Agfa Copex HDP13 in C41 (cross-processed black and white microfilm)

If you’re new to my blog, check out the first part of my adventures with HDP13.

A short re-cap. HDP13 is a microfilm that was manufactured by Agfa. It was made in Belgium. The last rolls of film in Agfa Belgium was made somewhere around 2004. My roll has an expiration date of 10/2011, which probably makes it one of the last rolls to get manufactured.

Finding information about this film is difficult. Agfa made a range of microfilms, there’s at least HDP06, HDP10 and HDP13. And then they have Copex Rapid PET06 and PET13. The numbers are related to size, the two Copex Rapid ones are just different thickness of the film base. So probably in essence they made just two different emulsions.

I have found some random bits and pieces about these films online from various sources:

  • Rapid is supposedly better than HDP13 for pictorial work due to less steep graduation curve but HDP13 shows better sharpness

  • HDP might stand for for High Definition Panchromatic

  • Copex Rapid is panchromatic and “High speed”

  • Gigabit film is really Copex Rapid with a custom developer (I have a blog post about Gigabit coming during summer, lots of stuff to test, so little time). Gigabit film is ISO40 in its own developer

  • HDP13 is somewhere between ISO12-25 depending on developer used

Somewhere, at some point, I read about using C41 developer for high contrast film (the article was about Tech Pan), and since I have a bulk roll of HDP13 and some C41 developer that is no longer good enough for important work, this was a good occasion to try it out. I have not been able to find much information about cross processing black and white film in C41 developer, just some people who (falsly) claim that it will just render blank negatives.

So, for my first trial I started out with ISO25 and bracketed one stop over, ISO12. The developer was at an ambient 22c, and I souped the negs for 10 minutes with just a few calm inversions. As before, I shot with my Hasselblad, 80/2.8. Hence the funky XPAN like form factor.

The negs were very very thin.

Second try, I tried again ISO25+12 and instead did 25c and 20min. The negs were much better, but still very thin. There was some weird wavy effects in highlights, and I remember reading that Gigabitfilm and Tech pan require VERY INTENSE agitation the first 30 seconds of contact with the developer.. I need to try this.

Third and final try for this time, I increased the temperature to 30C and time to 25min. ISO12. Very intense shaking for the first 30 seconds, a few good taps, and then just one inversion per 5 minutes.

The improvement was marginal at best. My metering might have been off since I used a flash. I also tried some long exposure ones, but I know nothing of the reciprocity characteristics of this film, so I did not adjust for it at all. But still, I find this surprising. With usual black and white development, an increase of 5c in the developer temperature HALVES the development time. So 25min in 30c should equal to around 12min in 25c, and try #2 was 20min. Could it be the low agitation interval? Or is my C41 developer just plain dead now?

It does however - have nice mids now. It’s very low contrast. After tweaking with levels in photoshop, you do actually get an useable image now with pretty mellow tones. If i were to use this film for pictorial work again in the future, I would probably increase the temperature yet again. But at some point the emulsion will start to melt. I would probably try 32c, 30min, and do agitation every 3 minutes or so.


This is not a good general use film. The film base is sooo thin, they attract every speck of dust within a miles radius, if you handle them without gloves you will get fingerprints, if you try to wipe them you will scratch the surface. You cant even wipe them with a microfiber cloth without scratching, that’s how delicate they are!

Then there’s the fact that they are not perforated, it kinda sorta works using the ‘blad, but sometimes you roll too much into the film can, and then they get too tightly wound and you cant advance the film in camera. And you have to flip the camera 90c if you want a landscape oriented shot, otherwise you will get a portrait shot but very very tall. Which looks stupid, and is impossible to compose shots with.

However, having said that, it is film that can be found very cheaply on the ebays. And it is fun to try out new things. And it is totally grainless and crazy sharp. If you have a datasheet on HDP13 I would like to have it please! If you have any experience of your own with Agfa microfilms, please write in the comments!


It seems that Adox CMS20 is also HDP13:

“Adox CMS 20 II is fresh production Agfa-Gevaert HDP microfilm. The former CMS 20 (=Spur Orthopan UR film) is from a former version of Agfa HDP 13. “. Source.

And for this, we can actually find a datasheet.