The fastest and smoothest image viewer I've used is jpegview. There is also a fork. - Source: Reddit / 7 days ago
JPEGView is your go-to. Not only is it incredibly lightweight (even portable), but it allows you to almost instantly view an image in full resolution, switch to next or previous images within the same folder, quickly zoom in with scroll or fit to screen with space, and has a built in editor for adjusting contrast, brightness, hue etc.. - Source: Reddit / 12 days ago
Jpegview is the best at handling large files that I've tried. - Source: Reddit / 14 days ago
Try https://sourceforge.net/projects/jpegview/. - Source: Reddit / 3 months ago
Do you know an article comparing JPEGView to other products?
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