Dot Gain - Basic Questions

Just wondering how you came up with these numbers to be your target dot gains and what do you use for a cmyk profile?

We’ve recently implemented G7 and it seems to be working well. We do have a way to measure Lab though because previously we were using a custom press profile. We only have one press that we print color on. I did find that to be the closest match I’ve had press to proof but as things changed at the press I was constantly tweaking the curves to match whatever gains they were getting at the time, we were having some press issues and had it worked on 5-6 times over the last 2 years. Anyway after testing the custom press profile some I found that it wasn’t as smooth as the “official” profiles (swop or g7) so what we’ve done is to implement G7 but I did pull the G7 data into Profilemaker and created a profile for our use with MaxGCR. We were using MaxGCR before and it seemed to make more stable color on press, use less cmy inks. Also, to my way of thinking, and I could be totally wrong, if anyone can tell me yea or nay please do, but using high GCR with the G7 method seems like it would make it even easier to control gray balance as you’re taking a lot of the cmy colors out of the equation and replacing them with just k, especially in gray\neutral areas?

The one thing I miss about SWOP seps or custom press profile is we all knew exactly what the dot gains at press were supposed to be: 22-20-20-18 kcmy. Where with G7 curves it’s not so obvious if something is off to see if the gains are ok.

The biggest thing regardless of what standard you choose to use is that it will make your printing more consistent if you’re watching and controlling everything the best you can in prepress and at press. Consistency equals repeatability, giving you confidence that the jobs going to press will match the proof if nothing else happens along the way and if it does now you’re familiar with all the variables and know what to look for to be able to correct the problem.

Because of inconsistencies I’ve seen from our press I began reading each proof, film and plate going out of prepress. Sounds excessive? Maybe, but I’ve learned exactly what our variations are and know for certain that the plates I’m sending out are exactly like the last ones that went out and matched the proof really well, so if the next set doesn’t, it’s not the plates and they can start checking out things at the press instead of me having to prove to them first that its not the plates. More peace of mind for me and less troubleshooting what almost without exception was a press variable that had changed.

Just my…probably .10 cents worth.

Terry