How do I save one of my photos and make it my wallpaper/background for my 27inch imac. When I use one of my photos the picture is blurry and pixelated. Also where do I save the photo to, if this might make a difference
its all dependent on the resolution of the original photo.
you can set any photo you want as wallpaper, then go to system preferences, then Desktop/ScreenSaver pane and select near the top where it says Fill Screen, Fit TO Screen, Tile, etc thats where you can adjust the resolution of that photo to fit according to the size of it without it pixelating much or at all.
Here's the thing. If you took the photo using say 4K by 3000 you should be good. Always go high as possible in image sizes, especially if you want to print em.
You can check the dimensions of a photo in Aperture and possibly iPhoto. Or just check on your camera.
How do I save one of my photos and make it my wallpaper/background for my 27inch imac. When I use one of my photos the picture is blurry and pixelated. Also where do I save the photo to, if this might make a difference
You should use a photo with equal to, or higher than the resolution of the screen (i.e. 2560 x 1440). You should also use one with the same dimensions as the resolution, otherwise you will have to crop or stretch.
If your images are from your camera, make sure its set to full resolution. Also you can crop to the right dimensions.