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hyalinejim

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  1. Like
    hyalinejim reacted to tupp in Is full frame really necessary?   
    I'll just repeat what has been mentioned in this thread.
     
    The lenses for the smaller formats have to use larger apertures to match the DOF of larger format lenses.  So, if one is shooting large format with shallow DOF (as in the above photo), matching that DOF with a with a smaller format lens will require its aperture to be wide open, which not only affects the overall sharpness (As you surmised), but it can also produce a difference in the relative sharpness between center and edges of the frame.  This characteristic with the smaller format lessens as the aperture is reduced.
     
    The above 8"x10" photo was shot with a roughly 600mm lens (not sure on the aperture), and the closet lens match that I could find in a smaller format is the Nokton 42.5mm f0.95 for M4/3.  Here is a test of that lens set at f.0.95 that not quite as close/tight as the above photo, but it gives a rough idea of how it might behave close and wide open.  It doesn't seem as sharp wide open as it does at smaller apertures, and, unfortunately, the DOF isn't quite shallow enough to match that of the above 8"x10" lens.
     
    In addition, at wider apertures,  there generally seems to be a faster transition from sharp to soft at the rear DOF limit on lenses made for larger formats.   This quality might relate to why the plane of focus seems more solid, more well-defined and flatter on larger formats.
     
    Also, the softness/bokeh outside of the DOF seems cleaner and less mushy.
     
    Here is a photo shot with an 8x10 camera that shows that shows a solid, flat focus plane (although the lens appears to be swung slightly to the right), with the subject nicely separating from the clean and not too mushy background.
  2. Like
    hyalinejim got a reaction from tupp in Is full frame really necessary?   
    Can you link to those posts?
    I'm still no clearer on what the differences in DOF rendering due to large/small format lenses actually looks like in an image.
  3. Thanks
    hyalinejim got a reaction from Rivhop in Magic Lantern 3.3k 16:9 RAW now with real time preview   
    https://www.magiclantern.fm/forum/index.php?topic=23041.msg216899#msg216899
    Background: user TheBilalFakhouri has unlocked correctly framed real time preview for EOS M and Danne has ported it to 5D3. Previously, Magic Lantern high res modes had a preview image that had either correct framing but in unusably slow frame rate black and white or real time colour preview with wrong framing. 
    Now, however there is high res, real time preview with correct framing.
    Kind of fun to try if you already own one of the supported cams 😁
  4. Like
    hyalinejim got a reaction from noone in Is full frame really necessary?   
    Can you link to those posts?
    I'm still no clearer on what the differences in DOF rendering due to large/small format lenses actually looks like in an image.
  5. Thanks
    hyalinejim got a reaction from Rivhop in Is full frame really necessary?   
    Well, I think that DOF as defined by circle of confusion etc can be matched because equivalence theory states that you can, if the lens for the smaller format is bright enough. However, I would expect to see a considerably softer image with lots of vignetting as you'd need a very fast lens to replicate the narrow DOF of this shot, and that's how lenses behave wide open. So although the DOF might be technically the same, the images will look different. But this is caused by the glass, not sensor size.
    And yes, the selection of lenses available for different formats is different. So your choice of format will have an impact on the look of the image. But I think a lot of people are making the point that those differences are derived from the glass and are not inherent to the sensor size.
    So theoretically, sensor size makes no difference to DOF. But in practice DOF is rendered qualitatively differently because the lenses are different / behave differently / must be set differently for different formats.
    If true, it's an interesting dichotomy. But it does suggest that any equivalence test is really just a comparison of two different lenses. In the same way that one of my 50mm lenses looks different from the other 50mm lenses I have for the same format. So would you agree that once you match focal length and aperture for the same shot on different formats, you're comparing lenses?
     
     
  6. Like
    hyalinejim got a reaction from tupp in Is full frame really necessary?   
    Actually, that's not quite the point I was making. I don't know much about large format lenses.
    My point was that any observed differences might be due to the difference in aperture required to maintain equivalence between formats. But I'm certainly open to the idea that there are other factors that also contribute. 
    Are there any conclusions you would draw on the pros and cons  of large formats versus small in terms of the qualities of images afforded by the glass associated with each? For example, are large format lenses well suited to narrow DOF pics that maintain sharpness and small format lenses well suited to deep DOF without suffering as much from diffraction?
  7. Like
    hyalinejim reacted to tupp in Is full frame really necessary?   
    Agreed (except for the smaller format having more vignetting), and I think that you have hit upon a prominent general difference between larger and smaller formats.  However, I think that there are other general differences between different sized formats.
     
     
    Of course, but, again, cropping into the image circle of a lens reduces the visible lines of resolution (which are related to focus/DOF).  So, a lens and it's format are integrated in that sense.
     
     
    Regarding points in this thread about lenses having their own particular look, many of those arguments are attempts to dismiss the idea that lenses made for larger formats generally share characteristics that are lacking in lenses made for smaller formats (and vice versa).
     
    Again, it is obvious that optical characteristics are inherent to the lens, but the camera lens and its format cannot be divorced without affecting the look/sharpness.
     
     
    Yes, unless one crops too severely into the image circle of a lens.
     
     
    Agreed.
     
     
    Not exactly.
     
    Of course, different lenses of the same focal length made for the same format can have differing looks/sharpness.  However, as you have noted, there are general characteristics inherent in lenses made for larger formats that are lacking in lenses designed for smaller formats (and vice versa).
  8. Like
    hyalinejim got a reaction from tupp in Is full frame really necessary?   
    I would say that this is very likely.
    It still sounds intriguing though 🙂 You misunderstood my proposed comparison though. The simulated crop on the 50 would simulate a notional sensor 1/4 the size of full frame. But I suspect that any differences observed would have more to do with the glass involved (and the necessary apertures) than the sensor size. Perhaps this is what accounts for your observation that the differences in rendering of DOF are greater when the disparity of sensor size is increased: to maintain equivalence, one lens is quite wide open and/or the other is quite stopped down.
  9. Like
    hyalinejim got a reaction from noone in Is full frame really necessary?   
    I would say that this is very likely.
    It still sounds intriguing though 🙂 You misunderstood my proposed comparison though. The simulated crop on the 50 would simulate a notional sensor 1/4 the size of full frame. But I suspect that any differences observed would have more to do with the glass involved (and the necessary apertures) than the sensor size. Perhaps this is what accounts for your observation that the differences in rendering of DOF are greater when the disparity of sensor size is increased: to maintain equivalence, one lens is quite wide open and/or the other is quite stopped down.
  10. Like
    hyalinejim got a reaction from tupp in Is full frame really necessary?   
    Well, you've convinced me that there's something worth considering there for sure. I had always conceived of the equivalence debates as being along the lines of flat-earthers etc 🤣
    But now I see that for some it's just about a level of complexity and possibly even bokeh connosseurship.
    For my purposes, these differences are so rarefied as to be irrelevant. However, the idea of testing for them is interesting. How about a test where you simulate a small sensor by using a center crop from a full frame stills camera? Like this:
    Full frame
    200mm, f7.1
    Simulated 4x crop sensor
    50mm, f1.8
    These would be different lenses. I could do this (when I have time) with a Canon 50 1.8 and Sigma 70-200 f2.8 and use ACR to correct for lens aberrations. Or instead with an OM Zuiko 50 1.8 and OM Zuiko 200mm f4 (possibly similar primes? But can't correct for aberrations)
    Would 4x be enough to show a difference?
    I realise you're dealing with a lower megapixel image from the central portion of a wide open lens for the simulated 4x so the image will be softer.  Would these variables make the test invalid?
  11. Like
    hyalinejim reacted to tupp in Is full frame really necessary?   
    The quotation marks that I employed imply something else.  I'm saying that refractive optical elements can affect focus and the focus range, and, additionally, that there are general tendencies, advantages and problems inherent in refractive optics designed for larger formats and likewise with refractive optics designed for smaller formats.  Of course, there are exceptions and some lenses for smaller formats possess some of the qualities generally found in larger format lenses, and vice versa.
     
     
    There is consistency, but there is also seems to be more than one variable at play, so there is some complexity.
     
    I would describe the look of larger formats as generally having a flatter and more "solid" focus plane with a faster "rolloff" at the DOF limits, but with a smoother and better resolved "macro-contrast" outside of the DOF limits.
     
     
    There is not a huge difference between FF and M4/3.
     
    Using a speedbooster or focal reducer can allow the qualities of the larger format optics to be captured on a smaller format.
     
     
    The dramatic discrepancies between the two images shown above are not due to any tendencies inherent in different sized formats.  My guess is that the DOF was not equivalently matched, plus the 1-inch camera likely had a built-in zoom lens (which can look/behave different than a prime) and excessive in-camera sharpening could have been enabled.
     
    There are a lot of variables that need to be controlled in such comparisons, otherwise the tests are invalid.
  12. Like
    hyalinejim got a reaction from tupp in Is full frame really necessary?   
    This implies that you maintain that there is a look inherent to a format, independent of variations between lenses. If so, it should be consistent as format size changes and it should be describable. How does the look of small format compare to the look of a larger format, at equivalent focal lengths and apertures?
    I'm just interested here, as I use DOF calculators to help my understanding when moving between FF, micro 4/3 and speedboosted micro 4/3. But I also see a huge difference in the images posted, which I would not have expected.
     
  13. Like
    hyalinejim got a reaction from tupp in Is full frame really necessary?   
    I certainly can see what you're talking about in the areas you've highlighted. It's very clear.
    But if you plug equivalent settings into a DOF calculator you get the same amount of DOF for both, according to the calculator. This is the theory, and it depends on certain assumptions regarding circle of confusion that I won't pretend I understand in depth.
    So is it fair to say that your position is something like this:
    "Even though DOF calculators show that the theoretical DOF of equivalent shots is the same, in practice there is an observable difference in how DOF is rendered between equivalent shots"?
    If so, and if I understand you correctly, that would mean that a DOF calculator is showing us 2 points on the DOF continuum, the point of near focus and the point of far focus, and these are the same for both formats if the focal length and aperture is equivalent. But it's not telling us anything about the DOF characteristics elsewhere on the continuum, which is noticeably different.
    That's certainly very interesting and worth investigating. I think for most people it's enough to know that they can match the field of view precisely using equivalence theory, and that the DOF is "the same" according to its assumptions. But others may notice and be very interested in differences in DOF behaviour that's not described by equivalence theory... if what you say is true! So we would be talking about a kind of DOF rolloff, which is shorter on larger formats and longer on small formats, according to equivalence sceptics.
    Is this understanding correct @tupp?
     
  14. Like
    hyalinejim reacted to Video Hummus in Sony A7C - harms the camera industry   
    It’s not surprising is it? Everybody wants full frame look, full frame low light, full frame image quality. Influencers scream it at the top of their lungs. “Great camera...but its not full frame.” So I’m not surprised at all. Sony asks a lot of money for their ASPC cameras. I’m not surprised they are moving their FF into smaller and smaller bodies.
    I recently picked up a used Pentax K1000 for cheap and bought some film and have really been loving it as an escape from the optimum capture settings mini-game we all play with these digital cameras.
  15. Haha
    hyalinejim got a reaction from Thpriest in Panasonic GH6 rumours   
    Good news in 2020???
    Is this a dream? 
  16. Haha
    hyalinejim reacted to kye in Panasonic GH6 rumours   
    Is this just fantasy?
    Lockdown in pandemic
    No escape from reality...
  17. Thanks
    hyalinejim reacted to hoodlum in Panasonic GH6 rumours   
    At 8:50 of this video posted today the GH5 successor is specifically mentioned to be in development.  
     
     
  18. Like
    hyalinejim got a reaction from kaylee in Magic Lantern 3.3k 16:9 RAW now with real time preview   
    https://www.magiclantern.fm/forum/index.php?topic=23041.msg216899#msg216899
    Background: user TheBilalFakhouri has unlocked correctly framed real time preview for EOS M and Danne has ported it to 5D3. Previously, Magic Lantern high res modes had a preview image that had either correct framing but in unusably slow frame rate black and white or real time colour preview with wrong framing. 
    Now, however there is high res, real time preview with correct framing.
    Kind of fun to try if you already own one of the supported cams 😁
  19. Like
    hyalinejim got a reaction from Rivhop in Magic Lantern 3.3k 16:9 RAW now with real time preview   
    One recent development that is of particular interest as @stephen mentions above is card spanning to CF and SD cards on the 5D3 to allow for higher write speeds, therefore higher resolutions and/or longer record times.
    I may have jumped the gun here though, claiming real time correct framing for the 5D3. 😳
    But if it brings people's attention to the fact that Magic Lantern is still alive and delivering the goods then that's a good thing I guess!
  20. Thanks
    hyalinejim reacted to stephen in Magic Lantern 3.3k 16:9 RAW now with real time preview   
    Yes did tested it, works great on Canon 5D Mark III. Really happy as 2:1 is my favorite aspect ratio. If one day real time live view in crop mode is fixed it would be truly a great Super35 RAW camera. Was thinking of selling my Canon 5D Mark III but now with latest development, no way it will stays with me. As one of the greatest DSLRs and great Super35 RAW camera too. 
    Same for EOS M -2.5K 2:1 and 2.8K at 2.35:1 ratios are now possible. Again if real time live view in crop mode is fixed it will be a great Super16 RAW camera. Much better resolution than first BMPCC at Super16. And EOS M is already a decent Super35 RAW camera  According to Bilal real time live view in crop mode will work also over HDMI. So external monitoring in crop modes will be possible too. 
    Cross my fingers this real time live view in crop mode make it to the builds soon. It will release also additional bandwidth for writing. It means stable and longer recording times in high resolution crop modes. 
    Really impressed with what ML (mostly Bilal and Danne the last 2 years)  have achieved with EOS M and Canon 5D Mark III !
    No 60fps and certainly not in high res crop mode. Only 45fps at 1080p. There are better cameras now for 60p. 
  21. Like
    hyalinejim reacted to Juan Melara in RED KOMODO 6K | First Footage - WOW   
    Got my hands on Red Komodo to test for a few days. I'm impressed.



    A few more images can be seen here: https://imgur.com/a/HAWFShe
     
  22. Like
    hyalinejim got a reaction from PannySVHS in Magic Lantern 3.3k 16:9 RAW now with real time preview   
    One recent development that is of particular interest as @stephen mentions above is card spanning to CF and SD cards on the 5D3 to allow for higher write speeds, therefore higher resolutions and/or longer record times.
    I may have jumped the gun here though, claiming real time correct framing for the 5D3. 😳
    But if it brings people's attention to the fact that Magic Lantern is still alive and delivering the goods then that's a good thing I guess!
  23. Like
    hyalinejim got a reaction from tupp in Magic Lantern 3.3k 16:9 RAW now with real time preview   
    https://www.magiclantern.fm/forum/index.php?topic=23041.msg216899#msg216899
    Background: user TheBilalFakhouri has unlocked correctly framed real time preview for EOS M and Danne has ported it to 5D3. Previously, Magic Lantern high res modes had a preview image that had either correct framing but in unusably slow frame rate black and white or real time colour preview with wrong framing. 
    Now, however there is high res, real time preview with correct framing.
    Kind of fun to try if you already own one of the supported cams 😁
  24. Thanks
    hyalinejim got a reaction from Avenger 2.0 in Magic Lantern 3.3k 16:9 RAW now with real time preview   
    https://www.magiclantern.fm/forum/index.php?topic=23041.msg216899#msg216899
    Background: user TheBilalFakhouri has unlocked correctly framed real time preview for EOS M and Danne has ported it to 5D3. Previously, Magic Lantern high res modes had a preview image that had either correct framing but in unusably slow frame rate black and white or real time colour preview with wrong framing. 
    Now, however there is high res, real time preview with correct framing.
    Kind of fun to try if you already own one of the supported cams 😁
  25. Like
    hyalinejim got a reaction from filmmakereu in Magic Lantern 3.3k 16:9 RAW now with real time preview   
    https://www.magiclantern.fm/forum/index.php?topic=23041.msg216899#msg216899
    Background: user TheBilalFakhouri has unlocked correctly framed real time preview for EOS M and Danne has ported it to 5D3. Previously, Magic Lantern high res modes had a preview image that had either correct framing but in unusably slow frame rate black and white or real time colour preview with wrong framing. 
    Now, however there is high res, real time preview with correct framing.
    Kind of fun to try if you already own one of the supported cams 😁
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