How to check if Photo developer did any changes to your prints?

[elutris]

Hi,

I heard that there is a way to check if the photo developer did any alterations to your prints. You can check by looking behind the photo. If I am not wrong, N N N N (or is it X X X X or some other alphabet) means that no alteration was done and what you see is basically what you took.

Can someone confirm this? And what do other variations of the alphabets mean?

 

[Ian]

The NNNN Codes represent the following

Cyan
Magenta
Yellow
Density

The actual numbers represent the amount of operator adjustment, eg NN2N or NN-1N and are not indicative of anything else as the printing machine has already made a preliminary analysis of the negative before manual intervention. The machine based analysis is NOT printed.

An un-official qualification in the pro-lab industry is that you must be using either a Bremson or Kodak video analyzer for proofing. In this case the prints wouldn't have the NNNN codes but a DRGB code.