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View Full Version : Integrity Of Jpeg Files



mongo
21-08-2009, 12:56pm
Mongo understands that every time you “save” a jpeg file it loses some integrity.

You usually “save” after doing some work or changes to the file.

BUT – what Mongo wants to know specifically is do you lose some integrity every time you open and simply close a jpeg file to look at it (i.e without doing any changes to it)????

DAdeGroot
21-08-2009, 1:02pm
BUT – what Mongo wants to know specifically is do you lose some integrity every time you open and simply close a jpeg file to look at it (i.e without doing any changes to it)????

No, not unless you viewing program auto-saves for reasons unknown.

Whisky_Mac
21-08-2009, 1:44pm
DAdeGroot is right. Opening and closing with out saving a jpg will not alter it, but if you were to close it by hitting the save as button and overwrite it it will degrade.

I have three folders for the images, folder one is the original camera raw files, folder two has the tiff files which are saved LZW compression which is a lossless compression and folder three has the jpg's save at 12, which is the least amount of compression but still will degrade the image. Saving at high compression (1 or 2) my give you a small file but will encourage jpg artefacts.

If I want to adjust the image I will use the tiff image or all the way back to the original camera file and overwrite the jpg's.

That is the reason I only shoot in raw, there are times when you think just use jpg only or shoot raw and JPG but it is really not any quick and you compromise yourself with the computer processing.

Maybe I am mad and create more work for myself. As Ned said "such is life"

mongo
21-08-2009, 2:00pm
Thanks Guys -that Is Pretty Clear And Good Advice.

ving
21-08-2009, 2:05pm
yup, as stated :)