Hi Beverley

DPI relates to printing and not digital capture. DPI actually refers to <u>printer</u> dots per inch. Even though your camera says 72dpi, that doesn’t really mean anything. The important thing is the pixel size, which i think on your Pentax is 4288 x 2428, that determines the size you can naturally print at. To get the best quality you have to set the camera to it’s largest setting, this will give you the maximum resolution for your camera. I assume you won’t want to shoot in RAW (as that needs more post processing) so set it at the Highest JPEG you can. I used to have a 12MB camera and took great photos with it that were enlarged quite a lot and still look good (although I only shot in RAW).  The important thing is to keep your ISO as low as possible so you aren’t introducing any ‘noise’ (which is like grain) into your image and to make sure it is not underexposed as that also gives issues when making large prints.

What size are you hoping to print at?  I just found this info on your Pentax camera which may help. Are you taking photos for inventory purposes or so you can make Giclee (or similar) prints to sell?

<b>Print Quality</b>
<i>ISO 100 to 400 images look great at 20×30 inches</i>

ISO 100 to 200 shots look great at 20×30 inches, with excellent detail and color.

And I just found this explanation on the internet for you which probably explains it better than I can!

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I’m going to offer my explanation from the print-industry POV:

1) Images captured via a digital camera are usually 72ppi. If you bring this image into a post-processing program without changing its values, it will remain as a 72ppi image, and the physical size is huge (eg: an image from the K10D is 136.03cm x 90.88cm. That’s over a metre wide).

2) For professional printing purposes, an image being prepared for print should be no less than 300ppi in resolution if pristine image quality is to be preserved.

Effectively, this means if you were to “squash” a uncropped K10D image so that it contained 300 pixels to every physical inch (300ppi), the actual size of the image would be about 32cm x 21.6cm.

From a practical point of view, this means that your photograph won’t lose any evident image quality provided its print-output size doesn’t much exceed the size of an A4 sheet of paper.

In reality, loss of image quality is not usually evident to the naked eye(unless you’re looking really hard) until print-resolution has dipped below about 200ppi. So you could get away with printing an image from the K10D to a physical size of about 50cm x 33cm (larger than an A3 sheet).

However, if you were to print the image at its unaltered onscreen size (136.03cm x 90.88cm) it would be printing at its original resolution of 72ppi, and of course the image quality would suck!

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I hope that has made sense and hasn’t confused you further!  However if your Lumix takes great shots, that may be an easier one to start with.