Image Print Question

[MacUser2]

I made a close-up image that is 6000 pixels wide by 4500 pixels high, my daughter wants to make an 10” x 8” print out the image, along with some of my other alstroemeria pics, and hang them in her office.

The resolution of the resulting image would be about 600 ppi (more than is needed for a high quality print).

This is a screen grab of the "fit on the screen size" image (about 67%)



Now is is the question, when I view the image on my screen it looks superb at the “fit on the screen size”; about 67%. However, when viewed at 100% on the screen, I can see some evidence of “Halos” creeping in. The halos become more visible at 200%, but still not too bad,

It is tedious, but I can remove the halos. However, she doesn’t want me to go to the effort.

I assume that the lab will automatically print the image at 300 psi, Since the native pixel density of the image is twice what the lab will print the image, what will happen to the halos, will they vanish or should I go to the extra effort of removing them.

As an option, should I only send her screen grab or should I send her the 100% highest quality images and hope the lab will do the right thing?

 

[Lester Lefkowitz]

Let's assume you have a typical 24" monitor that's 1920 x 1080 pixels (1920 in the horizontal direction). You say you don't see any halos looking at the full image. If you don't see them on a 24" monitor, you will definitely not see them on a 10"-wide print.

Viewing at 100%, you are look at a portion of those 6000 camera pixels. For an 10x8" print printed at the usual 300 dpi, that's 6000 divided by 300, so you are looking on your monitor at the equivalent of a 20"-wide print, with your nose up close to the print.

No matter how many pixels you send to a lab - too many or not enough - they can always make a print any size you want; the interpolation from the pixels in the image file to what is necessary for the printer is a very basic part of any print-making program.

My earliest "professional" digital camera was 12 megapixels, about 4,000 pixels wide. Printing at 300 dpi, one would assume 4000 divided by 300 would "only" allow for a 13.3"-wide print. By I have made 30"-wide prints from "only" 4,000 pixels and they look just fine.

Lester Lefkowitz, author of The Manual of Close-UP and Macro Photography, Volumes I & II

www.MacroPhotographer.net

 

[MacUser2]

Thank you, Lester

 

[Velvetworm]

Perceived detail of a print is also influenced by viewing distance. Unless people are going to pixel-peep these printed images hanging on the wall, then it’s unlikely they will be able to see such detail.



I was at an art exhibition recently and the artist had made massive (maybe 3m x 3m) prints of various photographs. From the “naturally viewing distance in the gallery they looked sharp as a tack. I went right up close just to see and sure enough they did not look at all sharp. But I guess the point is it didn’t matter as no one is viewing it from 30cm away.