I went hiking on Mount Hood in Oregon a few months ago and I got some pretty nice pictures. I left the house at 4:00 am to get to the trailhead before sunrise, but I was still a bit late. The best light was vanishing just as I got out of the car. Luckily I had a nice time anyway and the weather was fantastic. I also recently moved into a new house and had a large bare wall to fill. I decided to print my two favorite pictures from the hike at 20×30 inches.
To date, these are the largest prints I’ve ever ordered. I was a little concerned about stretching my A200’s 10 megapixels out that far, but it worked fine. I used Lightroom to do the resizing and upsampled to reach 300 dpi. That’s 6000×9000 pixels or 54 megapixels. Keep in mind that upsampling an image in this way will not add any data, but it will prevent square pixels from being visible if anyone touches their nose to the glass. Printing at this size stresses the lens and sensor in ways that an 8×10 doesn’t even come close to. After trying this experiment, I’d say 20×30 is probably the biggest you can reasonable print from a 10 megapixel sensor. The results look great and you can only see the pixel deficiency if you really get close and squint.
If you have a picture that you really like, I’d strongly recommend printing it large. Print it one or two sizes bigger than you think you should. Resize the image to at least 200 dpi if you need to and be sure to pay careful attention to sharpening. Oversharpening is the norm on the web, but on a huge print those ugly halos can really stand out.
What I like about large prints is that you can show a picture that has subtler qualities where an 8×10 has to work harder to grab your attention. I also like that printing large is a great way to see all of those efforts put into sharpness and image quality finally pay off. Here’s a shot of the two prints in their new home: