Printing photos

[pjay]

hey you, wonderful people!
I'm here with yet another question... I want to print a photo I've taken with my 6D (dont know if that matters) a 20,2 mp camera and the photo is 5472 x 3648. What is the biggest possible print size I can go for? Would that photo size go for 60 inch (150cm) wide photo? Do i get the answer by just converting pixels to inch or cm? Or how do I know whats the biggest size i can go for?
Thank you guys sooo much for your time!

 

[DustinB]

There's a recent thread where this was discussed in detail: printing | Photography Forum

There are many factors to it, mainly typical viewing distance etc...

 

[Ido]

It isn't as simple as converting pixels to inches, though dividing the pixel dimensions of the image by the pixel density in print (240, 300 and 360 pixels per inch are most common) will give you predictably good results more often than not.
That means that if you choose to print at 240 ppi, the print size will be 22.8 x 15.2 inches.

Typically you can print bigger than that. You can enlarge the image in various ways, but Lightroom makes it very easy. Upon export, choose to resize the photo to certain dimensions in inches or cm, and make sure you choose the desired print resolution (pixels per inch). It's also good practice to sharpen the image for print - another thing that's very simple to do in Lightroom's export dialog; just choose the media (matte or glossy paper), set it to Standard and you're all set. If it looks too sharp, set it to Low and try again. If it isn't as sharp as you'd like, set it to High and try again.

Viewing distance should also be taken into account. The bigger the print, the farther away it will be viewed from, thus resolution isn't as critical anymore.

 

[Big Mike]

You can print as large as you can afford. Have you ever seen a photo on a billboard? Do you think they take those photos with 1000 megapixel cameras? (they don't).

Of course, the resolution of the print will be lower when you print bigger, but that is usually made up by viewing the print from further away. If you looked at a billboard up close, it looks terrible...but from 50 feet away, it looks just fine.

The same is usually true for wall sized prints. You aren't supposed to view a 100cm print from 30cm away. Stand back to about 1.5m and you probably won't notice the lack of resolution.

That being said, there are a few rules of thumb. For smaller prints, which will be viewed up close, we usually want 300 pixels per linear inch of print. So a 4x6 print would want a file that is at least 1800x1200 pixels.

Some people say that 240 Pixels Per Inch (PPI) is enough. And as your print size gets larger, it's easier to get away with lower PPI values. 150, 100 etc.

Some labs have a minimum value of 100 PPI.

We also have to consider that the pixel size of the file can be changed. You can use software to enlarge (add pixels) to the image. This will require some interpolation, which will inevitably lower the quality, but you can significantly increase the size of the image before it becomes too bad.

And in the end, it really comes down to your own expectations. The best way to really understand print quality and size, is to go ahead and have prints made and see for yourself.