The print driver is set for 600 dpi. I see no difference in the white square problem whether the Q reported PPI is 500 or well over a 1000. And I would expect no difference in driver issues because Q is resampling to 600 dpi regardless of source image pixel count.

But I am confused about ICC. If I set "Let Printer manage color", then I get some minor dithering artifacts in part of the printout. If I choose an sRGB ICC for the printer, I get very consistent print quality throughout the image. What does "Let Printer manage color" do? Does it change a driver setting that I have no access to? I see that in the HP driver settings I can set Color Management to either "Color Smart/sRGB" or "Adobe RGB 1998". Does the Q setting of "Let Printer manage color" enable use of one of the driver color management settings? And if an ICC profile is used in Q, are all the color management functions in the print driver disabled?

I really like the "Show preview before printing" option in the HP Driver. I tried various combinations and could see the white squares and other artifacts in the preview without wasting any ink.

Bottom line is that when I set "HP Real Life Technologies" RTL photo fix to off, the problems go away. Full RLT photo fix can make the prints look nice, but I suppose with the right amount of sharpening etc. in Qimage, I should turn RLT off. And I recall reading recommendations like that in the Q manual a long time ago. Thanks for the advice.

Another interesting fact is that when I select "Show Preview before printing" in the printer setup properties, the HP software displays an image before sending it to the printer. This image also has the whites squares (different each time) as seen in the attached screen capture.

Thanks for the info. I have a Windows 7 64 bit machine which is fairly powerful.

I tried the Print Format Raw as you suggested. It causes a paper jam every time. When I print a 4x6 in the EMF format the printer status dialog shows 24.7 MBytes being printed. When I print in the Raw format, the dialog shows 1.69 KBytes. I am printing just one 4x6, so I don't think the page spooling matters.

I occasionally get white squares in my 4x6 prints on an HP C7280. It seems to be random but may be related to borderless mode. I've had this problem for over a year. I tried wireless and Ethernet cable connections to the printer with the same result. I can print the same print 5 times and see the white squares in different places each time. I just printed 21 small images on a 4x6 and when the white squares show up, they are one quarter of one or more of the 21 small images. I once had a white square on a single 4x6 image, but the floating text printed over the white square.

Where is this coming from: Qimage, the driver or the printer?

See attached.

I use Studio on a few different computers at home. Can I do the same with a single purchase of Ultimate?

Thanks for the offer, Fred. I'll do that tonight.
Ken

Thanks, but I have checked and I am selecting an appropriate area. It seems like there is something wrong when using the ~5 MPix size raw files.
Ken

I've used RAW processing on the large size files and it works fine. But I recenetly shot a bunch of images using sRAW2. This is the small size raw. I cannot get white balance to work at all using Refine Raw Exposure. I always get a strong purple hue. I tried it with and without the icc profile I purchased from ddisoftware.

The eye dropper white balance in the batch filter works fine.