Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version 18 Likes Search this Thread
12-25-2020, 04:46 PM   #1
Site Supporter
Site Supporter




Join Date: Oct 2017
Location: Lancaster
Photos: Gallery
Posts: 3,829
Ettl vs ettr

I, for my sins, expose to the left of my histogram. My process is to spot meter on what I perceive to be a mid tone, lock it in and recompose. My Exposure comp is generally around minus one (something I am going to try dropping from tomorrow). The purpose is to avoid blowing my highlights whilst protecting shadow detail but recently I have become increasingly dissatisfied with the exposure. So, seeking enlightenment I consulted the wise photo wizards in YouTubeland and came out even more confused. One said exposing to the right gives you smoother tonal transmission so we should always expose right! The next claimed better dynamic range can be achieved by exposing left. The third was more of a horses for courses type, suggesting left for high key scenes and right for low key (which kinda made sense, keeping away from the extremes) the question is does anyone have a magic formula? (Other than move somewhere sunny, which I have considered, Cádiz is rather splendid). The images here are always so beautifully exposed, I am hoping one of you will give up your secrets, it being Christmas and all that? ..... maybe?

12-25-2020, 05:00 PM   #2
Site Supporter
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Washington Cascades
Photos: Gallery | Albums
Posts: 12,992
I think part of the confusion is different people using the same terminology but meaning different things.

This is my version of expose to the right:
Adjust compensation so that areas that are pure white are just barely blown out. My quick and dirty solution is to take an exposure and check the screen with the blinkies on. If I see just a few blinkies in areas like bright clouds or light fixtures then I know I'm good. Just a few, not much, just a couple of red dots.

That system tells me I have exposed as far to the right as I can without blowing out significant highlights. Shooting in RAW I can recover those few dots. And that gives me the brightest exposure possible in the dark areas. If that still doesn't cover the dynamic range then multiple exposures and blending in post are required.

YMMV but that works for me. I do not pretend that is the only system or even the best but its what I use and it has generally worked well for me.
12-25-2020, 05:10 PM   #3
Site Supporter
Site Supporter




Join Date: Oct 2017
Location: Lancaster
Photos: Gallery
Posts: 3,829
Original Poster
QuoteOriginally posted by jatrax Quote
I think part of the confusion is different people using the same terminology but meaning different things.

This is my version of expose to the right:
Adjust compensation so that areas that are pure white are just barely blown out. My quick and dirty solution is to take an exposure and check the screen with the blinkies on. If I see just a few blinkies in areas like bright clouds or light fixtures then I know I'm good. Just a few, not much, just a couple of red dots.

That system tells me I have exposed as far to the right as I can without blowing out significant highlights. Shooting in RAW I can recover those few dots. And that gives me the brightest exposure possible in the dark areas. If that still doesn't cover the dynamic range then multiple exposures and blending in post are required.

YMMV but that works for me. I do not pretend that is the only system or even the best but its what I use and it has generally worked well for me.
So, you go right ish. That is what I was thinking of trying tomorrow. Do you know if leaning left or right of centre has a detrimental effect on dynamic range? Or are we talking about variations that are so small they aren’t noticeable?
12-25-2020, 05:11 PM - 2 Likes   #4
Moderator
Loyal Site Supporter




Join Date: Apr 2014
Location: Baltimore
Photos: Albums
Posts: 3,400
QuoteOriginally posted by Cerebum Quote
I, for my sins, expose to the left of my histogram. My process is to spot meter on what I perceive to be a mid tone, lock it in and recompose. My Exposure comp is generally around minus one (something I am going to try dropping from tomorrow). The purpose is to avoid blowing my highlights whilst protecting shadow detail but recently I have become increasingly dissatisfied with the exposure. So, seeking enlightenment I consulted the wise photo wizards in YouTubeland and came out even more confused. One said exposing to the right gives you smoother tonal transmission so we should always expose right! The next claimed better dynamic range can be achieved by exposing left. The third was more of a horses for courses type, suggesting left for high key scenes and right for low key (which kinda made sense, keeping away from the extremes) the question is does anyone have a magic formula? (Other than move somewhere sunny, which I have considered, Cádiz is rather splendid). The images here are always so beautifully exposed, I am hoping one of you will give up your secrets, it being Christmas and all that? ..... maybe?
IMO...

ETTR is what we should be doing generally, because by doing so we capture the most data and the least noise. The problem is, ETTR gets you into dangerous territory with blowing highlights----which I think most people consider more problematic than impenetrable shadows. Blown highlights always look "blown", but a lot of times very very blacks can read ok in an image.

Here in Pentax land, the problem is further compounded by Pentax's penchant for seemingly hard cutoffs at the highlight end, but OTOH remarkable shadow recovery. I wish someone who knows more than I do would write about this.....thus we have this feeling for ETTL.

Really, it should always be ETTR-AFAYC(As Far As You Can), which for Pentax cameras seems to be less TTR than with Canon cameras. So: you've got to know your equipment. I seem to recall from years ago that a lot of this ETTR business came out of Luminous Landscape, and Michael Reichman, the founder, was a Canon guy. It seemed to spread from there, IIRC.

12-25-2020, 05:16 PM   #5
Site Supporter
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Washington Cascades
Photos: Gallery | Albums
Posts: 12,992
QuoteOriginally posted by Cerebum Quote
Do you know if leaning left or right of centre has a detrimental effect on dynamic range?
I don't "know" much of anything. But my reading from various people indicates that if you expose to the right you maximize the amount of data recorded. The brightest part of the image records more tonal values thus expanding dynamic range and reducing noise.

Here is a quote from the Wikipedia article:
QuoteQuote:
ETTR was initially espoused in 2003 by Michael Reichmann on his website, after purportedly having a discussion with software engineerThomas Knoll, the original author of Adobe Photoshop and developer of the Camera Raw plug-in.[1] Their rationale was based on the linearity of CCD and CMOS sensors, whereby the electric charge accumulated by each subpixel is proportional to the amount of light it is exposed to (plus electronic noise). Although a camera may have a dynamic range of 5 or more stops, when image data is recorded digitally the highest (brightest) stop uses fully half of the discrete tonal values.
Considering the people who suggest using ETTR include Michael Reichmann and Thomas Knoll I go with ETTR as I assume they "know" a lot more than I do.
12-25-2020, 05:19 PM   #6
Site Supporter
Site Supporter




Join Date: Oct 2017
Location: Lancaster
Photos: Gallery
Posts: 3,829
Original Poster
QuoteOriginally posted by texandrews Quote
IMO...

ETTR is what we should be doing generally, because by doing so we capture the most data and the least noise. The problem is, ETTR gets you into dangerous territory with blowing highlights----which I think most people consider more problematic than impenetrable shadows. Blown highlights always look "blown", but a lot of times very very blacks can read ok in an image.

Here in Pentax land, the problem is further compounded by Pentax's penchant for seemingly hard cutoffs at the highlight end, but OTOH remarkable shadow recovery. I wish someone who knows more than I do would write about this.....thus we have this feeling for ETTL.

Really, it should always be ETTR-AFAYC(As Far As You Can), which for Pentax cameras seems to be less TTR than with Canon cameras. So: you've got to know your equipment. I seem to recall from years ago that a lot of this ETTR business came out of Luminous Landscape, and Michael Reichman, the founder, was a Canon guy. It seemed to spread from there, IIRC.
Interesting reply, thanks I guess it is akin to getting as close as you can to the cliff edge to get the best view possible. One step too far and .......... life on the edge well, in for a penny ....

---------- Post added 12-25-20 at 05:21 PM ----------

QuoteOriginally posted by jatrax Quote
I don't "know" much of anything. But my reading from various people indicates that if you expose to the right you maximize the amount of data recorded. The brightest part of the image records more tonal values thus expanding dynamic range and reducing noise.

Here is a quote from the Wikipedia article:


Considering the people who suggest using ETTR include Michael Reichmann and Thomas Knoll I go with ETTR as I assume they "know" a lot more than I do.
I am beginning to suspect that by asking this question, my shooting style is going to change significantly. Thanks for this. Very interesting
12-25-2020, 05:24 PM   #7
Site Supporter
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Washington Cascades
Photos: Gallery | Albums
Posts: 12,992
QuoteOriginally posted by texandrews Quote
ETTR-AFAYC(As Far As You Can),
That is a good way to put it, though perhaps a bit wordy I've used ETTR (as I see it) on Pentax gear since day one. I have had several arguments with various people loudly proclaiming that ETTR leaves you with blown highlights and that is stupid, etc. And in some cases that I was stupid, etc. Trying to convince them that ETTR is really ETTR-AFAYC was seemingly a waste of time.

Anyway, As Far As You Can is what I do. By having just a couple of tiny areas blown out I know I have gone as far as I can to the right and thus I have lifted the shadows as far as possible. That gives me the best possible image to work with in post. YMMV.

Perhaps it should be noted that just cranking the ISO up to achieve ETTR is self defeating. By increasing the ISO we increase the noise that we were shooting ETTR to reduce.

12-25-2020, 06:38 PM - 2 Likes   #8
Moderator
Loyal Site Supporter
Loyal Site Supporter
pschlute's Avatar

Join Date: Mar 2007
Location: Surrey, UK
Photos: Gallery
Posts: 8,219
I take a simplistic view on this. For a general scenes with both bright and dark areas I expose so that the highlights are not clipped, and let the shadows fall where they fall. I always use raw so can bring out detail in the shadows if I wish when processing the image.

If I specifically want to record shadow detail while keeping the highlights from blowing I bracket my exposures and do a HDR merge in post.
12-25-2020, 07:00 PM   #9
Site Supporter
Site Supporter




Join Date: Aug 2018
Location: Arkansas, USA
Posts: 1,169
I normally just go with the average meter reading and don't worry too much about ETTL or ETTR. As long as there is not a large dynamic range there's normally not a problem. This is shooting RAW of course.
12-25-2020, 08:28 PM - 2 Likes   #10
Pentaxian




Join Date: May 2009
Location: Somewhere over the rainbow
Photos: Gallery
Posts: 1,531
QuoteOriginally posted by Cerebum Quote
I, for my sins, expose to the left of my histogram. My process is to spot meter on what I perceive to be a mid tone, lock it in and recompose. My Exposure comp is generally around minus one (something I am going to try dropping from tomorrow). The purpose is to avoid blowing my highlights whilst protecting shadow detail but recently I have become increasingly dissatisfied with the exposure. So, seeking enlightenment I consulted the wise photo wizards in YouTubeland and came out even more confused. One said exposing to the right gives you smoother tonal transmission so we should always expose right! The next claimed better dynamic range can be achieved by exposing left. The third was more of a horses for courses type, suggesting left for high key scenes and right for low key (which kinda made sense, keeping away from the extremes) the question is does anyone have a magic formula? (Other than move somewhere sunny, which I have considered, Cádiz is rather splendid). The images here are always so beautifully exposed, I am hoping one of you will give up your secrets, it being Christmas and all that? ..... maybe?
It really depends on weather or not you are shooting raw or not

One has to understand that for a given output for the best exposure this can be different for raw and jpeg shooting. With in camera processing you really want to place your mid tones in their correct placement within the 8bit storage. With raw you have a lot more leeway in how you can process your image.

One of the first things you need to understand with raw is that every camera manufacture build in their own headroom and if you want to use the ETTR to the best of what the camera is able to store within the raw file you must override this headroom.
If we take a common image like this one

using the camera in processing or default raw conversion it looks something like this
But if we are to look at the data from the standpoint of what the cameras raw file has for storage it looks something like this

This is what it looks like based on the saturation capacity of the sensor, as you can see the image looks very dark and has a strange green color ( will discuses the green a little later). If we look at the raw file you can see that this image is underexposed from the standpoint of raw shooting. So we are able to shoot the image with a larger exposure thus giving us more DR and less noise in the final image.

Baseline exposure, is the setting that is recorded within the image file telling the raw converter where to correctly place the tonal curve to produce the jpeg file. If you are going to ETTR you need to understand how to override this in your raw converter
Deriving Hidden Baseline Exposure Compensation Applied by a Raw Converter | RawDigger

Here is one of the problems with try to shoot based on what the cameras raw file can store, All the tools we have from the camera manufacture like highlight blinkies and the histogram are based the jpeg image even when raw is selected
Any changes like WB to the jpeg image processing and the hidden headroom are shown in these tools. If you really want to understand what you need to understand the how in how images are being created
Here is a good start what is a raw histogram

Now to the green tint seen, How cameras produce an image have white balance applied to them and for most shooting conditions reds and blues are being underexposed and it is the green channel that is the one that is closest to clipping.

This creates a problem for you if you want to ETTR as the histogram on your camera is applying a multiplier to the red and blue channels to create a WB and this will not tell you how those channels are being filled and how they fall correctly in the raw file. Here comes UniWB
Introduction to UniWB
If a person what's to have a correct representation of what the raw file contains you have to understand how your camera works and what that data means to the raw file and how it is viewed in the histogram of the camera

How I use ETTR sometimes is that I manage it using a UniWB setting in the camera, setup a camera profile in the camera that undo's the highlight headroom, and using a UniWB and even with this its still does not give the user a good idea as to how the raw data is being stored.
My most used default is understanding how the camera spot meters and what that metering means to what is stored in the raw file, When ETTR I use a EV of +1.3 and spot meter on where I want white to fall within the image and have that spot metered point read +2 2/3

Some other good references
https://photographylife.com/where-are-my-mid-tones-baseline-exposure-compensation
Do Not Let White Balance Throw You Off-Balance | FastRawViewer
How to Use the Full Photographical Dynamic Range of Your Camera | FastRawViewer
The Optimum Digital Exposure - Luminous Landscape
12-25-2020, 09:10 PM   #11
Pentaxian
ecostigny's Avatar

Join Date: Nov 2017
Location: Branford, CT
Posts: 561
I've used ETTR for astrophotography, but I haven't tried it for more general photography. Something to think about.
12-25-2020, 10:47 PM   #12
Otis Memorial Pentaxian
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 42,007
QuoteOriginally posted by jatrax Quote
I think part of the confusion is different people using the same terminology but meaning different things.
Yep...many who claim to ETTL are actually exposing to the right and vice versa.


Steve
12-26-2020, 02:01 AM   #13
Site Supporter
Site Supporter




Join Date: Oct 2017
Location: Lancaster
Photos: Gallery
Posts: 3,829
Original Poster
QuoteOriginally posted by Ian Stuart Forsyth Quote
It really depends on weather or not you are shooting raw or not

One has to understand that for a given output for the best exposure this can be different for raw and jpeg shooting. With in camera processing you really want to place your mid tones in their correct placement within the 8bit storage. With raw you have a lot more leeway in how you can process your image.

One of the first things you need to understand with raw is that every camera manufacture build in their own headroom and if you want to use the ETTR to the best of what the camera is able to store within the raw file you must override this headroom.
If we take a common image like this one

using the camera in processing or default raw conversion it looks something like this
But if we are to look at the data from the standpoint of what the cameras raw file has for storage it looks something like this

This is what it looks like based on the saturation capacity of the sensor, as you can see the image looks very dark and has a strange green color ( will discuses the green a little later). If we look at the raw file you can see that this image is underexposed from the standpoint of raw shooting. So we are able to shoot the image with a larger exposure thus giving us more DR and less noise in the final image.

Baseline exposure, is the setting that is recorded within the image file telling the raw converter where to correctly place the tonal curve to produce the jpeg file. If you are going to ETTR you need to understand how to override this in your raw converter
Deriving Hidden Baseline Exposure Compensation Applied by a Raw Converter | RawDigger

Here is one of the problems with try to shoot based on what the cameras raw file can store, All the tools we have from the camera manufacture like highlight blinkies and the histogram are based the jpeg image even when raw is selected
Any changes like WB to the jpeg image processing and the hidden headroom are shown in these tools. If you really want to understand what you need to understand the how in how images are being created
Here is a good start what is a raw histogram
https://youtu.be/1K6gCpTgJVg

Now to the green tint seen, How cameras produce an image have white balance applied to them and for most shooting conditions reds and blues are being underexposed and it is the green channel that is the one that is closest to clipping.

This creates a problem for you if you want to ETTR as the histogram on your camera is applying a multiplier to the red and blue channels to create a WB and this will not tell you how those channels are being filled and how they fall correctly in the raw file. Here comes UniWB
Introduction to UniWB
If a person what's to have a correct representation of what the raw file contains you have to understand how your camera works and what that data means to the raw file and how it is viewed in the histogram of the camera

How I use ETTR sometimes is that I manage it using a UniWB setting in the camera, setup a camera profile in the camera that undo's the highlight headroom, and using a UniWB and even with this its still does not give the user a good idea as to how the raw data is being stored.
My most used default is understanding how the camera spot meters and what that metering means to what is stored in the raw file, When ETTR I use a EV of +1.3 and spot meter on where I want white to fall within the image and have that spot metered point read +2 2/3

Some other good references
https://photographylife.com/where-are-my-mid-tones-baseline-exposure-compensation
Do Not Let White Balance Throw You Off-Balance | FastRawViewer
How to Use the Full Photographical Dynamic Range of Your Camera | FastRawViewer
The Optimum Digital Exposure - Luminous Landscape
One lovely thing about Pentax Forums is that people take the time to write comprehensive replies. This is amongst the best. Thank you so much. I really appreciate it.
12-26-2020, 02:25 AM - 1 Like   #14
Pentaxian




Join Date: May 2009
Location: Somewhere over the rainbow
Photos: Gallery
Posts: 1,531
QuoteOriginally posted by Cerebum Quote
One lovely thing about Pentax Forums is that people take the time to write comprehensive replies. This is amongst the best. Thank you so much. I really appreciate it.
You also have to consider the output color space you are selecting and how you interpret the histogram


If we take this image and look at it from the standpoint that the red channels are at clipping then your normal assumption would be to lower or reduce your exposure to accommodate for what you perceive as overexposed. What would you say if I told you that this really doesn't tell you anything other than your color space in close to clipping

Here is the same colors but using another larger color space and looking at the histogram


So what did the first histogram tell you about how you should set your exposure?
The only difference is that the first was stored as a sRGB and the second Prohoto RGB
12-26-2020, 03:04 AM - 1 Like   #15
Pentaxian
Class A's Avatar

Join Date: Aug 2008
Location: Wellington, New Zealand
Posts: 11,251
QuoteOriginally posted by Cerebum Quote
The next claimed better dynamic range can be achieved by exposing left.
That does not make any sense.

ETTR is the best approach to exploit the full dynamic range of the sensor. Any lower exposure wastes some of the range.

QuoteOriginally posted by texandrews Quote
Here in Pentax land, the problem is further compounded by Pentax's penchant for seemingly hard cutoffs at the highlight end, but OTOH remarkable shadow recovery.
This statement may (I haven't checked it) make sense for JPEGs. It certainly does not make sense for RAW data. The latter has a linear correspondence to the light levels in the scene and there are no "shoulders" as we know them from film, neither in the highlights, nor in the shadows.

It is true that the Sony sensors used in Pentax cameras have very little digital noise, so shadow recovery is well-supported but that is true for practically every modern digital camera nowadays.

The JPEG engine within the camera may or may not have a harsher transition to clipping than other cameras, I really don't know, but I'd say anyone wondering about the level of improvement that ETTR provides over regular exposure, should definitely shoot RAW, instead of JPEG, and then forget about what the in-camera tone curves for JPEG development look like.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
canon, data, edge, ettr, exposure, image, lot, michael, noise, people, photography, thanks

Similar Threads
Thread Thread Starter Forum Replies Last Post
K-5 vs MZ-S vs LX vs PZ-1p vs ist*D vs K10D vs K20D vs K-7 vs....... Steelski Pentax K-5 & K-5 II 2 06-28-2017 04:59 PM
ISO Invariance ETTL indy Photographic Technique 14 03-30-2016 06:42 AM
Should Pentaxians use ETTR? y0chang Pentax DSLR Discussion 13 12-18-2014 01:55 AM
K10D and ETTR & High ISO Crosshair Pentax DSLR Discussion 2 02-22-2014 11:43 AM
Wireless ettl P12 Pentax Camera and Field Accessories 8 10-01-2011 04:10 AM



All times are GMT -7. The time now is 11:10 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top