Lith developer agitation using an aquarium pump

[MarkL]

Back in 2009 the thread below talked about about circulating lith developer with an aquarium pump to tame Slavich Unibrom’s uneven development issues. The pump method should also be excellent for any other lith paper where development is an issue.

(there was a url link here which no longer exists)

Months ago, I emailed the two Russian photographers that Tim Rudman cited, via their websites. I asked them if they might share any ideas or pictures of their setups but neither one answered. They suggest they deliver the developer to the center of the print. My first thought is that there would be a lot more action there where the developer drops than there would be at the edges. So I'm thinking more of a whole-paper "shower". Crazy talk huh?!!!

Anyway, I'm undertaking to make such a setup and wonder if anyone has experience or suggestions, or is interested in my results.

Mark

 

[Rudeofus]

AFAIK lith developers are quite sensitive to oxidation, and showering may bring lots of air into the developer. YMMV

 

[MarkL]

Thanks Richard. I posted a reply in that thread, but then googled the device and found some pictures. I'm unsure how the print is held in place (would best be face up for watching the image develop). Any clips or weights to hold the paper down flat could well cause flow disruptions and over-development there. Do you have any more info?!

 

[MarkL]

Thanks Richard, for that detailed info. The device sounds like quite a large beast. Since the flow appears to be entirely under the print, evaluating progress, especially near snatch point, may be too cumbersome.

I've heard of a similar device for developing film but it's much simpler and could maybe be adapted to paper. It's basically a tray with a blocked off section at each end. Developer is pumped into one end, where it fills the compartment and overflows into the main mid section (which holds the emulsion-up film). The developer fills this compartment and then overflows into the compartment at the other end. This is where the developer is pumped around to the other end for another go-around. So the film (or paper) is held down under the fluid level and developer is constantly floating and moving over it with very little turbulance. This seems ideal to me except that the print will float and must be held down. Any clips or weights along the borders would presumably create turbulence and that is the problem we're trying to solve. Maybe a bit of a vacuum bed could be made. Or you could use wider borders on the print to keep the turbulence away from the image. Also, at the snatch point, the print would have to easy to release (be unclipped) in seconds. Or, the whole section holding down the print could be lifted out and placed in a tray of stop bath.

I know this all seems like overkill, but my motivation is that this Arthur Suilan (spelling?) claims to have absolute control and even development with difficult cold tone papers, specifically Slavich Unibrom, where random uncontrollable blacks can appear due to the agitation shortcomings of trays. I'm not sure how much I want to pursue the Unibrom look, but I certainly want to play with it. Also I have a large reserve of Emaks paper that has given me the same issues!

 

[Gerald C Koch]

Bubbling air through an easily oxidized solution like a developer is a very bad idea.

 

[MarkL]

Gerald, that may be. However, I'll quote text printed in the book The World of Lith Printing:

My solution was to develop emulsion in a thin moving layer of developer using an aquarium pump to continuously supply developer to the centre of print from the bottom of tray. Due to high productivity of pump (around 10 litres per minute) and water surface tension, developer forms thin even layer on the surface of print. Developer in this layer is quickly exchanged; fresh portions come to the centre and exhausted portions come off the print near the borders. Duration of contact with emulsion is around 1-2 sec. This method gives ABSOLUTELY even development to any lithable paper. Now I can completely control edges of cold-tone lith prints! Arthur Suilin Russia.

 

[Gerald C Koch]

Sorry it wasn't clear. Pumping air and pumping liquid are two different things. Now the worry is whether the developer will damage the pump.

 

[MarkL]

Ok...I've started building the contraption! Richard, Gerald and Rudeofus: thanks much for your interest.

 

[MarkL]

I wanted to report that I built my “lith shower” contraption, and have done substantial testing with 8x10 Slavich Unibrom grade 3. Of maybe 15 prints, I had no unwanted random infectious development anywhere on the print, and development seems to be perfectly even across the surface. I’ve ordered 11x14 to try next. If that develops well, I’ll move on to 16x20. There’s a chance that there will be development issues with the larger sizes, but I’m very happy about the results so far!

The test prints were so consistent that I was beginning to think that for this image and this developer, it might develop just fine with the usual method of tray development. So for an identically exposed 8x10, I used an 11x14 tray with fresh developer of the exact same quantity and ratio (no old brown) that I was using in the contraption. I rocked the tray gently but the very first print had the uneven development and random areas of dark overdevelopment that make Unibrom so hard to handle.

This setup was quite a bit of trouble to design and build, because I wanted it to handle up to 16x20 and wanted to accommodate a wide variety of solution quantities. I went to the trouble because I have a stock of discontinued Emaks paper that had the same finicky uncontrollable development in lith as Unibrom, and I burned through a lot of 16x20 trying unsuccessfully to make a certain image. So, I’m testing this method first with Slavich because it’s currently available (and is also a very cool paper in lith). Both papers can produce a lot of “artefacts” in lith, which may or may not be desirable depending on what you want. But at least there aren’t those nasty black overdeveloped areas anywhere, much less the edges!

I think another advantage of this system is that I believe it substantially speeds up long development times with very dilute developer. The many streams of developer impacting the surface seems much, much more dynamic than slow rocking of a tray. This would hold true for any paper, not just difficult papers. The disadvantage would be building and storing the thing, and also the increased oxidization of developer. A future improvement will be heating the developer. Currently it only circulates at ambient temperature.

If anyone is masochistic enough to want to build one of these, I would be willing to help you along. There are likely improvements to be made to this prototype, but so far, so good!

Mark

 

[MrBrowning]

I wanted to report that I built my “lith shower” contraption, and have done substantial testing with 8x10 Slavich Unibrom grade 3. Of maybe 15 prints, I had no unwanted random infectious development anywhere on the print, and development seems to be perfectly even across the surface. I’ve ordered 11x14 to try next. If that develops well, I’ll move on to 16x20. There’s a chance that there will be development issues with the larger sizes, but I’m very happy about the results so far!

The test prints were so consistent that I was beginning to think that for this image and this developer, it might develop just fine with the usual method of tray development. So for an identically exposed 8x10, I used an 11x14 tray with fresh developer of the exact same quantity and ratio (no old brown) that I was using in the contraption. I rocked the tray gently but the very first print had the uneven development and random areas of dark overdevelopment that make Unibrom so hard to handle.

This setup was quite a bit of trouble to design and build, because I wanted it to handle up to 16x20 and wanted to accommodate a wide variety of solution quantities. I went to the trouble because I have a stock of discontinued Emaks paper that had the same finicky uncontrollable development in lith as Unibrom, and I burned through a lot of 16x20 trying unsuccessfully to make a certain image. So, I’m testing this method first with Slavich because it’s currently available (and is also a very cool paper in lith). Both papers can produce a lot of “artefacts” in lith, which may or may not be desirable depending on what you want. But at least there aren’t those nasty black overdeveloped areas anywhere, much less the edges!

I think another advantage of this system is that I believe it substantially speeds up long development times with very dilute developer. The many streams of developer impacting the surface seems much, much more dynamic than slow rocking of a tray. This would hold true for any paper, not just difficult papers. The disadvantage would be building and storing the thing, and also the increased oxidization of developer. A future improvement will be heating the developer. Currently it only circulates at ambient temperature.

If anyone is masochistic enough to want to build one of these, I would be willing to help you along. There are likely improvements to be made to this prototype, but so far, so good!

Mark

Could you post a picture of your device? I'd be interested in trying something similar out.

 

[MarkL]