overwashing fiber based silver gelatin prints

[jochem]

How long can I leave fiber based silver gelatin prints in the wash tray? Is there a danger of "overwashing" if left in water too long?

[SPPhoto]

Usually, the paper manufacturer will give their suggested wash times. If your talking an hour or two I don't think there would be any problems. If the prints aren't separated, and are just stacked on top off each other, I would try and rotate them a couple times. Your trying to purge all the bad chemicals out of the paper.

[sanchell]

SPPhoto is correct. For you to know, the problem with overwashing is not damage to the image per say, it is weakening the paper fibers. Although photo paper is tightly woven, any paper can break down if left in water too long. In my opinion, two hours is absolutely the limit, with one hour or less being preferable.



Do take note of SPPhotos warning, keep the papers seperated. If you don't have an archival washer, shuffle them no less than once every five minutes, and DO NOT overfill the tray. The more prints in the tray the more often you need to shuffle.



And finally never ever place the face of a print (silver side) against the back of a print. Always stack them in the tray back-to-back (non-silver paper base) and face to face (silver coated side to silver coated side). This is of extreme importance to proper washing.

[jbirdweb]

I agree with Steve, two hours max! I know when my wife and I had our custom lab I would often wash my fiber prints for an hour if I was going to tone them. My clients never had one complaint of any damage to the print.

[tim.bowman]

And finally never ever place the face of a print (silver side) against the back of a print. Always stack them in the tray back-to-back (non-silver paper base) and face to face (silver coated side to silver coated side). This is of extreme importance to proper washing.

I have seen this recommendation in multiple places. It does make sense intuitively and it's what I do with my prints.

But I've never seen an explanation of why to do this and what bad outcomes it avoids. Can anyone fill me in so I know why I'm doing the right thing?

[sanchell]

The reason for back-to-back and face-to-face is that the gelatin emulsion will adhere to the uncoated back of the print, and water will not be able to wash the chemistry from the back or front of the image.

The emulsion will not adhere to another emulsion while immersed. However, the emulsion will not separate from a back, even in running water.

The backs will also adhere to each other but will separate on their own in running water. If you are using standing water, manually separate the backs from each other when you shuffle, leaving a different print on top of the stack, back facing up, so that the back is also washed (you will want to rock the tray for this).

Always end your shuffling with the back side of the top print facing up and gently press the stack under the water's surface with the wide-spread palm of your hand (not fingers, as they might leave indents on some papers).

OOOPS! I WROTE THE NEXT PARAGRAPH WRONG! HERE IS THE CORRECTED VERSION. MEA CULPA

If you have an odd number of prints, always have the back of the odd print on top and the two lower prints back to back (the top print and second print should always be face-to-face).

If you have an even number of prints, have both the top and bottom prints with the backs facing out (top print, back up; bottom print, back down).

Always alternate which print is on top at the end of shuffling so that the back can be exposed to the wash water.

[tim.bowman]

Thank you, Steve. I figured it was either to ensure water circulation or to avoid scratches. Thank you for the detailed explanation!

[sanchell]

Please note that I miswrote one paragraph in the original version of the above. I have corrected it.