Blown highlights - OK or not?

[mistermattias]

I've been out taking some photos in the snow in the northern parts of Sweden, but I just got blown highlights and as I try to adjust it in CS2 I just get more noise and it all looks weird.

I'd like to learn more about how to avoid blown highlights in the first place, but do I have to leave out the sky and add flash to get rid of it? Should I shoot in RAW and/or reframe instead and keep checking the histogram, or is there some good overall setting that can help me? Change the ISO? What to do when there are so many bright areas that I want to capture? Convert into B&W? Do you have any suggestions?

Here are some examples of what I saw out there. I'd like to be able to post even more http://www.pbase.com/mistermattias/snowy

[djwixx]

Blown highlights is over exposure, so there is effectively nothing to recover although it's surprising what RAW will allow you to pull out. Your suggestions won't prevent blown highlights, but you may want to get in the habit of reviewing the histogram to determine how well exposed you are and retake as required. If there is anything on the histogram touching the right hand side then you are overexposed. You can use the +/- button in all modes except auto to adjust the exposure compensation (+/-) to pull the histogram up or down to your preferred exposure. Depending on the lighting situation over or under exposure will need to be your choice if it's unavoidable. -0.7 may be a useful default exposure compensation setting but that will effectively mean you are underexposing which isn't always ideal. You can change your camera settings so you can meter using the AEL button to meter off the required part of the scene then use the shutter release simply to focus and release.

The article below is very useful on understanding histograms relative to exposure,
http://www.luminous-landscape.com/tutor ... rams.shtml

[themightyzog]

Hi, there is a Photoshop technique which will easily enhance (if that's the right word!) blown hilights.

I find it very useful when it happens and although it doesnt make a perfect print it is better than nought.

I've detailed it at the bottom of http://www.broadhurst-family.co.uk/left ... ctions.htm (under skin - but it works for any blown area) - hope that may help you

[marxz]

What is this "snow" stuff you talk about?


OK so snow is white? right? normally you'd expect snow shots to under expose (camera wants to expose to an average of 13% grey) so from what I recall from my (film based) photography studies you'd normally shoot at + EV settings (anything from +1 to +3 EV)

that said Digital is less forgiving of overexposures so that rule might be out the window

First off I'd probably want to shoot raw as raw gives about a 1 to 1.5 stop of highlight recovery.

Any suggestions beyond that I'll leave to those who have actually seen snow first hand.

[madlights]

Snow is really hard to shoot...like Mattias says. The meter wants to see a medium grey so you've got to exposure compensate 1.5 to 2 stops (anyway) brighter to get the snow white. I think this is what Mattias means (and please correct me if I'm wrong Mattias?), because when you do that it's hard to keep from blowing out the highs. If you underexpose (or even close to correctly expose) according to the meter (histogram) to maintain highlights you introduce noise when you bring it back up to get true white, and get weird blue color casts sometimes (from the reflected sky especially in the shadows and because of the original darkness the shadows when brought up seem more saturated too, usually blue). The contrasts are usually very great too. Black trees against really bright snow etc. I know I've put way more Photoshop work into some snow shots than summer landscapes...trying to get the color casts and noise out. I've tried polarizers, and sometimes they work a bit to tame down the cumulus clouds when exposure compensated +2. but then on wide angle shots (28mm eqiv and below) even at 90 deg. to the light path, sometimes the sky wil be of a very disturbing un-uniform color that's nearly impossible to correct. I know what Mattias means. Guess there's always a tripod and HDR techniques, but it's not fun to carry any more than you have to when plodding around in drifts...and don't know if HDR would help much with the blue color casts (and yeah they are technically correct I 'spose as the camera sees them, but most people want white snow to see. I've had people say "how come the snow looks blue?" I've actually had better luck on grey days when the sky and snow aren't far apart in values and the blue from the sky doesn't have such an effect. It's all a real problem as far as I've experienced too.
Edit: Oh yeah and that's a beautiful gallery Mattias, one of the nicer snow galleries I've seen...the blue looks right in place in your shots that have it. I always have trouble with getting the snow white and only the shadows blue...especially on bright blue days.

[dougj]

The camera will generally meter for 18% grey for the area selected for metering. So if the camera only 'sees' snow for its evaluation, it will be grey in the image. Should the camera see a wider dynamic range within the shot, it will adjust accordingly.

The evaluation and settings the camera chooses depend on what you have programmed and selected it to read. Spot metering will differ significantly from evaluative or the other metering modes.

Shots with snow that include dark/shadow areas are challenging as the dynamic range (DR) is large, frequently exceeding the sensor DR abilities. Within the dynamic range of your camera you need to decide what you want – blown highlights and reasonable shadow detail; or highlights within range and low shadow/dark detail. The latter is OK if you shoot at low ISO and have limited shadow noise to deal with post processing.

Alternatively you can do 2-3 shots and merge them via a high dynamic range (HDR) program. RAW is also an alternative as it gains ~ 1 stop in DR. RAW is nice as it is very easy to correct for ‘blue snow’ by adjusting the shot color temperature in post processing.

I looked at a few of your shots, and they are good. I didn’t see severe problems with the over exposed areas; you could probably improve these with ‘Shadows & Highlights’ in Photoshop.

IMHO, there is nothing wrong with having some areas of a photo overexposed in some shots anyway. What do you want the viewer to see in your photo? A small bit of over exposed snow might add to the image….

[azleader]

The previous suggestions, especially exposure compensation and dynamic range considerations, are all good. Snow is a difficult subject to photograph.

A simple solution to try is use a feathered brush of low opacity (around 10% to start) to lightly clone in detail from closely matched areas of the image that are better exposed. It is remarkably easy and applied gingerly will look 100% natural and not cloned at all.

[djwixx]

The section below on the "Sky Brothers" in the book Understanding Exposure by Bryan Peterson has some great tips on light metering including snow. The previous sections include the Gray Card and 18% Reflectance. Worth a read.

http://books.google.com/books?id=v4lw2l ... #PPA122,M1

[gymell]

I took a quick look, didn't notice any obvious blown highlights. It would be helpful if you could point to a specific photo where you believe this is a problem.

Snow itself doesn't result in blown highlights, but several of the scenes you shot look like they have a pretty wide range of light. It does look like you used some HDR on some of the photos, which is what you'd have to do to to avoid overexposure, or underexposure, in a scene where the range of light is greater than the camera can handle in a single exposure.

I find shooting in snow actually one of the easiest ways to meter. I shoot RAW and manual, and using spot metering I point at some snow and overexpose one stop. Assuming the snow is in the same light as my subject, then that's all I need to do. I shoot a lot of eagles in the winter, and that technique works quite well.