The effect of c-41 processing in different labs

[digiconvert]

I am in the process of calibrating a Labometer and can get good prints consistently from certain negtives but not others. I have tried two Portra 160VC films - one processed at ASDA and the other at a pro lab. The ASDA negatives come out pretty well using the Kodak 100 standard settings but the other negs come out dark and red/magenta on this setting.
Can processing make such a huge difference and how come ASDA's efforts seem more consistent than the pro lab ?

 

[Photo Engineer]

This can be the result of using Kodak and non-Kodak C41 chemistry. It can be the result of improper agitation, temperature and a number of other faults too numerous to mention.

And, these faults can be repeated over and over again such that a lab can learn to live with their consistant faults.

PE

 

[Bob Carnie]

There is a thread close to ending that is about minilabs vs prolabs going on right now.
As PE suggests the problems can be endless,
The more volume and the more control strips, monitering and adjustments that are done at some high volume processors seem to produce better results , and this might be what you are seeing.
I have managed E6 and C41 labs and can tell you when volume is in with consistant and accurate monitering/adjustments the film quality is better.

I am in the process of calibrating a Labometer and can get good prints consistently from certain negtives but not others. I have tried two Portra 160VC films - one processed at ASDA and the other at a pro lab. The ASDA negatives come out pretty well using the Kodak 100 standard settings but the other negs come out dark and red/magenta on this setting.
Can processing make such a huge difference and how come ASDA's efforts seem more consistent than the pro lab ?