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tupp

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Everything posted by tupp

  1. Nevertheless, it is a fact that the background is softer with the APD filter in every set of the comparisons that I linked, except for the set with the smallest aperture (f5.6). You are grasping at straws. Really? Please explain how the equivalency formula accounts for the effects of a gradated aperture. Additionally, please explain how the formula accounts for the combined effects of a gradated aperture and a variable iris separated by some distance within an optical system. Huh? Is this some sort of physics metaphor involving Einstein and Newton?
  2. If an apodization filter works like an aperture but with a gradated edge, then I would agree that it decreases the overall apparent aperture (as long as the mechanical iris is larger). However, that gradation of the aperture edge is affecting DOF, and the character of that gradation (combined with the mechanical iris) is one of several variables ignored by the equivalency formula. Ha! If he screwed up the focus/distance, then he did so in every comparison except for the f1.4 set and the f5.6 set. In every case except for the 5.6 set, the APD bokeh has a softer edge, as is expected. In addition, the bokeh progressively gets smaller with each lens as it is stopped down, which is also expected. On the other hand, the background is softer with the APD filter in every set except for the one at f5.6. So, I am not sure if he screwed up the tests or if such results are peculiar to using a gradated aperture along with a hard-edged aperture. It sounds like such a filter would easy to make/airbrush. It's essentially a radial gradation filter. It could also just be an opaque disk with a large center hole, with progressively smaller holes radiating outward.
  3. I still dont understand what you want to prove.  Well, I have demonstrated that the equivalency principle doesn't take into account all of the variables that affect DOF and focus, therefore it is not absolute. 😊 Yep. I acknowledged that very point above. However, that point is irrelevant to the DOF equivalence discussion, and the validity of equivalence is the primary gist of OP's article from which this entire thread follows I mostly agree, but I would add that images from lenses designed for larger formats often look different than images from lenses designed for smaller formats using "equivalent" settings. The lens for the larger format has strikingly shallower DOF. It's amazing that some can't see that. Again, the differences between the two images is striking. Also, it is often the subtleties that make the difference in imaging. In regards to the lenses of the two images in question: the focal length is an exact match; the aperture is an exact match; the refractive optical elements are identical; the only difference is that one lens has a non-refractive filter. How can you reconcile the equivalency principle with such a dramatic difference in DOF, when the aperture and focal length are the same? Please show how the equivalence math accounts for the dramatic DOF difference in the apodization example that I posted above. So, you maintain that an equivalence comparison in which all images were shot with the same zoom lens proves that there is no difference in look/DOF between optics designed to cover different sized formats? Doesn't one need to compare optics designed to cover different sized formats to make a valid conclusion on whether or not formats have a certain look? In regards to the "countless other" equivalency tests, most of them have been discussed on this forum, with the equivalency "absolutionists" similarly glossing over little "details," such as comparisons done with the same zoom lens. In almost every such test that used lenses made for different formats (except for a peculiar one linked earlier in this thread), the larger format lens always has shallower DOF. In addition, another common flaw in equivalency tests is that there is nothing but air between the foreground and background, so there is no way to tell how the DOF rolls off. No. The whole point of that apodization demonstration is that the aperture and focal length are EXACTLY identical -- but the DOF is very different. If you click-to-enlarge the photos, you will see considerably more DOF differences than those shown in just the upper right corner. By the way, that apodization example originated in this article. I think that apodization filters are always internal in a lens. I believe that Fuji had a lens in which different apodization filters could be inserted. The formula only gives the "mathematical" DOF. It does not account for DOF rolloff nor for the mushiness at wider apertures with smaller format lenses (nor for apodization).
  4. @no_connection The equivalency principle is not absolute if it doesn't work in every instance. You seem to agree that it does not work in every instance. So far, almost all equivalency tests show significant differences between the look from lenses designed for different formats, with the results mostly showing shallower DOF and less mushy focus falloff with larger format lenses. None of these tests are "pushing the extreme." There exist variables other than focal length and aperture (and aberration) that affect DOF and focus falloff. You and others in this thread touched on one such variable -- there is a limit to the amount of optical resolution that can be crammed into an image circle for a tiny sensor. Like many physical properties, this variable probably doesn't have a hard threshold, but instead is a matter of degree, with the image slowly degrading as the image circle decreases. There are plenty of other possible variables, too. If you think that the only variables that matter are the ones expressed in the equivalency principle (focal length and aperture) and aberration, merely consider apodization optics. Here are two photos taken with two Fuji lenses of the same focal length and set to the same aperture, with identical optical elements, except one of the lenses includes an apodization filter: Note the discrepancy in the softness of the distant background (click on the photos to enlarge them). Every variable is identical between these two shots, except that one lens contains a filter, and yet there is an obvious difference in the DOF. The equivalency formula does not take into account all of the variables that affect focus and DOF, therefore it is not absolute.
  5. Marvelous mister, you completely missed the quote in my message which showed that I was merely responding to another poster who suggested that one could not "tell the cameras apart." Sm-o-o-o-o-o-th! The striking differences between the two images do not involve the character of particular lens brands -- the discrepancies shown result from fundamental differences in DOF/focus. Actually, I am not sure that I could say which lens was a Voigtlaender or a Sony, because I am not familiar with either brand. On the other hand, I would guess that the Sony lens is a FF lens and that the Voigtlaender is made for 4/3. If so, the photo with shallower DOF is probably from the larger format (Sony?) lens, because such has been the case in every equivalency test so far (except for a peculiar one linked earlier in this thread). A lot of folks in this forum insists that the equivalency principle is absolute -- that lenses made for differing formats will look exactly the same, given the proper apertures and focal lengths. Evidently, you disagree that the equivalency principle is absolute, as your sarcasm indicates that the difference is obvious between these two lenses which are designed for different formats. I mostly agree, but that point is irrelevant to whether or not the equivalency principle is valid.
  6. From this thread's excellent EOSD article: This paragraph suggests that equivalence principle is completely true -- in other words, that there is no difference between the looks from different sized formats (more importantly, no difference in the looks from the optics designed for different sized formats). From the most recent excellent EOSD article on the Fuji GFX 50S: This passage asserts that there is a difference in looks between formats, due to the "mushiness" inherent in having to use larger apertures with smaller format lenses, in order to get the same mathematical DOF as that of lenses made for larger formats. In other words, the equivalence principle is not valid, and optics for different sized formats yield differing looks. It seems confusing... The differences between the two images are significant. I can tell them apart, and it appears that another poster in this thread can also discern the differences.
  7. Great footage (and music)! Thanks! Interesting. The tests are required every time one starts the camera? 1800x1030 works for me. What's the longest run time you've achieved with that mode? I've heard some good things about the Viltrox focal reducers. I have the RJ focal reducer for the EOSM with a Nikkor mount, and it was used in a couple of the shots in this test (along with the 18mm-55mm kit lens): All of this footage employs the All-I frames video hack in a Magic Lantern build from 2015. Frame rates were 23.98 fps and 59.94fps (yielding 1280x720 which was scaled up to 1920x1080). The Flaat 10 picture style was used in all shots with the first shot ungraded, but I gave a touch more snap to the contrast of the rest of the clips. The ISO was set to 800, but noise was prominent in some footage. So, I'll probably dial the ISO back down to 100 or 200 when possible. The bit rate was boosted to 1.5x, but I got a hiccup (dropped frame or doubled frames) four seconds into one of the shots. So, regardless of the cause, I will probably back off of that setting and bring the bit rate down to 1.3x in subsequent shoots. A screw-in ND and a polarizer were stacked, so. occasionally, there was slight vignetting. However, there was some weirdness with the vignetting moving/changing in the middle of shots, which could be attributed to OIS, except that same behavior seemed to appear in the shots with the manual Nikkor 20mm with the RJ focal reducer. Have to take a closer look at this apparent phenomenon. Anyone have ideas on the cause? This test was rushed, and I forgot to change the shutter speed from 1/60th to 1/120th in the first 60fps (slo-mo) shot, so that clip looks slightly smeary. I see a little moire/aliasing and a moment of banding, but I think that this imaging quality could work for a lot of situations.
  8. The photo of the Fran certainly looks like the Ximea camera from the front. Good find! On the other hand, the specs don't seem to perfectly match. Judging from Cinemartin's rough sketch, perhaps they are taking the innards of the Ximea and putting them in a different box, with some hardware/software mods. I wasn't aware that there is such bigotry against those of the Spanish "race." Not familiar with Cinemartin, but a lot of the stuff that get's touted on this forum is re-branded product.
  9. Have we already discussed this camera?
  10. The configuration that I suggested above (with the smart, reinforced M4/3-to-EF adapter) does not preclude the clueless EF lens user market... nor does it preclude any market. In fact, such a smart, reinforced adapter configuration allows the most versatility in regards to marketing, without any sacrifice to the EF lens market.
  11. Yes. I read that, but that makes even less sense than BMD and Panasonic offering only EF mounts (or longer) for their S35 cameras. What if somebody wants to use a M4/3 lens on the Yongnuo M4/3 camera? or, what if somebody wants to use a speed booster, tilt-shift adapter, c-mount lens, etc. on the Yongnuo M4/3 camera? All they have to do to easily solve those dilemmas (and probably sell more cameras) is to start with a M4/3 mount and supply the camera with a smart, reinforced M4/3-to-EF adapter... and the camera will still take the Yongnuo lenses.
  12. Reminiscent of the Olympus Air or the Sony QX, which are linked in your article along with a couple of other similar concepts from Kodak and DxO. Can't understand why they decided on an EF mount for a M4/3 camera, but it seems like many camera manufacturers wear blinders when it comes to considering any lens mount other than EF.
  13. The AC adapter delivers 9V. If there is no voltage regulator inside the "dummy" battery, then the camera is running off of a 9V supply. If the there is a voltage regulator in the dummy battery, then the camera is likely running off of ~7.2V. Either way, there is likely extra heat being generated inside the camera (compared to merely running off of a 7.2V internal battery), which could result in extra noise. Best to keep everything inside the camera at nominal voltage. Not familiar with "QC."
  14. I see it. Yes, batteries' voltage is higher when fully charged. So, likewise, if you start with a fully charged 9V battery (as opposed to a 7.2V battery), you will probably see voltages higher than 9V -- significantly higher than the 8.4V peak of the fully charged internal battery. Again, it's a good idea to start with an external battery that has the same voltage as the unregulated internal battery. Thus, you know that you have enough voltage for the camera to properly function, while you will not be unduly increasing the camera's internal temperature (possibly causing extra noise).
  15. Are you sure that DC power supply is made by Fuji? Or maybe the camera just runs hot and noisy when powered by 9V. The voltage of the X-h1's internal battery is definitely 7.2V. I would avoid running any camera at a voltage higher than that of its internal battery.
  16. Crop factor works on fixed lens systems just like it does with interchangeable lenses -- the difference is that you merely have one possible lens with a fixed system. Panasonic (and Leica) list the 10.9mm-34mm zoom as a 24mm-75mm FF equivalent. So, the crop factor is built-in to (an can be determined from) those two given ranges.
  17. Interesting... so does that mean that the lens on the Leica D-Lux (typ 109) is actually designed and made by Panasonic? I don't think that flange focal distance applies to cameras with fixed lenses -- there's no flange. At any rate, the only physical limits in converting that glass to an outboard M4/3 lens is for the rear optical elements (and their barrel) to clear the M4/3 throat and for those elements to not make contact with a camera's shutter. That makes sense, but the crop factor on the LX100 is 2.2 -- just slightly more than M4/3. The difference between 16MP and 12.7MP seems to be more significant than the slight difference in crop factor between the LX100 and M4/3.
  18. Not sure why Leica couldn't make an outboard version of their fixed zoom on the Panasonic LX100. It is fast, sharp, and it has a nice zoom range -- and it covers a 4/3 sensor.
  19. It was full HD. I think that the sharpness of the lens, combined with the subject distance and the fineness of the wood texture made for a "perfect storm." However, I have made some more tests, which I will try to post soon, and there was also moire problems with some coarse fabric. This is an amazing capability for such an inexpensive camera! Thanks for sharing! I've got to get some S16 lenses, or try the BMPCC speed booster (if/when the Photodiox M4/3 to EF-M adapter appears). By the way, I tested it, and one can't shoot video with a manual lens while the "Release shutter without lens" is disabled -- so one might have to be careful not to press the shutter button when using the BMPCC speed booster on the EOSM. Oh, that's a bummer. Hope someone finds a way around that. The thing is, I would be happy with just 1920x1080 and less overclocking.
  20. The batteries for the X-h1 are probably 7.2 volts, so it's best to supply your camera with that voltage. So, it might be good to consider using readily available and inexpensive, 7.2 volt Sony NP batteries (which come in various sizes/capacities). You can connect them to your CP-W126 cable with an NP battery plate. Here is a tutorial on powering a camera with these items.
  21. Here are a few seconds (30MB MOV file) shot on the EOSM with the more recent ALL-I hack enabled and with bitrate boosted 1.5x: MVI_5681-short.mov The frames are definitely all I-frames. However, as you can see, moire was problematic with the back wall and with the lens that I was using -- the Pixco Mini 25mm F1.8 APS-C lens ($25 when I bought it last year). Sorry for the shaking, but the Pixco has no stabilization. I am going to start trying to boost the bitrate, but I also want to try recent, stock ML builds and just boosting bitrate to 2.5 to see if that makes any difference. I especially want to try 60 fps.
  22. I don't think OP was objecting to phones because he/she is worried about busted takes -- he/she seems to expect crew to "look busy."
  23. Very informative and helpful! Thanks! Very nice! Thank you for posting their videos! Yes. It is an amazing little bargain camera, and it is so versatile with the EF-M mount and ML. Thanks for posting the Ryan Moorman 4:3 video. @dfort on the ML forums has directed me on how to get a build with ALL-I working, and I have already installed it and enabled ALL-I and set the bitrate to 1.5x. Testing soon, and if I don't get any glitches, I will try to gradually boost the bitrate until the video breaks. Will posts the test results as soon as I am able.
  24. I don't think so. In addition, it is often helpful for crew to be connected to the world outside the set, as, for instance, they might be expecting delivery of gear/expendables or waiting on the arrival of other crew, or if they are consulting a technical expert on a new piece of gear outside the set, etc. Are you certain that they have not consolidated gear nor prepped for the next shot? With pro crews, a lot of that work is built-in to the process and is muscle memory. Would you rather have pros who do their job without thinking and who, consequently, have free time to deal with any unexpected eventualities, or would you rather have inexperienced crew who must constantly focus on every detail and might miss something important or strike out when thrown a curve? If you are genuinely concerned about whether or not they are prepped for the next shot, you can merely have your AD remind the department heads what's coming next. If you do so, you will probably find out that the crew is several steps ahead of you. By the way, consolidation of gear is usually automatic and built-in, because it it makes the work much easier for the crew and makes it easy to deal with unexpected problems, and, most importantly, wrap goes much faster! If you see a pro crew sitting around on their phones or twiddling their thumbs, it's probably because everything is done, dressed, staged and prepped, and they are waiting for the department head to give them their next order -- it's usually a good sign. Also, if there are any sudden, unexpected changes, there is a free pro crew on hand to roll with the punches.
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