white snow without blowing out

Elaine

Hmm...not sure this should go here or in Technique...:scratch

I've had the chance to take some snow pics this week, and the next two weeks I'll be in Alaska and so will have lots of chances for snow pics! I am very conscious of underexposed snow pics and for the most part, I think I've got that figured out. A few I've processed this week do not have any areas equaling 255, 255, 255, but some spots come close and some areas are bright enough that they appear blown out, even though they aren't. Is that the nature of a properly exposed pic in the snow? How does one retain snow detail without making it look like concrete?

Here are some examples:

1 - The roof and the street are so blank. I'm not sure what else it should look like...I do want the snow to be white, just not blown.


2 - This one has a tiny vignette which greyed some of the snow at the bottom.


3 - There is detail to be had in the snow on the ground, but you can only see a tiny bit of it. Is this also due to the overcast/soft lighting? Or did I get this one too bright to begin with?


Any tips or pointers for snow shooting? Thanks!

LivingLarge

Your exposure is spot on. I think alot of what you seem to be fighting here is overcast skies. There has to be "some" directional light inorder to show the definition in the snow, ie: cast a shadow. Since your shots are during snowfall, chances are you have a pretty overcast day.

jfriend

There are two separate issues you are asking about.

The first is getting the exposure so that you don't blow the detail in the snow. If you have extremely uniform light like you do in these heavily overcast shots, then you can probably just flip the camera to manual mode, dial in an appropriate exposure, check a couple of test shots on the histogram to make sure you aren't under or over exposing and then shoot away. What's important is that you are actually capturing the highest tones. In a heavily overcast situation, your dynamic range shouldn't be too high so you should be able to capture all detail.

The second issue is how to get the detail in the snow to actually show. To do that you need contrast. When you have extremely flat lighting, there is so little tonal difference in the texture of the snow that it's hard to see the detail that is there. Side lighting is the best for providing detail because it makes shadows on the snow and emphasizes the texture and terrain of the snow. In post processing, the only thing I've found I can do is to create some sort of mask for the snow areas and steepen a curve a lot in the highlight area. I generally have to do it with some sort of mask or blend-if control because otherwise, the curve pulls the mid-tones down way more than I want. While keeping the brightest part of the snow near a tonal value of 250, when you create good contrast, you will be pulling other parts of the snow down into the mid-tone range. By necessity, this will make some of the snow "more gray". I know of no way to get the contrast to see the detail without this.

Here's how a quick run on one of your images comes out.



Compared to your original:

Elaine

OK, I feel better! I figured the overcast skies were part of the issue. I do shoot manually 99% of the time and always watch my histogram and expose up to the right. So, it seems I'm doing the basics correctly, and in these overcast circumstances, bringing out snow detail comes down to post. Thank you for sharing that example. That really helped bring out the snow detail! Which wouldn't have been there if I had blown it originally, so I think I'm on the right track.

arodney

Elaine wrote:

OK, I feel better! I figured the overcast skies were part of the issue. I do shoot manually 99% of the time and always watch my histogram and expose up to the right.

You shooting Raw and exposing for Raw or, JPEG (in which case, the camera histogram is providing the final clipping info)?


http://www.digitalphotopro.com/technique/camera-technique/exposing-for-raw.html

Elaine

arodney wrote:

You shooting Raw and exposing for Raw or, JPEG (in which case, the camera histogram is providing the final clipping info)?


http://www.digitalphotopro.com/technique/camera-technique/exposing-for-raw.html

I am shooting Raw. The whole thing about the histogram showing JPEG results has always confused me a bit. I'll check out your article.

arodney

Elaine wrote:

I am shooting Raw. The whole thing about the histogram showing JPEG results has always confused me a bit. I'll check out your article.

The Histogram on the camera is based on the in camera JPEG which of course, you're not shooting. Its a big fat lie.

jfriend

arodney wrote:

The Histogram on the camera is based on the in camera JPEG which of course, you're not shooting. Its a big fat lie.

Andrew, when shooting RAW, how do you recommend one check for blown highlights on a test shot? I read your article and it did a fine job at explaining why the JPEG preview is a poor indication of what's in the RAW data (which I already understood to be the case, but I appreciate seeing your test data), but it didn't seem to answer the question for what to do instead? Do you have an opinion on the use of UniWB?

The other issue that would be nice to see in your article is that once you've raised your ISO above the base, you will achieve minimum noise when getting as much exposure (shutter speed and aperture) as you can without blowing highlights. If one compares two exposures of:

ISO 800, 1/80, f/2.8
vs.
ISO 1600, 1/125, f/2.8

the second will appear to be more ETTR on the histogram, but it actually captured fewer photons (faster shutter speed) so it probably has a worse signal to noise ratio and thus more visible noise.

arodney

jfriend wrote:

Andrew, when shooting RAW, how do you recommend one check for blown highlights on a test shot?

First off, you need to know the actual ISO sensitively of the chip for Raw.

You can try to extrapolate this reality to the big lie on the LCD, not too easy. It would be ideal if the camera manufacturers would show us the true Raw clipping. But the bottom line is, IF you're shooting Raw AND you are viewing the Histogram, you can be a good stop and half over exposed as defined by this Histogram and not have actually clipped the Raw data.

Of course, if you're shooting tethered, or have the time to control the image, you can bracket or view the Raw histogram in a good converter and lock this down. Again, not easy.

arodney

jfriend wrote:

The other issue that would be nice to see in your article is that once you've raised your ISO above the base, you will achieve minimum noise when getting as much exposure (shutter speed and aperture) as you can without blowing highlights. If one compares two exposures of:

ISO 800, 1/80, f/2.8
vs.
ISO 1600, 1/125, f/2.8

the second will appear to be more ETTR on the histogram, but it actually captured fewer photons (faster shutter speed) so it probably has a worse signal to noise ratio and thus more visible noise.

The best setting for optimal quality is the lowest ISO with proper exposure for Raw.

We don't live in a perfect world. I shoot at highest ISO all the time in natural light settings. I get noise. The alternative is to get an image that's blurred (due to low a shutter), or totally lacks data I can render into something I can upload as a web gallery or print.

Just got my new 5D Mark II today. I'm excited about the very high ISO settings for available light shooting with (usually) my fastest lens, a 35mm F1.4. Its going to be noisy. But I'm shooting in dimly lit rooms and at this point, I simply want a capture. But ideal in terms of data and quality, its not. I can't light the scene (on camera flash don't cut it, I'd rather have natural light with noise). That's where Noiseware comes into play.

Expose to the Right is useful to understand when you have control over the light or enough light to expose to get optimal data. But its quite often we don't have such a luxury.

Going back to the snow question, I would assume in the shots seen, there was plenty of light to shoot at a low ISO and move the data such that there's little or no noise in the shadows and plenty of data in that all important, first stop of highlight data.

gmitchel850

arodney wrote:

That's where Noiseware comes into play.

I wrote a comprehensive review of Noiseware. It's a 26 page .PDF document (almost 5MB).

http://www.thelightsright.com/Noiseware4

I also updated my review of Nik Dfine 2.

http://www.thelightsright.com/NikDfine2

Comprehensive reviews of Neat Image, Noise Ninja, Topaz, AKVIS Noise Buster, and Power Retouch are coming soon. Plus a comprehensive comparison of them all as a group.

Cheers,

Mitch