Digital BW, The Print

I have a predictable pattern of black (Eboni) apparent clogging with my 7800 that someone more familiar with those heads might recognize.

If the printer has sat for a month or so without use, the black channel nozzle check will be blank for about 1/3 or less of the very top left of the nozzle check pattern.  Oddly, I have not really see evidence of the clog in printing when it's just a few lines that are missing.  No other jets have ever been clogged on that printer.  But, assuming it's a clog, I'm suspicious this might be something like ink running out of the head and drying on the lowest part of the head.

Any opinions welcomed. 

Paul
www.PaulRoark.com