Do I lose any image quality from the JPEG files on my memory cards when using Nikon's image viewing software or something like Digital Imaging Suite from IXLA. Both provide thumbnail views of images. Will my repeated use of these thumbnail images affect the quality of the image stored on the card?

Thanks

-- Frank Herzog (Fherzog@mindspring.com), May 27, 2000

Answers

Frank:
It depends on what you mean by "use". If you are explicitly saving the thumbnails over the the existing JPG images then you are significantly reducing image quality. However
...if you are only looking at the images then you may do so a gazillion times without fear of degrading the quality. Unless you are saving images back to the card (can you even do that?) then you are doing to harm.

In general there seems to be a lot of confusion around viewing compressed images. Let me state clearly that viewing any image - compressed or not - results in absolutely no degredation of the image file. Viewing and saving does re-compress the image and does degrade it.

Des

-- Dan Desjardins (dan.desjardins@avstarnews.com), May 27, 2000.

I meant to say "...you are doing no harm."

Des

-- Dan Desjardins (dan.desjardins@avstarnews.com), May 27, 2000.

So if you shoot something in portrait, load it into a viewer, flip it 90 degrees and save it for slideshow viewing, you lose something? Better to flip it and save the landscape image as a "b" version keeping the original for printing?

-- bill (this_old_house@pobox.com), May 28, 2000.

yeah you lose something. Normally, resaving jpegs you lose something, however, there are special (free?) programs that will rotate your images without losing anything.

-- benoit (foo@bar.com), June 01, 2000.