-Very little is wasted, unlike the 7600/9600's which have long ink transports after the carts to deal with. It's basically like cleaning the heads each time. Change them often as you like.
-I put a piece of scotch tape on mine and hope for the best.
-This is a loaded question. There are two different ways of going about it. Either have Photoshop convert your images from your working space to the printer's profile, or let Epson's driver do this. The thing to avoid is a double conversion; don't make PS and the driver convert.
In the print dialog, under Color Management, select Document for Source Space. Then select your printer/paper profile in Print Space. Start with relative color and using blk point comp, to start with.
Hit Print.
In the next box, go to Color Management and select No Color Adjustment. Then make your other selections like paper type and dpi. Print.
This is my preferred method. It has PS making my color conversions and the driver doing no color work.
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