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tupp

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Everything posted by tupp

  1. There are three ways that mplayer could work in this scenario: it can play the video playback/live stream from the camera (given that the camera playback/live stream is the desired fps); it can play the file directly off the camera at the fps specified in the mplayer command (given that the destination device can mount the camera's storage); it can play the file from the destination device, as it is being transferred to (or stream-captured to) the destination device (at the original fps or slower); I have just tested the last method by playing (at 24 fps) a Canon 60 fps MOV file off of a USB pen drive as was being transferred to the pen drive. Not sure if it will work with every codec/container. I misread the requirement of a "box." I thought that the box was intended as a "controller box" to enable the instant slow-mo -- not that the box was a "photo booth." Now that I understand what you are trying to do, I think there might be better camera alternatives if you are not locked into getting a GH5 or using your A7's. For instance, it would probably be easier to just use a machine vision camera that was constantly streaming and merely record/capture and playback that stream, with a button (or two) that starts/stops the right scripts. The real challenge might be devising a usable and appropriate interface. Are there any prior examples of a slow-mo photo booth?
  2. @BTM_Pix Mplayer can play a file on the destination device while the file is being transferred from the camera to the destination device. So, if the video file is the right container/codec, a simple script would enable slo-mo playback with mplayer, by starting a transfer and then starting the mplayer playback at the specified frame rate. This method should work with both USB and wifi file transfers. Looking forward to hearing your solution!
  3. @Alpicat Thanks for all the updates and videos! At some point, I hope that someone will create a simple tutorial demonstrating how to configure the EOSM with ML to enable these capabilities.
  4. Getting deeper and deeper into the age of instant gratification... It probably doesn't require a lot of processing power to simply slow down the frame rate -- it just takes a buffer/storage to hold the faster playback stream from the camera. Mplayer can play a stream from some video files while the file is being stored/created. Here is an example of how to play the frames of a video file at a frame rate of 23.97 (regardless of the original frame rate): I think that ffplay (the ffmpeg player) can do the same, but I am not too familiar with it.
  5. @Alpicat Thanks for the videos and for the link to Juan Melara's page!
  6. Yes, but smudging grease on your lens will simultaneously make the focused foreground softer, so doing so doesn't really affect DOF as much as it affects the overall focus. On the other hand, an APD filter will not make the focused foreground softer while it does make the bokeh/background softer (than what is expected by the DOF formula). So, there exist variables other than those in the DOF formula that affect DOF. By the way, never put grease on your lens -- instead, do so on a clear/UV filter.
  7. That's good to know. Isn't there some bit depth mode of 9-11 bits? If so, I wonder if that would give a better, continuous image than 10 bit. I actually read about this in the ML thread. I assume that a Sandisk Extreme Pro works without running the tests. By the way, I was at the Cinegear trade show two days ago, and both Sandisk and Kingston had a booth. I told both of them that ML folks are starting to overclock cards, significantly increasing the write speeds. I suggested that they should consider designing cards meant for overclocking. Neither company had heard of ML nor card overclocking, but they seemed interested. It looks great! Thanks for all of your tests! Seeing people in the frame definitely helps. The dynamic range looks wide, but it seems like there might have been open sky (and/or a white building) behind the camera. So, you format this card in the camera with an exfat filesystem? Do you install ML with this 64GB, exfat card to give the card the boot flag, or do you use some other program to do so? Thanks!
  8. tupp

    Cinegear 2018

    The speed booster was also made by White Point. The combination yielded nice look.
  9. tupp

    Cinegear 2018

    Sorry, I meant to say that the Schneider swing lens has a Sony E-mount.
  10. tupp

    Cinegear 2018

    Saw a few interesting things. Zeiss has unveiled six of their Supreme Primes. A new snorkel company has appeared, and the lenses look pretty good for what they are. Band Pro has one of the White Point rehoused Blad lenses with a speed booster on a camera, and it is pretty. Schneider is showing their swing lenses with a PL mount, which was new to me. OSRAM has on display their HMI STUDIO tungsten-balanced HMI bulbs. Didn't see much new in regards to cameras.
  11. tupp

    Cinegear 2018

    It just started about 45 minutes ago. Will be heading to the show soon.
  12. 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?
  13. 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.
  14. 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).
  15. @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.
  16. 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.
  17. 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.
  18. 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.
  19. 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.
  20. Have we already discussed this camera?
  21. 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.
  22. 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.
  23. 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.
  24. 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."
  25. 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).
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