Discussion in 'Photography Beginners' Forum' started by six-five-two, Sep 22, 2007.
I heard there is some problem with the pictures ending up 18% grey/gray? How do I fix that problem?
Exposure compensation. Try this by taking a photo of a white ceiling. You'll find that the white comes up no where near white.
Nearly all cameras have exposure compensation which basically just forces the camera to select the settings for an exposure value above or below what the camera would pick. Try +1EV as a start and work from there.
I thought that snow was grey.
Does your camera have exposure lock? I usually set the exposure using something darker than the snow, such as the palm of my hand, or the blue of the sky. Just use something that you want represented as a midtone. This is an alternative to using exposure compensation. For example, for this picture I set the exposure using the sky to the right of the frame:
So I am up in the mountains. I aim my camera at the blue sky or at my palm, and hold my shutter button halfway. I also press AE-L (that means Exposure Lock right?). I then aim my camera to a white mountain and take a picture. Is that what you're trying to say?
Or you could purchase a grey card and hold it in front of the camera before you shoot... but it all comes out to about the same.
Yes, if that is how the exposure lock works on your camera. What camera do you have? The idea is to judge what would be a midtone. If you use the palm of your hand, hold it in full sun. Using the sky means that you don't have to take your gloves off, if you are wearing them.
93rdcurrent, or I can just go to a painting shop and get some grey paint sample card things, right?
Helen, Pentax K100D.
Yep... Now you're gettin' the idea.
Now I get how to do it, but how does this work? How exactly is pointing a camera at a grey card or at the sky or at your palm, locking the exposure then aiming at snow make the snow white and not grey?
They way I understand it the the sensors in digital cameras are extremely sensitive to bright light sources. The cameras processor tries to dim the whites to compensate for it. I could be wrong but that seems like what I've read somewhere.
Overexpose by two stops, as a start point, 3-4 on really bright sunny days. The cameras meter is just being fooled by all that white. H
Your camera (every camera) knows only to measure how an 18% grey surface should look. In other words, you point it at the snow(bright white) but the camera thinks you're pointing it at a grey surface that is only THAT white and shiny because it's under crazy lighting. Hence, it tries to underplay the lighting in order for the bright white to come out as grey.
Everything is just a shade of grey to a camera. If you point it at a black surface, it thinks it sees 18% grey in darkness, and if you point it at pure white, it thinks it's looking at 18% grey in bright light. In the former, you would want to underexpose. In the latter, you would want to overexpose.
Think about it, it makes sense.
Separate names with a comma.