jcs Posted April 10, 2017 Share Posted April 10, 2017 @tupp every single example where you state there's a difference between the two images is related to optics, not sensor size, or the tester didn't/couldn't set the systems up for equivalence. The differences between the Fujinon lenses is one has the APD filter (https://en.wikipedia.org/wiki/Apodization) and the other doesn't, which explains the difference in bokeh. Nothing to do with sensor size. Are you familiar with the scientific method? https://en.wikipedia.org/wiki/Scientific_method. Your conjecture is as sensor size gets larger <insert specific properties which can be tested and characterized here>. Your Null Hypothesis is thus, "Sensor size has no effect by itself on the captured image". Now do your experiments using the scientific method. Do you own a camera and lenses? If not can you rent them? I only ask because you've never posted any of your own work. In your experiments you'll try your hardest to show that sensor size has no effect, eliminating as many variables as possible. Only after rigorous testing to try to eliminate sensor size as having an effect, can you then reject your null hypothesis and form a predictable theory which accurately describes the effects sensor size has on the captured image, and most importantly your new theory will be able to make predictions which can then be tested to further validate that your understanding of the system is correct. And that, brother, is currently the best process human beings have for understanding what's real, or not. IronFilm, hyalinejim and noone 3 Quote Link to comment Share on other sites More sharing options...
tupp Posted April 10, 2017 Share Posted April 10, 2017 47 minutes ago, jcs said: @tupp every single example where you state there's a difference between the two images is related to optics, not sensor size, or the tester didn't/couldn't set the systems up for equivalence. Are you forgetting once again that I (and others) have stated I am not referring to the sensor/film size? My (and others') contention is that there are properties generally inherent in the optics designed for a certain sensor/film size. 47 minutes ago, jcs said: The differences between the Fujinon lenses is one has the APD filter (https://en.wikipedia.org/wiki/Apodization) and the other doesn't, which explains the difference in bokeh. I thought that I made that clear. However, with this comment, you seem to have inadvertently admitted that there is a variable that affects DOF and focus roll-off that is not considered in the equivalence principle and in the DOF calculation. Is that true? 47 minutes ago, jcs said: Nothing to do with sensor size. Agreed, as I have stated before... except maybe for the consideration that a lens is designed for a specific sensor/film size. 47 minutes ago, jcs said: Are you familiar with the scientific method? https://en.wikipedia.org/wiki/Scientific_method. Funny, I was thinking of asking the same of you. 47 minutes ago, jcs said: Your conjecture is as sensor size gets larger <insert specific properties which can be tested and characterized here>. Your Null Hypothesis is thus, "Sensor size has no effect by itself on the captured image". It's not sensor size... 47 minutes ago, jcs said: Now do your experiments using the scientific method. Instead of suggesting that someone do an experiment, perhaps it would be more expedient if you would simply respond directly to the points made in this forum. For instance, please explain how the equivalence principle and DOF calculation applies to the dramatic difference in focus roll-off between the two Fujinon 56mm lenses shot at identical f-stops. 47 minutes ago, jcs said: Do you own a camera and lenses? If not can you rent them? I only ask because you've never posted any of your own work. I do, and I have. In fact, my footage/images that I have posted in this forum were part of lens/camera/adapter tests. 47 minutes ago, jcs said: In your experiments you'll try your hardest to show that sensor size has no effect, eliminating as many variables as possible. Only after rigorous testing to try to eliminate sensor size as having an effect, can you then reject your null hypothesis and form a predictable theory which accurately describes the effects sensor size has on the captured image, and most importantly your new theory will be able to make predictions which can then be tested to further validate that your understanding of the system is correct. I predict that you will not directly address how the equivalence principle and DOF calculation applies to the dramatic difference in focus roll-off between the two Fujinon 56mm lenses shot at identical f-stops. Quote Link to comment Share on other sites More sharing options...
dhessel Posted April 10, 2017 Share Posted April 10, 2017 He already diid address it with the article he posted, "The Minolta/Sony Smooth Trans Focus 135mm f/2.8 [T4.5] lens, however, is a special lens design introduced in 1999, which accomplishes this by utilizing a concave neutral-gray tinted lens element as apodization filter, thereby producing a pleasant bokeh. The same optical effect can be achieved combining depth-of-field bracketing with multi exposure, as implemented in the Minolta Maxxum 7's STF function. In 2014, Fujifilm announced a lens utilizing a similar apodization filter in the Fujinon XF 56mm F1.2 R APD lens." If you point is that different lens designs can produce different looks then I think we all agree. If you point is the large format lens design produces their own large format look you will need to show examples of them and define what the properties are. noone 1 Quote Link to comment Share on other sites More sharing options...
jcs Posted April 10, 2017 Share Posted April 10, 2017 @tupp ok cool we are in agreement, sensor size has no effect by itself on the captured image, it's all due to optics alone. Quote Link to comment Share on other sites More sharing options...
dhessel Posted April 10, 2017 Share Posted April 10, 2017 Here is a rather bizzare and extreme example of how what lens design can do. http://www.rafcamera.com/en/elite-reverse-perspective-lens jcs and webrunner5 2 Quote Link to comment Share on other sites More sharing options...
tupp Posted April 10, 2017 Share Posted April 10, 2017 15 minutes ago, dhessel said: He already diid address it with the article he posted, "The Minolta/Sony Smooth Trans Focus 135mm f/2.8 [T4.5] lens, @jcs wrote that article? I missed it! Could you please provide a link to that article, and please quote the passage in which he addresses how the equivalence principle and DOF calculation applies to the dramatic difference in focus roll-off between 135mm apodization lens and other non-apodizatioin 135mm lenses? Thanks! Quote Link to comment Share on other sites More sharing options...
dhessel Posted April 10, 2017 Share Posted April 10, 2017 In 2014, Fujifilm announced a lens utilizing a similar apodization filter in the Fujinon XF 56mm F1.2 R APD lens." I never said he wrote it. Quote Link to comment Share on other sites More sharing options...
tupp Posted April 10, 2017 Share Posted April 10, 2017 14 minutes ago, dhessel said: If you point is the large format lens design produces their own large format look you will need to show examples of them and define what the properties are. I already have. The most obvious example so far is the "beer bottle" comparison. I have also listed what I think the properties might involve. 5 minutes ago, dhessel said: In 2014, Fujifilm announced a lens utilizing a similar apodization filter in the Fujinon XF 56mm F1.2 R APD lens." I think apodization filters appeared before your first example (1999). 8 minutes ago, dhessel said: Here is a rather bizzare and extreme example of how what lens design can do. http://www.rafcamera.com/en/elite-reverse-perspective-lens Never seen that one! Very cool! Thanks! 9 minutes ago, jcs said: @tupp ok cool we are in agreement, sensor size has no effect by itself on the captured image, it's all due to optics alone. Looks like my prediction was correct. Quote Link to comment Share on other sites More sharing options...
dhessel Posted April 10, 2017 Share Posted April 10, 2017 5 minutes ago, tupp said: I already have. The most obvious example so far is the "beer bottle" comparison. I have also listed what I think the properties might involve. I think apodization filters appeared before your first example (1999). The beer example shows the images are not exactly the same. It doesn't show what is uniquely different about all large format lenses nor have you stated what unique image characterists all large format images have in common that make them different than smaller. Irrelevant when the filter first appeared. The Fujinon uses one and that filter alters the Bokeh. 6 minutes ago, tupp said: Never seen that one! Very cool! Thanks! I hadn't either until recently, didn't even know something like that was even possible. It would be interesting to see how it could be used in the context of story. I think the point I and others are trying to make is that if you take a bunch of images shot with different lenses, sensor sizes and cameras that were shot at equivalence they would all look very much the same and identifying the large format images from the lot wouldn't be possible. noone 1 Quote Link to comment Share on other sites More sharing options...
tupp Posted April 10, 2017 Share Posted April 10, 2017 24 minutes ago, dhessel said: The beer example shows the images are not exactly the same. Uhm, those "beer bottle" images are very different. Did you enlarge them? Did you happen to notice the dramatic difference in focus on the bush/car to the left of the bottle? 24 minutes ago, dhessel said: It doesn't show what is uniquely different about all large format lenses nor have you stated what unique image characterists all large format images have in common that make them different than smaller. Well, in the first place, neither of those images were actually shot with a "large format" camera/lens. Right now, all we have to go on are comparisons made with FF, APS-C, M4/3 and an Iphone. In regards to optical and image properties that become increasingly inherent in bigger formats, I have in fact stated those earlier in this forum. 24 minutes ago, dhessel said: Irrelevant when the filter first appeared. Then why did you bother mentioning the Minolta/Sony lens with the date (1999) as well as the Fujinon APD with a date (2014)? 24 minutes ago, dhessel said: The Fujinon uses one and that filter alters the Bokeh. And your point is...? Note that the Fujinon 56mm comparison not only shows a dramatic difference in focus roll-off, but that that roll-off seems to be eating into the technical DOF range. 24 minutes ago, dhessel said: I think the point I and others are trying to make is that if you take a bunch of images shot with different lenses, sensor sizes and cameras that were shot at equivalence they would all look very much the same and identifying the large format images from the lot wouldn't be possible. I disagree. If you shot with a 20'x20' camera/lens and a S16 camera/lens, I think that most of us could tell the difference in an equivalence comparison. And my point with the dramatic apodization demo is that there is more to DOF and focus roll-off than merely the equivalence principle and the DOF calculation. There are other properties and variables involved. Quote Link to comment Share on other sites More sharing options...
dhessel Posted April 10, 2017 Share Posted April 10, 2017 16 minutes ago, tupp said: Then why did you bother mentioning the Minolta/Sony lens with the date (1999) as well as the Fujinon APD with a date (2014)? And your point is...? Note that the Fujinon 56mm comparison not only shows a dramatic difference in focus roll-off, but that that roll-off seems to be eating into the technical DOF range. I mentioned the Sony lens since it has the discription of what the APD filter does in that lens and that same type of filter was later used in the Fujinon lens. Point being that filter alters the DOF. I do see that mention DoF rolloff as one characteristic but I don't see any others. Quote Link to comment Share on other sites More sharing options...
fuzzynormal Posted April 10, 2017 Share Posted April 10, 2017 On 4/7/2017 at 2:05 PM, jcs said: There's no DOF advantage at all- we've covered this ad nauseum! ? What would a lens at that's 45mm F2.8 on a medium format camera need to be on a M43 cam in order to hit the same DOF equivalency? Or, how about a 80mm f1.9? Same question for those lenses to achieve similar DOF equiv. on a full-frame camera? Having exceptionally shallow DOF with a wide FOV while shooting motion pictures does create a cool effect. Kind of a 3D-separation-from-the-background-illusion...and then there's the subjective issue of bokeh --and also how big glass/focal plane light gets bent in that medium-format-way; as it needs to fall across a larger space. I don't know how to exactly explain it...is it sort of a parallax thing, maybe? Nikkor 1 Quote Link to comment Share on other sites More sharing options...
jcs Posted April 11, 2017 Share Posted April 11, 2017 1 hour ago, fuzzynormal said: What would a lens at that's 45mm F2.8 on a medium format camera need to be on a M43 cam in order to hit the same DOF equivalency? Or, how about a 80mm f1.9? Same question for those lenses to achieve similar DOF equiv. on a full-frame camera? Having exceptionally shallow DOF with a wide FOV while shooting motion pictures does create a cool effect. Kind of a 3D-separation-from-the-background-illusion...and then there's the subjective issue of bokeh --and also how big glass/focal plane light gets bent in that medium-format-way; as it needs to fall across a larger space. I don't know how to exactly explain it...is it sort of a parallax thing, maybe? Use the Equivalence math to compute the lenses and settings needed, or you can play with something like this: http://dofsimulator.net/en/ If you find cases where currently lenses don't exist, you can perhaps use focal reducers to create what you are looking for. The composite focal reducer + lens is a new lens. If you are asking do physically larger lenses have special properties, then you should be able to characterize those properties with math and physics. Meaning, as lens size grows, these properties change/increase in a predictable way from the math and physics. For example, a .1" diameter primary/external lens (to accomodate maximum aperture size) would have a small effect and a 10" diameter (to accomodate max. aperture) would have a large effect, with intermediate lenses behaving as predicted. So you could predict these properties with equations using the physical size of the maximum aperture diameter (and associated front lens size) as input to the output transfer function. However, in order to get equivalent FOV and DOF, a larger physical aperture has to move further away from the imaging plane (increased focal length), so we've just moved the aperture (and lens front) closer to the subject. If a generalized property of the glass was doing something interesting with photons based on physical scale, it should be possible to test the theory for which equations could be developed to make predictions and used in computer simulations etc. If so, after all these years why hasn't anyone done these tests? They would be very valuable to folks selling physically larger lenses (maximum aperture) if the properties were interesting, pleasing, etc. In any case an expert in glass/optics might have more insight. "DOF rolloff" isn't specific to lens size/scale but rather lens characteristics, such as using or acting like an apodization filter. Quote Link to comment Share on other sites More sharing options...
fuzzynormal Posted April 11, 2017 Share Posted April 11, 2017 http://dofsimulator.net/en/: More DOF with a wider FOV. That's kind of nice, right? So there is an advantage of shooting medium format video. Quote Link to comment Share on other sites More sharing options...
jcs Posted April 11, 2017 Share Posted April 11, 2017 14 minutes ago, fuzzynormal said: http://dofsimulator.net/en/: More DOF with a wider FOV. That's kind of nice, right? So there is an advantage of shooting medium format video. Sure it's an advantage if you don't have access to equivalent lenses in other formats. The Hasselblad H6D 100C has dramatic rolling shutter, probably better off using a focal reducer or equivalent lenses on a camera with less RS, right? Right now I'm only aware of the ARRI 65 providing decent video with native MF lenses. No one disputes that if one has access to lenses with special properties not available in other formats they are useful. For example if one has access to cheap vintage MF lenses but not modern fast FF lenses, a focal reducer can give new life to those MF lenses. Such a setup won't likely have the same level of quality as a modern fast FF lens, however the artifacts might be pleasingly artistic and useful. Quote Link to comment Share on other sites More sharing options...
fuzzynormal Posted April 11, 2017 Share Posted April 11, 2017 3 minutes ago, jcs said: Sure it's an advantage if you don't have access to equivalent lenses in other formats. That's why I asked about what it would take to have a M43 lens that shot the equiv. of a medium format 45mm@f2.8. Seems like that's not really possible, right? Quote Link to comment Share on other sites More sharing options...
jcs Posted April 11, 2017 Share Posted April 11, 2017 3 minutes ago, fuzzynormal said: That's why I asked about what it would take to have a M43 lens that shot the equiv. of a medium format 45mm@f2.8. Seems like that's not really possible, right? I don't know, do the math yourself and see. Quote Link to comment Share on other sites More sharing options...
tupp Posted April 11, 2017 Share Posted April 11, 2017 4 hours ago, dhessel said: I do see that mention DoF rolloff as one characteristic but I don't see any others. Are you referring to something that you saw in your aforementioned article? If so, please link it. If you are referring to the potential optical properties that might involve a "format specific" look, I listed some in the second paragraph of this post. In regards to the differences in "looks" between formats, other than focus rolloff, I listed some points in this post. 1 hour ago, jcs said: Right now I'm only aware of the ARRI 65 providing decent video with native MF lenses. There's also the Panavision DXL, along with its Red equivalent. There are some IMAX cameras that could probably use MF lenses. I believe that the second-generation Dalsa Origin had an MF sensor. The Kipon MF focal reducer works with several cameras. Of course, our own Rich Gale has the Forbes 70. Also, MF lenses work great on FF cameras with dumb (or tilt/shift) adapters. Quote Link to comment Share on other sites More sharing options...
jcs Posted April 11, 2017 Share Posted April 11, 2017 The Red Weapon 8K sensor is slightly wider than FF, and many FF lenses can be used: http://blog.abelcine.com/2015/07/23/red-weapon-8k-lens-options/. The Panavision DXL http://www.panavision.com/panavision-announces-new-large-format-digital-camera , while able to use MF lenses is still honestly marketed as a full frame sensor. For decent quality digital acquisition, I think the ARRI 65 is the only MF game in town right now. And again, the only reason they went that big was to re-use the ALEV III sensor and it's associated pixels and processing. Here Panavision's rep makes it clear he doesn't understand equivalence by not adjusting the aperture and ISO correctly (I hope this is not on purpose to sell large format products and services), Part 1 at 4:30: http://www.panavision.com/panalab-feature/large-format-lens-variations. The only reasons to use larger formats is resolution, bigger pixels, preservation of color science and image processing (ARRI 65), and available lens options (though for MF is quite limited compared to Super35, only a handful of lenses can be used with the ARRI 65). A quick search: didn't find any MF zoom lenses usable with the ARRI 65? Guess they use a teleconverter and adapter to use Super35 zooms on the ARRI 65 (reverse Speed Booster ). EDIT: there's at least 1, lol a 50-110 http://www.ibe-optics.com/en/portfolio-item/arri-alexa-65-optik/ and 8 primes. Quote Link to comment Share on other sites More sharing options...
noone Posted April 11, 2017 Share Posted April 11, 2017 2 hours ago, fuzzynormal said: That's why I asked about what it would take to have a M43 lens that shot the equiv. of a medium format 45mm@f2.8. Seems like that's not really possible, right? The medium format 45 2.8 would probably be doable, the MF 80 1.9 would probably not be (MAYBE the very fastest lens would be just possible). Of course, that 45 2.8 has infinite depth of field at 2.8 with a subject at around 15 meters or further. It would depend on the actual sensor "crop" as to what lens you would need. If it was .79x for instance to FF then that MF 45mm lens would be about a 36mm lens FF angle of view and therefore would need about an 18mm lens with M4/3. MF 2.8 would give DOF of about f2 FF, 1.4 APSC and about f1 with M4/3 so you should be able to do that maybe with something like a Sigma 18-35 1.8 and the faster speed booster. Wider and faster would be virtually impossible since the fastest lenses possible seem to be about the same regardless of sensor (or film) size though the wider you go the quicker you get infinity. A lens like even an 85 1.2 FF would not be likely in M4/3 Even a 24mm 1.4 FF lens which is readily available would need a 12mm f0.7 lens for equivalence (used wide open anyway). A lens like a FF 50 f0.95 lens would probably not be possible for normal photography to match. I love larger sensor cameras for being able to use slower lenses and yet still have decent subject isolation, for the "exotic" lenses (like 24 1.4 or 85 1.2) that can not or hardly be matched and especially for better low light performance. Smaller sensor cameras I like because they can be used with smaller lenses (not always) and especially for the different angle of view. Choice is great! jcs 1 Quote Link to comment Share on other sites More sharing options...
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