print resolutions

stcstc

I thought i would make a useful little card, I am going to have them printed as postcards. but for now i have put it on my website

its a pdf with a table of common photo sizes and pixel resolutions required at various pixel per inch

anyway, its here

print res


please let me know if you find it useful, and also if you see anything either wrong or what would you like to see be added

Thirdfox

I thought 300 was the highest the human can distinguish? Can you see a clear difference at 360 dpi too?

And I guess 180 would be your recommended "minimum" for prints that will be subjected to close-ish inspection?

oshead

Thanks steve. I guess it's handy as a quick reference and also for those who don't have photoshop.

stcstc

the reason i use 360 is its the native resolution of epson printers, if you give them a 300, they do interpolation, and at bigger sizes it can be noticeable

Ricky91t

What's the original ppi of a photo?I thought it was 72dpi?Whats that in PPI? :eek:

stcstc

ah ok

ppi is pixels per inch - this is the number of pixels per inch in your digital file

dpi is the dots per inch, number of dots printed per inch by the printer


you should supply files to your printer ideally at the native resolution of the printers, so for my epsons its 3600 ppi, for canon and hp its 300

hope that helps

Cameraman

Ricky91t wrote: »

What's the original ppi of a photo?I thought it was 72dpi?Whats that in PPI? :eek:

A photo doesn't have a PPI/DPI as such.
It only has a resolution in pixels e.g. 1024 x 768.
So if you have a photo straight from camera that is say 3000 x 2000 and open it in your editing software, then any PPI/DPI value displayed is purely arbitrary, and has no relationship to the actual original image.

However, when you come to print it, that's when the DPI value comes in - and where Steve's table comes into play.

Thirdfox

Ah, I see. I'm very much a greenhorn when it comes to the realm of printing, thanks for clearing that up.

PaulieC

Nice one Steve. One thing before you print off 1000's of them, dimensions is spelled wrong - Dimesions

stcstc

doh


i cant spell for toffee

Cameraman

cambo_gueno wrote: »

Nice one Steve. One thing before you print off 1000's of them, dimensions is spelled wrong - Dimesions

And so are canvas and acrylic

PaulieC

Cameraman wrote: »

And so are canvas and acrylic

doh!

I can't proofread for toffee

stcstc

hey everyone

I have printed a whole bunch of these as postcards

anyone who wants one, send me your details and will send one to ya

emul

Suggest you look at spelling again.

Dimension was spelt correctly 1st time.

Sorry Steve, hope you can cancel print job

stcstc

ah its right on the cards, its just on the pdf, which i just havent got round to changing yet

wersal gummage

just looking at that PDF.

so, ideally you'd want a 3660x2880 resolution picture just to print a 10x8 print ??

i have a picture here i want to print up, its 4700x3200 resolution (approx) - its an 18mb file and taken with a 15mp camera.

i was thinking of getting it maybe printed at 24x20.... according to your site i'd need double my resolution for that to print up well ????? how on earth does one take a photo with that kind of file size ?? does the 5dmk2 even produce 8500x7200 resolution photos ??

Adriatic

Say if I was printing a 10x8, I should resize an image to that resolution before printing if it is over that resolution and if it is under that also?

stcstc

well it kind of depends on a few factors

size, resolution, the image, what paper its being on printed on


for example i have a sample acrylic mounted print which was shot with my 30d, it upscaled it to 24*20 and it looks fine, 99.99% of people wouldnt be able to see the scaling


a good example is i printed to canvaes recently for a client, they were 38" on the short side, so around 55 on the long


one of them was a 1Mb jpg image, now its no work of art, but stood away from it, it did look very good

so what it says in the pdf, is in the IDEAL world, you should always try printing at the native resolution of the printer, and the best practice would be to do the scaling in photoshop, rather than allowing the print driver to do it for you.


if you dont print at the native resolution, the print driver does scaling anyway