Why I Purposely Underexpose All My Raw Images

Why I Purposely Underexpose All My Raw Images

By now it’s common knowledge that when shooting film, it’s important to not underexpose to hold on to shadows, and for digital it’s key to save the highlights. I’m going to advocate, however, that with modern digital sensors, it’s prudent to shoot underexposed all the time.

You’ll hear many people argue that there are certain situations where underexposing has its benefits, but not all the time. While it may sound counter-intuitive to the folks arguing to “get it right in the camera” all the time, there’s a method to my madness.

The first major reason to underexpose is to get a faster shutter speed. Sports photographers know that if they’re in a tough environment (for instance, a night college soccer game) then underexposing will give them the precious extra stop or two of shutter speed. The difference between 1/250 and 1/500 could mean the difference between getting a blurry mess or a sharp shot. The penalty comes on the back end, where you have to process that photo out so that it’s properly exposed, but with modern software, batch processing a large amount of files to the same exposure isn’t challenging.

But beyond the faster shutter speeds that are possible, there’s the practical benefit of protecting the highlights. Even dialing in a third of a stop or two thirds can give you the leeway to prevent a sky from blowing out, or a white shirt from blending into a white background.

I first started doing this mostly by accident more than a decade ago, when screens on digital cameras were so poor that I thought I was overexposing all of the time when I set the meter to 0. Instead, I found that things looked just fine on the computer, and I was just being fooled by chimping on the camera. But I still gained that exposure latitude, and the practice just stuck.

The original file in its underexposed state. It was easy to bring it back to proper exposure in Photoshop.

The original file from above in its underexposed state, shot this way to get a faster shutter speed of 1/500. It was easy to bring it back to proper exposure in Photoshop.

Of course this only applies for raw files. If you’re shooting JPG, you don’t have the editing headroom. Don’t do it!

What do you think? Is underexposing all of the time crazy? Do you do it too? Leave your thoughts in the comments below.

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89 Comments

I do same at times, especially when shooting with flash so as to compensate. Getting it too low risk messing up the picture as usual

Will Gavillan's picture

I too, do this all the time. My main reason is to preserve highlights when using flash, which is the majority of the time.

Stas Aleksandersson's picture

My wheel is on EV -0.7 all the time.

JetCity Ninja's picture

same here. i'm usually on a tripod shooting landscapes but i generally expose -2/3 to -1 EV in daylight. i'm going to post process all of my images anyways, so bumping up the exposure a stop in post is nothing and worth protecting the highlights. digital *generally* preserves shadows better than highlights at base ISO, so the benefits of the headroom outweighs any potential drawbacks.

Benoit Pigeon's picture

It all depends on end use. Are they going to be printed large? I personally wouldn't but I understand what you are doing.
There are times to do it and times not. Wouldn't you want to up the ISO one stop as well? You'll have noise to fix both way.
Processing should never be an issue and NEVER WAS. We did that with film, digital is the same way. Processing shy is wrong in my opinion. There is capture and processing and I believe that people who avoid the processing part are not getting the full understanding of what photography is.
Getting it right in camera has no meaning. Getting it right in camera with the intention ahead of processing for a specific need has value. And that is what you do when you decide ahead on how you will process the images. We used to pull and push chromes with the same intention and alter very slightly the first bath for the same reason. I've seen it done on 8x10 film. NEVER listen to others if your process works fine for your need especially after 10 years of practice.

Rob Davis's picture

I know I do this is in high contrast situations. Some people have said different raw files respond differently when I’ve said this. I do this with Nikon raw, but some Canon folks have cautioned against this. Maybe that’s changed now though.

Jared Wolfe's picture

From what I have seen, Canon and Sony have a lot more wiggle room in highlights, where as nikon blows highlights really easily - but handles shadow recovery really well. As a canon shooter I shoot to the right much more aggressively than I think would be wise for Nikon shooters.

Canon tends to underexpose by roughly a third of a stop compared to Nikon and without EC one is generally better exposing to the right to capture the most information though there are times for bracketing and situations to do what the author describes. The more difficult question is balancing the optimal Tv, ISO, DR, etc. against noise, motion artifact, etc. in real time.

Tim Gallo's picture

In my experience Canon looses details shadows very easily... also some contrasty lens they have, so its better to overexpose just a little bit to get details in shadows. Highlights is not a problem with 1 or 2 stops this days. But I just finished teaching my assistant retouching who uses Canon we compared few shots in studio in same conditions with Nikon, and again Canon looked like it looses shadows details almost immediately if underexposed, Nikon has no such problems. but than again there is a factor of lenses... so the general advice is to get the exposure right. Over-exposing or under-exposing is a myth for some reason persistent in the internet...

Wasim Ahmad's picture

I found this to be true for previous generations of Canons, but 5D4/1DX2 and newer seem to hold the shadows much better than they did in the past, at least for me.

When I shot d800 years ago I would crank up shutter speed in exteme low-light situations to capture action and was able to crank up the exposure back in Lightroom or Capture One due to the dynamic range of that sensor. I preferred to have an "underexposed" image than to have a properly exposed image that has way too much motion blur due to low shutter speed.

I haven't used Lightroom since about 2012 but back then I felt LR did a better job than C1 in bringing back images that were pretty underexposed this way.

Dani Diamond had a post about underexposing for portraits.

Dave Terry's picture

I have been doing this for about 6 years as well. Originally, it was mostly to just get faster shutter speeds when shooting bands that play in very low light at local bars. In those low-light conditions, ninety percent of the time my aperture is always wide open (f/1.4-2.8 depending on lens), shutter at a minimum of 1/200th, and ISO adjusted to whatever I need to make up the difference… but it’s almost always 1 to 2 stops under-exposed so I can keep my ISO lower as well.

Of course it’s possible to underexpose too much, but within reason, as long as you don’t try and dig too deeply, the details you dig out of the shadows in post will look great. If you’re not afraid to let your darkest shadows to go black - and you shouldn’t be - you may begin to see more film-like textures to your photos without trying to manufacture that look in post. Different cameras and different megapixel counts vary in look, so you have to find out what setting combos look best with your specific camera.

I grew up appreciating and EXPECTING to see grain in low light concert photos shot on film. Some of the most iconic photos are super-grainy compared to today’s standards. Don’t be afraid of grain! Be afraid of bad-looking grain. Not all grain is created equally. The grain produced naturally by modern-sensors is very film-like, but over-exposing makes it look trashy.

Learning nuance in your exposure/post-processing settings can help get a more aesthetically pleasing result in your final images.

Same here. My Fuji deals with shadows really well but highlights easily blow out.

I agree. Underexposing gives much more leeway in post processing of the RAW images. Would much rather be under rather than over-exposed. Ideally, perfect in-camera exposure would be ideal, but good luck getting that every time. -2/3 to -1 usually does a nice job.

Mihael Tominšek's picture

This is camera relative. Some cameras lie in positive some in negative EV. Histogram is made from JPEG!! 1st use RawDigger to examine exactly where your camera/meter clips. I found on my Pentax K5ii than I am losing 2 f-stops of DR just because jpeg profiles were made bright. I tunes one jpeg profile to push development exposure down, so it matches raw when I open files. I can use spot meter on brightest sky, dial +3 EV compensation, lock exposure and everything will be just perfect from ETTR stand point, so I maximize DR. That way I can push ISO at least one f-stop further to previous. Previously images were noisy just because they were underexposed by 2-fstops even than where was plenty of light. Now I know. For night event photography, where spot light are concerned, there is mostly so great DR it will never do anything than silhouettes if spot light is exposed. It is trade off. So I make test shot than decide. I leave 1/2 f-stop lower than maximum, to be safe.

Some cameras are very prone to processing noise. Canon. But Sony sensor cameras are OK. You will not harm image by underexposing. Still I rather bump ISO. It is always more beneficial. At least I can review photos better at he back of the camera.

I always try to get as much light as possible while still freezing as much action as I need to, while not clipping highlights. So yes, sometimes increase the speed while ISO and aperture remain the same and then bring it up in post; helps that my sensor is ISO invariant for the most part. But other times it's not action I want, but DOF and a smaller aperture, so same thing. But as a default I'll make it bright right up to the limit, even if the JPEG in the window looks hideous, so that I maximize the amount of light info I'm gathering.

B Moore's picture

I spot meter off the important highlights and add + 3EV of EC https://www.fastrawviewer.com/blog/spot-meter-exposure

I went to the comment sections to see if there was at least one person to use the proper technique. THANKS!
I learned this recently and I am still 'experiencing' but it funny how much I was taught wrong by internet.

Black Z Eddie .'s picture

Yep, I'm typically underexposed to perverse...err.. preserve the highlights on the sky, but most importantly on the skin. I try to keep the histogram slightly stretched to about -2/3 stop. Varies depends on how harsh the sun is.

Simon Patterson's picture

Interesting to see that just about everybody else in the comments does this, too. Add me to the list!

Simon Patterson's picture

Interesting to see that just about everybody else in the comments does this, too. Add me to the list!

Edmund Devereaux's picture

I just recently started that myself. Especially as most images are seen on a bright screen so it always looks better.

Yes, the difference between self-illumination and other-illumination, the difference between a back-lig self-glowing display presentation, and a front-lit reflective print presentation.
.

First off relating shutter speed as a reason to under expose is fine if you need too. However it compromises your image.

“Always” is the key point. Obviously the contrast, color latitude, their relationship to how the image is exposed is lost in this post.

You don’t need to under expose to hold highlights. You do need to properly expose however.
If you want to loose information in the blacks for an artistic purpose go for it.

Agreed, if your shooting on auto for sports it’s a good protective technique. But for others exposure is and has been one of the fundamental crafts of photography since film.

It’s almost as ridiculous as mis-spelling the word ridiculous.

And I think you are blowing your response way out of proportion. Under exposing a shot slightly (in relation to the cameras light meter) as many others are saying allows you to protect highlights, shadows can be lifted far easier than highlights recovered.

I shoot a lot at sunset, if I ‘correctly’ expose my shot as per the meter the sky will be blown out so I notch it down to compensate.

Thank you for correcting my spelling, it was late. However adjusting exposure also effects the
contrast and color latitude. I don't mean to be in a contest here. When I used to shoot 16mm I would rate the film 1/4 lower. The Kodak iso (asa) gave us very little room for error. So what the article is saying is that you have a little more room for error. However, if you are in a controlled environment its always best to define your look. I only have an issue with the "always" part.

The spelling correction was a more a joke than being a pedant tbh.

Yes it’s not ‘always’ the correct thing to do but I assume the author is working on the assumption that the majority of photographers are working contrasty environments 99% of the time, which is kind of true (at least from what I’ve seen).

The only true way of retaining details in both without noise/blowouts is to use filters or bracket, otherwise it’s a case of exposing for the highlights (which often reads as under on the meter) then dealing with shadows in post, which I think is the original point.

I usually shoot with my exposure comp at -.5 or -1. I wouldn't call this underexposing, but preserving highlights. It seems cameras like to overexpose.

Too many do not understand what is going on here. Several things they do not understand.

First, this is nothing more than push-processing. This has the same advantages and disadvantages as it had in the film days, (and done for the same reasons).

Second, “grain” is a direct result of not saturating the film, be it emulsion or silicon. It is not really “grain,” which truly did exist with emulsion, but photon noise, which is independent of the film, and only dependent on the amount of light hitting any given part of the film, due to the Poisson distribution.

In a properly exposed scene, there is “grain” —more properly, noise— in the shadows. As the scene is underexposed, more noise appears in the shadows, and some start to show in the mid-tones. As the underexposure increases, the noise in the shadow and mid-tones increase, and start the appear in the highlights.

This is true whether the underexposure is as a result of setting the exposure index to any ISO value above the base sensitivity,† setting the exposure compensation to a negative value, or simply adjusting the exposure time lower, or the f-number higher.

Third, preserving the highlight is not as important as preserving the detail where one wants detail. That is the basic difference between high-key, (expose for Shadow detail), and low-key, (expose for highlight detail), photography. Sometimes one needs to let the highlights get blown-out, and sometimes one needs to let the shadows get crushed.

†If you think raising your EI in camera does not produce more noise, it is because your camera is doing high-ISO noise reduction. This comes at a price; less detail.

John Koster's picture

Sounds good in theory. With modern sensors (sensors produced in the past five years) you have several stops you can pull up your shadows and not worry about detail loss. Doesn't matter if it's better sensors, processors or algorithms, you've got plenty to play with.

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