How large can I print?

thaKing

I have an older jpg that was resized to 5x7 (2500x3500, 500pixels/in), and I cannot find the original raw file. Now my wife is thinking she likes it so much she'd like to get it enlarged, maybe canvas. I know viewing distance comes into play, but realistically, if I wanted to print this on say 16x20, would it even look good?

Sam

It really does depend on the image quality, but with 3500 pixels on the long side you have a resolution of 175 PPI. This could work, especially on canvas. You could also uprez the image a small amount to say 240 PPI.

Take the image and size it to 16X20 and then take a 100% crop at say 8X10 and do a proof print. That will show you how the full size print will look.

Sam

thaKing

Ah, good suggestion - I'll try that. Thanks!

pathfinder

Canvas printing is a lot more forgiving of image detail, since the irregular canvas surface prevents detail from being displayed.

But the image still has to be sharp, with good contrast and lines.

I would suspect you could go as low as 125-150ppi, which is is in close agreement with Sam.


3500 pixels/150ppi = 23 inches in length, so it will probably be fine if your initial jpg is of a high quality.

mercphoto

Dude, you have 8.75 million pixels there. Pixel count is NOT your problem.[\b] I've gone 20x30 with that before with zero issues. All you need to be concerned about is how good looking is this JPG you have. I've done 16x20 with only 5 million pixels, done with a great lens, and the end print was fantastic.

arodney

I think you can safely send no less than 180 pixels per inch of data to most output devices and get decent results at viewing distance. That being the case, the current document would provide 19.4 inches along the long axis at 180ppi. Might as well use Image Size, turn OFF interpolation and set the size to 16 inches and let the new PPI values fall where it will (above 180 which is good). Proper file handling (capture and output sharpening) is always expected for best results.

pathfinder

Andrew, I agree with your value of 180 pip for most standard prints on paper.

But do you think the rough surface of a stretched canvas print really requires the same 180 ppi resolution, or could one use 125-150 ppi as I suggested?

arodney

Without knowing about the device, I can't say if less than 180 is OK. But the OP is pretty darn close at 175 over 20 inches.

thaKing

Shoot, forgot to check back on this...the quality of the jpg is superb! I was honestly thinking I would be ok with the file I have, but I've only ever printed when I had the uncropped original file. Everyone has provided great feedback, I appreciate it!