Size for printing A3 and A4 images

[moosehunter]

Hi
Can some one tell me what is the minimum size and DPI
for printing A3 and A4 images from a digital camera,
With Kind Regards
Dimitris
( MooseHunter )

[Kyuss]

A4-A3 printing

Printing is normally done at 300DPI. So for A4, you need about 3600x2400 pixels. A 6MP camera like the D60, 10D, 300D or D100 can make very nice A4 prints (a little resizing needed). A3 I have never tried. It can't be that bad...

Cheers

[moosehunter]

Thank you for that .
Dimitris

[JeffinDEN]

Re: A4-A3 printing

Printing is normally done at 300DPI.

Cheers

Not always. Check the DPI requirements of the device you are printing to. Many times if you are gonna spew ink at a 300 dpi image you are just wasting it. Many printers like the Epson 1280, 2000, 2200, etc. will print better with an image re-sized to 150 dpi, keeping the output dimensions at A3 or A4.

Image resolution and printer resolution are not one in the same.

[ckw]

300 DPI is almost certainly not the best output for an inkjet, though it is the normal standard for publication (based on @150 lines per inch needed for quality offset printing).

What is the best output for an inkjet is a matter of some debate amongst the experts. Apparently the "native" resolution of an Epson inkjet is 720 dpi (ignore what it says on the box) which is based on the actual nozzle array. Sending anything to the printer other than 720 dpi means that the printer driver has to do some interpolation, with the risk of loss of quality.

Given that sending 720 dpi to the printer is impractical for most of us, another school of thought suggests that the next best thing to do is use an exact fraction of the native resolution (eg. 360, 240, 180 dpi) as this makes life easy for the print driver and should result in finer detail.

Having said that, online print services (using different technologies) can achieve stunning results with remarkably low dpi - I've had posters made with effective dpi's as low as 100 ... mind you, you tend not to examine posters from a distance of 3 inches .

Me, I print on an Epson from 10D/D60 files. Printing at 240dpi gives me good (sellable!) results at A4 with a little margin to spare for cropping. When I need to go larger (or use a tighter crop) I have 2 choices - either drop the resolution to 180dpi or upsize the image. Frankly I don't see an enormous difference in either approach, though I tend to favour careful upsizing (using stair interpolation) on the PC simply because by sticking with the same printing parameters I figure I've got more chance of acheiving consistent results.

Cheers,

Colin

[Skymonster]

I assume we're really talking Pixels Per Inch (PPI) here... Dots Per Inch (DPI) is totally unrelated to image size / resolution and is just a measure of the density of the ink a printer can lay down on a page.

Andy

[ckw]

Yes Andy you're right about PPI, but I think the question here is about DPI - ie what density do you need to send to the printer, the point being that any given pixel dimensions could be printed at a whole range of sizes depending on the selected DPI.

I read the question as "what DPI do I need to send to the printer?"

Cheers,

Colin

[moosehunter]

Hi
Thanks for all your help the printer i am using is the Epson 1290
With Kind Regards
Dimitris
( MooseHunter )

[Kyuss]

Hi,
When I mentioned "printing is normally done at 300 DPI (ppi)", I meant the printing at a photo lab. I take it that they do the resizing (or ajusting PPI? dunno, resizing seems easier...) when a customer does not provide the right picture size. I don't have a printer at home, so I won't make any comments on that!
Cheers...

[CPH Aviation]

I've made some very nice prints in A4 format. The pictures was in 72dpi and taken with a digital camera at 4.1MP. They were printet out on a HP3820 printer on photopaper.