I thought that, unlike processing B&W, the C41 process is highly standardized so really no room for doing it incorrectly (except for not following the process)?
That's correct .
Unless you've pushed or pulled the film and that'll need special attention .
With fresh chemicals , correct handling etc it should give consistent results .
I had one roll back once that was grossly underdevoped , with some frames being almost clear . What gave it away that they were at fault ( asides from the B&W films before and after it being exposed spot on ) was the writing in the film's rebait also being barely visible in patches .
Even an unexposed roll of film will come back from being developed with the writing nice and bold .
They then admitted that the nozzle was blocked on one of the chemicals in the machine .
Turns out they thought it was odd a few other people's film were also " underexposed" that week but blamed the customer.
Bit obvious when all the film's coming out like that , that something might be wrong ?
As the amount of processing for c41 has gone down their chemicals don't seem to be as fresh as they should be resulting in badly developed negatives .
Muddy , low contrast negatives from the labs are annoying me , which is why I've started developing my own in batches of 15 ( as that's what the kit recommends ) .
If I need a single roll if c41 developing, I'll send it out , but I need to find somewhere new to send it .
As I said earlier , for B&W I've developed my own for about 35 years , so there's always some stop and fix ready to use , and I tend to use a one shot developer anyway , so it's always fresh .