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cosmicexplosion
30-Jul-2012, 19:08
4 gallons or 15 liters
That's my tank size
I'm using 1/100 so ten mills per litre
Last night I did ten sheets no probs
But I have the feeling I could do a lot more
How many do you think is a safe figure?
Cheers
Andrew the good.

Leigh
31-Jul-2012, 05:52
You need 10 ml of Rodinal concentrate per 8x10 sheet of film.
That's published in the Rodinal instruction sheet.
The dilution used and the capacity of the tank are totally irrelevant.

For example, if you're developing 15 sheets in a tank, you need 150 ml of Rodinal concentrate.
At 1:50 you would have ~7500 ml of dilute developer, which would only half fill your 4 gallon tank.
You could add more water to get up to 15000 ml to fill the tank, but that would be a 1:100 dilution.

If you really want a 1:50 dilution in that tank you need to double the amount of Rodinal concentrate, to 300 ml.
That would be enough to develop 30 sheets, which would be a waste of developer if you're only doing 15.

You mentioned in another post that you only had 5 hangers.
To get a 1:50 dilution in your tank you would still need 300 ml of concentrate, which would be a huge waste of developer.

- Leigh

cosmicexplosion
2-Aug-2012, 05:08
Thank you so much Leigh
That explains why things were not going so well
My negs generally looked like waves coming up a beach
Going thinner the closer to the top of the tank
Even after agitation
Though some where even
I am not sure based on 10 ml per neg I used enough, and maybe
They all might have turned out bit better

Oh well I'll stick to tray style till I get more hangers or build a smaller box
Thanks very much for the tip
Incidentally do you put your negs facing up or down?

Thanks
Andrew

Leigh
2-Aug-2012, 05:52
Incidentally do you put your negs facing up or down?
I do emulsion down. Much less chance of scratches that way.

I also use the dimple-bottom Cesco trays, so the surface area that can contact the emulsion is very small.

Good luck with it.

- Leigh