Firstly, hello! This is my first post, and I was hoping to find a great place to gather information on film photography, as I've recently jumped down this vast rabbit hole with no way out. I've been doing film photography for a year and a half, and for half of that time, I've been developing and scanning my own film. I had no prior knowledge of photography, but since then, I've learned a lot.
I started off using Rodinal, which was a great introduction to developing my own film because, well... all the development times were available! Everything was handed to me on a silver platter. However, very recently, I moved away from Rodinal, as I started to dislike the way film looked when developed in it, just my personal preference. I bought Ornano Gradual ST-20 from Bellinifoto, and I absolutely love it! I especially love how Fomapan looks when developed with ST-20.
But there was a small caveat, and I knew I needed to get my feet wet here... That is, finding development times for films that haven't been developed with ST-20, and there are quite a lot.
As an example, right now, I have two rolls of Adox HR-50 that I would love to develop with ST-20 and find the right development times for. But the question is, how? What is the best way to do this?
For now, I thought I would research and try to look at possible developers that behave similarly to ST-20. I thought that Adox FX-39 seems to be a suitable candidate, as I was comparing development times currently published, e.g. (both films are hydroquinone but FX-39 is not phenidone-based I believe?)
While similar, I feel like this logic is full of BS and flaws but I was thinking that a possible baseline time could be between 7:30, 8 minutes or 9 minutes?
But how can I be sure before I go off developing a roll and have it be absolutely useless?
Do bear with me as its all kind of new to me and I'm learning from any resources I can find
so I would really appreciate any information possible!
Thank you!
I started off using Rodinal, which was a great introduction to developing my own film because, well... all the development times were available! Everything was handed to me on a silver platter. However, very recently, I moved away from Rodinal, as I started to dislike the way film looked when developed in it, just my personal preference. I bought Ornano Gradual ST-20 from Bellinifoto, and I absolutely love it! I especially love how Fomapan looks when developed with ST-20.
But there was a small caveat, and I knew I needed to get my feet wet here... That is, finding development times for films that haven't been developed with ST-20, and there are quite a lot.
As an example, right now, I have two rolls of Adox HR-50 that I would love to develop with ST-20 and find the right development times for. But the question is, how? What is the best way to do this?
For now, I thought I would research and try to look at possible developers that behave similarly to ST-20. I thought that Adox FX-39 seems to be a suitable candidate, as I was comparing development times currently published, e.g. (both films are hydroquinone but FX-39 is not phenidone-based I believe?)
Film | FX-39 (1+9) | ST-20 (1+9) |
Ilford FP4+ | 6:00 | 6:30 |
Ilford HP5+ | 14:00 | 12:30 |
Kodak TMax 400 | 10:00 | 12:00 |
Adox HR-50 | 7:15 | ??? |
But how can I be sure before I go off developing a roll and have it be absolutely useless?
Do bear with me as its all kind of new to me and I'm learning from any resources I can find

Thank you!