Luminous Landscape Forum

Equipment & Techniques => Digital Cameras & Shooting Techniques => Topic started by: ygor on August 20, 2013, 08:57:30 am

Title: UniWB+ETTR (Photo) and Technicolor
Post by: ygor on August 20, 2013, 08:57:30 am
I know Technicolor profile doesn't affect the RAW file, but I'm used to keep it set up by default on my 7D mainly because of video shooting.

My doubt is: does Technicolor have any implication on the reliability of the UniWB+ETTR histogram? If so, which color profile would be better for use with UniWB+ETTR (Neutral, Faithful etc.)?

Any help would be very welcome, I didn't find any solid info over the Internet about it.
Title: Re: UniWB+ETTR (Photo) and Technicolor
Post by: Vladimirovich on August 20, 2013, 10:34:16 am
any implication on the reliability of the UniWB
if you are talking about in camera jpg based per channel RGB histogramm for UniWB-based estimation of raw channels clipping (how close you are/etc) then you probably want as "wide" colorspace for your in camera JPG as possible (AdobeRGB,  instead of sRGB) and as flat curve (less contrast) as possible.

PS: are Canon users not graced w/ custom firmware addon (Magic Lantern) that provides true raw histogram, are they ?
Title: Re: UniWB+ETTR (Photo) and Technicolor
Post by: ygor on August 20, 2013, 10:40:40 am
Exactly. That's why I asked, because Technicolor has a very low contrast, flat profile.
Title: Re: UniWB+ETTR (Photo) and Technicolor
Post by: Vladimirovich on August 20, 2013, 10:59:17 am
Exactly. That's why I asked, because Technicolor has a very low contrast, flat profile.
but in any case you shall run some tests to learn how your jpg based RGB histogram (or rather the parts on the right side) on camera's LCD corresponds w/ raw histogram (using rawdigger for example) in terms of headroom to clipping.
Title: Re: UniWB+ETTR (Photo) and Technicolor
Post by: ygor on August 20, 2013, 02:15:49 pm
Good tip. I'll try this ASAP.
Title: Re: UniWB+ETTR (Photo) and Technicolor
Post by: ygor on August 21, 2013, 08:29:03 am
I did some tests yesterday, and my conclusion was that any Color Profile other than Canon's Standard (the default one) isn't reliable for UniWB+ETTR. I tested Standard, Neutral, Faithful and Technicolor Cinestyle. Technicolor is the flattest of them, making green and blue clip easily if exposed to the right up to the limit on 7D. Thus, the worst in this case. Neutral and Faithful were close to RAW histogram, but still not identical.

Standard reflected 100% of the histogram on camera LCD, being the best one.
Title: Re: UniWB+ETTR (Photo) and Technicolor
Post by: ygor on August 21, 2013, 08:33:08 am
PS: are Canon users not graced w/ custom firmware addon (Magic Lantern) that provides true raw histogram, are they ?

Yes, we are, and I've already tested it. But ML on 7D has some battery bugs that are not further investigated by them yet. I have the big risk of getting battery drained really fast. So for now, I'm not going to use it.