Help with ETTR Please...

I am trying to get my head around and use ettr, i have been sellecting anything from +1/3-+1 ec, and today although using + 1 in poor weather and in sh priority, i was having to keep opening up my aperature till it reached 5.6 even though 400iso was selected by the camera, yet the meter kept saying - lo even with 125/sec sh speed, anyway when i processed my raws they where not showing any under exposure but just about spot on, my question is - why was lo showing even with ec of + 1 that created a good exposure.

Sorry for the stupid question just curious.

P.

To follow up the above, i have just been reading through the threads abaout HAMSTER, but to be honest im not sure if they relate to my question or infact if i have/am tottaly barking up the wrong tree and not applying ettr correctly? i use the auto Iso mode at the moment as it is quite accurate, but to help noise in areas where i have reached the limit of my sh speed and aperature, applying Ec may not being helping, and selecting an increse in my Iso but higher may help further?


P.

I'd go to https://photography-on-the.net …t=1356456&highl​ight=quick and pay particular attention to input #10 by amfoto1. Excellent writeup and likely will explain your issues.

John from PA wrote in post #16639712
I'd go to https://photography-on-the.net …t=1356456&highl​ight=quick and pay particular attention to input #10 by amfoto1. Excellent writeup and likely will explain your issues.

Hi, i think you miss-understood my post, i am on about exposing to the right(ETTR) for noise control uses, i have read about this in the posts on here tittled HAMPSTER, but i am not sure if they relate to my quiry.

P.

Not about using flash.


P.

Sorry, pagman.
I can't really understand your post.
It's all one long stream of words.
Try saying short sentences about what you are doing.
Separate them with full stops (periods).
If you want to ETTR , don't use Auto ISO.
Simply dial in +EC until the histogram hits the right hand edge...

ETTR may or may not need EC.
ETTR has everything to do with being able to read a histogram.
ETTR is just what it says: Expose To The Right.
ETTR may require under or over exposure depending on the scene.
ETTR is about extracting all of the dynamic range a sensor can capture.

Just dialing in +1/3 or +1 isn't necessarily going to expose to the right.
It could take just about any amount of compensation, including negative compensation in very bright scenes. The amount of exposure is completely dependent on the scene, snow for example almost always requires + compensation.

Your meter is trying to meter the scene for a neutral light gray. Because the meter is looking for light gray, many scenes can fool the meter and be under or overexposed. No set amount of EC will render a scene ETTR, it's different for each one. Reading your histogram is the only way to determine the exposure for a particular scene.

casaaviocar wrote in post #16639845
ETTR is about extracting all of the dynamic range a sensor can capture.

I know this is a pagman thread. And your post is a good one, but I wanted to correct something, because this simply isn't true. ETTR is about trading dynamic range for lower noise. If you ETTR 1 stop, you lose 1 stop of dynamic range. The bottom stop (or left if you're looking at a histogram) will be lost when you move the exposure to the left a stop to correct the exposure for the HAMSTER.

vengence wrote in post #16640038
I know this is a pagman thread. And your post is a good one, but I wanted to correct something, because this simply isn't true. ETTR is about trading dynamic range for lower noise. If you ETTR 1 stop, you lose 1 stop of dynamic range. The bottom stop (or left if you're looking at a histogram) will be lost when you move the exposure to the left a stop to correct the exposure for the HAMSTER.

I'm not sure I follow here. The basic idea of ETTR as I understand it is to push the histogram as far to the right as possible without clipping highlights. This should result in optimal DR.

Suppose you're shooting a relatively dark scene (e.g., outdoors at twilight), but one whose total DR is within the sensor's capability. If you expose "correctly" to make the scene look realistically dark SOOC, then you're unnecessarily putting the darkest parts of the shadows beneath the noise floor. If you ETTR, the scene will look brighter than reality SOOC, but you can compensate in post while also having more shadow detail available.

The only time you "lose 1 stop of DR" is if you clip the highlights in a situation where the shadows were already above the noise floor, which goes against the spirit of ETTR.

EDIT: OK, I think I see what you're saying now. However, it assumes you're simply going to load the file into LR, jerk the exposure slider to -1.00 and be done with it. As long as you're willing to do a bit more work in PP (even as simple as using the Shadow/Fill Light slider after dialing in -1.00), ETTR should still give optimal image quality without impacting DR.

You beat me to it Brett. I was just about to answer in the same vein. I do agree with vengence in the statement I made: "ETTR is about extracting all of the dynamic range a sensor can capture" is a by-product of controlling noise. ETTR is ultimately about less noise, and noise is most noticeable in the shadows, so moving the exposure to better expose the shadows will reduce noise. I look at ETTR as more of a DR tool, allowing me to get the best exposure of the whole scene, but vengence is right, it is about noise, and I misspoke there. But as to loss of DR, I disagree with vengence. By placing my highlights against the right side of my Histogram at any time I have extracted the maximum DR my sensor can handle.

If I have to move the histogram to the left to maintain highlight detail, (not sure if this is what vengence is suggesting in the post, there is talk of ETTR 1 stop, and I take this to mean + compensation, but then there is talk of moving the histogram left and that means - compensation) I do possibly lose some shadow detail, but in preserving the highlights with that move left, I still have extracted all of the possible DR my sensor can capture, I've just had to make a choice as to what to lose, the scene just exceeds the capacity of my sensor, but I've still captured the maximum DR my sensor can capture.

Yeah, I think it's important to clarify that ETTR is primarily a rule to use when the DR of the scene is smaller than your sensor's DR. To put it in layman's terms: "if your histogram is bunched up anyway, you might as well shift it over to the right side to minimize noise."

If you're shooting a scene with large DR, then you simply have to make a choice between either clipping the highlights or incurring unacceptable shadow noise. In such cases, ETTR doesn't really apply, other than to say it would be foolish to have the highlights any farther left than the right edge of the histogram.

Technically, you are correct, but sometimes there are highlights you can sacrifice (reflections of the sun on glass, chrome etc). The histogram will show them as a spike, but they are not worth preserving to the detriment of your DR.

To get back to pagman:
You need to understand that ETTR says that the brightest tone in your image (other than specular highlights) should be captured just short of clipping. That may not be "proper" or "accurate" exposure in the traditional film-based definition of good exposure which was about placing middle tones, but it is the best exposure for digital photography because it maximizes the data captured. You accomplish this by adjusting shutter speed or aperture and you know how much to adjust them by watching the histogram. HAMSTTR says that if you don't want to increase either of those variables, it is still worthwhile to bring the values in the Raw file close to the maximum by increasing ISO. That means that you cannot use Auto ISO, you have to control it. This advice is appropriate for Canon cameras because increasing camera ISO (up to the limit of analog ISOs) causes less of an increase in noise than the reduction in noise obtained by pulling down the tonality in the Raw converter, so there is a net improvement. But it may not be true of other cameras in which there is more of a noise increase as ISO goes up. I don't know how HAMSTTR would work on your camera.

tzalman wrote in post #16640471
To get back to pagman:
You need to understand that ETTR says that the brightest tone in your image (other than specular highlights) should be captured just short of clipping. That may not be "proper" or "accurate" exposure in the traditional film-based definition of good exposure which was about placing middle tones, but it is the best exposure for digital photography because it maximizes the data captured. You accomplish this by adjusting shutter speed or aperture and you know how much to adjust them by watching the histogram. HAMSTTR says that if you don't want to increase either of those variables, it is still worthwhile to bring the values in the Raw file close to the maximum by increasing ISO. That means that you cannot use Auto ISO, you have to control it. This advice is appropriate for Canon cameras because increasing camera ISO (up to the limit of analog ISOs) causes less of an increase in noise than the reduction in noise obtained by pulling down the tonality in the Raw converter, so there is a net improvement. But it may not be true of other cameras in which there is more of a noise increase as ISO goes up. I don't know how HAMSTTR would work on your camera.

This is an interesting subject to me. Is there a video or tutorial on ettr and using the histogram? I would like to learn more in depth of how to get the perfect exposure.

Pagman wrote in post #16639729
Hi, i think you miss-understood my post, i am on about exposing to the right(ETTR) for noise control uses, i have read about this in the posts on here tittled HAMPSTER, but i am not sure if they relate to my quiry.P.

So right, saw ETTR and this 70 year old brain equated that to ETTL.

Sorry.