What is meant by image size?
Digital images are just massive grids with each square (or pixel) having a particular colour. Image size usually just refers to the number of squares on the grid. Generally speaking, the more pixels the more detail.
How big a size do I need?
If you are using it on the web (facebook etc) usually between 600 and 1200 pixels on the long side would be ample (big screens and new ipads are over 2000 pixels wide and oldish laptops and phones closer to 1000). So if you want a desktop image for a big monitor you'll probably need an image over 2000 pixel wide.
I want to print it. How big will it need to be?
Magazine quality usually requires 300 pixels an inch. So a 12 inch high front cover would need 12 inch x 300 = 3600 pixels on its longest side.
If you print at home on a good printer you can probably print at only about 150 pixels an inch so an A4 photo would require 11.7 inch x 150 = 1755 pixels on the long side.
As you reduce the pixels per inch you introduce slight softness and blockiness into the image. Printing at home I've found I could barely detect a difference between an image printed at 300 pixels an inch and one printed at 180 pixels an inch. The same one printed at 150 pixels was just about OK but at 100 pixels it looked poor close up.
What do I need to print something to hang on the wall?
Here you can get away with printing at lower pixels per inch because you look at the image from further away. I would still suggest at least 100 pixels per inch which would mean for an A1 print you'd want at least 3300 pixels (33 inch x 100) along it longest side. As a rule, if you want a big print get as many pixels as you can.
Can you do special processing?
We can probably do anything you want. Different crops, black and white etc are no problem. Just let us know. If you want anything else just ask for a quote.
What file type do I need?
For almost all non commercial work a jpeg will be fine. They produce small files for the number of pixels so they are emailable and quick. The problem with them is they don't leave much scope for editing if you want to play with the image yourself. The quality varies according to the amount it is compressed and the quality deteriorates each time it is re-saved. So if you want to manipulate an image yourself you might be better having a Tiff. This will be a much bigger file but will have a lot more of the original information that a jpeg would have lost.
A jpeg has 8 bits of info to describe each pixel, a tiff has 14 (actually 16 but the camera only produces 14) which might not sound important but is the difference between having 256 shades of grey and having 16000 shades of grey. The time when you really appreciate the difference is if you want, for example, to slightly darken a sky that looks almost white.
If you want a Tiff there's an additional £2 charge per image and we'll send you a dropbox link to download it.
Where can I get a big print done?
This isn't a recommendation but the last time we checked www.zip-posters.co.uk/ did A0 prints onto paper for less than £15.00. All you do is to upload the image we've sent you to their website. There are numerous other options including different sizes and printing onto foamex or canvas etc.