Differences between Tank and Minilab

[zehner21]

Ciao!
I was wondering: are there any tangible differences between developing a colour film with a minilab and a tank?
I don't develop colour film at home, and I have found two services that could do it for me. One uses a standard c41 minilab, the other uses a tank with manual inversion etc.

Thanks

 

[TheFlyingCamera]

The manual inversion, if done properly with chemistry kept in temperature and pH tolerances, will be more likely to not have scratches and/or dust in your film at the end of the day. Minilabs use rollers to pull the film through the chemicals. Rollers get dirty, attract particles, chemical encrustations, etc, as does open multi-gallon containers of chemistry kept at near 100 degrees F. Dip-n-dunk or hand-processing, while it won't completely prevent these things especially if the lab techs are not zealous in their maintenance and/or rigorous in their process, does greatly cut down on the possibility. I'd send each lab a test roll that doesn't matter to you and see which lab produces better results.

 

[zehner21]

Unfortunately, I must send at least 4 rolls for having them developed by "hand". But thanks, you've been very informative

 

[Ian Grant]

The professional labs I used for C41 switched to minilabs and the quality was always excellent.

Ian

 

[TheFlyingCamera]

Ian- it's not that a minilab can't produce good results - it certainly can. The $64,000 question is, is the lab doing proper and routine maintenance on it? If they get lazy, film will get scratched and/or dusty. For that matter, any lab whether hand-tank, dip-n-dunk or minilab powered, can damage film if they're lazy. But the odds go up even with good maintenance if the film is constantly being rubbed against by rollers throughout the development process.

 

[AgX]

The manual inversion, if done properly with chemistry kept in temperature and pH tolerances, will be more likely to not have scratches and/or dust in your film at the end of the day. Minilabs use rollers to pull the film through the chemicals. Rollers get dirty, attract particles, chemical encrustations, etc,..

One can employ undercut rollers that do not get in contact with the image area.

 

[Ian Grant]

Ian- it's not that a minilab can't produce good results - it certainly can. The $64,000 question is, is the lab doing proper and routine maintenance on it? If they get lazy, film will get scratched and/or dusty. For that matter, any lab whether hand-tank, dip-n-dunk or minilab powered, can damage film if they're lazy. But the odds go up even with good maintenance if the film is constantly being rubbed against by rollers throughout the development process.

I started writing then deleted a comment on that in my post.

About 12 years ago I installed some equipment on test at a local pro lab, and photographed the owner using it for a press release. He took my film (120) and I was very surprised when he fed it into his mini lab film processor. While it processed we had a long talk about minilabs etc & the quality. All his print work stations were derelict and he now had one girl running an optical minilab which he was about to replace with a Noritsu or Fuji Frontier.

Terry had been a service technician for Durst UK, the old Kurt Jacobson (who wrote Developing, & later Enlarging) Pavelle colour company who's Pavelle equipment was later sold under the Durst name. He made that exact point that quality was totally down to the operator and it had less to do with the equipment and was totally about the cleanliness and regular maintenance as well as monitoring of the process.

Ian

 

[AgX]

The major difference is that hanger- and rotary-machines are much more versatile. Each bath can easily be changed in constitution and processing time. With roller-tranport machines in general this very much depends on design. And with minilabs there typically is no variation possible.