on other sites More sharing options...
ho_co Posted October 20, 2011 Share #31 Posted October 20, 2011 For those who argue that DoF is the same for a given focal length and aperture and independent on format: That assumption is disproved by the Minox (8x11 mm), whose lens was a 15/3.5. Its hyperfocal distance was 1 m. That means that its depth of field was from 0.5 m to infinity when focused at 1 m. Try that with your Super-Elmar-R 15. Link to post Share on other sites More sharing options...
ho_co Posted October 20, 2011 Share #32 Posted October 20, 2011 Olaf Stefanus reported in an LFI article ("Form Follows Format," LFI 3/2006, pp 40-47) on a presentation on this topic by Peter Karbe, Leica's head lens designer. Upshot: To understand how DoF, FoV and crop factor are related, multiply not only the focal length but also the marked aperture by the crop factor. Thus, a 28/2 becomes on the M8 the equivalent of a 37/2.7 (full frame; crop factor 1.3333). And a 15/3.5 on the 8x11 Minox format acts like a 48mm f/11 (full frame; crop factor 3.18) in terms of field of view and depth of field. Link to post Share on other sites More sharing options...
Jeff S Posted October 20, 2011 Share #33 Posted October 20, 2011 ...as described in the link provided in post #17. Jeff Link to post Share on other sites More sharing options...
brianv Posted October 20, 2011 Share #34 Posted October 20, 2011 "Lenses in Photography", Kingslake, 1951. "a depth of field table or scale should be taken with many mental reservations, and depths stated to small fractions of an inch can be somewhat misleading. Moreover, the observer's eye is not always situated at the correct center of perspective, and hence the depth may be multiplied or divided by a factor depending on his departure from the proper viewing conditions, which may reach as much as 2 or 3 or more. This hair-splitting arguments about depth of field data becomes absolutely worthless". So- DOF is subjective. It's opinion. The absolute size of a circle of confusion is ruled by physics. The interpretation of what is and is not acceptable for an enlargement is subjective. The opinion of the person viewing the final results is all that matters with respect to DOF, and the absolute placement of the little lines on the lens are nothing more than "Feel Good" indicators on the part of the maker of the lens. Link to post Share on other sites More sharing options...
01af Posted October 20, 2011 Share #35 Posted October 20, 2011 Holy cats!!! Everyone read this: DOF Oh no. Everyone better ignore that; it's full of errors, mistakes, and nonsense. Here you find a long article dealing with DOF in Engish, I hope that there are no objection against this. Depth of field - Wikipedia, the free encyclopedia Hey! Wikipedia articles on photographic or photo-technical topics usually are deficient—but this one is surprisingly good. After skimming it quickly, I didn't see any glaring errors. Still the best Internet resource on depth-of-field, in my opinion, is found on Paul van Walree's website. See Depth of field That assumption is disproved by the Minox (8 × 11 mm), whose lens was a 15 mm 1:3.5. Its hyperfocal distance was 1 m. That means that its depth-of-field was from 0.5 m to infinity when focused at 1 m. Are you sure!? With a maximum COC of 0.009 mm (i. e. 1/1,500th of the format's diagonal), the Minox's hyperfocal distance would be 7 m. With a maximum COC of 0.03 mm (i. e. the same as commonly assumed for 35-mm format), the hyperfocal distance would be 2 m. So there is no way the hyperfocal distance could have been anywhere close to 1 m at f/3.5. So why do you think it was 1 m? So—DOF is subjective. It's opinion. While the absolute extension of depth-of-field may be subjective to a degree, the factors that increase or decrease DOF are not. The maximum COC diameter we usually agree upon may or may not match your personal viewing conditions. But once you chose your maximum COC diameter that subjectively appears sharp to you then everything is pure and objective math from there. Link to post Share on other sites More sharing options...
jaapv Posted October 20, 2011 Share #36 Posted October 20, 2011 Holy cats!!! Everyone read this: DOF Now, I'm out'a this poodle fight before I get my Summarit bit. I would not regard that article as authorative on the subject- it is certainly not error-free and is in parts misleading. Link to post Share on other sites More sharing options...
ho_co Posted October 21, 2011 Share #37 Posted October 21, 2011 ... Are you sure!? With a maximum COC of 0.009 mm (i. e. 1/1,500th of the format's diagonal), the Minox's hyperfocal distance would be 7 m. With a maximum COC of 0.03 mm (i. e. the same as commonly assumed for 35-mm format), the hyperfocal distance would be 2 m. So there is no way the hyperfocal distance could have been anywhere close to 1 m at f/3.5. So why do you think it was 1 m? ... Thanks, Olaf! You're right. The numbers I gave were simply from memory and wrong. Judging from the photo at File:MinoxTLX.jpg - Wikipedia, the free encyclopedia, it was labeled for a hyperfocal distance of 2 m, as you suggest, with DoF from ca 1 m to infinity. Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Minox prints were normally 2.5 x 3.5 in IIRC, so the camera's point-n-shoot mode basically consisted in setting one distance and never changing it for normal situations. The measuring chain had beads installed for all of the engraved closest distances, down to 8 in (foot/inch scale as shown in the shot of the Minox B on that page). BTW, Olaf, it is quite rude to misquote someone without acknowledging the incorrect quote. I said the camera had "a 15/3.5," not "a 15 mm 1:3.5" lens. I dislike the pretension of the second formulation and don't like to see it assigned my name. That's personal preference, but faking quotations is very unprofessional. Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! Minox prints were normally 2.5 x 3.5 in IIRC, so the camera's point-n-shoot mode basically consisted in setting one distance and never changing it for normal situations. The measuring chain had beads installed for all of the engraved closest distances, down to 8 in (foot/inch scale as shown in the shot of the Minox B on that page). BTW, Olaf, it is quite rude to misquote someone without acknowledging the incorrect quote. I said the camera had "a 15/3.5," not "a 15 mm 1:3.5" lens. I dislike the pretension of the second formulation and don't like to see it assigned my name. That's personal preference, but faking quotations is very unprofessional. ' data-webShareUrl='https://www.l-camera-forum.com/topic/164202-hyperfocal-scales-on-lenses-and-crop-factor-cameras-m8/?do=findComment&comment=1822409'>More sharing options...
pgk Posted October 21, 2011 Share #38 Posted October 21, 2011 Do the hyperfocal scales on all manual lenses remain true when using a crop factor cameras like the M8? or do they only work for the full frame cameras (m9)? The simplest way to determine whether they do is to try it. You can get yourself totally bamboozled trying to figure out the theory when all you have to do is to take a few shots at different apertures and then compare them. Of course, even this requires some standardisation of the output viewing format so you will have to decide how you will best/normally view the screen/prints so that you have some sort of personal 'standard' to judge against. Personally I tend to use the scales for an aperture 2 tops wider than the one I'm using, but this is based roughly on a 15" x 10" print and satisfies my closest scrutiny (which is actually how I suspect most people viewing a print tend to look at it to see the detail it contains). Just my personal method which yield prints that satisfy me. Link to post Share on other sites More sharing options...
01af Posted October 21, 2011 Share #39 Posted October 21, 2011 ... it was labeled for a hyperfocal distance of 2 m, as you suggest, with depth-of-field from ca 1 m to infinity. You are—falsely—accusing me of misquoting you but then you badly misquote me. I never suggested a hyperfocal distance of 2 m for the Minox camera. When looking closely at the Wikipedia image then it seems to me the hyperfocal distance was supposed to be 4 m, with depth-of-field from 2 m to infinity. This implies a maximum circle-of-confusion diameter of 0.015 mm which is approx. 1/1,000th of the format diagonal ... a rather generous value by today's standards. By the way, Olaf, it is quite rude to misquote someone without acknowledging the incorrect quote. I said the camera had "a 15/3.5," not "a 15 mm 1:3.5" lens. I dislike the pretension of the second formulation ... Frankly, I don't care whether you like it or not. It's the correct way to put it, and '15/3.5' just is the abbreviation thereof. I dislike the excess use of abbreviations which is rude against the reader. When I quote someone's text then it will become part of my text which I don't want to contain unnecessary abbreviations ... or typos. So I will correct these. It is far beyond the point to call this a 'misquote.' Unlike you, I didn't distort anything you said, did I? Link to post Share on other sites More sharing options...
SJP Posted October 22, 2011 Share #40 Posted October 22, 2011 I would not regard that article as authorative on the subject- it is certainly not error-free and is in parts misleading. Like the curates egg "good in parts" anyway I liked this turn of phrase: unless I'm struggling with depth of field and simply can't stop down far enough with a particularly lens to achieve enough depth of field for a particular shot I think, but am not sure, that most of us are struggling to get less depth of field:) If you stop down far enough all lenses are the same. Link to post Share on other sites More sharing options...
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