Another SP-445 Question (Re: C-41 and "Blix Burp")

[mitch.goddard]

Sorry if this has been discussed before but in the few threads about processing C-41 in the SP-445 that I skimmed I didn't see any mention of my particular issue. I have the 1L Unicolor C-41 kit, and so far have only developed two rolls of 35mm with it. While blixing the first roll I had the top pop off of my Paterson tank mid-inversion, spilling blix everywhere and staining my bathroom vanity in the process. I learned the hard way that the gasses formed during this process are no joke. I solved the issue the second time around by agitating with the "swizzle stick" instead of actually inverting the tank (and not actually sealing the lid on the tank) and everything came out great.

My concern is that there's no such solution when it comes to the SP-445. My thought was to loosen the vent cap while blixing, only tightening it to invert the tank and then loosening it again until the next inversion, but figured I would check in and see if anyone else that's doing C-41 in one of these tanks had any tips or tricks to offer.

[koraks]

You need some kind of venting during the first acid bath after the developer. I say 'first acid bath' because in order to prevent spilling your blix, you may consider using an acetic acid stop bath, then (optionally) rinse and then blix. That moves the burping issue to the stop bath, which at least is cheap as chips and no great loss if it wasted. What I generally do with my Jobo tanks is to put in the stop, let it rotate (agitate) maybe 10 seconds and then burp the tank by loosening the lid momentarily. You can usually feel the pressure releasing when loosening the cap. Then the cap goes back on and processing proceeds, and no further (significant) gas buildup occurs. I bet you can do something very similar with the SP445.