rodinal agitation

I noticed that the data sheet that came with my latest Rodinal purchase has a

different agitation recommendation then previous sheets. The new

recommendation is for continuous agitation for the first 30 seconds and then 5

seconds every 30 seconds thereafter. I have always agitated Rodinal for 10

seconds on the minute throughout the development. Does anyone have an idea how

these two different recommendations will effect the resulting negative? I

develop Plus X with the 1:50 dilution and have always been happy with the

agitation on the minute approach.

I noticed that too. I wouldn't change what is working for you. It's hard enough to get to a point where you are satisfied.

10/60 will give slightly less contrast than 5/30. To make them the same, add 10 % to the 10/60 time.

 

The old pattern worked with older thick emulsion films.

Less agitation will increase contrast and adjaceny effects. Depending on developer, it could also increase grain somewhat.

 

5/30 is pretty much standard, but some folks prefer 10/60. I've tried both but use the former. Bottom line: pick one and stick with it! The key to success is consistency.

"Bottom line: pick one and stick with it! The key to success is consistency."

 

That's always been my philosophy as well. Remember the Rodinal hasn't changed, just the data sheet.

I continue to give 6 inversions in the first 30 seconds with one inversion every 30 seconds thereafter. Just before each inversion I give the tank a swift half-turn as it stands on the bench to impart some circular motion to the developer.

I've seen that it doesn't make a big difference one way or the other. Any slight differences in contrast caused by the differing agitation schemes can easily be swamped by other factors. To really assess the differences you'll need to keep all the variables, film, camera, exposure settings, lighting, etc., constant. If what you're already doing is working for you, then keep on doing it. If you want to run the experiment, be sure to control all your variables to achieve meaningful data points.

"Less agitation will increase contrast and adjaceny effects. Depending on developer, it could also increase grain somewhat"

 

Really? I have always found that increase in agitation gave more contrast, and the low agitation yielded the opposite effect. Hmmm.

What data sheet? The last bottle I bought (a&o) only had the hazardous chemical labeling.

If you want to see some dramatic differences try experimenting with continuous agitation. Despite the name, it doesn't need to be truly continuous. One inversion every 5 seconds is fine.

 

You'll need to use a much shorter development time with continuous agitation. It's been years since I tried this technique and the last couple of times I tried it was with Neofin Blue. But the results can be interesting if you're in the mood to research the appropriate times for given films and experiment with a few rolls.

 

Otherwise, the differences between agitation at 30 second and 60 second intervals are usually minimal.

Frank Schifano is right the difference in agitation pattern is minimal so I bet it'll; be hard to see any objetcive difference, the key issue is to move the dev around the film so it does not become exhausted next to very dark regions of the image, once shaken five or ten sec is will not matter, continuous agitation will matter.