Stretched paper? - Ilford 16x20 Multigrade FB not dimensionally stable?

[MattKing]

The sources of paper available to Harman and others are significantly different than what they once were. And many of the changes in the industry are relatively recent.
I'm sorry that you have encountered an unexpected ramification of that.
That being said, is a thin over-mat a possible solution?

 

[Pieter12]

An Xacto knife and a metal straight edge will make everything fine.

 

[koraks]

I think what I'm finding is that the prints swell. and are larger when they are processed.

I'm sorry, I misread your first post and now notice that the sheets are larger when they're still wet. That makes a lot more sense. What size do they end up being when they've dried again? What size differences do you note when dried taped to a sheet of glass vs. air-dried and then flattened?
As @Lachlan Young points out it is inherent to the manufacturing process that the paper will shrink (and sometimes warp!) at different rates along both dimensions. In e.g. full-color gump printing, this is a problem, since registration of the multiple color layers will be difficult (impossible) to get exactly right through subsequent wet/dry processing steps. Gum printing is of course different from silver gelatin in that it generally starts with a different kind of paper than silver gelatin (although I guess it's possible to gum print onto fixed out silver gel. paper as well). Still, the paper base as such is conceptually comparable. Calvin Grier suggests for gum printing to pre-shrink the paper by soaking and drying it a couple of times, and during processing, hang it up to dry always in the same orientation.

This method of pre-shrinking is evidently not attractive (or perhaps even feasible) with silver gelatin paper. However, I can imagine that it's possible to make a 'calibration sheet' that you print two sets of rulers onto, then process and dry it and observe the final dimensions of the image after the paper is fully dry and flattened. You can then use this final dimension to approximate an overall shrink/expansion ratio, and apply it to your production work. It'll never be perfectly consistent, but it may be good enough for your purposes. I'd suggest giving this a try. Otherwise, I think the only real option left is to let go of the requirement of trying to 'print into' an existing matte and find another way to present your images while making use of the existing frames.

Respectfully Lachlan

From a moderator's perspective: we're all trying to help, and I frankly don't read @Lachlan Young's posts as patronizing or otherwise insulting. I feel he's (admittedly somewhat assertively) expressing the inherent difficulty of what you're trying to do.

 

[Ian C]

I believe that I had something like that happen to a 50-sheet box of Ilford MGIV FB Warmtone paper some years ago. I printed a negative of a scene involving many tall, straight trees. After fixing and turning on the lights, it was obvious that the trunks of the trees showed significant barrel distortion. Those near the center looked straight. But those farther from the center showed a great deal of curvature. Those on the ends showed the worst barrel curvature.

This was done with a Mamiya RZ67 and a 110 mm f/2.8 lens. The enlarger lens was a 4/80 Rodagon. These have always given good results. When I reprinted onto some 8” x 10” paper of the same type a few minutes later, the result was perfect. The problem was the paper stock. It had nothing to do with the coatings.

I discussed this with Ron Mowry (“Photoengineer”). He said that the problem was known as “calendaring,” He explained how it came about during the manufacture of the paper stock. He suggested that I contact Ilford to both inform it of the problem and to obtain a replacement (which, unfortunately, I didn’t do). The distortion remained after the print was fully dried. As Ron explained it to me, the wet paper expanded along the long dimension, but not along the short dimension during processing. The change was permanent.

 

[Carnie Bob]

We just finished a job using Ilford fb paper, 40 inch x 26.5 inches, we sized the print to 40.2inches x 26.625 inches to allow for shrinkage, the final print is 40 inches x 26.5 inches;
this issues as Drew points out apparent with any paper when soaked, therefore for all my gum over prints on paper are pre shrunk, also a little known effect
is that inkjet prints will shrink , specifically the really long print with lots of ink on the image.... We are very aware of the George Constana problem.

 

[koraks]

He said that the problem was known as “calendaring,”

Calendering is the process of hard-pressing the paper. This may or may not have effects on shrinkage (I don't expect it'll be much really.) The main cause of uneven shrinkage is the web weave itself as indicated earlier by @Lachlan Young .

Those on the ends showed the worst barrel curvature.

Were the masked edges of the print also warped?

We are very aware of the George Constana problem.

LOL!

 

[Lachlan Young]

In e.g. full-color gump printing, this is a problem, since registration of the multiple color layers will be difficult (impossible) to get exactly right through subsequent wet/dry processing steps. Gum printing is of course different from silver gelatin in that it generally starts with a different kind of paper than silver gelatin

There's a very strong case that any multiple wet-dry process involving registered images should be done on as rigid a substrate as possible - e.g. dry-mounted to aluminium offset plates which are very thin, but capable of easily being register punched.

Avedon's (and his assistants') methods of dry mounting large silver gel prints to aluminium before fitting them to acrylic vitrines is well documented too.

If I'm a bit irked by the whole thing it's that plenty of us have to fit prints to pre-existing frames of a variety of sizes on a routine basis - a bit of common sense would have meant acknowledging the propensity of paper substrates to subtly change shape when going through wet/ dry steps, making sure the print sheet size was oversize, then trimming to fit - rather than people proclaiming that it absolutely must be a manufacturing fault instead of very evident end-user oversights.

 

[retina_restoration]

plenty of us have to fit prints to pre-existing frames of a variety of sizes on a routine basis - a bit of common sense would have meant acknowledging the propensity of paper substrates to subtly change shape when going through wet/ dry steps, making sure the print sheet size was oversize, then trimming to fit - rather than people proclaiming that it absolutely must be a manufacturing fault instead of very evident end-user oversights.

I'm inclined to agree. If you know there's a specific issue with how your materials behave, then find a workaround and apply it to your methods. It seems to me that expecting your materials to behave in ways that they clearly do not is only going to be a persistent irritant without a solution.

 

[grain elevator]

I haven't tried the taping-to-glass method, so I don't know if this is totally ludicrous. But I'm interested, as I can foresee needing flatter prints and owning a dry-mounting press, especially one for large prints, seems utopian. Might it be worth a try to only tape along the short edges or would it warp too much? That would leave the paper a bit more free to contract along the dimension that otherwise remains stretched.

 

[koraks]

Might it be worth a try to only tape along the short edges or would it warp too much?

Yep, you'll end up with a print that's wider on the taped edges and narrower in the middle. It's also irreversible. I've had prints where one or two taped sides came loose during drying. It's very...interesting.

 

[MTGseattle]

This is all news to me as well, but I admit to never using anything other than screens and time to dry fiber-based prints.

I'm curious regarding the drying time for a wet print placed on a substrate to help with flatness.

Before I built my drying rack, I used piles of books and clean mat board sheets to "press" my prints flat. I can see where space/time may not be available for such methods.

 

[DREW WILEY]

Maybe a short course on basic DIY papermaking would make the principle quite apparent.

 

[Ardpatrick]

I'm sorry, I misread your first post and now notice that the sheets are larger when they're still wet. That makes a lot more sense. What size do they end up being when they've dried again? What size differences do you note when dried taped to a sheet of glass vs. air-dried and then flattened?
As @Lachlan Young points out it is inherent to the manufacturing process that the paper will shrink (and sometimes warp!) at different rates along both dimensions. In e.g. full-color gump printing, this is a problem, since registration of the multiple color layers will be difficult (impossible) to get exactly right through subsequent wet/dry processing steps. Gum printing is of course different from silver gelatin in that it generally starts with a different kind of paper than silver gelatin (although I guess it's possible to gum print onto fixed out silver gel. paper as well). Still, the paper base as such is conceptually comparable. Calvin Grier suggests for gum printing to pre-shrink the paper by soaking and drying it a couple of times, and during processing, hang it up to dry always in the same orientation.

This method of pre-shrinking is evidently not attractive (or perhaps even feasible) with silver gelatin paper. However, I can imagine that it's possible to make a 'calibration sheet' that you print two sets of rulers onto, then process and dry it and observe the final dimensions of the image after the paper is fully dry and flattened. You can then use this final dimension to approximate an overall shrink/expansion ratio, and apply it to your production work. It'll never be perfectly consistent, but it may be good enough for your purposes. I'd suggest giving this a try. Otherwise, I think the only real option left is to let go of the requirement of trying to 'print into' an existing matte and find another way to present your images while making use of the existing frames.


From a moderator's perspective: we're all trying to help, and I frankly don't read @Lachlan Young's posts as patronizing or otherwise insulting. I feel he's (admittedly somewhat assertively) expressing the inherent difficulty of what you're trying to do.

What I'm finding is that air dried prints come in at 19 7/8 x 16 inches dry. Taped on glass prints come in at 19 7/8 x 16 3/8 inches. None of this is a major issue for the majority of imagery / mounting techniques which is good news, as edges are either masked or cropped. I'm doing something particular, which is why it jumped out at me as a notable surprise.

Going forward I've already thought about the idea of reverse engineering a process using a known, established calibration sheet as you term it - something of known size like a sheet of film! Wait for it, someone is going to now tell me how naive I am to assume any two pieces of film can be relied upon to be the specified size!