DPI and Enlargements

[AJA Photography UK]

Hi there folks, I hope you can answer some questions for me. I have some Wedding photos that I took in 2009 and want to get some printed and make a portfolio up to show a couple whom I am taking there wedding photos for.

At the time I took the photos in 2009, I was using a FujiFilm FinePix S8000fd. Most of the photos are 3264 X 2448 @ 72dpi my questions are:

1. what reasonable size can I enlarge to without distorting the photo

2. If I was to Edit the photos to a differant size Can I also adjust the dpi with out hurting the photo.

Hopefully that will answer some of the questions going round in my head at the moment

 

[artyman]

Ideally printing at 300dpi is the usual target though 200dpi will still give pretty good results, so you could get an 11"x 8" or 16" x 12" print from 3264x2448. Some fractal programs can resize without loss of quality.

 

[hollis_f]

Can I also adjust the dpi with out hurting the photo

You can do whatever you like to the DPI without affecting the image - because it's totally meaningless until you actually go to print something. Go on, try it. Take an image and save two copies - Image_1.jpg and Image _1000.jpg. Change the first to 1 dpi and the second to 1000 dpi, then examine both images. They are identical.

What matters is the pixel dimensions of your images. Yours are 3264x2448. If you ask a print shop to print one of these at 6" x 4" then they'd be able to print at 544 dpi. A 12" x 8" print would be 272 dpi - which would still be acceptable.

You could print a poster 6 foot x 4 foot at 45 dpi. Now most people would say that 45 dpi is far too low for a decent print. And they're right - for a print that you're going to be viewing from 10 inches away. But such a large poster will be viewed from several feet away - and will look perfectly fine. Just check out a billboard close-up sometime.

I reckon that any image of 6 Megapixels or more (yours is 8 MP) can be printed at any size you like. When I get prints made I crop them to the correct aspect ratio and send the file with no other changes to file size, image size, dpi, etc. The printer then prints them at the highest possible value for dpi.

 

[Dale_tem]

You can do whatever you like to the DPI without affecting the image - because it's totally meaningless until you actually go to print something. Go on, try it. Take an image and save two copies - Image_1.jpg and Image _1000.jpg. Change the first to 1 dpi and the second to 1000 dpi, then examine both images. They are identical.

When you do this, make sure it doesn't resize the image.

Corel Photopaint will change the image size/quality if when adjusting DPI you have a physical size show for image size (mm,cm, inches etc.). If the size is shown in pixels it will not change the image size/quality only the size it prints out.

If an image is 1000 pixels wide and its printed at 100dpi, its 10" wide. If you print it at 10dpi its 100" wide. The number of pixels hasn't changed, just how big each pixel is decided by the dpi.

 

[AJA Photography UK]

Thanks for all the advice will look at them seriously over the coming days