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January 1, 2016

Thermal Printer: Text Prints Good But Graphics Are Degraded

Hello all!
This is my first post to the form so please be patient with me.

I am having a strange problem where I can print text out just fine (down size 7 font with good crisp/sharp lines) but when I print anything that is not text, like a barcode, it comes out grainy or really degraded. I have attached a PDF with two pages - one the document to be printed, the other is the document printed with the problem above.

I have a Eltron LP2442PSA thermal printer. I'm running Mac os X 10.9.5 and using a Keyspan 19QW USB to serial converter. For software I am using:
● CUPS 1.7.2 with the Mac's built-in Zerba EL2 printer driver
● Foomatic-RIP 4.0.6
● Ghostscript 8.71
● Serial Print Enabler 1.5 (http://webpages.charter.net/mbroughtn/serial_printing.html).

I am completely at a loss as to why this is degrading graphics so bad. I have tried various sized graphics —from the correct size to oversized - and it still does the same thing. My original thought was that the raster part was messing up in CUPS. But after fiddling with drivers and filters for 6 hours, I can't confirm or deny it.

Any help or thoughts would be greatly appreciated!

Click Here!