ETTR and ISO

[MikeZ]

I saw this video from Steve Perry (I know, he's Nikon centric, but the info is non-manufacturer specific) regarding exposing for highlights or shadows. He makes an interesting argument about the exposure triad - shutter speed, aperture and ISO - and how we treat ISO. Seems, according to Perry, that that the noise is always present and raising ISO only highlights it. He does a better job of explaining it, so watch the video .

 

[Dave Williams]

I'm not in the least bit technical but all the examples of noise comparison he makes are at very low shutter speeds. if you want to shoot action you can't work with 1/50th of a second. If you are using an f5.6 lens that's as wide as it goes so no option there either.
I don't quite understand what he's trying to say to be honest!

 

[TwoWheeler]

So I slowed my shutter speeds and opened my apertures just like he said…and now my images are blurry and have no depth of field, but by god they’re not noisy!

Truth be told, I never paid any attention to ETTR and little-to-no attention to ISO. Aperture and shutter speed are going to be what they need to be to make the shot work and ISO is going to be whatever it needs to be to get exposure right.

 

[Only RF]

Yep. I came across that video the day he released it. He is basically saying don't use ISO to compensate for noise. With a proper exposure higher ISO's will produce a decent result.

 

[StevenAunan]

I watched that the other day, and what I gather is that we should just take photographs in the way we took photographs before the ISO revolution. I find it hard to disagree.

 

[ctitanic]

I'm not in the least bit technical but all the examples of noise comparison he makes are at very low shutter speeds. if you want to shoot action you can't work with 1/50th of a second. If you are using an f5.6 lens that's as wide as it goes so no option there either.
I don't quite understand what he's trying to say to be honest!

Correct. I left him a comment that the video was good but almost impossible to apply to wildlife photography. His response was that the purpose of the video was to show the importance of properly exposure your picture "instead of ETTR".

 

[Dave Williams]

Correct. I left him a comment that the video was good but almost impossible to apply to wildlife photography. His response was that the purpose of the video was to show the importance of properly exposure your picture "instead of ETTR".

ETTR is another aid not a guarantee of correct exposure.
At least he wasted more time making the video blog than I did watching it.

 

[David Berry]

I too found the video unnecessarily complicated and consequently thoroughly confusing. (Ease up on the smoke and mirrors, Steve.)

ETTR is a useful technique for avoiding excessive noise in the dark areas of an image. That’s its purpose (for me, anyway!).

Noise in dark areas is the result of too little light (too few photons) reaching the sensor. To avoid this noise, increase the amount of light reaching the sensor. Give the sensor a bigger helping of photons!

There are TWO (not three!) ways of increasing the quantity of light reaching the sensor:

1. Lengthen the exposure time — Tv
2. Increase the aperture — Av.

Increasing ISO does NOT increase the amount of light reaching the sensor and, therefore, doesn’t get rid of that pesky low-light noise.

… David

 

[Only RF]

Thinking on this a bit. I shoot in M mode so EC is assigned to ISO. With a slow lens like the 100-500 many times you can't use that. Losing two stops of shutter speed can also cross that make or break threshold. When I don't have time to meter shooting into the sky I add at least ¾ to 1 stop of EC. Not sure how much that really affects things. Avoiding noise whenever possible is the key but with modern NR apps it's less of an issue.

 

[Dave Williams]

So, what I have gathered from this thread so far is the following, please correct me if I'm wrong.

The original video is trying to demonstrate that the noise is always there, it's a question of how visible it is.
Using film, the light sensitivity differs from roll to roll. In camera bodies it differs from model to model depending on the sensor used.
The fewer and bigger the pixels the camera has the more light they collect. Shutter speed and aperture are the only means of increasing or decreasing light hitting the sensor .
The set ISO indicates the amount of light that the sensor is receiving as indicated by the light meter and relative to the applied shutter and aperture set.
If you expose to the right the dark areas of the shot appear lighter and show more detail but if you over do it the whites get blown beyond retrieving and all detail is lost .
If you expose to the left of the histogram detail is lost in the shadows. Increasing the exposure in post processing reveals the noise that's hidden in the dark areas.

That seems pretty clear, to me anyway. It's what I have always worked with and I have always used manual mode settings in camera.

Now, what about exposure compensation?
How does that make a difference or is that just showing you the result at the current settings of shutter speed and aperture when you deliberately want to expose to the right?


and then we come to the effects of the number of and pixel size and data collection abilities.
Time to lie down in a darkened room for a while!

 

[Only RF]

I just find it easier and with one body quicker to use EC. While at first (like some others) I didn't like the location of the QC wheel on the R7. I really like it now. I find getting my thumb down to the one on the R6II and other bodies I've owned a little more awkward.

My #1 curse has always been ISO. Shooting BIF and a smaller bird lands in a tree. Often I used a way to high of an ISO. I mapped C1-3 for different shutter speeds. 1 being low for perched birds, 2 for slower moving animals for like a bird in water and 3 for BIF. I then will also tweak the shutter and use EC as needed.

I'm not so sure I want to change that. I have really warned up to M mode and Auto ISO.

 

[David Berry]

I mapped C1–C3 for different shutter speeds. 1 being low for perched birds, 2 for slower moving animals for like a bird in water and 3 for BIF.

• That's a very good idea.

I then will also tweak the shutter and use EC as needed.

1. Exposure compensation, when coupled to ISO, will affect (lighten/darken) an image.
2. Exposure compensation, when coupled to ISO, will NOT affect (decrease/increase) noise.

Point #2 is the main message of Steve Perry's video: unfortunately, it's swamped by his complicated explanations.

 

[Only RF]

• That's a very good idea.

1. Exposure compensation, when coupled to ISO, will affect (lighten/darken) an image.
2. Exposure compensation, when coupled to ISO, will NOT affect (decrease/increase) noise.

Point #2 is the main message of Steve Perry's video: unfortunately, it's swamped by his complicated explanations.

Thanks Dave. I figured I was OK until he made me think about it.

Some like to use C1-3 for different scenarios like animals, people or landscape. I used to do that but now I just assigned those things to the Green menus. Works for me because I don't change subjects that much, especially with the R7. With C1-3 the only thing that changes is SS so I have consistency with all the mapped buttons. That is the one main thing I miss about the R5. I could map C1-3 to a button. I can map subject to detect with the R6II. My R5 never had that.

 

[MikeZ]

I think that Dave Williams in post 10 has summed-up the video. The take-away is that noise in an artifact of the sensor, it is always there and just becomes more visible with increased ISO. I suppose we just need to use whatever ISO works for the situation at hand and denoise.

1. Exposure compensation, when coupled to ISO, will affect (lighten/darken) an image.
2. Exposure compensation, when coupled to ISO, will NOT affect (decrease/increase) noise.

I agree with this, and I'm confused over the use of EC when in manual mode. What exactly does EC modify in that mode? You have set both the aperture and the shutter speed, so is EC changing one of those or is it adjustinging the ISO to increase or decrease the exposure?

 

[Only RF]

I think that Dave Williams in post 10 has summed-up the video. The take-away is that noise in an artifact of the sensor, it is always there and just becomes more visible with increased ISO. I suppose we just need to use whatever ISO works for the situation at hand and denoise.


I agree with this, and I'm confused over the use of EC when in manual mode. What exactly does EC modify in that mode? You have set both the aperture and the shutter speed, so is EC changing one of those or is it adjustinging the ISO to increase or decrease the exposure?

That is what it does. If you look in the EVF or LCD when you adjust EC only the ISO changes. Aperture and SS stay the same which is what I want to happen. If I'm shooting a fast bird I don't want to slow down the SS. In manual ISO that would work but then I may get motion blur. With Auto ISO my SS stays the same.

 

[ctitanic]

I think that the main problem with his video is that everybody associates him with being a wildlife photographer and what he showed in his video demand changes that rarely can be used in wildlife photography (the use very low Shutter Speed).

The way I shoot and works for me is:
1- Having C1 configured for perched birds with AP, Auto ISO, minimum SS of 1/500 and using EC as needed.
2- Having C3 configured for BIF or any type of action with Shutter Priority set at 1/3000, Auto ISO, minimum SS of 1/500 and using EC as needed.

With 2 clicks of my thumb I switch from C1 to C3 or vise-versa. I could have the C1 with M and Auto ISO. That will work perfectly for me too. I just feel that I have used the C1 in AP for so long that M will make me retrain my brain to the new configuration and I'm all for enjoying the moment without tormenting myself by thinking too much.

EC is something that I constantly use and by default I have it set slightly to the right. If shooting white birds or white flowers then I move it to the right one or two stops depending on the conditions.

When shooting Sport sometimes or most of the time I switch to Full Manual or Manual with Auto ISO.

When shooting events with Flash I normally shoot in M. I control the ambient light with the camera settings and using the flash in TTL mode I use the EC of the flash to control the subject exposure.

If I would dedicate myself to Studio photography (portraits) I for sure would use Manual. For sure, but I do not have a Studio neither I'm a professional photographer.

In the last two years I have became less worry about ISO and noise. There are many software out there that help to control noise in your pictures and at the same time Canon Mirrorless cameras are now handling noise a lot better.

This is what works for me... All roads lead to Rome.

 

[David Berry]

I'm confused over the use of EC when in manual mode. What exactly does EC modify in that mode?

When mode is set to M (“Manual with Auto ISO”) the defaults are:

• Tv : manual
• Av : manual
• ISO : auto
• EC : adjusts ISO

It is possible to set ISO to manual (“Full Manual”) with the following defaults:

• Tv : manual
• Av : manual
• ISO : manual
• EC : not adjustable, but EC in EVF and rear screen will indicate over/under exposure.

… David

 

[Dave Williams]

Just checked and at first exposure compensation made no difference to ISO in M mode because I had set the maximum ISO too low. Now I have changed it that’s what it does. However, this has now gone a complete circle. Using auto-iso and plus EC ( ETTR!) reduces visible noise

 

[Only RF]

Well too bad this one was a bit confusing. I have several of his videos linked. I purchased his LrC/PS NR reduction video set. Very handy method before Adobe came out with Denoise AI.