In the past few years (not sure how many... 2 or 3) I've developed about 18 rolls of film. Yeah, I'm not a fast shooter.

Anyway, I've used different films and devs in different combos. However, for practical and economical reasons I mostly develop in HC110 or Rodinal.
Most of the combos I use somehow work. I never implemented the zone system completely - I only use it for exposure, then develop according to recommendations I find online. So: no +-N development. As a result I don't really know if my negatives are properly developed at all.

I first felt this problem yesterday, trying to print tmax 400 pushed to 1600 in hc100. I just couldn't make the print work - no fiddling with paper grade / exposure made it right for what I wanted.

So far my observation is that tmax 100 in rodinal has much more contrast than tmax 400 in hc110 (even not pushed). But that's it. I don't really understand how much contrast my negatives should have (I don't have a density meter), other than "they should print normally on grade 2 paper".

Looking at my archive, it would probably help if I had samples of the same scene on different film/developer combos. Preferably metered against a grey card. That would at least provide me with some information how the same scene is recorded in the negative, and probably would show what is under / over developed.

So I'm thinking of setting up someting like this: (this is intentionally low contrast to see the dynamic range of the scene). Correctly developed and printed on grade 2 it should porbably look somewhat like this:

My reasoning is that having a standard shoot would at least give me an anchor, something to compare my results against. To see where I need lower/higher grade, hence probably over/under developed (assuming no N corrections).

I'm also thinking of using DDX as a baseline developer. The reason is that Rodinal gives lover speed and high contrast, and HC110 has the upswept curve, none of which is desired for baseline, normal processing. Xtol could be better, but DDX supposedly lasts 24 months in "a full, tightly cupped bottle", so I could store it in smaller bottles over longer period.

Does any of this make sense?