Have you ever faced the predicament of having to resize images and do not know where to begin?
There is always a debate between the people that actually print images and designers or photographers.
Pixel quality is always a really good question that we have to face and when you initially get introduced to website design, you are unaware of some of the pitfalls that you might face when having to upload files or download images with huge pixel counts.
The first question you need to ask yourself is what would I like to do with my image?
I have worked out a good idea of how pixels work.
To answer your question, there might be a few options:
If you are going to print onto an A4 paper, then then you look at the size of an A4 page. The width is normally two-hundred-and-ten centimeters and if you would like to transform it into pixels, then you need to convert that to inches, so basically you are going to take 210 and divide it by 25.4 in order to get that size of 8.26772 inches, because you have 25.4 mm in 1 “. Now, for printing, you need 300 pixels per inch or otherwise known as dots per inch (dpi), so you take 300 dpi x 8.268″ = 2480 pixels wide
To calculate the height of the A4 High Res Print image, you take 300 dpi x (297 mm / 24.5mm/”) = 3507 pixels high
So, to get a really good quality A4 print image, you would need an image of round about 2500 wide x 3500 high.
The size of an image of that size could work out to be round about eight to ten Megapixels, so a 10.2 Megapixel camera should be adequate to do that job.
If you are going to use if for internet marketing, then you don’t need so many dots per inch anymore and you could get away with around 80 dpi, this reduces the file size dramatically. You would probably look at less than 2 Megapixels.
I have found that website developers use dramatically reduced sized images to increase the speed on their web pages, and from what I know is that the new imaging software programs that you get are very good with reducing images and yet retain the quality.
Really tiny squares of 100 x 100 pixels are very minute in file size, you are probably look at about 10 to 50 kb.
Then you also might want to print huge images onto posters or bill boards, but it depends once again on the printer and what kind of settings he might require. They could even go down to 20 dpi, depending on the requirement.
Please give us a shout if you have any questions and I will try and answer it to the best of my ability.