@bdegazio
OK, I get what you're saying. So his tests were about noise, where there's no advantage, whereas the real issue is the variety of colours and chroma available for each stop in the frame. I'd love to see a test as thorough as the above article, but with colour levels - a real world (yet scientific) test!

@nomad Is it not true that it should work with 8 bit as well as with 12 bit. The number of available levels is already reduced, but accessing more (in the brighter end of the histogram) makes sense, no? (Perhaps with 12 bit, it could be said to be less relevant, as there are so many more levels within every stop to begin with.)

OK. I completely get it. I'm on board. I now also understand why, LPowell, you have mentioned several times in the GH1 hack threads that high exposure is more likely to cause high data rates and hence crashes - the big data capture is all pressed up to the right.

For a few years I had a 5D Mk1 that I absolutely LOVED for RAW stills work, and I have one image that I always regarded as supreme, above all others I've taken, that I always show to demonstrate the brilliance of the camera (with a Zeiss 50mm) - I just checked in Aperture (an awesome Apple app. by the way) and yup, the master file is WAAAY over-exposed, with what appears to be blown out highlights, but on the adjusted version, it's simply perfect. I have a real world verification of something that isn't placebo, or too subtle to notice but simply better.

So, LPowell, would you agree that ETTR has a place in 8 bit acquisition? It seems even more so than in RAW, to me.

@LucasAdamson - "would you agree that ETTR has a place in 8 bit acquisition?"

Yes, the fewer bits you have to work with, the more important it is to make optimal use of them.

I think ETTR explains why highlight roll-off can be a good thing. Often 8-bit depth won't give enough DR. Then we gotta decide either overexpose or underexpose. I prefer slight overexposure if ISO can stay low enough. That feels like walking on thin ice :)

I'd determine aperture and shutter speed. Then ISO varies up to a limiter. Comfortably up to 800. Maybe 1250.

But I don't want to stick to ETTR all the time. Sometimes it's nice to do underexposing to give a proper mood.

Even if there is enough lighting to keep ISO low, sometimes the source clips still look crappy. I think that's when ETTR can shine.

Guys, sorry for the silly question, but I've never really much used anything other than standard and I've been using lighting / reflectors to control DR, together with making adjustments in post.

Last night I was attempting to shoot the moon through a telescope and using various other lenses, and it was varying quite a lot as the clouds passed in front of it (nice effect though). Because the brightness was going up and down I simply couldn't arrive at an exposure which worked at both "ends" of the scale, ie to show the details on the bright surface when there weren't any clouds, and at the other end, to show the dim moon with the clouds around it, lit up. That's a scenario with a huge dynamic range, and I discovered that because I couldn't capture the extremes well, it was pretty much impossible to do anything with the images afterwards.

So are there good in-camera settings that give a bit more highlight / lowlight compression for contrasty subjects so you can get the best out of the 8 bits available? I know, I can experiment, but some of you must be more familiar with the various presets on the camera than I am and I was hoping you could suggest what to try.

The one good thing about my Canon XHA1 was its comprehensive menus for highlight and lowlight compression but because the GH2 is so good anyway, I haven't particularly had issues with using Standard up till now. And unfortunately the moon scenario isn't one I can control with lighting or reflectors!

@LPowell, I have an upcoming short, shooting on GH1s with Peak Reliability patch (thanks btw) for a film we want to be b&w. Would shooting in camera B&W improve levels of chroma available, or just reduce bitrate?

@LucasAdamson
In B&W film mode, the AVCHD encoder will store minimal data in the two chroma channels and record the luma channel as usual.

Here's an interesting article on TOP by Ctein that calls bullshit on the ETTR rule

http://theonlinephotographer.typepad.com/the_online_photographer/2011/10/expose-to-the-right-is-a-bunch-of-bull.html

I love this comment on that article: "I have learned to expose the subject right."

Well it certainly does as far as exposure is concerned. With digital just like with slide you expose for the highlights and fill for shadows. With negative you expose for shadows and develop for your highlights.

Well, as a general rule, I do think usually about saving highlights shooting video, same as we used to do with Kodachrome, etc. You can pull up noisy blacks but you can't usually pull back blown whites.