Dark Corner in Images - Minolta A1

I recently noticed that in the upper right hand corner of my pictures there is a blacked out area. It effects the upper most corner and the shape of this black out area is in the shape triangle with a curved bottom. The area affected by this blacked out area changes with zoom changes. This blacked out area is also visible on both the LED screen and eye view as well. Its size changes but it’s no larger the 1/2 to 1/4, but it is noticeable. I have attached two images that shows this problem, any thoughts as to what might be causing this? My question is have you seen this problem before and is it repairable? Any assistance in this matter would be greatly appreciated.

Sorry no images....

Are you using filters or something else in front on the lens...sounds like that is the problem.

Welcome to the forums!

Usually attributal to the lens hood, especially at wider angles.
What lens were you using? Did you have a lens hood on?
And I had a lot of trouble with this at all zooms with one lens until I figured out I had the lens hood on wrong, so good to check that.
If you can post your images, it would help.
They need to be resized to no more than 800 on a side.

Good Morning All, Thank you for your kind postings. I have attached a couple of photos that have been cut to show the dark corner. With that said, I'm not using any filter nor a hood, it's a most perplexing. At first I thought it might be vignetting, now I'm not sure because it's only the one corner and it changes size with distance. In some cases it almost disappears. Just for my own scientific process I snapped a photo of a whiteboard, here the issue can be clearly seen. Any help would be greatly appriciated. Thank you