Question about image sizes and printing...

[F-Stop]

Ok. I have a D80. When uploading an uncropped image to my lab, I don't get "4 green bars" on all of the images sizes, the "4 green bars" being quality of the print for that particular size. I usually get around 3 bars up to a 36x24. If I wanted to check print quality of a print would this work:

1. resize the image to 36x24
2. do a hardcrop withn that larger image with an 10x8 ratio
3. print that 10x8

If I'm thinking correctly, the 10x8 print would be a good way of telling the quality of the larger print?

I may not be making any sense. I have a hard time explaining myself sometimes. lol

 

[StewartR]

I think it would help - and I could certainly help you - if you thought in terms of pixels rather than inches. What are the pixel dimensions of an image straight out of your D80?

 

[pxl8]

It won't really help - the 10x8 print will have a higher PPI than the 36x24.

The 3 or 4 bars is based on the PPI of the image, if your image is 300ppi then it will decide the quality will be good but it's just based on the number of pixels. You could take a 900x600px image and re-size it to 36x24" (10800x7200px) and get 4 bars for quality but the print would still look rubbish.

Without re-sizing at 36x24" the print will be around 100ppi which isn't very high but when you view it from a sensible distance it will look fine. If you hold in front of your nose you'll probably notice the drop in quality but exactly the same thing can be said about giant bill board posters