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View Full Version : Making REC709 look like RAW with saturation?



Matthew Rogers
04-02-2009, 07:03 PM
So after finding out that both the Histogram and False Color are linked to the color space they are in and not the RAW exposure, I have been thinking about how to monitor better. My first thought was to go to RAW colorspace and then turn up the saturation. However, when in RAW you can't change any settings like Saturation or Exposure. So my thought now is to go into REC709 colorspace and turn down through either Exposure or Curves the gamma to more closely match RAW. That way I get a nice colorful, saturated image, but without underexposing like REC709 and REDSpace can lead to.

So my question now is, how can I accurately test my settings to get it as close to RAW gamma? Is a gray card at 18% the only way?

Matthew

David Mullen ASC
04-02-2009, 09:14 PM
What have monitor chroma saturation levels got to do with exposing accurately?

Larkin Seiple
04-02-2009, 11:58 PM
I have recently shot feature using several different RED camera bodies from one camera house and have experienced problems with exposure and saturation when grading the image on set. REC 709 either comes of as nuclear green with a strong magenta kick or something degraded but ultimately both bodies i have used give me an image that affects my judgment on set with color and exposure. In post i dial everything back to raw and add my contrast and saturation to my taste allowing me freedom but i would prefer to dial it in on set and create the color and exposure variance i prefer there. any ideas? I have been try to find a different color profile given that rec 709 so far is misleading when working with tungsten light.

Brandon Fraley
04-03-2009, 12:13 AM
So after finding out that both the Histogram and False Color are linked to the color space they are in and not the RAW exposure, I have been thinking about how to monitor better.

Last I checked, you can set the histograms to to either the current colorspace or RAW

EDIT: Yeah, use the RAW histogram rather than the RGB histogram. it analyses the RAW independent of which color space you're monitoring with.

Matthew Rogers
04-03-2009, 05:08 AM
Last I checked, you can set the histograms to to either the current colorspace or RAW

EDIT: Yeah, use the RAW histogram rather than the RGB histogram. it analyses the RAW independent of which color space you're monitoring with.

Thank you for reminding of that. It was mentioned last week in another thread but in my tired state last night I forgot. Now, if we can only get False Color to also go off the RAW in both REC709 and REDSpace.



What have monitor chroma saturation levels got to do with exposing accurately?

The saturation has nothing to do with exposure, but instead having a decent saturation amount for the client monitor-instead of a almost colorless image.

Matthew

Stuart English
04-03-2009, 06:18 AM
Now, if we can only get False Color to also go off the RAW in both REC709 and REDSpace.

The color coded vertical bar to the right of the histogram IS driven from RAW data.

Take a look how it does NOT change as you increase or decrease ISO values.

This is because its a RAW Exposure Meter.

Personally to do as you want, I'd be monitoring in REDspace and checking the combination of histogram and that RAW Exposure Mater.

David Wyatt
04-03-2009, 08:16 AM
What you could possibly do is monitor in Rec709 (which is closer to RAW than REDSPACE which is fairly heavily boosted, especially saturation-wise), but base your exposure on the histogram (set to RAW) and the RAW exposure meter (the rainbow/colour bar). Often this will mean the monitor image will look a bit hot & you'll get people querying whether the image is overexposed (if you're monitoring in REDSPACE this will be even more pronounced). Rather than spending the time explaining the difference between RAW and Rec709 etc etc, it might be a good idea to crank down the brightness on the monitor so it looks less hot/more normal. Now you should have a fairly decent monitor image for the director/clients while at the same time you're able to assess the exposure in the RAW world.

Matthew Rogers
04-03-2009, 09:38 PM
Or I could just crank down the exposure in REC709 also instead of on the monitor. It just would be VERY HELPFUL to be able to have False Color monitor in the RAW. Otherwise, it's really a worthless tool because while the raw exposure meter is nice (actually, that's a lie because I have no clue how to use it, and even then it doesn't do what I need) False Color does what I need. I want to know WHAT part of my image is at what exposure-not just knowing that things are clipping. Maybe I don't understand how to use the exposure meter, but since there's nothing much in the manual on how to use it I have to just guess.

Matthew

RED Army
04-11-2009, 12:08 AM
I tried setting the histogram to RAW. (Build 17). And when I change the ISO settings on the camera, the histogram changes as well. Which means that the Histogram RAW, really is not reading the RAW data but rather the LUT applied by 709 or RedSpace...

Anyone else find this to be true?

Eric Haase
04-13-2009, 09:44 PM
I just monitor in RAW and tweak my monitor so the image has contrast and saturation. Also, I change the color temp of the monitor (Panasonic LCD) to either D65 or D95 depending if I'm shooting with Tungsten or Daylight. I also tweak out the monitor gamma to my liking (FILM, VARICAM, etc). It's rather un-scientific but actually I've found this gives a much better idea of the image's potential over REDSPACE or REC709. This way I'm monitoring in the viewfinder the RAW image and light levels but clients are looking at a nice image on the monitor. One of the drawbacks is that of course you don't see any ASA (gain) adjustments or color temp/tint adjustments you're putting in the metadata. I try to take the approach like film in that I never intend to monitor a completely colored image on set. For years we looked at low contrast, off color video taps and they were fine. If a client has a question you can always pull up a clip on your laptop and do a quick grade to show everyone the idea.