Konica C350 questions - misc

[Jeff]

Howdy all,

I had such great luck with my first post (problem 100% solved) I thought I'd push my luck and ask a couple more!

1) My C350 seems unaware of paper in Tray 1 (multipurpose tray). The C350 knows the tray is installed, but sees no paper, regardless of size. Any ideas?

2) Copy quality is generally OK. But color copies are a tad off. For example, light blue original data is printed too light. Ran image stabilization and it helped a bit. I ran it without reset. Should I try it with reset? Should I use the gradient adjustment?

3) If I use the gradient adjustment, I do not understand the service manual. Page 3-36 of version 1.0 manual, step # 4. What does that mean?

"Place 10 copies of A3 paper on the test pattern and lower the original cover"...

What EXACTLY do I do? I don't get it. "ON" the test pattern???

Thanks in advance,


Jeff

[Stirton.M]

Tray one paper empty sensor may not be working, either the sensor is not functioning or the flag is missing. It could also be that the machine does now know that tray one is inserted. The only way to know is to go into tech rep mode and do a sensor check from there.

The C350 has its limits as a stand alone machine. Gradation adjustments help a little, but scanning accuracy is limited to the CCD and how the machine sets up its white patch adjustment. Ozone, patch discolouration, CCD age...all can throw off colour accuracy in some way or another. Original image pigmentation can also be a factor. Was it an ink original, printed on another laser/led, direction of print lines relative to scan direction. Scans are subject to text/photo, photo, text modes to name a few, which can also throw more curve. Also 600DPI is a limiting factor.

In short, you will be hard pressed to reproduce a colour accurate copy of the original without a lot of trial and error, and knowing a lot about the original before you attempt to copy it.

In gradation adjust, the recommendation to place 10 sheets of A3 is a subjective need.

A3 I believe is roughly equal to ledger/11x17. You can also do gradation with A4 or Letter size. Its an either/or....both do the same for the most part.

The recommendation is that when you place your scan sample on the glass, the 10 additional sheets are placed over the scan sample and then the doc feeder closed to hold it all as you scan. This is taking the assumption that you are using generic 20lb paper, which when viewed against a light source, can be almost transparent in relation to the brightness factor of the paper. With a few extra sheets behind the scan sample, the density should help keep the paper "white", relative to a single sheet that would shift a bit from the influence of the doc feeder belt.

If you used 28lb paper, super white...98 brightness, you could almost get away with just the test pattern itself and nothing covering it.

This adjustment only affects scanned documents. Reset and stabilize will affect printed data. For best results, install a fiery controller with a calibration tool (ES-1000 for example) for better control over colour accuracy and the ability to reproduce pantones accurately based on the pantone chart when printing anything where colour accuracy is a must.

[Jeff]

Dear M. Stirton,

Thanks for the information. I will check the sensors in tech mode. Thought there might be something I missed. Your information is clear - thank you. I now know what they are talking about with respect to the gradient test and the stack of paper. 10 pages is probably overkill. I am using very bright white (and thick) bond, so I'll stack 3-4 to make sure.

Yes, I know that the C350 is not going to give me art-accuracy, but it could be a bit better. I'll bet reset/stabilize makes it good enough. But I will check the scanned output first, to see if the scanner is at fault (and use gradient to correct, if it is).

Thanks for your fast and generous reply.


Jeff