Re: [PRODIG] PS7 .jpeg resave

[Robert McClory]

Martin Evening wrote:

OK, try this test. Take an image save it as a JPEG using a low-medium setting. Copy this first version and keep it located in a separate folder. Now reopen and record an action that resaves the first image using the same JPEG setting and closes the file. Keep reopening and applying the action - say, ten times or so. Now open the first version drag the 10x resaved JPEG image as a new, registered layer (hold down the shift key as you drag one window the other with the move tool) and then set the new layer to difference mode.

In difference mode, any differences between one layer and the other will show up as image detail. If the difference is slight, you may have to add a major levels or curves adjustment layer to the top of the layer stack. Do the results surprise you?

Martin and List Members,

First of all, I'm sorry for the email address inclusion. I will delete email addresses from replies in the future per list requirements. Secondly, I did not intend for this to become a discussion of the perils of resaving .jpg files. If you look at my previous posts, I specify a maximum quality resave of a .jpg. It is only a one time resave at the max setting I am talking about. If I am concerned about quality at all, which is most of the time, I resave as .tiff or shoot RAW in the camera. I am aware that a multiple resave at med/low quality (as per your suggested test) will cause a significant reduction in image integrity, so the results of the test were not surprising.
It seems as if the answer to this question I'm getting here is sounding a lot like the old proverb about a man going to the doctor complaining about how his arm hurts when he bends it. The doctor of course replies "Well, then don't bend your arm."
I appreciate all of your concerns about the quality of my images, and always welcome any help anyone has to offer that will make my photography better. I am always trying to learn, and judging from the quality of the work produced by most list members, I am in a very good place to do that.
That being said, I would appreciate anyone that could give any insight to my original post about a corruption that occurs when resaving a .jpg from a Nikon D1X to .jpg out of Photoshop 7.0. If you have specific info about this problem that could be included along with admonishments about the hazards of resaving in the .jpg format I would be eternally grateful.

From the responses I've received thus far it seems like I may be the only

one on the list who's tried to resave an image like this, so maybe someone with a D1X could try it and post their results, good, bad or otherwise.

Thank you,
Robert McClory



_________________________________________________________________
The new MSN 8: smart spam protection and 2 months FREE* http://join.msn.com/?page=features/junkmail

===============================================================
GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE