While loading an image, the UI uses a blown-up thumbnail as a placeholder... option to change this?

Looking at the blown-up thumbnails while waiting for the full-size images to load is pretty uncomfortable for my eyes... they search for detail that isn't there yet, and get strained. If there was an option to just see a spinning wheel or similar, I'd choose it in a heartbeat. Alternatively, displaying the image line by line as it loads (slow scan from top to bottom) would be even better, as it would allow me back out before loading the whole thing.