Sorry, ANOTHER Megapixel Thread (Printing and Megapixels)

Started Aug 1, 2014 | Discussions thread
skyglider Veteran Member • Posts: 4,583
Re: Sorry, ANOTHER Megapixel Thread (Printing and Megapixels)

JayWhyOkay wrote:

I'm aware that megapixel counts don't really offer much in terms of digital and screen viewing. Somewhere around the 8MP count is pretty much the ball park at least, or something like that. But that's not really the point of this thread. I'm concerned about the relationship to megapixels and printing.
I've never really gone deep into printing photos, but I heard for small prints that it kind of reflects the digital viewing. However, I wanted to know this: for small prints (maximum size would be something like 4in x 6in), does the same logic apply to small prints? Would there be a good difference between a 12 MP, 16 MP, and 24 MP picture in terms of printing? Or would it just be negligible and be one of those cases where it just increases the resolution? These prints are going to a local scrapbook competition, so quality is a bit more of the concern here (and yes, a good printer would also matter in this case, but don't worry about that).
I want to know what you guys have to say about this. Is 24 megapixels in small prints just unnecessary? Would a higher concentration in pixels actually reduce the print quality? Sorry, but I'm not really the printing guy.

Jay,

The way to calculate the MP required for optimum prints is to use pixel resolutions.

As another poster said, 300 dpi (dots per inch) is the industry standard for optimum print quality. Places like Costco, Walgreens, Walmart, CVS and other mainstream print labs all use 300 dpi for their prints. (I verified this a long time ago by visiting them or calling them up.)

Knowing this, it's easy to calculate the pixel resolutions of your images for the different print sizes.

4 x 6 inch prints: (4" x 300 dpi = 1200 dots) (6" x 300 dpi = 1800 dots) So your image needs to be 1200 x 1800 pixels or larger. Larger is OK since the print lab will resize down to 1200 x 1800 pixels before printing. ... Note that 1200 x 1800 = 2.16 MP.

5 x 7 inch prints: 1500 x 2100 pixels = 3.15 MP

8 x 10 inch prints: 2400 x 3000 pixels = 7.2 MP

So a 7.2 MP camera can produce images for 8 x 10 inch prints or smaller.

But it's good to have more MP to allow cropping of the image since every picture will not be perfectly composed. So a 12 MP camera will do very nicely for 8 x 10 inch prints.

Do the math for larger print sizes.

Also note that modern resize algorithms are very good. So it's possible to take an image from a 7.2 MP camera and make a print larger than 8 x 10 inches and still have the print look quite good.

Here's a wikipedia link that has standard print sizes with the image resolutions for optimum print quality:

http://en.wikipedia.org/wiki/Photo_print_sizes

Sky

Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow