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Everything posted by tupp

  1. If no frames were discarded in any of the frame rate changes, the end result is identical to slowing down 119.88 fps footage to 23.976 fps. However, it sounds like your NLE may have converted 59.97 fps to 23.976 fps without changing the speed of the content. In that case, your apparent slowing would be just 1/2 of normal speed -- equivalent to running 119.88 fps footage at 59.97 fps.
  2. Ha! Try a Technovision Mk III on your monopod!
  3. tupp

    Slowing down 24p

    Yes. That is why I said this:
  4. Yes. A monopod is better than my suggestion of a tripod center column and head. A monopod can telescope to different heights and a full tripod head isn't needed for this rig. By the way, I think that such a rig was called a "belt pod."
  5. tupp

    Slowing down 24p

    In the film days, I under-cranked the camera on a couple projects. It's a dramatic effect that sort of "feels" slow motion, but it is not the same as slowing the frame rate in post.
  6. Try a "belt pole" rig: If you have a lightweight tripod with a center column, you can try using the center column with the head and make a belt with a pouch. It won't have an adjustable height, but it might put the camera close to where you need it, and you will get a rough idea of how stable such a rig can be. A shoulder bracket is not necessary, but it allows one to let go of the camera.
  7. I catch glimpses of some fairly deep colors in this recent video shot on an EOSM. No details are given in the description, but it could have been captured at 14 bits raw. I think it would look fine without the fake grain, film gate and sprocket hole.
  8. Better late than never... Here is a three second clip from a test shoot of the E-M10 III, with the camera's Highlight and Shadow control set to : -1 highlights; 0 mids; and +1 shadows. Here is a coarsely graded video using the rest of the test footage from that session.
  9. I don't know... footage from the F35 looks really good. Frame rate and "motion cadence" are significant properties in making video look like film.
  10. LOL! Well, I think that some of the images that I linked were actually shot on Ektachrome and Kodacolor, but I mostly gave Kodachrome examples, as it is the "extreme" of the color emulsions. Also, I said early in the thread that color depth was probably the key variable for digital "thickness," so I agree that "dense" digital images can be (and have been) achieved with digital cameras. Both trailers look good, but the Red footage looks thin/brittle compared to that of the Alexa footage. Of course, much of these looks could result from the grade.
  11. Yes. Anything that narrows the field of view increases "telephoto" compression. So, cropping into a frame increases telephoto compression.
  12. Ha, ha! Great performances! What is the "12-step program" for B-roll addicts?
  13. If the goal is to convert batches of images from raw to jpeg, there are many free, open-source apps that do so. Darktable, RawTherapee and and Photivo are powerful raw image developing applications. Digikam is a less powerful photo management program, but it can do batch conversions. ImageMagick batch converts raw to jpeg. It has a GUI, but most use it on the command line for speed. If you are not trying to do anything fancy in your batch conversions, a simple ImageMagick terminal command is probably the quickest and easiest way to go.
  14. It doesn't look "thicker" to me -- just wetter, causing different colors and, in this case, more contrast. If you shot either scene (dry or wet) on Kodachrome, it would look significantly thicker. Also, the difference in the pattern of dappled light skews the comparison. One can't help but wonder how this test would appear with an overcast sky. That's some exceedingly coarse grain in the images of those charts. Huge grain like that significantly reduces color depth, which affects the look of the charts and throws-off the comparison a little. That's one way to describe it. Another way put it is that, due to the initial underexposure, more of the values from dark-tones to mid-tones are compressed together at the bottom end (along with the base fog). So, when the exposure is boosted to restore the mid-tones to their normal value, the dark tones become brighter than usual, because they remain compressed close to the mid-tones. I am not sure what this exposure comparison adds to the idea that the brighter tones in film emulsions generally are less saturated (with the darker tones being relatively more saturated, by default). I agree partially -- I think that there are other variables involved in how film renders color. For instance, film generally has more color depth than digital. I disagree. A lot depends on the emulsion. I think that one would see a dramatic difference comparing Kodachrome to digital. Typical print film would yield less of a difference.
  15. Yes, but it is less light on a proportionally smaller area. So, cropping-in on an image circle doesn't change the exposure.
  16. Although we disagree on the "less than 8-bit" images, I have been waiting for someone to mention that we are viewing film emulsion images through 8-bit files. To the eye, the color depth of Kodachrome is considerably more vast than what is shown in these 8-bit images. Kodachrome was one of the rare film processes that added dye to the emulsion during processing, which gave it such deep colors (and which is also more archival). Some of that splendor is captured in these 8-bit scans, so, theoretically, there should be a way to duplicate those captured colors shooting digitally and outputting to 8-bit. You probably would see the variation in the skin tones if you were there, but, to one's eyes, such variations don't seem so dramatic. Furthermore, Kodachrome usually looked snappier than other reversal films (when normally processed), but when directly viewing a Kodachrome slide, it won't look as contrasty as the 8-bit scans we see in this thread. Of course, the baby's face (and the parents' faces) is brighter on the front, because of the lighting angle. If the baby has been sunbathing for hours, then the father is crispier than George Hamilton.
  17. To me, the "thickness" of a film image is revealed by a rich, complex color(s). That color is not necessarily saturated nor dark. That "thickness" of film emulsion has nothing to do with lighting nor with what is showing in the image. Certainly, for the thickness to be revealed, there has to be some object in the frame that reflects a complex color. An image of a white wall will not fully utilize the color depth of an imaging system. However, a small, single color swatch within a mostly neutral image can certainly demonstrate "thickness." I don't think that's how it works. Of course, there is also reversal film. Agreed. Digital tends to make skin tones mushy (plastic?) compared to film. Look at the complex skin tones in some of these Kodachrome images. There is a lot going on in those skin tones that would be lost with most digital cameras. In addition, observe the richness and complexity of the colors on the inanimate objects. Yes. Please note that most of the images in the above linked gallery are brightly lit and/or shot during broad daylight. Agreed. I think that the quality that you seek is inherent in film emulsion, and that quality exists regardless of lighting and regardless of the overall brightness/darkness of an image. Because of the extensive color depth and the distinctive color rendering of normal film emulsion, variations in tone are often more apparent with film. Not sure if that should be considered to be more of a gradual transition in chroma/luma or to be just higher "color resolution." Those images are nice, but they seem thinner than the Kodachrome images in the linked gallery above. The image is nicely crafted, but I read that it was shot on Fuji Eterna stock. Nevertheless, to me its colors look "thinner" than those shown in this in this Kodachrome gallery. Great site! Thanks for the link! I disagree. I think that the "thickness" of film is inherent in how emulsion renders color. The cross-lighting in that "Grandmaster" image seems hard and contrasty to me (which can reveal texture more readily than a softer source). I don't see many smooth gradations/chirascuro. Evidently, OP seeks the "thickness" that is inherent in film emulsion, regardless of lighting and contrast. Nice shots! Images from CCD cameras such as the Digital Bolex generally seem to have "thicker" color than their CMOS counterparts. However, even CCD cameras don't seem to have the same level of thickness as many film emulsions. That certainly is a pretty image. Keep in mind that higher resolution begets more color depth in an image. Furthermore, if your image was shot with Blackmagic Ursa Min 12K, that sensor is supposedly RGBW (with perhaps a little too much "W"), which probably yields nicer colors.
  18. Of course, a lot of home weren't properly exposed and showed scenes with huge contrast range that the emulsion couldn't handle. However, I did find some examples that have decent exposure and aren't too faded. Here's one from the 1940's showing showing a fairly deep blue, red and yellow, and then showing a rich color on a car. Thick greens here, and later a brief moment showing solid reds, and some rich cyan and indigo. Unfortunately, someone added a fake gate with a big hair. A lot of contrast in these shots, but the substantial warm greens and warm skin and wood shine, plus one of the later shots with a better "white balance" shows a nice, complex blue on the eldest child's clothes. Here is a musical gallery of Kodachrome stills. Much less fading here. I'd like to see these colors duplicated in digital imaging. Please note that Paul Simon's "Kodachrome" lyrics don't exactly refer to the emulsion! OP's original question concerns getting a certain color richness that is inherent in most film stocks but absent from most digital systems. It doesn't involve lighting, per se, although there has to be enough light to get a good exposure and there can't be to much contrast in the scene. We have no idea if OP's simulated images are close to how they should actually appear, because 80%-90% of the pixels in those images fall outside of the values dictated by the simulated bit depth. No conclusions can be drawn from those images. By the way, I agree that banding is not the most crucial consideration here -- banding is just a posterization artifact to which lower bit depths are more susceptible. I maintain that color depth is the primary element of the film "thickness" in question.
  19. Well, when I listed the film "thickness" property of "lower saturation in the brighter areas," naturally, that means that the lower values have more saturation. I think that one of those linked articles mentioned the tendency that film emulsions generally have more saturation at and below middle values. Thanks for posting the comparisons! Then what explains the strong "thickness" of terribly framed and badly lit home movies that were shot on Kodachrome 64? Unfortunately, @kye's images are significantly flawed, and they do not actually simulate the claimed bit-depths. No conclusions can be made from them. By the way, bit depth is not color depth.
  20. Thank you for posting these Trueclor tests, but these images are not relevant to the fact that the "4.5-bit" image that you posted earlier is flawed and is in no way conclusive proof that "4.5-bit" images can closely approximate 8-bit images. On the other hand, after examining your 2-bit Truecolor test, it indicates that there is a problem in your rounding code and/or your imaging pipeline. 2-bit RGB can produce 64 colors, including black, white and two evenly spaced neutral grays. There seem to be significantly fewer than 64 colors. Furthermore, some of the adjacent color patches blend with each other in a somewhat irregular way, instead of forming the orderly, clearly defined and well separated pattern of colors that a 2-bit RGB system should produce with that test chart. In addition, there is only one neutral gray shade rendered, when there should be two different grays. Looking at the histogram of the 2-bit Truecolor image shows three "spikes" when there should be four with a 2-bit image: Your 2-bit simulation is actually 1.5 bit simulation (with other problems). So, your "rounding" code could have a bug. Well, something is going wrong, and I am not sure if it's compression. I think that PNG images can exported without compression, so it might be good to post uncompressed PNG's from now on, to eliminate that variable. Another thing that would help is if you would stick to the bit depths in question -- 8-bit and "4.5-bit." All of this bouncing around to various bit depths just further complicates the comparisons.
  21. Not all additive color mixing works the same. Likewise, not all subtractive color mixing works the same. However, you might be correct generally in regards to film vs. digital. One has to allow for the boosted levels in each emulsion layer that counter the subtractive effects. I don't think the scopes are mistaken, but your single trace histogram makes it difficult to discern what exactly is happening (although close examination of your histogram reveals a lot of pixels where they shouldn't be) . It's best to use a histogram with a column for every value increment. I estimate that around 80%-90% of the pixels fall in between the proper bit depth increments -- the problem is too big to be "ringing artifacts." There is a significant problem... some variable(s) that is uncontrolled, and the images do not simulate the reduced bit depths. No conclusions can be drawn until the problem is fixed.
  22. From the first linked article: So, the first linked article echoed what I said (except I left out that the print itself is also "subtractive" when projected). Is that except from the article (and what I said) what you mean when you refer to "additive" and "subtractive" color? Also from the first linked article: I'm not so sure about this. I think that this notion could contribute to the film look, but a lot of other things go into that look, such as progressive scan, no rolling shutter, grain actually forming the image, color depth, compressed highlight roll-off (as you mentioned), the brighter tones are less saturated (which I think is mentioned in the second article that you linked), etc. Of all of the elements that give the film "thickness," I would say that color depth, highlight compression, and the lower saturation in the brighter areas would be the most significant. It might be possible to suggest the subtractive nature of a film print merely by separating the the color channels and introducing a touch of subtractive overly on the two appropriate color channels. A plug-in could be made that does this automatically. However, I don't know if such effort will make a substantial difference. Thank you for posting the images without added grain/noise/dithering. You only had to post the 8-bit image and the "4.5-bit" image. Unfortunately, most of the pixel values of the "4.5-bit" image still fall in between the 22.6 value increments prescribed by "4.5-bits." So, something is wrong somewhere in your imaging pipeline. Your NLE's histogram is a single trace, rather than 255 separate columns. Is there a histogram that shows those 255 columns instead of a single trace? It's important, because your NLE histograms are showing 22 spikes with a substantial base that is difficult to discern with that single trace. Something might be going wrong during the "rounding" or at the "timeline" phase.
  23. I am not sure what you mean. Are you referring to the concept color emulsion layers subtracting from each other during the printing stage while a digital monitor "adds" adjacent pixels? Keep in mind that there is nothing inherently "subtractive" with "subtractive colors." Likewise, there is nothing inherently "additive" with "additive colors." Please explain what you mean. Yes, but the histograms are not drawing the expected lines for the "4.5-bit" image nor for the "5-bit" image. Those images are full 8-bit images. On the other hand, the "2.5-bit" shows the histogram lines as expected. Did you do something different when making the "2.5-bit" image? If the culprit is compression, then why is the "2.5-bit" image showing the histogram lines as expected, while the "4.5-bit" and "5-bit" images do not show the histogram lines? Please just post the 8-bit image and the "4.5-bit" image without the noise/grain/dithering. Thanks!
  24. If you are referring to "additive" and "subtractive" colors in the typical imaging sense, I don't think that it applies here. There are many different types of dithering. "Noise" dithering (or "random" dithering) is probably the worst type. One would think that a grain overlay that yields dithering would be random, but I am not sure that is what your grain filter is actually doing. Regardless, the introducing the variable of grain/dithering is unnecessary for the comparison, and, likely, it is what skewed the results. Small film formats have a lot of resolution with normal stocks and normal processing. If you reduce the resolution, you reduce the color depth, so that is probably not wise to do. Too bad there's no mark-up/mark-down for <code> on this web forum. The noise/grain/dithering that was introduced is likely what caused the problem -- not the rounding code. Also, I think that the images went through a YUV 4:2:0 pipeline at least once. I posted the histograms and waveforms that clearly show that the "4.5-bit" image is mostly an 8-bit image, but you can see for yourself. Just take your "4.5-bit" image an put it in your NLE and look at the histogram. Notice that there are spikes with bases that merge, instead of just vertical lines. That means that a vast majority of the image's pixels fall in between the 22 "rounded 4.5-bit" increments. Yes. The histogram should show equally spaced vertical lines that represent the increments of the lower bit depth (2.5-bits) contained within a larger bit dept (8-bits). The vertical lines in the waveforms merely show the locations where each scan line trace goes abruptly up and down to delineate a pool of a single color. More gradual and more varied scan line slopes appear with images of a higher bit depth that do not contain large pools of a single color. I checked the histogram of "2.5-bit" image without the added noise/grain/dithering, and it shows the vertical histogram lines as expected. So, the grain/dithering is the likely culprit. An unnecessary element (noise/grain/dithering) was added to the "4.5-bit" image that made it a dirty 8-bit image, so we can't really conclude anything from the comparison. Post the "4.5-bit" image without grain/dithering, and we might get a good indication of how "4.5-bits" actually appears. Using extremes to compare dramatically different outcomes is a good testing method, but you have to control your variables and not introduce any elements that skew the results. Please post the "4-5-bit" image without any added artificial elements. Thanks!
  25. I think that the "thickness" comes primarily from emulsion's color depth and partially from the highlight compression that you mentioned in another thread, from the forgiving latitude of negative film and from film's texture (grain). Keep in mind that overlaying "grain" screen on a digital image is not the same as the grain that is integral to forming an image on film emulsion. Grain actually provides the detail and contrast and much of the color depth of an film image. Home movies shot on Super8 film often have "thick" looking images, if they haven't faded. You didn't create a 5-bit image nor a "4.5-bit" image, nor did you keep all of the shades within 22.6 shade increments ("4.5-bits") of the 255 increments in the final 8-bit image. Here are scopes of both the "4.5-bit" image and the 8-bit image: If you had actually mapped the 22.6 tones-per-channel from a "4.5-bit" image into 26.5 of the 255 tones-per-channel 8-bit image, then all of the image's pixels would appear inside 22 vertical lines on the RGB histograms, (with 223 of the histogram lines showing zero pixels). So, even though the histogram of the "4.5-bit" image shows spikes (compared to that of the 8-bit image), the vast majority of the "4.5-bit" image's pixels fall in between the 22.6 tones that would be inherent in an actual "4.5-bit" image. To do this comparison properly, one should probably shoot an actual "4.5-bit" image, process it in a "4.5-bit" pipeline and display it on a "4.5-bit" monitor. By the way, there is an perceptible difference between the 8-bit image and the "4.5-bit" image.
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