Hi everyone, I'm reasonably new to DSLR photography, so apologies in advance if I use the wrong terminology.
A while ago I was looking through the viewfinder when I noticed a small mark near the corner of the image. I was terrified that I had got dirt on the sensor and would have to get it cleaned. Luckily, this mark did not appear on the subsequent images, leading me to believe it was just on the focus screen. I therefore decided not to interfere and ignore the mark, as it doesn't affect my photos.
However, another problem has arisen. I was taking some pictures of the horizon, and was very careful to make sure it was perfectly horizontal (obviously). Everything seemed level when I was using the viewfinder, but when I looked at the pictures on my computer (and on the camera screen), they were a little off-balance, by a degree or two. At first I thought my hand had slipped, so I tested it some more, and time and time again everything is "slanted" by a degree or two. I had to rotate all my pictures in photoshop and trim the edges, which was a pain.
Am I right in thinking that my focus screen is misaligned? If so, is it difficult (and expensive) to fix or replace? The mark I can ignore, the lack of balance I cannot.
I know I could just use the screen to take my photos (which doesn't result in slanted pictures), but I find that wastes the battery. I find it much more convenient to use the viewfinder, particularly on holiday when I'm taking a lot of photos all day.
Any diagnosis would be greatly appreciated.
To give you a really quick example, this skirting board looked perfectly level when I was using the focus screen/viewfinder:
#1. "RE: Nikon D5100 focus screen and viewfinder" In response to Reply # 0
Welcome to Nikonians! Are you using a hotshoe bubble level ? Have you tried using a different lens and if so, did the problem persist? If you are using a hotshoe bubble level and using another lens doesn't fix the problem, I would suspect the sensor is not aligned correctly. If you are determining level by looking through the viewfinder it is possible that the focusing screen retaining wire came loose. Here is a link to instructions for changing the focusing screen on your D5100: www.katzeyeoptics.com/files/install_13.pdf If the screen is loose you should be able to tell if you take off the lens and look closely at the finder screen at the bottom of the mirror box. Good Luck and Enjoy your Nikons!
#2. "RE: Nikon D5100 focus screen and viewfinder" In response to Reply # 0 Mon 17-Sep-12 11:53 PM by PRW
I don't know the cause of the problem, but what steps are you taking to ensure you have the camera level? Are you using a bubble level, or have you switched on the camera's virtual horizon feature, which will give you a line to check the composition?
Edit: I see Marty beat me to it with a much more comprehensive answer
Edit2: It seems the D5100 doesn't have the virtual horizon feature... Apologies!