I used to work with Rodinal and Tri-X, down-rated to an exposure index of around 250 to 320, with Rodinal diluted to 1:100, going around 12 minutes at 68 degrees Farenheit, with 10 second "roller pin style" agitation in 4-roll 35mm steel tanks, with 10 seconds of agitation given at the top of each minute.
Rodinal produces big, crisp grain on Tri-X. HC-110, DIlution D, or D76 wither undiluted or cut 1:1 with water, produces smaller, tighter grain, and I think, better overall tonality.
Here's a Rodinal shot I made in dim,diffused light.As you can see, there's a LOT of grain in the large expanses of smooth, one-toned subject matter. I actually grew tired of how "grainy" Rodinal made my Tri-X look, and I went back to HC-110.
Warning: potentially NSFW; implied nudity
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