Rondinal 1+25, 1+50 or 1+100?

[ruicardoso]

Hello All,

 

I've been using Rondinal mostly with Agfa APX 100 and Pan F. At this

point I'm not able to do my own printing, so I've been scanning film

and using a photo printer.

 

My doubt is: in theory what should I expect when using different

dilutions of Rondinal in terms of grain and tonal scale? Can I

easyally see those differences in the film itself, or will they only

show up in printing?

 

In the scans I do and for APX 100 I see no diference between the

films paroccessed at 1+25 and 1+50. And I can not find anything in

the Agfa site.

 

I usualy process Pan F at 1+50, just because I find the sugested

time for 1+25 too short.

 

Thanks All!

 

-Rui

[frank.schifano]

You pose an interesting question. I've no experience with the Agfa APX films, but I have done more than a few rolls of Pan F+ in Rodinal at 1:50. At dilutions of 1:100, Rodinal will cost you a full stop of speed and with a film this slow, I find that unacceptable. Rodinal is not a speed enhancing, nor even a speed maintaining developer at this dilution ratio. Generally speaking, you should get a bit less contrast with higher dilutions of the developer. You might be able to tell the difference if you did a side by side comparison of two negatives of the same subject in the same light if all the other variables are identical except for your development. Grain structure in Pan F+ is so fine in any case that you probably won't see any practical effect until you make enlargements of 8x or greater. I can easily get grainless 11x14 prints from 6x6 cm. Pan F+ negatives developed in Rodinal at 1:50.

 

I'm assuming that you are using a film scanner. It's been my experience that these machines are really optimized for use with C-41 films. I have an HP Photosmart, which is not a top of the line machine by any means, but it does reasonably well with color negatives, less good with E6 films, and is absolutely awful with conventional B&W materials. One of my friends has a top Canon scanner and another a top Nikon scanner and both perform better than mine does, but both do not do nearly as well with conventional B&W materials than they do with C-41 or E6 materials. The point of all this preliminary verbiage is that you probably won't see much difference in your scans unless the differences in your negatives are far from subtle. Printing your negatives on conventional B&W material will no doubt show more of the subtle differences between your negatives and will be far superior to anything you'll get from a desktop inkjet printer.

[bryan_weiss]

Rodinal at 1:100 using Efke films acts as a compensating developer and gives a great tone to the film. I have no experience using the APX 100 but I do not find a speed loss with the Efke films as long as sufficient solution is used. For example, in a 2 reel tank I use only one reel but still fill up the tank.

[jimvanson]

Rodinal *Will Not* cost all films a stop when used in high dilutions. I shoot APX 100 @ 100 and process in Rodinal @ 1+100 for 20-22 minutes @ 68 degrees...Wonderful Stuff! TriX is rated @ 400 in 1+100 Rodinal where as HP5+ must be rated at 160. Here is Agfa's pdf on dilute Rodinal and <a href="http://unblinkingeye.com/Articles/Times/times.html">Ed Buffaloe's</a> great site where numerous uses for Rodinal are posted.

[jimvanson]

Rodinal *Will Not* cost *All* films a stop when used in high dilutions. I shoot APX 100 @ 100 and process in Rodinal @ 1+100 for 20-22 minutes @ 68 degrees...Wonderful Stuff! TriX is rated @ 400 in 1+100 Rodinal where as HP5+ must be rated at 160. Here is Agfa's pdf on dilute Rodinal and <a href="http://unblinkingeye.com/Articles/Times/times.html">Ed Buffaloe's</a> great site where numerous uses for Rodinal are posted.

[frank.schifano]

I was referring specifically to Rodinal at 1:100 for Pan F+. In that case you do lose a stop.

[ruicardoso]

Hello All,

 

Thanks for your answers!... But i still have my main doubt: "in theory what should I expect when using different dilutions of Rondinal in terms of grain and tonal scale?" ... Can I assume that I'll allways have less contrast?... And what about grain?

 

Thanks,

 

-Rui

[m0002a]

The phrase �tonal scale� is highly subjective, and should probably be analyzed in terms of contrast, sharpness, etc.

 

Higher dilutions of Rodinal will almost always result in less contrast, although the differences can be neutralized if too vigorous of an agitation is used. Whether you can always see the difference in contrast between the various dilutions may be debatable.

 

In relation to grain, one theory is that higher dilutions reduce the alkalinity of Rodinal (which is more alkaline that most other developers) and therefore reduces swelling of the emulsion. Emulsion swelling is believed to be related to grain clumping, which is perceived as increased grain (see �The Film Developing Cookbook,� Anchell and Troop, page 4, left margin). Most people (although not all) believe that higher dilutions of Rodinal also improves sharpness and �edge effects.�

 

This is the opposite of most other developers, which contain fairly high levels of sodium sulfite (unlike Rodinal). Sodium sulfite reduces apparent grain (or keeps it in check) and when a developer that contains it is diluted, apparent grain is increased (but sharpness is also increased).