How do you ETTR?

unpopular · Jul 8, 2013

When you ETTR, do you predefine how much more exposure you'll add? Do you use trial and error/guesswork/estimation to keep the hilights from clipping? Do you meter in any specific way, or in a similar way as you would normally?

jaomul · Jul 8, 2013

[SUP][/SUP]I usually just dial in 1/3 plus exposure up to mid range iso values and 2/3rds plus when iso is high. I find with canon these values usually dont clip and I rarely push photos in post

amolitor · Jul 8, 2013

Don't you normally spot meter the brightest thing in the scene, and expose to place that in the rightmost position? Are you asking "ok, so how many stops up is that from middle grey"? I think the answer more or less has to be "experiment and find out where the highlights start to fall apart in your particular combination of camera, sensor, and software" but heck if I can be bothered to look it up.

ETTR is for people who would have been Zone System people in an earlier era.

cgipson1 · Jul 8, 2013

If I want ETTR, I will spot meter various areas until I get the Histogram I want. And I will bracket also just to make sure.

Gavjenks · Jul 8, 2013

You should be able to figure this out before you head into the field.

Shoot images of a uniform white piece of computer paper or whatever, and dial in compensation values until it is about 1 stop shy of being blown out. Then, when you want to to ETTR in the field, set your compensation to exactly that number, and spot meter the brightest thing in your composition.

unpopular · Jul 8, 2013

amolitor said:
Don't you normally spot meter the brightest thing in the scene, and expose to place that in the rightmost position? Are you asking "ok, so how many stops up is that from middle grey"? I think the answer more or less has to be "experiment and find out where the highlights start to fall apart in your particular combination of camera, sensor, and software" but heck if I can be bothered to look it up.

ETTR is for people who would have been Zone System people in an earlier era.

Gavjenks said:
You should be able to figure this out before you head into the field.

Shoot images of a uniform white piece of computer paper or whatever, and dial in compensation values until it is about 1 stop shy of being blown out. Then, when you want to to ETTR in the field, set your compensation to exactly that number, and spot meter the brightest thing in your composition.

Yes. I know how to ETTR, or at least what I call ETTR, and this is how I ETTR, but I want to know how others do it. Obviously if most people out there are metering the hilights, then my arguments about the arbitrariness of ETTR are invalid.

Thanks for your participation

unpopular · Jul 8, 2013

amolitor said:
Don't you normally spot meter the brightest thing in the scene, and expose to place that in the rightmost position? Are you asking "ok, so how many stops up is that from middle grey"? I think the answer more or less has to be "experiment and find out where the highlights start to fall apart in your particular combination of camera, sensor, and software" but heck if I can be bothered to look it up.

+2.6 to Zone IX using most lenses

ETTR is for people who would have been Zone System people in an earlier era.

Yes. I've even developed a method to compensate shadows using gamma, but it's not very practical.

amolitor · Jul 8, 2013

Yeah, ETTR *should* be "expose for the highlights, convert for the shadows". I dunno how much of that actually translates, though. Me? I just do what the damn meter tells me to do, occasionally with a little fudgement applied. Then I saw 'WOO HOO! RAW! +/- a stop no problem, +/- two if I accept some.. issues.. why would I worry about exposure?!'

unpopular · Jul 8, 2013

It just seems like when people discuss ETTR they kind of have this really imprecise approach to it, you hear a lot of "slightly over expose" or "increase by +1/3" ... stuff like that.

I'm a total exposure control freak, probably excessively so, so this doesn't set so well with me.

amolitor · Jul 8, 2013

Yeah. I dunno, some people can do really precise and careful things but can't talk about it coherently. I suspect a lot of religious fervor without much understanding, though. Look at the number of people who "shoot manual" by simply meter matching. Lot of Cargo Cults in photography. Always have been, always will be.

KmH · Jul 8, 2013

Don't concern yourself with specular highlghts - http://en.wikipedia.org/wiki/Specular_highlight

Don't confuse specular highlights with specular reflections - Specular reflection - Wikipedia, the free encyclopedia

unpopular · Jul 8, 2013

^^ I know we've been over this, and I have come to agree with you. You are absolutely right on that point. Never meter hilights with a direct angle of incidence else everything will be too dark (except the specular, of course!)

In fact, really it only makes sense to meter the brightest region with detail. No sense in metering Zone X.

Big Mike · Jul 8, 2013

I don't spot meter anything...Heck, I can barely remember which icon is which when it comes to metering modes.
I do chimp the histogram, and if I notice that when I have the exposure that I want...I still have room to the right, then I'll add some exposure...probably 1/3 to a full stop...

It is certainly important to know how to read a histogram, which means recognizing what detail is important and what isn't...specular highlights & reflections etc...as mentioned above.

Also, remember that the histogram on the camera, is based on the JPEG (preview if shooting RAW). So it's not worth being super attentive to exactly what is clipping and what isn't...because the raw file likely has more latitude. After working with the same camera & software for a while, you can really start to get a feel for it.

I teach my students about ETTR and explain the s/n ratio...but I really use it as an example of why it's so bad to underexpose your photos (and then have to fix them in post).

pgriz · Jul 8, 2013

I've used the magic lantern firmware add-on to my T1i which has the option of reading out the value of a spot-meter reading. One of the options allows me to set it to show any value between 0 and 255. I've checked it by seeing the value I get after uploading and it's pretty much bang on. So if I have to be sure that I get something that's bright, yet with detail, I adjust the exposure until the spot-meter (on the highlight) reads about 240 (+/-5), and I know that this "highlight" will have detail.