snow,glaciers

[gracenrich]

Beginner going to Alaska for vacation.
What is a good setting for snow and glaciers?
Useing make that trying to use Nikon D80 18-200 lense

[ELAY]

Snow and ice can be surprisingly tricky.

For reasons that I could parrot but don't understand (something about metering for 18% gray), snow and ice pictures often come back underexposed (yes, underexposed) and grayish in colour. (My first day shooting the family ski trip this winter with my D40 was an exercise in hair-pulling frustration, as I could not figure out why everything looked so gray -- I figured it was the brightness of the snow that was a problem so I kept pushing my exposure compensation down, making the scenes more gray.)

This is why many cameras have a "snow" or "beach" setting (sand can have a similar problem). Solutions:

1. If your D80 has a snow or beach setting, try it.

2. Use your exposure compensation and dial in between +1 and +2 (use your LCD to fine-tune).

3. Set your exposure pointing at the sky, and use your exposure lock to lock this exposure for the shot (results can obviously vary depending on nature of light, what's in shadow, etc.).

White balance can sometimes be a problem too, with some cameras pushing toward blue in sunny conditions. The solution can be to set WB manually by shooting a patch of snow in the sun.

EL

[inkista]

...For reasons that I could parrot but don't understand (something about metering for 18% gray)...

Let me see if I can help. :) Back in the third grade or so, your math teacher taught you about averages. You add up all the values in a set, divide by the number of members in the set, and you get an average value--a single number to represent that set.

Automatic metering makes the assumption that your average value is also right in the middle of the tonal range ("18% gray" or middle-gray). So, exposure is set so that your average value will always come out as middle-gray.

This is great if you have even amounts of light and dark, and (if black is 0 and white is 1) your average is around .5.

The problem is that the assumption that your average value is in the middle of the range might be wrong. Say you're taking a shot at night. Auto metering averages out all those black pixels with the few white ones your average may be more like .2, and autoexposure tries to turn that near-black average value into middle gray. Result: overexposure. And you need to reduce exposure.

Say you're taking a shot of a snow scene. All those white pixels are averaged in, and a near-off-white (.8) then gets pulled down to middle gray. Result: underexposure. And you need to increase the exposure.

This is why we like having Manual mode and exposure compensation. :)

[ELAY]

Thanks for the explanation.

If I understand you, automatic exposure functions set aperture or shutter speed based on requirement that the resulting photo average 18% gray.

So if I am shooting a dazzling snowy photo, with lots of bright pixels, those bright pixels may be dragged down (made gray) by my automatic exposure to get to the average.

I'm guessing there must be some internal compensation process that moves the average around a bit, based on the relative areas of light and dark detected in the field of view -- or i would think that there would be a lot of shots needing exposure compensation. If not, wouldn't a black wall and a white wall shot in the same light end up being exposed the same?

EL

[subrataofkris]

Though I have never tried to photograph in the snow with my D50, I have done a lot of photo shoots in my old Pentax Film cameras for a decade. These are my observations:
Snow is a very high reflecting surface, where as a human character standing in the midst of snow is much darker. Moreover there is a huge amount of Ultra Violet light.

So if I have to shoot a human figure, I would go closure, take the exposure of the face/ clothes etc. and calculate an average exposure, then lock the exposure in my camera (only the exposure mind it). Then I would come back, compose, focus and shoot.

If I want the details of snow, I would get close to the snow, take reading of dark and light surface(shades) and lock the average calculated exposure. Then, as before, I would compose, focus and shoot.

If I need both the snow and characters (may not be human, may be a tent or boulder etc), I would have to choose between the two and make a tradeoff.

The above can be done manually also after noting the exposures.

To eliminate reflection in snow in the morning, I would use a circular polarizer and always have a UV filter on my lens otherwise.