How can you tell?

Kyna · Jan 12, 2011

How can you KNOW if your edited photo will be good for print? I have seen and been told to crop in on a photo. Which then increases the pixel size right? So....after cropping in how can you tell if the photo will print nicely as an 8x10 or larger?

Thanks!

Robin Usagani · Jan 12, 2011

multiply the inch by at least 200, 300 is best. So if you have 10" then you need at least 2000 pixels wide.

KmH · Jan 12, 2011

Kyna said:
How can you KNOW if your edited photo will be good for print? I have seen and been told to crop in on a photo. Which then increases the pixel size right? So....after cropping in how can you tell if the photo will print nicely as an 8x10 or larger?

Thanks!

The native resolution of your Canon XS is 3888 pixels by 2592 pixels.

If you don't crop any of those pixels away, and you print with 100 pixels-per-inch (ppi) the photo would be - 38.88 inches by 25.92 inches.

At 200 pixels-per-inch a print would be 3888 px divided by 200 ppi = 19.44 inches wide and 2592 px divided by 200 ppi = 12.96 inches wide.

At 300 ppi it would be 3888px / 300 ppi = 12.96" by 2592px / 300ppi = 8.64". (exactly 8"x12" would be at 325 ppi)

One of the popular online consumer photolabs Mpix.com, has printers that don't print at more than 250 ppi, and they have RIP software that does the ppi calculations for you. You just upload your image making sure there is enough cropping room for the various aspect ratios.

Here is the Mpix.com tutorial page for How To Prepare Your Images for printing: Mpix.com - Help. Note: Mpix stakes their reputation on a 100 ppi minimum pixels-per-inch size.

Here is where people get goofed up, and it called the aspect ratio. In round numbers your XS makes 8x12's not 8x10's. 8x10's are a differently shaped rectangle than the 8x12 your camera natively makes.

So to take a photo and then get it printed as an 8x10 you're going to have to crop 2 inches off the long side of the photo anyway. Often people didn't leave room in the viewfinder to crop those 2 inches away.

8x10's have an aspect ratio of 5:4. The long side is 5 units long and the short side is 4 units long.

8x12's have a 3:2 aspect ratio. The long side is 3 units long and the short side is 2 units long.

5x7's have a 7:5 aspect ratio. The long side is 7 units long and the short side is 5 units long.

Here is a graphic I made that shows what those aspect ratios would look like in a viewfinder:

Here is a chart I made you might find handy: