Rodinal / R09 o.s. you can use 1+10 (paper) from 1+25 (film) , 1+50, 1+100 or even more in dilution. Just remember to use at least 5ml-5,5ml for each 135-36 or 120 roll film (equivalent surface area) concentrate Rodinal. In a higher dilution the sharpness will increase and above 1+75 you can get even some staining effects. Also 1+50 has a more compensating effect then a 1+25 dilution. Rodinal / R09 o.s. is a high acutance type developer. Apart from the mentioned characteristics a higher dilution will give less contrast hence some people are using 1+150 for micro film development or Technical Pan films.

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Rollei Advanced Technical Pan (ATP1.1) in Rodinal 1+150 for 6:30 minutes at 20C.