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tupp

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Posts posted by tupp

  1. We've had heated discussions in this forum on the DOF equivalency principle and on the difference in the looks of different size formats.

     

    I am on the side that there is definitely a difference in the general look of different size formats.  I also maintain that the DOF equivalency principle does not account for the rate that the focus "falls off" outside of the mathematical DOF range and that this DOF falloff rate differs between different formats.

     

    Keep in mind, that the assertions above apply not to the size of a sensor nor emulsion, but to the optics made for a particular size of sensor/emulsion.

     

    If one compares the images from a 16mm camera to those from, say, an 8"x10" camera, the difference in look and DOF falloff is striking.  Here is footage from a recent 8"x10" camera:

     

  2. 2 hours ago, JuiH said:

    hi, would ETTR still be suitable for 8-bit 4:2:2 from a 5D MArk iv or an EOS R? i have C.Log on both of them. i much prefer the 10-bit 4:2:2 of my Sony FS-5 however i find it harder to achieve pleasant skin tones with the Sony than with either of the Canons.

    Even though the format you mention may be uncompressed, the fact that it is 8-bit might cause banding artifacts to appear when you adjust the levels back down in post.  Be careful and/or run tests in advance.

     

    In your NLE, you might find filters that have sliders and color wheels that will allow you to quickly change the Sony skin tones to your liking.

  3. ETTR is suitable for raw and uncompressed formats.

     

    Just be careful going by a histogram alone.  If you have zebras, set them in the range of 95%-100%, and use them to determine your upper limit and to choose which parts of the image may or may not blow-out.  Waveform is also good for finding the upper limit.

  4. 30 minutes ago, cam1982 said:

    Sure not, the guy didn't create Oakley either.

    Well, he certainly didn't invent tacky sunglasses and ugly shirts.

     

     

    31 minutes ago, cam1982 said:

    Just hype.

    Promo-wear has built-in hype, just because it is part of the fashion industry.  On the other hand, the sunglasses and shirts probably didn't get as much hype as the RED One, which was vaporware for about 3 years.

     

     

    32 minutes ago, cam1982 said:

    A perfect hoax.

    The RED founder and "hoax" mentioned in the same post?  Oh, the irony...

     

     

    34 minutes ago, cam1982 said:

    Maybe we too and didn't notice yet.

    Some guy made a video about RED's special drives.  I think he noticed something.

  5. 1 hour ago, nathlas said:

    Has anyone in here bought any Dalsa camera ?  ?

    Has anyone here bought a Panavision DXL?  ?

     

    Whether or not someone on this site bought something has no reflection on the innovation nor quality of the item in question.

     

     

    1 hour ago, nathlas said:

     In case you don't remember Dalsa's rental price was 3k$/day !!!  

    I don't think that I ever actually knew what the rental prices were on any one of the different Dalsa 4K raw cameras.

     

    Nevertheless, Dalsa was offering 4K raw long before it was even a glint in Jannard's eye.

     

    Keep in mind that the first ones to break ground usually incur the most development cost and sink the most resources into a type of product.  So, initially, a new type of product is usually very expensive.  Often, someone with deep pockets sees the development, and swoops into a market to take advantage of it (and gets all the credit).

     

     

    1 hour ago, nathlas said:

    How it compares with 15k$ to own RedOne ?

    How does that $15K, very late-to-market, buggy RED One compare to a $1,500 Pocket4K?

     

    Do you see how that works?

     

     

    1 hour ago, nathlas said:

    Jannard's revolution made those camera affordable to all of us .

    Jannard just rode a wave.  Raw video and higher resolutions were inevitable in cinema cameras, as was raw compression.  He didn't invent really anything.

  6. 4 hours ago, nathlas said:

    They propably do not remember well around 2007 where Red  launched RedOne at a cost(15k$) of a Sony Cinealta's screw ? (Sony F23 and F35 cost was over 100k$) and deliver for first time RAW files

    RED was not the first to offer a cinema camera that shot 4K raw -- that distinction goes to Dalsa.  Dalsa introduced their 4K raw camera at the 2003 NAB.

     

    At any rate, 4K raw and compressed raw were inevitable and obvious in the cinema world.  At the Dalsa 2003 launch, raw files and the megapixels war had already been around for years in the still photo world.  So, it doesn't take a genius to simply apply such notions to moving pictures.

     

    In regards to RED's wavelet compression, it had already been established in JPEG2000.  So, it doesn't take a huge mental leap to merely apply the same compression method to another video format.

     

  7. 3 hours ago, Shell64 said:

    There is something about the camera being locked down and moving compared to a gimbal where the camera is “floating and moving.”

    Up until about eight years ago, we said the same thing about the difference in the solidity of the look between a dolly and a Steadicam.

  8. 2 hours ago, sanveer said:

    Also, curiously it has an EF mount (?). I think all this is true, Panasonic has truly something insane in the offing.

    Agreed.  If Panasonic uses an EF-mount once again (in spite of the fact that they already utilize the shallow and more versatile L-mount), that is truly something insane!

  9. You are making a large format DOF adapter and using anamorphic optics?

     

    Our own @Gonzalo Ezcurra made the largest format DOF adapters that I have seen.  I don't think that he ever tried anamorphic optics on them, but you should probably be aware of them, nonetheless.

     

    He made a 20"x20" version, called the "E-Cyclops."  Then, he made a smaller, 14"x14" version, called "MiniCyclops."

     

    Here is construction of the E-Cyclops.

     

    Here are some of the results, evidently from the MiniCyclops.  Unfortunately, he took down all of his amazing videos shot with these devices.

     

    He also made a motorized focus mechanism and a motorized stand for the cameras.

  10. 1 hour ago, Braydon said:

    holy crap! I just cruised over to the ML forums on the Pink Dots and I was not ready for the amount of info I got into. Multiple programs and pixel mapping and coding?!!

    Again, the pink dots in the highlights of your video appear to be very different from the pink focus pixels that are discussed (and mapped out) on the ML forum.

     

    Upon a closer look, I see that focus pixels sometime appear in your video in the same frames as the pink highlight "fixed pattern" dots.

     

    Here is what pink focus pixel dots look like:

    22229569838_cfcf5c981a_b.jpg

    Notice the distinctive, orderly pattern of the pink focus pixels.  These faint orderly dots are easy to map out.

     

    The pink highlight dots in your video seem to be some other problem, likely related to the pink highlights phenomenon (completely different from the pink focus pixel phenomenon) and possibly also related to fixed pattern noise.

     

    Again, you additionally  have a "black hole Sun" problem.

     

    I think that the free, open source MLV App will solve most of your problems, but I am not familiar with it.

  11. 53 minutes ago, Braydon said:

    HE ONLY ISSUE ON THIS FIRST RUN WAS THOSE DAMNED PINK DOTS!!! I know they have been discussed on other threads, so it's time to dive deep into that issue,

    Those pink dots don't look like the typical focus pixel dots.  The problems is something else.  It appears that you are also experiencing black (pink?) hole Sun effect.

     

    I seem to recall reading in the Magiclantern EOSM thread and watching one or two recent @ZEEK videos on how to remedy pink highlights and black hole Sun with EOSM raw.  As I recall, one just lowers the white level in MLV App to eliminate the pink highlights.

     

    Perhaps, @ZEEK and/or @Alpicat will chime in with suggestions.

     

     

    52 minutes ago, Braydon said:

    Here is a little vid I put together quickly from the shots I took in the Santa Barbara Harbor this morning.

    Nice!  Thanks for sharing!

     

     

  12. 2 hours ago, androidlad said:

    You are talking about encoding bitdepth, 8bit H.264, 10bit ProRes etc.

    I am talking about everything that involves converting an analog signal to a digital signal, including the signal going into a camera sensor's ADC and the signal coming out of that ADC.

     

    By the way, there are zillions of machine vision camera that offer selectable bit depths.  There is no encoding nor compression nor codec.  The bit depth changes, but the dynamic range doesn't change.

     

     

    2 hours ago, androidlad said:

    Sensor ADC readout precision dictates the upper limit of the total DR the sensor can output.

    No.  It doesn't.

     

    Barring any artificial signal processing, the max limit of dynamic range is dictated by the analog stage of the sensor.  Dynamic range is essentially (originally) a property of analog signals notated in decibels, regarding the maximum signal amplitude relative to its noise level.

     

    An ADC merely maps some number of digital increments to an analog signal's amplitude range (not to the signal's dynamic range).  Regardless of how many digital increments the ADC maps, the relationship between max amplitude and noise level remains the same.

     

     

    3 hours ago, androidlad said:

    Do you know what ADC is? It's absolutely linear.

    Analog to Digital Converter.

     

    Most ADCs for camera sensors are linear.   Certainly, other ADCs exist that don't make a linear conversion.

     

     

    3 hours ago, androidlad said:

    12bit ADC theoretically offers 12 stops maximum DR, and BMPC6K does 11.8 in lab test.

    10bit ADC = max 10 stops, as demonstrated by the noisy shadows in ZCAM E2 4K 120p footage.

    Alexa uses dual 14bit ADCs, it's one of the reasons why it's capable of 14 stops of DR (then stored logarithmically in 10bit ProRes)

    Most stills cameras use 14bit ADC for stills and that's why A7 III achieves 13.9 stops DR in stills mode.

    First of all, a lot of folks who have tested Alexas would disagree with you and and say that it's dynamic range (in stops) is greater than it's bit depth -- 15+ stops of DR.

     

    However, the manufacturer Blackmagic's sensor could integrate an 8-bit ADC with the same analog stage of their 12-bit sensor and also make another sensor with a 16-bit ADC to go with the same analog stage, and the dynamic range would not differ one iota between the 8-bit version, the 12-bit version and the 16-bit version.

     

    The reason why the dynamic range (in stops) in CMOS sensors often approximates the bit depth of the ADC is because it is usually the most optimal/efficient balance between bandwidth and color depth.  Mapping 16-bits to a sensor with 12 stops of dynamic range probably wouldn't improve the look much, but it would significantly increase bandwidth.   Similarly, mapping only 8-bits to a sensor with 12 stops of dynamic range would severely limit the potential color depth and might make the images susceptible to banding.

     

    There are camera sensors that have outboard ADCs (not built into the sensor), and, changing the bit depth of the ADC has no effect on the DR.

     

  13. 1 hour ago, androidlad said:

    Ha, I've explained many times, current commercial CMOS sensors behave linearly, and linear 12bit = 12EV = 12 stops of DR.

    Ha, ha!  Likewise, I've explained many times that dynamic range and bit depth are two different and independent properties.  I have also given practical, existing examples of cameras that offer variable bit depth while maintaining the same dynamic range -- the bit depth varies independently from the dynamic range.

     

    In addition, there exist cameras in which one can change the effective dynamic range while maintaining the same bit depth.

     

    It is a misguided notion that CMOS sensors (or any other types of digital sensors) have some sort of absolute linear relationship between dynamic range and bit depth.  12-bit ≠12 EV   and 12-bit ≠ 12 stops DR.

     

     

    1 hour ago, androidlad said:

    Yes you can store unlimited DR in 8bit, that's called logarithmic encoding.

    The mapping of bit depth increments is independent from the bit depth and also independent from the DR.  You can map 8-bit logarithmically, linearly, rec-whatever or any other way -- regardless of the DR.

     

     

    41 minutes ago, Video Hummus said:

    So glad @androidlad posts on this forum.

    Me too!

  14. 1 hour ago, Eugenia said:

    I own 4 Canons

    Is one of those Canon cameras an HV20?

     

     

    1 hour ago, Eugenia said:

    I pulled the trigger just last week and bought a Sony A6400 with its kit lens, and an EF/S adapter. The A6400 has its own crippled sensor with (surprisingly high) rolling shutter.

    [snip]

    At the end, it's Fuji that it's going to win me over though, I know it in my gut. As long as they have an updated X-T3 with ibis, I'm there. I'll get their f/2.8 kit lens zoom, and the Fringer EF/S adapter, and I'll be golden for many years to come, I reckon.

    Why didn't you just go with the X-T3?

     

    Welcome to the forum!

     

  15. 59 minutes ago, User said:

    ... and I often see post go up on crew websites from producers requesting DPs that must have a Red to get the gig while saying nothing of how they can light etc.

    Yep.  That's been going on for years -- even before Red existed.  One can safely assume that the above-the-line folks are clueless and cheap, when, at the outset, they stipulate that a DP must own a certain brand of camera.

     

    One exception to this assumption is that they might be trying to match previous footage.  However, in that case, they are just cheap and one wonders what happened to the original DP.

     

     

    1 hour ago, User said:

    Anyway, this up today and worth a read for the perspective:

    Jenkin: I made a 45-minute film a few years ago called Bronco’s House, which was processed in a developer made of instant coffee, vitamin C powder, washing soda crystals and a little pinch of potassium bromide to keep the grain down. You can make developers from anything, really, as long as you’ve got an alkali base and an active acidic ingredient. I quite like that side of things. I like experimenting with how you can create pictures.

    https://filmmakermagazine.com/108148-with-digital-you-have-to-spend-a-lot-of-money-before-it-becomes-free-mark-jenkin-on-his-hand-processed-16mm-bait/?fbclid=IwAR2tzdi_7xggt6PKoF1XJZDiWH1VYQoeaut0w9L97JwhtA4f-qLGlTgv0ko#.XWqjp5NKjOR

    The trailer (thanks, @PannySVHS!) is reminiscent of the inexpensively made, slipshod "Now" films of the mid/late 1960s.  Very cool!

     

    Not sure why he didn't just an use an off-the-shelf developer, stop bath and fixer.

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