Thank you for this investigation and for sharing your data! I was 100% convinced that those two films have at least the same emulsion until the fluorescent light images. The difference is just a little over what I'd assume to be a manufacture variance within a same product, espexially with the other shots being so close. Since fluorescence lighting has a very specific emission spectrum it would theoretically indicate a strong difference in spectral sensitivity. However i suppose that could be due to the batch of rollei IR being older and one specific dye has died down. Great work overall!
I use the big rolls of Agfa Aviphot pan 200. I have used developers like D76, Rodinal , Pyrocat, and 510 pyro. They all work differently for sure. With Rodinal I get 200-400 speed using the 1+50 for 8min and with d76 I was getting 100 speed 1+1 for 15 min. Both pyrocat and 510 had to have higher concentrations to achieve 100 speed. 1+1+50 and 1+50. Both for 10 minutes. Edited pyro concentration were wrong
On 400S maybe being just worse IR400 - are there any other examples of binning in the film industry? If Ilford are making FP4 and decide it's not quite good enough, do they just call it Kentmere 100? Also I love the IR shot of the tree :)
Unfortunately I'm not in a position where any of my (few) contacts are willing to talk about this - which is entirely fair - so it's purely speculation on my part. I know we've seen screwups be spun into alternate products, like Lomo Purple Petilant (damaged emulsion) and Cinestill Redrum (120 mistakenly rolled backwards), but that's quite different. I haven't taken Maco's datasheets at face value in a long time, but the IR sensitivity was the real golden egg for this test for me. I also couldn't remember the word "binning" for the life of me when I recorded this, so thank you for easing that little nag in the back of my head! And thank you! I really want to go back and shoot it slightly differently on 4x5 over the summer.
It would be interesting to see a similar comparison between APX400, RPX400 and Kentmere400, which some people claim are one and the same emulsion. They are definitely closely related, but the same?... Also, what could be the underlying chemical/physical mechanism for different developers giving different film speeds depending on the type of light being used, instead of one developer giving a consistently different speed from the other? Is there some interaction between the developer and sensitizers?
Keep in ming that its ISO speed is close to 50, not 200. Aerial films speed is determined using completely different standard, so 200 here is not your usual ISO 6:1974
I've recently watched David Hancock's video about Retro 80S. He found and commented on the fact that this film looses sensitivity when pushed even a stop. His explanation is roughly: the emulsion on these films is very thin and sensitive to overdevelopment. His recommendations were to basically always pull the film 1 stop, though box speed is mostly fine. Could this be the reason for your inconsistent development results at the start?
I don't think so. Rollei 80S and RPX25 being the same film, 80S is already a pushed version of RPX25. So no wonder 80S doesn't like being pushed even 1 stop. Same goes for 400S being already pushed (it's the same as Superpan 200, they're both respooled Agfa Aviphot 200). Those original AFGA films were made for aerial surveillance, so they needed to be contrasty. My guess is their original ISO ratings (80 and 200) was decided to get that needed contrast. If you test them both you can find Rollei 80S (AGFA Aviphot 80) has a better tonal range at 25 ISO. And Rollei 400S (or Superpan 200) work better at 100-125 ISO.
@@endingmirage No, it's garbage with excessive contrast and a disgusting substrate. if you need a similar photographic film, then you can easily buy the original AGFA avifot. we sell it everywhere in reels of 30, 40 and so on meters. and it sells cheap. but it's better to buy a photographic film from FOMA, it's cheaper than Ilford. этот роляй нам ненужон.🤣
I thought I knew what true love was until I met Rollei IR.
(so excited you made a video about these two btw!)
Thank you for this investigation and for sharing your data! I was 100% convinced that those two films have at least the same emulsion until the fluorescent light images. The difference is just a little over what I'd assume to be a manufacture variance within a same product, espexially with the other shots being so close. Since fluorescence lighting has a very specific emission spectrum it would theoretically indicate a strong difference in spectral sensitivity. However i suppose that could be due to the batch of rollei IR being older and one specific dye has died down. Great work overall!
I use the big rolls of Agfa Aviphot pan 200. I have used developers like D76, Rodinal , Pyrocat, and 510 pyro. They all work differently for sure. With Rodinal I get 200-400 speed using the 1+50 for 8min and with d76 I was getting 100 speed 1+1 for 15 min. Both pyrocat and 510 had to have higher concentrations to achieve 100 speed. 1+1+50 and 1+50. Both for 10 minutes.
Edited pyro concentration were wrong
On 400S maybe being just worse IR400 - are there any other examples of binning in the film industry? If Ilford are making FP4 and decide it's not quite good enough, do they just call it Kentmere 100?
Also I love the IR shot of the tree :)
Unfortunately I'm not in a position where any of my (few) contacts are willing to talk about this - which is entirely fair - so it's purely speculation on my part. I know we've seen screwups be spun into alternate products, like Lomo Purple Petilant (damaged emulsion) and Cinestill Redrum (120 mistakenly rolled backwards), but that's quite different. I haven't taken Maco's datasheets at face value in a long time, but the IR sensitivity was the real golden egg for this test for me.
I also couldn't remember the word "binning" for the life of me when I recorded this, so thank you for easing that little nag in the back of my head!
And thank you! I really want to go back and shoot it slightly differently on 4x5 over the summer.
Kentmere 100 has its own recipe - Kentmere was once a separate company
Do you have any experience developing these in Caffenol?
I don't, sorry.
It would be interesting to see a similar comparison between APX400, RPX400 and Kentmere400, which some people claim are one and the same emulsion. They are definitely closely related, but the same?...
Also, what could be the underlying chemical/physical mechanism for different developers giving different film speeds depending on the type of light being used, instead of one developer giving a consistently different speed from the other? Is there some interaction between the developer and sensitizers?
ill continue simping rollei 400s then
Neat beer coasters 😏 interesting video!
Represent 🙌
The film gods blessed me with this video.
Keep in ming that its ISO speed is close to 50, not 200. Aerial films speed is determined using completely different standard, so 200 here is not your usual ISO 6:1974
I've recently watched David Hancock's video about Retro 80S. He found and commented on the fact that this film looses sensitivity when pushed even a stop. His explanation is roughly: the emulsion on these films is very thin and sensitive to overdevelopment. His recommendations were to basically always pull the film 1 stop, though box speed is mostly fine.
Could this be the reason for your inconsistent development results at the start?
I don't think so. Rollei 80S and RPX25 being the same film, 80S is already a pushed version of RPX25. So no wonder 80S doesn't like being pushed even 1 stop.
Same goes for 400S being already pushed (it's the same as Superpan 200, they're both respooled Agfa Aviphot 200).
Those original AFGA films were made for aerial surveillance, so they needed to be contrasty. My guess is their original ISO ratings (80 and 200) was decided to get that needed contrast. If you test them both you can find Rollei 80S (AGFA Aviphot 80) has a better tonal range at 25 ISO. And Rollei 400S (or Superpan 200) work better at 100-125 ISO.
this is a repackaging of Avifot's garbage technical film. we call it disparagingly -роляй!
It is not garbage most of the time if you know how to проявлять её. Not Ilford film, yes
@@endingmirage No, it's garbage with excessive contrast and a disgusting substrate. if you need a similar photographic film, then you can easily buy the original AGFA avifot. we sell it everywhere in reels of 30, 40 and so on meters. and it sells cheap. but it's better to buy a photographic film from FOMA, it's cheaper than Ilford. этот роляй нам ненужон.🤣
I love HR-50 (in Rodinal) for landscapes. So Aviphot is not garbage IMHO.