O.K. Nikonians...REALLY dumb question: I was taking sunset pixes at our local inland sea, and they came out very well.
I was using My 3-stop graduated N.D. filter for the first time, and I covered the top 1/2 of the lens to hold back the sky.
When I reviewed the images, I remembered how the image looked on my view camera ground glass...upside down!
So, by placing the filter on the top part of the lens, was I holding back the wrong part of the photo? Next time, should I consider the inverted inmage, and put the darker portion of the filter over the bottom of the lens, or does the correct orientation of the image in the DSLR viewfinder show where the filter needs to go?
Can you post some images so we can see? Also, what camera where you shooting with? I have never used an grad filter but I didn't think it inverted the image. When you say "my view camera ground glass" are you talking about the viewfinder or LCD panel?
Nikonians is the Smithsonian of Nikon knowledge. If there is a question they can't answer, I want to see the question.
If you're wanting to darken the sky, you place the dark part of the grad filter at the top of the image, so you can follow your natural intuition. As JRP mentions, using the depth of field makes it easier to see where the gradation is in the image. It's typically easier with a hard-edged grad and/or with a wide-angle lens. On the other hand, a soft-edged grad is more forgiving of placement errors, so it's not too big of challenge using one.