Printing - How Often and What Size?

[Kayaker72]

How would you make a 30 x 40 with a 20 MP camera and have it look good?

Dave

I would mount the image on a wall behind a table so people can't get too close. Then keep other images that are 300 dpi relatively far away.



I am actually fairly serious. While this is debated at great length, it is really is pretty subjective. I've heard some people go as low as 75 ppi, and that computer monitors are often 72 ppi (except for special Apple people with their Retina displays ). My monitor is right around your 121 ppi and I am viewing it from ~2 ft away. Doing the math on a $2,000, 4K, 31.5" photo editor monitor and it is ~140 ppi.

But, for printing, I've seen different people state the human eye starts to resolve differences at 75 ppi, 150 ppi....then, from a discussion about a month ago, I saw a reference to where someone set up samples of 300 to 600 ppi and claimed that anyone he's had look at them can see the difference.

But, is what the human eye can differentiate even the point? Or is it more of how the print will look in a particular setting. And that gets down viewing distance.

So, how far back are people going to be? 5-10 ft, I have a hard time thinking 121 ppi is an issue. If closer, or if this is for a client that will look at it closely as they take it out of a box before mounting it, then interpolating will not give you additional detail, but it may provide a better viewing experience. I would probably interpolate until you have an image that is ~>200 dpi, maybe even 300 dpi. But, that is just about smoothness if someone gets really close.

[Jonathan Huyer]

I would mount the image on a wall behind a table so people can't get too close.

That's exactly right! A lot of images can be blown up quite large, if they are meant to be viewed from a bit of a distance. I made a 6-foot wide print of an owl, from a 20 MP image that was cropped to about 10 MP, and I have to say it came out great. If you look at it right up close, of course it's a bit fuzzy, but you can't appreciate the image unless you're standing back so it really doesn't matter. On the other hand, a friend of mine who is a pro has a spectacular landscape shot that has all kinds of detail in it. It's meant to be appreciated both from a distance and also from up close, so it needs incredible resolution. He shot it with a medium format body (I'm guessing 50 MP), so he can blow it up to 8' wide and it's still absolutely tack.