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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Help!! Serious artifacting!

full debayer outputting to dnxhd produced the most artifacting....no compression and proreshq was much better...and to a certain extent useable..
actually, i see the artifacting occuring as i move the curve in RedAlert already
 
Artifacts and monitor gamma?

Artifacts and monitor gamma?

flowerchildprojekts said:
actually, i see the artifacting occuring as i move the curve in RedAlert already
Click to expand...

If you can reshoot try setting everything 5500K, use 80 series filters and CTB to have 5500K light going into the camera, and use more fill light, shoot at EI320. If that does not look good on a CCed TIF 16bit (48bpp) REDlog then you might need to shoot with another camera and compare the results to see if they are the same in both cameras?

Your monitor gamma settings or your image viewer gamma settings can make the artifacts look brighter than they would on another computer or TV. You can try another computer and monitor to see if the gamma is off standard 2.22 for HD, you can load a gamma reference image that only has horazontal lines, the ones with checker board, dots, or vertical lines are not accurate.

See also the post I made below with the testx1.jpg inverse image to look for underexposure in the image, like the shadows in the folds of the jacket.
 
www.DANCAD3D.com said:
If you can reshoot try setting everything 5500K, use 80 series filters and CTB to have 5500K light going into the camera, and use more fill light, shoot at EI320. If that does not look good on a CCed TIF 16bit (48bpp) REDlog then you might need to shoot with another camera and compare the results to see if they are the same in both cameras?

Your monitor gamma settings or your image viewer gamma settings can make the artifacts look brighter than they would on another computer or TV. You can try another computer and monitor to see if the gamma is off standard 2.22 for HD, you can load a gamma reference image that only has horazontal lines, the ones with checker board, dots, or vertical lines are not accurate.
Click to expand...

thanks dan, but reshooting is not an option :(
anyways, the artifacting is not as obvious on my macbook pro...
 
Underexposed?

Underexposed?

flowerchildprojekts said:
thanks dan, but reshooting is not an option :(
anyways, the artifacting is not as obvious on my macbook pro...
Click to expand...

The bast way to check for underexposure or bad grading/processing is to invert the image to negative.

I first noticed this doing tests with my film recorder program, DANCINEL.EXE (tm). the RED ONE (tm) footage shows heavy artifacts in the shadow areas, that inverted on the monitor for printing to color positive stock 2384 become easer to see because of the monotor gamma adjustments for printing.

To me it looks like the footage is underexposed or you did something wrong in making the TIF file. If I had the R3D I could confirm underexposure.

RED CODE does not seem to like the bottom 4 bits, so the range of the sensor should be thought of a 8 bits rather than 12bits for exposure. You need like 2 stops more fill light, you can always make it darker in post, but you cannot put data back that was filtered out with the compression.

Look in the shadows of the folds in his jacket, nothing seems to be there in this example. Try other options for making a REDlog TIF that do less to the original data and see if you can see any shadow detail in an inverse image that is gamma adjusted and sharpened.
 
www.DANCAD3D.com said:
The bast way to check for underexposure or bad grading/processing is to invert the image to negative.

I first noticed this doing tests with my film recorder program, DANCINEL.EXE (tm). the RED ONE (tm) footage shows heavy artifacts in the shadow areas, that inverted on the monitor for printing to color positive stock 2384 become easer to see because of the monotor gamma adjustments for printing.

To me it looks like the footage is underexposed or you did something wrong in making the TIF file. If I had the R3D I could confirm underexposure.

RED CODE does not seem to like the bottom 4 bits, so the range of the sensor should be thought of a 8 bits rather than 12bits for exposure. You need like 2 stops more fill light, you can always make it darker in post, but you cannot put data back that was filtered out with the compression.

Look in the shadows of the folds in his jacket, nothing seems to be there in this example. Try other options for making a REDlog TIF that do less to the original data and see if you can see any shadow detail in an inverse image that is gamma adjusted and sharpened.
Click to expand...

i shot this at 320 asa....but output the tif as 200 asa as per gunleik's request....could it be the reason it looks underexposed?
 
OK.

There is too little contrast between the subject and bacground, the good thing is that the shirt isn't overexposed and blown, like it was on initial posts. To me the hair looks quite good... Thus, you have a development problem...

You seem to be slightly off focus, but than can be good if you're going to SD... :) It is an issue between the jacket and the background, though...

the pattern-noise you see in the background is right - sorta, but there is enough contrast to get rid of it. The halo around the head makes some problems. You can minimize the noise further by lowering the exposure even more and possibly start with an even higher kelvin. Then you will have to compensate the color in the matrix. and the dynamics with brightness/contrast.

Your real problem is that you try to correct in RA. A better option would be to develop to DPXs more or less like the file you gave me and CC in a proper grading suite, but I guess that's not an option.

If you're looking @ a computerscreen, some of the noise issues are multiplied...

But to me, what you sent me now looks like a fixable startingpoint...
 
thanks Gunleik, glad to know it's fixable...i'm gonna try to get this on a HDTV Lcd or plasma....
 
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