We’ve been using the standard G7 profiles to print with and use as input/emulation profile in our proofing rip. Now we’re trialing FM screening and they tell me we will need a custom profile to be able to have proof match the press sheet more precisely, although from our first runs our standard proofing is looking pretty good.
Anyway, I haven’t done this in a while so did I do it correctly? When printing the curves runs for G7, after the curves were made, I applied them in the rip, output new plates with the curves applied, had them print those, saved 10 good targets from that run, measured in MeasureTool and created a profile in Profilemaker and then used that in my proofing rip as input/emulation profile instead of the standard G7 one we used before.
The result is no better or no worse, better in some colors, worse in others so basically a wash. Does this sound like I did the profile creation and applying correctly? I was wondering if I would get a close match if I would now use my new profile for plating and proofing?
You did it exactly right. I like that you’re getting multiple targets from your run so you can get a good average when making your profile. Your getting similar results using the two methods pretty much sums up why different people go in either of these two directions.
You can 1] use industry standard profiles to proof to and keep your press holding to that standard - in this case G7. Then your work is keeping your press to that standard. In this case, you might check from time to time that your press is staying close by using the G7 verify section of Curve2. There you can drop in any kind of target you have measured - for example the 54-patch IDEAlliance control strip. It will tell you how close you are keeping to G7.
Or you can 2] make a custom profile of the press when it’s as close to the standard as you can reasonably make it. Use that custom profile in your proofer. Presumably this would create a closer match between proofer and press. (How close you are to the standard depends on how well you did the G7 steps.) Of course you still have the usual variability of the press, your measuring device, the interpretation of the profiling software, etc. so individual results may vary.
As an interesting side note, this is part of the reason we advertise that the VPR function in Curve2 can improve your profile accuracy. When your measurement file is curved via software using the same curves used to curve the press, then any variability in that second run is eliminated. There’s always a possibility that the 2nd run you did using the curves had some variability that would effect the accuracy of those profiling targets.
Yep. There’s a “G7 Verify” button that puts the software into a mode where you can put any kind of measurement file in there. (It doesn’t have to be a P2P target.) The measurement can be compared to the G7 standard or a specific run. See page 34 in the Curve2_Guide.pdf for all the details.
I think when “they” said that you would need a custom profile for FM screening to use in your proofing system, they were probably assuming you were using one of the standard G7 profiles (GRACoL1, SWOP3, SWOP5,…) in your proofing system. If that were the case, then needing a custom profile for FM was an accurate statement…a typical G7 calibration that is targeted for, say, GRACoL colorimetry but printed using FM screening will NOT match a proof done using the standard GRACoL profile. The color gamut (gamut “volume” actually) of FM screening, especially in the quarter-to-midtones, is quite different than AM screening.
Custom FM profile notwithstanding, I would question your use of a custom press profile for your proofing system on philosophical grounds. Most of us “G7 Experts” would strongly suggest that you should NOT create a custom profile of your press for proofing but instead build your proofing system around either one of the standard G7 data sets or ICC profiles. While the custom profile will provide a better match between proof and press, this sort of defeats the purpose of standards-based proofing and pressmanship. In any case, you certainly could not suggest to your customers that you’re providing a “GRACoL” proof when in fact you’re using a custom press profile for proofing.
In my opinion, custom press profiles for proofing should be reserved for non-standard inks, substrates and screening methods…which your use of FM screening would fall under. Even in the case of FM screening, I would suggest that using a device link profile to “color-manage” the press back to the standard GRACoL profile is a better approach since it allows you to continue to proof using the standard GRACoL color space. The benefits of FM screening would still be evident with better press stability and sharper rendering of contone images.
Ok Terry, i see what you’re saying about the standard but we are our own customer so only have to please ourselves as far as whether we run to a certain standard or no.
I have never used a device link and don’t have software to make one (unless the new i1 Profiler does that?) but in the scenario you presented we would plate to the standard Gracol profile, print targets on press with our FM screening, create a custom profile from that data. Then at that point we would separate our files using that custom one and then device link to the standard Gracol one?
Seems like an extra step to me, but like i was saying we don’t have to meet a standard to please customers, we are just trying to have a stable, consistent process with as good a match between proof and press as we can.
So why not just use the custom profile to make proofs if that will give a good representation of the press sheet?
Not arguing or debating, just asking questions, trying to learn.