Originally posted by Cerebum 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