Archive for February, 2009

New Alacrity Media in ASC Magazine January 2009 issue!


For those of you who subscribe to American Cinematographer:

Look for Alacrity Media in the January 2009 issue on pp. 84-85. Our Road Grader mobile editing and color grading suite was featured as part of the New Products & Services segment. It’s nice to see hard work and innovation pay off! Thanks for your support.

-Alacrity Media Production and the 4K Ninjas

for more info, or to subscribe to ASC Magazine, visit

New CTB (color temperature blue) filtering for the RedOne Camera


CTB (color temperature blue) filtering for the RedOne camera:

I love the idea of a filter purpose built to raise the color temperature/white point with as little light loss as possible. Several people have contended, some with a fair amount of test results to back up their assertions, that raising the CT makes for cleaner keys and better noise characteristics. Other have argued that when light levels are low it is better to keep every photon you can so that the red and green channels can provide grist to extrapolate the blue information.

From what I’ve seen there is an issue in terms of the “subjective noise awareness” factor of the viewer when the blue channel is starved and base level sensor patterning reveals. For this reason I advocate the “careful” use of blue filtering, especially in available light situations where the native CT may be less than 3000 Kelvin.

I would not give away a stop or more just to nail 5000K but I would, for example, give away 1/3 stop to get to 4000K. In a perfect world I would carry 3 filters of differing strengths designed specifically to compensate for the lack of blue sensitivity inherent in the current crop of CMOS sensors.

It is my belief that Graeme’s algorithms perform best when the inequality of the color channels is more moderate. This advice is based on tweaking a lot of underexposed footy in Scratch in full res, full debayer with an eCinema reference monitor. YMMV.

I am a big fan of Schneider filters and am stoked to see them jump in with CTB options. 80 series filters are designed to allow the use of tungsten balanced film stocks in daylight shooting. I contend this particular MIRED shift is based upon assumptions that are overkill for the RedOne’s Mysterium CMOS sensor and results in more light loss than necessary. I consider it silicon chip color response compensation and prefer a filter that does exactly that.

Thanks to David Mullen for helping me understand this issue.

Blair S. Paulsen
4K Ninja
San Diego

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New When is a meter…


While metering the RAW is a good reference point, in my experience there is more to the story.

IMHO the best way to get exposures that match your intent is to run a simple test. This will not be a definitive technical measurement but it will help you to learn the relationships between the various tools like false color and the histograms. Get a feel for what the monitor tap puts out versus a processed RAW image, etc.

1) Medium shot of a human subject, a test chart or gray card, the background should be a mixture of colors, have some hard light and a softer source.

2) Set the camera ASA/ISO to 320 (yes Viginia, it is a bit slower than that) and set a fat stop like F4 on the lens, remember this is only a test - seeing the effects of over and/or under exposure is good information.

3) Mess around with every exposure tool there is: light meter (incident and spot reading galore), histograms, RGB stoplight, false color, etc and repeat any on camera readings in RedSpace, Rec. 709 and RAW. (Disclaimer: the version of RAW the camera is showing you may be gamma encoded and has been reported as variable depending on which firmware build you are running. For specific information on this matter please ask Stuart English as he knows the details a thousand times better than I do.)

4) Roll short clips at F2.8, 4 and 5.6. Open the clips in RedAlert, RedCine or Scratch. Look at the histogram! Play with all the controls and see the results with your own eyes. Make some 4K TIFF stills and open them in Photoshop if that is a familiar working environment for you.

After you have taken the best exposed clip and adjusted it to suit your taste compare the processed image on your monitor to the RedSpace monitor tap live off of the camera. Using the same stop as the best exposed clip reference image, run through the various exposure measurement aids and judge their accuracy for yourself.

My personal working style has evolved to using false color in RedSpace as my primary exposure reference. While I don’t care to dispute those who claim that the only reliable information is linear light RAW I work in the real world where RedSpace output is the most client friendly choice. By training my eye to know what RedSpace false color readings mean in reference to what I will have to work with when grading the RedCode RAW data in Scratch (or RedAlert) I get excellent results. YMMV.

Blair S. Paulsen
4K Ninja, RedOne #19

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