Hi Jonathan,
I oversee production of our toner based Versafire, similar to your press. We perform daily recalibrations in order to maintain G7 output.
We do this with both a Calibration & Profile applied. Just as your engineering team recommends, we perform a daily recalibration to bring the machine back to a repeatable baseline state. The output of this baseline state is NOT inherently G7, but it is a repeatable output of color by recalibrating back to that baseline state.
To obtain G7 output, we apply a profile which remaps the baseline state to output G7. That profile will always sit ontop of the press's calibration.
You recalibrate the machine to a repeatable baseline state every morning. You do NOT re profile - you do this once, and it continues to sit ontop of the press's calibration.
So in house, you would technically perform 2 different types of calibration to the machine. The Recalibration to baseline state (every morning), & Profiling (do this once - always remains applied on top of the calibration)
1. (scan large color patch chart printed after calibrating machine & create profile) --> do this once, Profile remains applied ontop of machine's calibration.
2. (Recalibrate machine to repeatable baseline state) --> do this every morning (per your engineering team)
I hope this helps to clarify some things.
Thank you
-James
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James Ryan
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Original Message:
Sent: 08-08-2025 01:30 AM
From: Jonathan Quisit
Subject: Quick Question on G7 Calibration Frequency for Electrophotograhic machine
Hi Timothy,
Thank you for your sharing. Just a follow up question.
Our device engineering team recommends performing daily controller calibration to stabilize output. However, we've observed that this process may override or disrupt previously applied G7 calibration curves, potentially leading to shifts in gray balance and tonalityeven if density targets are met.
Given this, I would like to clarify:
Again my question, is it necessary to reapply G7 calibration after performing daily controller calibration, even if the system appears stable?
Does daily controller calibration inherently interfere with G7 curves, and if so, what best practices do you recommend to maintain G7 compliance without over-calibrating?
Is there an official guideline or SOP from Idealliance on how to balance internal device calibration with G7 methodology for toner-based systems?
I just want to ensure our calibration workflow aligns with G7 standards while maintaining operational efficiency.
Thank you.
Jonathan
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Jonathan Quisit G7 Expert
Regional Solutions Manager
Konica Minolta Business Solutions Asia
Singapore
98334387
Original Message:
Sent: 08-07-2025 11:32 AM
From: Timothy Quinn
Subject: Quick Question on G7 Calibration Frequency for Electrophotograhic machine
Hi Jonathan,
Here's how I think about it:
If your internal engine/controller calibration brings the press back to a known, stable state (as it should), then you should perform that internal calibration as often as the device engineering recommends-daily, weekly, or however needed based on usage and stability. That gets you back to the OEM's expected baseline.
G7 calibration, on the other hand, is external to that system, it sits on top of the internal calibration. Once G7 curves are applied and the system is in compliance, there shouldn't be a need to recalibrate to G7 unless something in the system has changed significantly.
According to the G7+ training, if you need to recalibrate often, it's a sign that the internal system isn't holding stable, and the priority should be to figure out why that drift is happening. In a well-maintained system, G7 recalibration should be rare, only when necessary, too often can introduce variations, and re-profile seldom as possible because every profile produces slightly different color.
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Timothy Quinn
Nazdar Consulting Services
G7expert @gmail.com
G7expert @yahoo.com
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Original Message:
Sent: 08-06-2025 11:27 PM
From: Jonathan Quisit
Subject: Quick Question on G7 Calibration Frequency for Electrophotograhic machine
A quick question regarding G7 calibration, just wanted to seek some clarification and hope to get an expert opinion on this.
I'm currently having a discussion about G7 process to internally and received a query from our engineer about how often G7 calibration should be performed on a Konica Minolta Production Printing (KM PP) machine. I don't recall this being explicitly covered in the course materials. Should we follow the machine recommendation?
According to our service manual, it recommends performing G7 calibration at least once every 3 months. However, given the inherent variability of electrophotographic systems, I'm wondering:
Would it be acceptable to rely on regular engine/controller calibration instead, assuming it maintains consistent output?
Appreciate any insights you can share. thanks in advance!
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Jonathan Quisit G7 Expert
Regional Solutions Manager
Konica Minolta Business Solutions Asia
Singapore
98334387
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