Increasing DPI in PS

Mon Jan 26, 2009 4:56 pm Author: Paul Humble

I feel a bit sill asking this but I never use Photoshop so thats my excuse!!

I have a file that im trying to send to a third party printer but they need it at 300dpi and at the minute its only 144dpi.

How do I change this?

Mon Jan 26, 2009 5:12 pm Author: Martin Grimmer

Paul,

go to image/image size and change dpi to 300 there.

martin

Mon Jan 26, 2009 5:16 pm Author: Jeremy Howes

To actually change it to 300 ppi you will need to change the image size to 100% then 300 ppi.

Jeremy

Mon Jan 26, 2009 5:25 pm Author: Paul Humble

cheers guys

Mon Jan 26, 2009 6:05 pm Author: John Childs

Martin-G wrote:go to image/image size and change dpi to 300 there.n

That's not going to work.

I had a big row with a designer, who thought that because he saved the poxy 72dpi image he'd downloaded from the internet at 300dpi, it would improve the resolution of the final print.

If you start with a 144dpi image, you can save it at a million dpi, but there is no more information in that than in the original.

Mon Jan 26, 2009 6:11 pm Author: Martin Grimmer

John - agree with you if you are referring to the quality - but didn't think that was the question.

Martin

Mon Jan 26, 2009 6:12 pm Author: Paul Humble

Cheers for all the help, the quality was fine at 144dpi as it was just a basic flyer, but I think the 3rd party uses an automated file check system that boots out anything under 300dpi.

Mon Jan 26, 2009 6:20 pm Author: Jeremy Howes

Hi John,
The question was not about how to improve the quality but how to change the ppi (dpi) which you do by changing the 'Pixel Dimensions' to 100 % the the 'Document Size' to 300 ppi.

Jeremy

Mon Jan 26, 2009 6:40 pm Author: Owen Lees

Not exactly...

http://www.tildefrugal.net/photo/dpi.php

Oo

Mon Jan 26, 2009 7:27 pm Author: Jeremy Howes

How would you do it Owen?

Jeremy

Mon Jan 26, 2009 7:35 pm Author: Owen Lees

Sorry I wasn't offering an opinion on the technique as you are correct in that you simply ensure that the image is 100% and then 300 dpi (the natural result being less stress on the image) - I was just pointing out that ppi is a little different to dpi (just in case anyone was getting confused).

Ok ok its anal I know!

Oo

Mon Jan 26, 2009 7:42 pm Author: John Childs

Jeremy Howes wrote:The question was not about how to improve the quality but how to change the ppi (dpi)

Hi Jeremy.

Yes, you're right. I just couldn't see any good reason why anyone would want to turn a 144 dpi image into a 300 one if it wasn't going to make any difference other than to raise the file size.

Owen, I can't see anything in that document that contradicts what I said. In fact it specifically says not to throw pixels away if you might need them again. Can you explain please?

Mon Jan 26, 2009 7:49 pm Author: Owen Lees

John Childs wrote:
Jeremy Howes wrote:Owen, I can't see anything in that document that contradicts what I said. In fact it specifically says not to throw pixels away if you might need them again. Can you explain please?

Hi John.

I think my post has been completely misunderstood. I am not arguing with the technique AT ALL.

I am merely pointing out that there's a difference between ppi and dpi for those that didn't know and may have wanted the knowledge.

Tell you what I'll simply keep my mouth shut in future.

Oo

Mon Jan 26, 2009 8:01 pm Author: Jeremy Howes

Hi John,
As a standard I always, unless images specified over 300 ppi, change the size of incoming client images to 300 ppi, this keeps it simpler and uniform when creating multi image artwork.

ppi when creating dpi when printing.

Regards
Jeremy

Mon Jan 26, 2009 8:30 pm Author: John Childs

Owen Lees wrote:I am merely pointing out that there's a difference between ppi and dpi for those that didn't know and may have wanted the knowledge.

Fair enough.

Mon Jan 26, 2009 8:52 pm Author: DavidRogers

John Childs wrote:...Yes, you're right. I just couldn't see any good reason why anyone would want to turn a 144 dpi image into a 300 one if it wasn't going to make any difference other than to raise the file size...

But it does if you don't simply increase the dpi - but re-sample and re-interpolate the image using a smart filter such as that used with PS.

I've been supplied utter garbage by customers as low res images and re-sampled them at full size, full res and the results CAN be a huge improvement over simply printing the original as the software uses 'best guess' algorithms to fill in the extra detail based on the neighbouring pixels. It's not just the case of breaking the existing pixels to smaller blocks...which would be pointless.

Dave

Mon Jan 26, 2009 10:15 pm Author: Steve Underhill

Of course you can also print the original and scan it back at a higher resolution, that works.
What photoshop does by increasing dpi is add pixel data, but as mentioned effects what size output you want so a 300dpi a4 pic will be 150dpi at A3 etc its pixels per inch that has to be increased not just the dpi.
that came from a print house in London when I didnt understand it either.

Mon Jan 26, 2009 10:24 pm Author: Paul Humble

Im so glad I dont need to use Photoshop that often!! lol

I sent the new resaved file off just before I went home, so ill see tomorrow if its been accepted.

Mon Jan 26, 2009 10:28 pm Author: Steve Underhill

Photoshop is something I could not live without, been using it over 10 years now and if photoshop cant do it then it cant be done as far as an image is concerned in my opinion.
Look at all those unblemished supermodels in vogue and cosmo, then see them stepping out of the door to get the milk, yep photoshop did that.

Mon Jan 26, 2009 10:31 pm Author: Paul Humble

Steve Underhill wrote:Photoshop is something I could not live without, been using it over 10 years now and if photoshop cant do it then it cant be done as far as an image is concerned in my opinion.
Look at all those unblemished supermodels in vogue and cosmo, then see them stepping out of the door to get the milk, yep photoshop did that.

Are you suggesting Kerry Katona has always been rough? :lol1:

Mon Jan 26, 2009 10:40 pm Author: Steve Underhill

Thats the type of thing I am definetely suggesting, Kylie is fat, posh spice is invisible except a few ribs, and Helena Christiensen is actually another life form.
Photoshop saves the day for these people.

Increasing DPI in PS

Increasing DPI in PS

Who is online