BIG Enlarged Negatives?

[maxbloom]

So let's say I have a large contact-printing paper, say Azo in 20x24 or perhaps in the future the Lodima in that size. But all I've got to work with is a 4X5 neg. I've got some experience making enlarged negatives onto 8x10 Kodalith, but that's about it, and all that's readily available in 20x24 is APHS unless I want to enlarge onto pan film. What limitations and considerations are there in making an enlarged negative of this size?

Thanks.

 

[keithwms]

Besides the APHS route you mention, you could have an LVT made. But 16x20 may be the limit, I guess. You may find other suitable options at hybridphoto.

Anyway, for enlarging this much, I think the main issue is getting your enlarger well aligned and finding a lens with suitable coverage... basically the same issues you have with enlarging to paper except the exposure and developing conditions require more diligence.

 

[maxbloom]

A 20x24 enlargement onto paper isn't that big of a stretch from 4x5, is all I mean. Is there something about enlarging onto film that size that changes things?

AFAIK LVT only goes up to 8x10.

 

[keithwms]

Well, optically, no it's not so different from enlarging to paper. But the things is, if you make an interpositive and then a copy neg using ortho film, then you have dueling contrast ranges. You might need to develop the interpositive with a developer of one contrast and then develop the copy neg with another... so there are coupled variables to tune and that's what makes it inherently trickier than a straight enlargement to paper.

About LVTs, I know that Chicago Albumen does them to 16x20, but "only" at 1016 ppi.

 

[maxbloom]

I may give the APHS/Pyro protocol from View Camera (republished on UnblinkingEye) a try. Does anyone have any experience with that particular workflow, or perhaps an alternate one with good results for huge enlargements?

http://unblinkingeye.com/Articles/EnlargeNeg/enlargeneg.html


Oh, and why not use an ortho film for the interpos?

 

[bdial]

Is there something about enlarging onto film that size that changes things?

No, not really, film is probably a little better at preserving sharpness than paper. But that's only relevant if you're comparing two first generation positives, one on paper and one on film.

OTH, if you're looking to make a contact print then you must print onto film twice and likely lose tonality each time. I can't think of any advantage of doing that way vs. just making a silver 20x24 projection print.

 

[keithwms]

Max, did you consider dr5 processing? Then you could go straight to ortho and have a dupe negative.

There's nothing terribly hard about working through two ortho developments, at least you can develop by inspection. But when I played wth this a bit (using ilford o+ and ID11), I came to the conclusion that some contrast adjustments are probably necessary at both steps to get the best results, because you have an inherent contrast mismatch right off the bat. In my case, the neg I was enlarging was a very contrasty IR neg and it basically didn't matter so much, but if the starting neg has more tonal subtlety.. then it's just going to take time/effort.

 

[maxbloom]

Well I'm just thinking about the future. My current Azo is old 10x10 double weight. When/if Lodima is released, there's nothing btw 11x14 and 20x24, and I'll loose a little tonality and sharpness the larger I go.

 

[maxbloom]

Max, did you consider dr5 processing? Then you could go straight to ortho and have a dupe negative.

Well I'm sure dr5 to ortho would be better than neg to so-134 or something, but I'm not familiar enough with dr5 to understand its development's impacts on my originals. This is already an uncertain process to me.

It seems that it would make more sense to contact print my original negative onto ortho, which, because of its smaller size, I can experiment with more and have more easily predictable results when making the enlargement. That's opposed, of course, to contact printing from my original to something like tmax (which my original would not be) and then onto a third, different film. Seems it would be better to have two of the three films in the process (the interpos and the enlarged) be the same.

 

[keithwms]

This is just an idea: go ahead and enlarge directly to large ortho, and also make a few exposures at the same enlargement factor onto a few smaller pieces of ortho film. Then send the whole lot to dr5. Tell them to develop the small pieces first, pay them a bit extra to check the densities at that stage and then process the large piece accordingly.

Mind you, I have no idea if this arrangement is practical for you or them...

 

[maxbloom]

dr5's site says they only develop up to 8x10...so that's out.

I think i'll just stick to the neg-->contact ortho-->enlarged ortho and see how it works out.

 

[rcoda]

I just had some enlarged negs made by Chicago Albumen Works... they turned out great.

If you will just be contact printing the 1016 or even 508 dpi will be good enough. (better than inkjet negs FOR SURE).

 

[dancqu]

I've got some experience making enlarged
negatives onto 8x10 Kodalith, ... Thanks.

Are you thinking direct negatives such as by the
method detailed at unblinkingeye? For small and
large sheet process/litho shop Valley Litho. Dan