Photobox & Image/Resolution

[InaGlo]

Might sound a silly question to those in the know but, as I need to get some A3 pics printed, I just uploaded a couple of images to Photobox.
I was disappointed to see that I would get cropping on the width of the pics as this alters the perspective somewhat.
I was about to click 'buy' anyway then I realised Id uploaded my pics with 72 dpi & not the 300 dpi I was once advised to always use for printing.
Just changed one of my pics to 300 dpi & it grew to 25mb, oh dear!
Does anyone know if I need to submit my pics at 300 dpi to buy A3 size prints from Photobox?
Ta!

 

[RobertP]

If the picture has enough resolution to be printed that size it wil be fine. DPI are just display settings - ignore it.

You cropping problem is one of proportions - the ratio of height to width. Your picture proportions have to match the paper.

 

[InaGlo]

Thanks for your help Robert ... the only numbers I never get in a muddle are the ones on my credit card!

 

[whitewash]

printing at 30x20, 18x12" etc (3:2 ratio) will prevent cropping on the majority of DLSR sensor produced images (olympus excluded of course)