wentbackward
Member
I've experienced this problem in the past, in particular with the HR40 on an IQ160. In fact I'm on my 3rd back, however the problems were much worse than shown here and were all visible lines showing, not just the centre one.
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I've experienced this problem in the past, in particular with the HR40 on an IQ160. In fact I'm on my 3rd back, however the problems were much worse than shown here and were all visible lines showing, not just the centre one.
Peter, Yes, my current back seems fine.So the back you're having now doesn't show this?
Peter
I understand the calibration can be done remotely with an LCC exposure.I think the greyscale conversion on mid to lighter tones can accentuate the sensor seams. Also if you push too hard in processing C1 it can cause it to be more noticeable.
I had this problem last March, and did send my IQ180 in for recalibrating, and it did help ... at least I haven't noticed it since.
It's not a problem of just the thin join line where the sensor segments abut - you wouldn't notice that. It's a problem of entire halves/quadrants/sixths of the sensor being read out through different channels, with their own amplifier characteristics.In the past, when we were discussing the possibility of a square (eg 48mmx48mm) CCD, it was often considered that the cost would be prohibitive. I think at that time, few of us realized that the CCD was actually being "stitched" together?
For this problem, the root cause is the stitching. What the software/firmware can do is just to "hide the line". Because there is no physical CCD area overlapping for this kind of "stitching", the tolerance must be very high.
If by "camera" you mean digital back or sensor, that is not always the case.Woody,
It's not really just an IQ issue. Any camera can exhibit this if abused sufficiently.
It also depends on other factors like how the readout channels are laid out, and how fast the data can be read, for example DSLRs have 8~12 readout channels that read data off the sensor in rows, and you never see this kind of anomaly.If by "camera" you mean digital back or sensor, that is not always the case.
As I explained here, some Kodak-sensored backs will never show this problem, because there is only one readout channel for the entire chip.
Dalsa sensors are more likely to show it because they use multi-channel readout architecture in all of their CCDs. That makes them faster to read out, but the penalty is what you see here.
I hope that with recalibration, it can be cured to everyone's satisfaction.
Ray
BothEd, are you using Schneiders or Rodies?
Peter