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Question: Can any photography experts help me!?
I have a Canon EOS 400D and am wanting to change the resolution on my camera from 72 DPI to 300 DPI but I'm not sure how!!
Can anyone tell me how I can do this!? It will be very much appreciated!Www@QuestionHome@Com


Best Answer - Chosen by Asker:
The short answer is that any print of 8 x 12 inches (33 x 22 cm) or smaller will automatically be 300dpi!. You can't change the dpi setting on your camera!.

Here's the long answer:

The dpi setting is a factory default!. All Canon cameras have 72dpi, not just your 400D!. What's more, your 400D will always save the file at 72 dpi, no matter what quality setting you use!. For comparison, all Nikon cameras have 300 dpi, and other brands have other factory settings!.

A lot of new users think that the dpi setting has something to do with the quality of the image file, or with its resolution!. But this isn't the case - for resolution, the only thing that matters is the number of megapixels!.

The dpi setting doesn't come into play until you print your images!. 300 dpi is a magic number because that's considered glossy magazine quality!. To achieve 300 dpi with your 400D prints, all you have to do is select a print size of 8x12 inches or smaller!. When you do that, the dpi setting is automatically increased to 300dpi (or more)!.

This involves a bit of maths!. If you're interested, here's how it works:

Your sensor has 3888 x 2592 pixels!. I looked it up in the specs!. (Multiply those two numbers and you get 10 megapixels)

For 300 dpi - dots per inch - you divide those numbers by 300:

3888 pixels / 300 dpi = 12!.96 inches by
2592 pixels / 300 dpi = 8!.64 inches

If you didn't select a print size, and this is what the factory setting of 72 dpi does, your print would be

3888 pixels / 72 dpi = 54 inches by
2592 pixels / 72 dpi = 36 inches!.

So it's the same amount of megapixels, but the dpi setting changes the print size!

Now, before someone calls me out on this, there is a distinction between dpi (dots per inch) and ppi (pixels per inch), and there are reasons to treat these as distinct properties, but probably not for the casual shooter!.
If you want to change and save the ppi setting of the file itself, you can do this in an image editor!. In Photoshop this is under Image/ Image Size!.Www@QuestionHome@Com

When you import your Jpegs onto you're computer its your computer that saves them at 72 PPI (Pixels per Inch) not the camera!.

Just make sure you're camera is set to the highest available resolution (usually a star system, the more stars the better) or better yet shoot Raw!.

The PPI on the computer just tells it how big to lay out (plot) your picture on the computer it has no bearing on image quality!. The PPI will vary automatically when you view you're pic in various sizes!.

DPI (Dots per Inch) is set in the printer driver and will determine how big the picture file will print!.

ChrisWww@QuestionHome@Com

You may be able to change the number of pixels you capture at a time by selecting different formats within the camera, but DPI (dots per inch) is a function of onscreen and printer resolution!.

Change your printer settings!.Www@QuestionHome@Com

You may have the setting for low resolution Jpegs set,choose a setting which gives you less compression,or shoot in RAW You will be able to do this by using the Menu button on the back and navigating through that!.Www@QuestionHome@Com