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Bob Speziale

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Everything posted by Bob Speziale

  1. Thank you David. So the magic words for google and youtube are pixel binning for video and line skipping for video. Much appreciated. The article and video answer my questions. Your original answer and some of the answers in the thread were above my knowledge of the terms to sink in. But I have it now.
  2. Problem with google is it will bring up a million hits related to dslr video specs, nothing on how the video actually records, other than mentioning the crop factor (eg. full frame video on some models, or the video crop factor). That is, they will describe the output, all aimed at potential buyers and users, but nothing on how the output gets produced. This post is the only time I have ever seen the actual mechanics of creating a 2MP video frame discussed anywhere. Maybe it's some sort of trade secret.
  3. Thank you David. Are there any published articles or video on the process? I was surprised that this was one subject where Google failed me completely.
  4. My original question was what is that algorithm? DSLRs have been creating HD video streams for about a decade but I haven't seen any articles on how they do it. Do they just use 2MP of the sensor and tuen off the others, or do they use 2MP of the sensor and rotate to another 2MP for the next frame, or do they use the whole sensor and downsize the image to 2MP?
  5. The BMPCC shoots 12 bit raw dng files which contain about 10x the data that downsized dslr video frames do. To me it just looks better. Here's a single frame from a video I shot at iso-1600 in daylight coming through blinds at f3.5. Here's a single frame (downsized to post here) and a crop of that frame. Colors and skin tones just look better to me. I was thinking this over last night and realized dslr's usually offer a choice of image size, high, medium and low quality images that will reduce the file size, eg. for emailing. It seems likely that this may be the same process used to ceate the 2MP digital video frames, whatever that process is.
  6. I was just curious because I couldn't find any easy answers anywhere. I know my 50MP 645Z and my 2MP BMPCC both shoot 1080P video. The BMPCC image seems the best.
  7. So it's just the 2MP in the center of the sensor that is used, with all the other pixels turned off? But isn't the lens projecting the image over the whole sensor (or most of it if the video is cropped a bit to 16x9)? But if most of the sensor is used, is the image downsized by the camera to 2MP before the frame is captured?
  8. I don't know how you can say that. Even with a screen shot of the two images on my 2K monitor (film on left) reduced in size to post here, you can see the digital image has more blues and the film image has less. If it's not so apparent in skin tones it's obvious on the window frames.
  9. For those of you with technical knowledge, maybe you can answer this question. How does a DSLR with a 16 or 20 or 50MP sensor capture 2MP digital video frames? Are most of the pixels turned off? Are the 2MP images captured by the same pixels on every frame, or after each frame is captured are another 2MP on the sensor used? Or is the whole sensor used used and the frames then downsized? Or something else? On my BMPCC original camera, it has a 2MP sensor, so the same pixels get used for every frame. But how about on a 16MP , 21Mp or even 50MP DSLR?
  10. Looking at Yedlin's demo I did see a difference. The left side seemed just a little more saturated and colorful to me than the right, especially in the skin tones. At the end of the demo it said the left side was the 35mm film. This isn't a surprise. Having shot digital and film still pics, I've found no way to 100% match colors of the two, even taken side by side at the same time. They are different, but only noticeable if viewed side by side. Otherwise, once the mind is drawn into the content, it's not noticeable. Back in 1964, most of us got to love the Beatles listening to them on transistor radios with one inch speakers. Art is experienced more in the mind than in the eyes or the ears.
  11. The grade looks OK to me. The noise is likely from the low light.
  12. Very well done. Looks professional. Just curious, what cameras and lenses are you using? Great cinematography.
  13. I used my video editing software to capture and record footage from my mini dv Sony camera to my fire wire equipped laptop. The output was a AVI file at 720x480 resolution. Data rate was 29,000 mbps.
  14. Thanks for posting this response to my question Tyler. I can see similarities to my own start as a computer hobbyist, self taught, doing computerized accounting and database installations for small businesses as a sideline for about 10 years while working as an audit manager to pay the bills, and getting that big lucky break when a person hired from IBM to head up a computerized drafting project quit and I was offered the shot, which led to a very satisfying 20 year career as a sys admin and dba until I retired. I think your story and Phil Connolly's is quite instructive in the amount of time and work and flexibility it takes to become established in a chosen field. It's probably not something that is taught in school, but really should be. Getting to make a living in a field we love takes a lot of hustle, desire, talent, learning, experience, patience, resilience, and luck. Luck may open the door, but you must be willing to jump in and work hard to make that luck pay off.
  15. Tyler, it would be instructive to know how soon after graduation you got your first job in your field and what was it, and how did you get it. Ditto for your second job in your field. How long before you actually could make a living in your field? It seems everyone's biggest obstacle after graduation in many fields, starting off with no money or connections, is getting their foot in the door. You need experience to get hired, you need to get hired to get experience. In my own field of computer specialist it took me 20 years to get where I wanted to be, well paid, appreciated, with enough expertise to be left alone to do the work as I thought best.
  16. Perhaps the problem with higher education is that they ought to be more like trade schools. If you go to welding school, you come out a welder and start as an apprentice. If you graduate from dental school you go to work and start filling cavities. If you go to film school, it seems you generally don't come out a cinematographer or get hired as an apprentice cameraman. So the question would be why not.
  17. Mamiya 645 Secor C lenses are a little soft. It's a unique look you may or may not like. Buy an adapter and try it. Fotodiox lets you return adapters within 30 days if it doesn't work out.
  18. I'm guessing something similar could be done in digital with a very slow shutter speed, changing the exposure and contrast and adding colored ambient light and blur in post.
  19. Excellent photography. I actually did screenshots on YT at 2K and 4K and there was barely a noticeable difference. Much less than I would have expected. I also did some experiments on my own shooting the same scene with the same settings in 2K and 4K and comparing screen shots. It's making me reconsider my views on 4K vs 2K. I wonder if studio lighting or bright sunlight is needed to see a noticeable difference.
  20. Work is a place where they pay you what you are worth, you are selling your skills. School is a place where you pay them to teach you, where you learn how to learn, but probably don't learn the skills you will need on the job. The diploma may get you an interview, but how you do on the job is mostly a function of how well you can manage the relationships with your bosses and co-workers, how eager and capable you are to learn and get up to speed quickly, and your overall attitude and enthusiasm. You can't count on getting many lucky breaks in life, but when they come, take full advantage of them and do whatever is required to make them work. If you can't get an MFA now, concentrate on getting that first job, on getting your foot in the door. You can always find out what is being studied in the MFA program, and study on your own. Doing that while you work will be more meaningful than doing it in a classroom.
  21. Thanks for the info Frank. Most of my tapes are music tapes and have been replaced with CDs. I will dump them in the garbage one of these days, but if I see one I want to save, I'll try the baking method before recording it digitally.
  22. If the stage lighting changes then your iso or shutter speed or aperture has to change as well. Auto iso can be tricky because it may adjust to illuminate the darkest part of the frame, which can blow out other parts. While dark frames can be lightened in post, blown out areas can't be recovered. And if the area being recovered is too dark, it may not look that good either. With two cameras you could set one for the dimmest lighting and the other for the brightest. I don't know how else you could handle it.
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