Need Print size advice

[stpierre87]

Quick rundown. A customer wants to buy two of my photos and have them Printed extremely large. The photos were taken on a Nikon D7000, In Raw, 14 Bit lossless compression. The customer is looking to have a print size of 40 x 60 and maybe have that printed on a gallary wrap. Is that even possible with the amount of megapixels the D7000 come with. Is the quality going to be any good. I don't want to say I can and order that print because someone has to pay for it even if its bad. I do use a Proffesional Print Shop and plan on asking them as well. ?????

 

[KmH]

At it's default setting your D7000 makes photos that have a 4928 x 3264 pixel resolution.

Some basic math shows that 4928 pixels divided by 60 inches = 82.13 pixels per inch (PPI) - assuming you didn't crop any and had your D7000 set to the Large, Fine quality setting.

Many of the good print labs protect their reputation by requiring a minimum of 100 PPI. So to print at 60 inches on the long side, the image resolution will have to be increased. 200 PPI will be a better target, however the desired PPI is image content and image quality dependent.

Note that increasing the resolution involves adding pixels (interpolation) that never actually existed. Some resolution increasing applications do that better than others. Check out software that uses fractal interpolation.

At any rate, with a bit of basic algebra we can derive another equation from the one above - 60 inches times 200 PPI = 12,000 pixels

FWIW it is convention to always state the width of an image first. A vertical/portrait image frame orientation would be called a 40x60, while a horizontal/landscape image frame orientation would be a 60x40.

40 x 60 is a 3:2 aspect ratio, as is your D7000's native resolution - 4928 x 3264 pixels.

There are some further issues - the gallery wrap and the canvas.

Figure a 1.5 inch wrap, so your photo really needs to be 43" x 63" to allow for the wrap. Canvas has a lot of texture that will kill some amount of image quality.
Prints can usually be sharpened more than images destined for electronic display, but again, image content and image quality are factors that determine how much, and what kind of, sharpening should be done.

For a gallery wrap that large I would recommend being sure museum grade canvas and stretcher materials are used.