Mixing Rodinal

[kenneth_amorino]

I have tried using Rodinal in two dillutions, 1:25 and 1:50, but the results

have been mixed on the half dozen or so rolls I have developed. I was wondering

if there was any special technique for mixing Rodinal. I noticed that there is

a strong spontaneous reaction when mixed with water and I was wondering if there

was any amount of time I needed to wait to use the developer? Thanks in advance.

[william_john_smith1]

I have been using Rodinal for almost forty years and all I do is dump the Rodinal into the

water and use it, never had a problem. Very easy to use, nothing to it.

[michaelging]

I never had a reaction like you described. I will say that if you get a syringe (with out the needle) and use that to measure the small quantities ,you will be more accurate,especially at 1 to 100 .

[ronald_moravec1]

There should be no strong reaction. Dump it in and strir 20 sec and it is ready to go. It

goes in dark and then the liquid turns to a tea color.

[frank.schifano]

What sort of reaction?

[Fotohuis RoVo]

In fact you must use diluted Rodinal in a short time. After stirring it's directy ready for use.

[gnashings]

I wonder if there may be an issue with water impurities, as I have never noticed any visible reaction. I mix in a mixing cup (from the baking supply section of the dollar store) and what I do is measure the Rodinal in a graduated cylinder, dump it into the cup and then add the water using the same graduated cylinder just to make sure that all the Rodinal got out and is mixed in. Never had a problem, and that makes me curious - what kind of reaction?

[andrew1]

Can you describe the reaction? I've used Rodinal for years, and never had any problems. One

suggestion I will make is that Rodinal seems to give nice results at higher dillutions- I use

1:50 and 1:100 regularly, and even 1:200 sometimes (in stand development). Negatives

seem to have a somehow more refined look the more dilute the Rodinal gets. Give it a shot.

[jtk]

If you mean the water looks like coffee, relax. That's to be expected.

[laurentvuillard]

Just a comment from a Rodianl user whose job is chemistry: Rodinal is very corrosive, wear specs while handling the concentrate it is badly alkaline . Iregularity is probably due to errors in dilution, also if there are large (>0,5cm 1/4 inch) crystals at bottom of your stock , it's no longer good.

[patrick_gainer]

Don't get too worried about the alkalinity. If you mix two very bad chemicals you may have a not-so-bad one at the end. Concentrated sulfuric acid and sodium hydroxide form sodium sulfate and water. What happens while they are mixing will not happen after they are mixed. Rodinal concentrate will not generate large amounts of heat while it is being diluted. It will make no difference whether one adds the stock to the water or the water to the stock.