RO9 developer dilutions

[Steve M.]

I accidentally ordered a bottle of RO9 Spezial developer from Freestyle instead of the other developer that is supposed to be closer to Rodinal's original formula. The instructions on the side give times for a few different films at 1:15, but I wouldn't normally think to develop 35mm negs at that strength. Their developing times are pretty short too, w/ Tri-X shot at box speed noted to be at 3.5 to 5 minutes. My old protocol for this developer was 1:25 for everything, and it worked great.

Is the 1:15 dilution of this bottle of RO9 just a suggestion, and I need to do a few tests? Who shoots Tri-X at box speed anyway?

 

[Chriscrawfordphoto]

I'd try it at the dilution and time you normally use. It will probably be pretty close to correct. I have not used R09 Spezial, but I have used Adox R09, which is now discontinued, but it was also claimed to be be the original Rodinal formula, and it worked with normal Rodinal dilutions and times for me.

 

[Steve M.]

That's a good idea Chris. I'll do that, keep the agitations minimal and easy, see what happens.

 

[Steve M.]

Finally found the negs and a print from the Fomadon RO9 days. This is a print from a Retina w/ a Xenar lens using Tri-X w/ 1:25 dilution and minimum agitation for 7 minutes at 68 degrees.

Things get complicated real fast w/ this developer, because a grainy neg (like the one this wet print came from below) can still give an 8x10 wet print that is essentially grainless (see darkroom print below)! However, if you scan the neg, the grain will get bigger and appear quite prominently in a digital or inkjet print. This is a lousy print because I missed the focus on my scale focus Retina, but I kept it because the developer was so much sharper than my D76 negs.

 

[PRJ]

Go according to the instructions. R09 and R09 Spezial are different developers. DON'T use the same dilution/time you normally use for Rodinal. You will way over dilute the developer and might not get much of anything without an extended developing time.

From memory, R09 Spezial is a Hydroquinone/Phenidone developer. The only developing agent in Rodinal is P-Aminophenol. Totally different. Phenidone/Hyroquinone are super additive IIRC and they work together at a lower pH. P-Aminophenol relies on high pH to be active at the low dilution of Rodinal.

Hope that helps you.

 

[M.Hilo]

Go according to the instructions. R09 and R09 Spezial are different developers. DON'T use the same dilution/time you normally use for Rodinal. You will way over dilute the developer and might not get much of anything without an extended developing time. .

What I think!


Just buy the normal Rodinal equivalent you're used to and develop the way you're used to. You can use this spezial stuff for a special occasion.

 

[Pherdinand]

It's rodinal special, which has nothing to do with rodinal. Another name they used for it in agfa times was Studional.
1:15 is the regular dilution, can be reused a few times, and needs quite short dev times.
Results were for me finer grain than rodinal but less sharp.

 

[Bill Clark]

What works best for me with 35mm film 36 exposure is 6 ml of Rodinal to 600ml of water. Then stand develop for 60 minutes. Start with agitation then agitation at 30 minutes. I find this works for me no matter what film I used.