HP ENVY 7855 prints fine to letter size but not photo paper.

[WAH99]

Trying to print photos from my phone to HP ENVY Photo 7855... brand new ink cartridges installed (& calibrated).  Same picture prints fine to letter size paper.

it will attempt to print the photo size but the image/ink quality is awful

[TEJ1602]

@WAH99, Welcome to HP Support Community!

I see that you have issues with printing photos, let us try to isolate and resolve the issue. 

Ensure you are using the supported paper type and size to print photos. Refer to the document  Product Specifications for the HP ENVY Photo 7800 All-in-One Printer (Y0G50B) for details.

Also, before sending the print job, ensure you select the right paper type and size from the device you're trying to print from. 

I am not sure if you're using HP Smart or AirPrint, so here I attach the documents for help with changing the paper settings-

HP Printers - Printing from an iPhone, iPad, or iPod Touch

HP Printers - Install and Use the HP Smart App

Hope this helps! Keep me posted. 

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