dpi

i just bought a pentax k100d because i needed a camera capable of 300dpi.

when i open my images in photoshop they say 72dpi but my camera settings are on

best.

am i doing something wrong or can i just change the dpi in photoshop without

loss of quality?

In answer to your second question - yes you can change it in photoshop without loss of

quality as long as the 'resample' box isn't ticked.

 

It doesn't matter though, really - you can set it to whatever you like.

When you adjust the dpi in PS you will notice that it is related to the size of the print. Dpi is the density of the pixels for a given print size. If you keep the number of pixels the same (by NOT checking the Resampling box, as mentioned above), then the dpi goes up as the print size goes down. So go ahead and change it to 300 in the dpi box, but you will notice that the dimensions will decrease. Any camera can produce 300 dpi, the question is how big will it print at that density. By the way, you can also get very nice prints from that camera at much less than 300 dpi if you want to go bigger. The 72 dpi you see is a random default number that PS uses.

excellent, thanks alot.

really it doesn't matter if having prints professionally made.

 

The RIP on a printer, which is generally more advanced than anything you have at home calculates the DPI based on image size for optimal printing.

 

Really all that matters is your pixel count.

 

For printing at home aim for slightly more dpi as inkjets seem to require more dpi (and pixels) to print optimally.

 

For what it's worth, I'm not quite sure why you are aiming for 300dpi with a digital camera. 300 was a general rule for film scans because apples are not comparable to squid.

 

With digital you generally need closer to 200dpi for handheld shots, and a general rule is 100 pixels per inch for printing using continuous tone sources.

 

I always ask the printer what dpi they prefer to eliminate wasted image size. So I'll size my image to slightly larger bleed but at the DPI they specify.

 

so if you have 6MP camera, tripod mounted it, and used a decent lens, got a good exposure in good light. You should have no problems printing to 20x30 in (2000x3000 pixels).

 

I've personally printed 11x14 and 12x18 using the ist D with no problems. This is of course as big as I really care to print other than a few stichted panos which are 20x30 in size.