How to resize your photo for printing and other tips

[satans worm]

So i have some pictures taken on a Canon EOS6D at 20MP that i want to print at 20X30 inches (at Costco)

Whilst i know i need something like a 50mp camera to do this natively at 300DPI, how is it best to do it with what i have?

As i understand it i can resize the photo via Photoshop , are there other better alternatives that would give a sharper result?

Should i aim for 150DPI or make it resize to the full 300DPI?

What else should i do on export, ie sharping etc?

Ive never actually printed before, and this is for a friend who wants one of my New York Photos that i have taken

Any advise gladly taken, note i am in the US so any local or UK based printing alternatives wont work for me,

Thanks

[C n C]

When I've been getting high quality prints made in the past, I've talked to the printing company to determine exactly what models of printers they are using, and most importantly, what the native resolution is - don't assume 300 DPI, as quite often it may be 240DPI, or another similar value.

Once I've determined the DPI of the printing machine, I've then used Photoshop to re-size the image to the size of print I want (20x30 inches, or A3 or whatever), at the native resolution of the printing machine, then submitted the (very large) image to the printing company.

I also generally sort out the colour on a calibrated monitor, in a colour space that is supported by the printer. Whilst some may go for Adobe RGB, quite often SRGB will provide excellent results. Whatever colour space you use, it's important to specify that the printing company use the embedded colour space, and don't start trying to apply colour correction to "improve" your image - you want it as you've edited it.

[Simpo Two]

I would just order a 30" x 20" print. As long as image aspect ratio is also 3:2, it will work.

[S1bs]

Exactly what the above poster says - just send them the JPG file cropped to the correct ratio - Don't worry about what the DPI is.

Although it can be important for some things, in general photo printing the DPI is just a nominal measure of size. A 24mp file at 72DPI is exactly the same image quality as a 24mp file at 300DPI.

(You could actually upsize a 24mp 72DPI file, in something like Photoshop, when changing it to 300DPI and increase it's actual file size but you are mostly just duplicating pixels and the actual increase in quality is pretty small although the algorithms for creating the new pixels are improving over time)

So long as you haven't already massively cropped the image that you want to print, a 6D file should look good at 30x20.

Hope this helps.

Edited by S1bs on Saturday 28th August 20:51