My last four or five films have turned out complete shite, and I don't really know what might have caused it,.

My main suspect is the ascorbic acid I bought from Krydder.no.
Anyone else have experience with that?

the vit c i buy has been from 3 sources
1 - a pharmacy
2 - a national ( usa ) health food chain ( whole foods )
3 - a national ( usa ) heath food chain ( trader joe's owned by aldi in germany )
i have only gotten 100% vit c / ascorbic acid

and never had problems ...

when you say they turned out bad, what do you mean---- splotchy development? excessive grain? non-development ?
have you used the other ingredients together before now ( same batch of soda, same batch of coffee ) ? and if your vit c doesn't say 100% ascorbic acid you will probably run into trouble.
and ... sometimes coffee brands change the amounts of coffee in their instant ... it is never 100% robusta .. the less robusta the less caffic acid, the less development.

I've read of others having problems with ascorbic acid from the chemists here in Norway. It may be that since its meant for ready consumption, and not for making jam, the granules are coated? I use the Santa Maria stuff you get in the shops in Sweden. Its for making conserves and seems pure enough.