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I had to redo my JVC HD350 calibration (with external VideoEQ Pro CMS/greyscale/gamma) due to a flicker on the normal lamp mode, which is cured by using high power. Before I started, I took a measurement with my previous normal lamp calibration settings applied, then did another run with the same settings having only changed the lamp setting.
I thought this might be useful to show just how much effect the lamp setting (and no doubt changing the lamp) makes to the picture. I don't know if it was a slight 'glitch' in the reading, but notice that the gamma is slightly different between these two runs. I've seen it written that the JVCs gamma drifts over time as the lamp ages, this seems to show a measureable difference in gamma just by changing the lamp power. The 20% extra red was what surprised me, I don't know if this is typical or whether this might be a side effect of the wandering arc causing my flicker? Note that the flicker wasn't occuring during the normal power run, it tends to start after being on for a few hours, but last night it had been on for 4 hours at least. However, I know it might come back at any time, so I've deceided just to stick with high power and a lower iris setting instead (maximum ON/OFF contrast in this configuration as well).
For information: The readings are taken from the projector with diffuser in place using an offset calibration taken from the screen. The pre readings are 'Normal' lamp and the post readings 'High' lamp power.
Low lamp pre high lamp post.pdf 142.1376953125k . file
I thought this might be useful to show just how much effect the lamp setting (and no doubt changing the lamp) makes to the picture. I don't know if it was a slight 'glitch' in the reading, but notice that the gamma is slightly different between these two runs. I've seen it written that the JVCs gamma drifts over time as the lamp ages, this seems to show a measureable difference in gamma just by changing the lamp power. The 20% extra red was what surprised me, I don't know if this is typical or whether this might be a side effect of the wandering arc causing my flicker? Note that the flicker wasn't occuring during the normal power run, it tends to start after being on for a few hours, but last night it had been on for 4 hours at least. However, I know it might come back at any time, so I've deceided just to stick with high power and a lower iris setting instead (maximum ON/OFF contrast in this configuration as well).
For information: The readings are taken from the projector with diffuser in place using an offset calibration taken from the screen. The pre readings are 'Normal' lamp and the post readings 'High' lamp power.
Low lamp pre high lamp post.pdf 142.1376953125k . file
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