JPEG storage of Resized Files

[Ken Katz]

For printing 18" x 12" images (from a D60), I generally resize the

file to 300 DPI and resharpen. Assuming I have no intention of

doing further manipulation with such a file, and will just use it

for printing additional copies, will the prints be impacted if I

save the file as a JPEG instead of keeping it as a TIFF (in order to

save some disk space)?

[emre]

The prints won't be affected, but you might be sorry if you want to convert the files to another file format in ten years.

[vipros]

If you keep the compression ratio lower in JPEG, you won't feel sorry in ten years :)

 

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<a href=http://www.vipros.com/photo> My Photo Gallery </a>

[emre]

Given the favorable rate at which storage space is becoming cheaper compared with the rate at which digital files are growing, I think it makes more sense just to keep files as they are.

 

Have you tried using JPEG2000 lossless? You will get much smaller files than with an uncompressed TIFF. It might be good enough for you.

[dan_n1]

I would suggest that you keep

 

- 1 copy of the RAW files (assuming that you shoot RAW)

 

- 1 copy of PSD (or TIFF) files with layers

 

- 1 copy of final JPG. These jpg will stay as is as long as you won't open

them, make changes and re-save as JPEG.

 

This seems a bit too much but it will serve as backup and you still can go back

to the originals if there will be any changes in technologies in the future...

[jtk]

What's the point of keeping JPEGs if you've got TIFFs?

[dan_n1]

well... for myself, I keep JPG for multiple requests of the same size, same

resolution of an image or same ptints request later on. I even keep a version

of lo-res (save for web) to send via email to whoever want to preview the

images.....

[lex_jenkins]

You might try the other JPEG variations, such as JPEG 2000 (already mentioned) or LuraWave. These are reportedly lossless or nearly so. They are not universally recognized by web browsers and file viewers so you should consider these storage formats. The files may need to be converted before use if you decided to work on them later.

 

PNG is a fairly common format and much more compact than TIFFs. I've tried it several times and in comparisons of the same images magnified several times I see no significant differences in details or image integrity.