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3D 3K 12-bit RAW camera project
  • 133 Replies sorted by
  • gangstak2gangstak2

    Here's a dropbox link for a zip that includes a .raw12 file and a .DNG created from that file in DANcinec: https://www.dropbox.com/s/m50y2mxsrcn818x/Stippling%20Sample.zip

  • zcreamzcream

    Looks like the demosaic algorithm. http://www.pages.drexel.edu/~par24/rawhistogram/40D_Demosaicing/40D_DemosaicingArtifacts.html The artifacts are similar to those with AHD and PPG. They go away when 4 color demosaicing is applied. Try dcrawms -q 4 -f -v -a The speckles left over seem to be noise and they would be reduced by dark frame methods. The explanation is interesting too..

  • zcreamzcream

    Can you also try to set Gain to 0db and capture dng ? Turns out that gain is only modifying the digital gain which will definitely introduce artifacts.

    > The A/D converter provides a PxGA gain stage (white balance/preamp) and VGA gain stage. The main VGA gain stage is available to the user, and is variable up to 24 dB in steps of 0.046 dB.

  • gangstak2gangstak2

    I tried using 0db gain a couple days ago with a bright outdoor scene. Still got the same stippling artifacts.

  • zcreamzcream

    Did you try the dcrawms fix I mentioned ?

  • zcreamzcream

    Can you also try gamma = 1 and sharpness=100 ? These settings at gain=0db. Brightness should be at 0 - though this only affects the black level. This looks more like a digital artifact than a XYZ RGB mapping if its not visible at 0db.

  • gangstak2gangstak2

    I tried your settings using dcrawms. The resulting images never matched the quality of FlyCap's YUV422 output. They were fairly splotchy and some stippling remained.

    However, today I discovered something very promising. Using your version of FlyCap, I selected RAW16 instead of RAW12 and chose DNG export. When I opened up the resulting DNG in Photoshop, the top 75% was garbled, but the bottom 25% looked perfect - very similar to the YUV422, no stippling at all. I've attached a graphic that compares YUV422 exported to TIFF, RAW12 exported to DNG, and RAW16 exported to DNG.

    Do you think my stippling issue could be related to bit depth interpretation?

    YUV422 RAW12 RAW16 Comparison.jpg
    1494 x 1128 - 266K
  • zcreamzcream

    Try this version - https://dl.dropboxusercontent.com/u/9906333/FlyCap2.exe

  • gangstak2gangstak2

    Much better!

    With RAW12 exporting to DNG, I get no more stippling. And it's significantly sharper than YUV422.

    The only problem that remains is the interpretation of exposure and white balance. Photoshop is bringing in the DNGs significantly overexposed and with a skewed white balance - very, very purple. When I adjust the exposure and white balance to compensate, I end up with discolored highlights. Could this be a metadata issue?

  • zcreamzcream

    Or XYZ to RGB mappings. If you have a color chart, can you shoot it ? Bring it into PS, and redo the DNG profile using the Adobe Profile Editor. https://www.adobe.com/support/downloads/detail.jsp?ftpID=5494 Does that help ?

  • zcreamzcream

    Updated version now saves Black Level and frame rate (currently hard coded to 25fps) in Cinema DNG tag. This will provide correct brightness viewing in the RAW viewer. The preview is still off within the FlyCap2 - thats to do with the way that PGR is setting gamma and brightness/exposure when mapping 12-bit to 8-bit for display.

  • gangstak2gangstak2

    I used DNG Profile Editor. I had to import an underexposed color chart image to compensate for the default overexposure, otherwise it gave me an error message about blown greys. The custom color recipe might be helping. With images I shot today (daytime indoor shot with a mix of tungsten and daylight), the highlights look fine. With images I shot two days ago (nighttime indoor shot with all tungsten), the highlights are still discolored, even with the new color recipe.

    Is your newest version of FlyCap up on dropbox yet?

  • zcreamzcream

    Yup - same link. I overwrite when I update.

  • zcreamzcream

    Just in case some clever person Is reading this. I also cannot figure out how the embedded metadata in interpreted.

    My values are

    Brightness 0%

    Exposure 0.415 eV

    Shutter 39.974 ms

    Gain 12.007

    WB - Red 550 Blue 550

    The values in the metadata are

    Brightness C2000000

    Shutter C20008CC

    Gain C20005FE

    Exposure C2000100

    WB 82226226

  • zcreamzcream

    Updated with Cinema DNG tags, and white level. Also dng sdk has been integrated. I turned off lossless JPEG mode as its not fast enough, and I can seem artifacts. https://dl.dropboxusercontent.com/u/9906333/FlyCap2.exe See this example https://dl.dropboxusercontent.com/u/9906333/dngs.zip out.dng is generated using dng sdk. Look at the edges of the white chair. Classic JPEG compression artifacts!!

  • gangstak2gangstak2

    When I select DNG as the save format, the program now crashes and I get the "application has stopped working" message (exception code c0000005). The other save formats don't crash the program.

  • zcreamzcream

    Can you select all the embedded fields ? Its trying to read the timecode.

  • zcreamzcream

    This particular is not suited for 3d. Its unfortunate that I had to wait a couple of months before realizing this. When one of the cameras is coupled with ext trigger - via the Hirose GPIO pins, the available frame rate drops drastically. I cannot get more than 16fps on any HD size video mode. Such a shame!

    I will be checking with Point Grey to see if any other cameras do manage to go to a higher frame rate.

  • gangstak2gangstak2

    I selected all the embedded fields, but the program still crashes when I try saving to DNG.

  • zcreamzcream

    Try the latest build. It will save the first frame as all white data. So save at least 2 frames if you want check usage.

    The advantage is that the first frame can be used to check cDNG header fields, and the second one for any transform/compression problems.

    If something does not work, let me know if the directory was created and a DNG image was saved.

  • gangstak2gangstak2

    The latest build works. The initial white balance in Photoshop is now closer to what I'm seeing in FlyCap, but the images are still coming in overexposed. I can compensate for this with a negative exposure adjustment, but I'm often left with discolored highlights.

    Screen Shot 2014-03-27 at 12.42.29 AM.jpg
    756 x 481 - 48K
  • zcreamzcream

    Set Gain and WB (red and Blue) to zero. PGR only offers digital gain. And you can achieve all this in post anyway. With Brightness set to 0. Now can you shoot a color chart and generate a DNG profile in the profile editor ?

  • gangstak2gangstak2

    Setting the red and blue white balance to zero results in an extremely green image. It's so green that DNG Profile Editor fails to create a color recipe. Even with a properly exposed image, it gives me the error message, "Unable to check white balance using grey patches." Presumably the software will only stretch the white balance a certain amount.

    When I choose a white balance that looks decent in FlyCap, such as 500/700, DNG Profile editor is successful in creating a color recipe.

    Regarding the gain, I see the merit in avoiding digital gain. But for monitoring purposes, would there be any way to turn up the gain in FlyCap without affecting the DNGs?

  • Vitaliy_KiselevVitaliy_Kiselev

    Interesting 3D camera - http://www.codexdigital.com/products/action-cam

  • zcreamzcream

    :-) Its the price I'd be worried about.

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