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H. G. Hart
22-Mar-2004, 22:45
I have several questions regarding the use of Rodinal to develop sheet film when using either a Jobo rotary processor or BTZS tubes. I shoot 4x5 black and white landscapes; I typically enlarge to 16x20 or 24x30.

First, because these methods use constant agitation, what dilution is best to use? If, as I assume, a higher dilution of Rodinal is preferable, do I have to worry about the developer exhausting since the Jobo drums and BTZS tube in particular have limited capacities?

I have heard that the addition of sodium sulfite to Rodinal helps to soften the grain, which might be desirable for 24x30 prints. I would prefer not to make any noticeable sacrifices in sharpness however. Any advice?

I currently plan to use Ilford FP4+ or possibly FP5+. I have used these films in 35mm in the past and enjoyed them. Until recently I have been using Fortepan 200 film in 4x5 with D-76 1:1.

Thanks in advance

jose angel
23-Mar-2004, 04:19
I want to tell you that Rodinal is my favourite developer. Grain is high with this developer, but I love the acutance provided and tonality.

I use it in my CPE-2 with the 2800 drums. I started with the 4+196cc (something equal to 1+50) dilution, but turned to 3+297cc (= 1+100 dilution) that I find more confortable to use, itīs my actually working dilution. Probably 2+198cc could work also, but I didnīt test it. I want the most simple and accurate process, itīs not worth to me to mix or add chemicals to the stock solution. For a smaller grain I would use D76 or Xtol.

In my tests (120 roll film), I find a very different look between several films when developed in Rodinal. Iīm using it with APX400, that gives a very different look (the most beutiful) than the others I tasted before like HP5+ (more "conventional"), BRF200 (beautiful and really grainy), TX and TMY.

My enlargements from 6x6 (Mamiya6) films are not bigger than 16x16", and in this size the grain start to be clearly noticeable, but still acceptable. I wonder if using the 4x5" format the grain could be the same in a 24x30" print. With FP4 grain must be much smaller.

Sorry, in the 4x5" format Iīm still using D-76 1+1 (that as you know give a much smaller grain). My intention is to change also to a different developer when received a new stock of sheet film. I understand that Rodinal will work in the same way with the sheet film. Good luck,

jose angel
23-Mar-2004, 04:54
I donīt I have my notes here, but I remember that when I did my tests, I was looking for differences in grain, film speed and curves with different dilutions (1+25, 1+50 and 1+100).

Diferences were so dim; in the graphics the curves (slopes?) are practically the same with the three dilutions. Simply, you need more developing time to obtain the desired density when solutions are more diluted. I try to remember that film foot speed are moreless the same in all the dilutions I tried, 200 ASA for the APX400 120, 160 in the HP5+ 120. I didīt find a compensating effect at 1+100. Grain looks with a higher edge cutted effect when using a more diluted solution in the APX400. I decided to use it at 3+297cc., comfortable to me with 16 min. at 20šC for a N developing time in the Jobo. Probably it will work perfectly at much more diluted solutions.

karl french
23-Mar-2004, 06:27
The Jobo USA website recommends the 1:25 dilution. They felt that it gave better results than 1:50. I have used 1:25 with APX100 with very nice results, although the negatives didn't look that different from those developed in other non-staining developers. Based on my reading, I think a lot of the special properties of Rodinal are lost with constant agitation. In order to get the edge effects/acutance that rodinal is known for limited agitation is required.

good luck

karl

David Beal
23-Mar-2004, 13:42
I have used Rodinal in homemade BTZS tubes for old Tri-X, Fuji Acros, and Efke PL100. I shoot the Efke at 80, the Acros at 80, and the Tri-X at 250. Processing requires 100 cc of solution. For Efke and Akros, I use 1:50 for 10 minutes at 68 degrees with continuous agitation. For old Tri-X, I use 1:100 at 68 degrees for 20 minutes with continuous agitation.

Although you CAN use Rodinal for Delta 100, I do not, as I prefer DD-X for that film.

Darin Cozine
25-Mar-2004, 08:59
HG, I've used Ilford fp4 @ iso 125, developed in Rodinol 1:50 for 15 minutes. This was rotary processed. I was very pleased with the results, but I am no expert.

The normal processing time is 18 minutes. Ilford reccomends 'as much as' 15% reduction in processing times for continuous agitation, but I am finding that 15-25% reduction is more accurate.