photo ratios

[Briones1208]

I was never good in math and i don't think i really paid attention. I feel a little dumb asking this question but can anyone help explaining photo ratios? What size would a pic be if its suppose to be at 2.5:1?

[dtscds]

Just multiply both sides of the ratio by the same number. So 2.5:1 multiplied by 4 would be 10x4, by 10 would be 25x10... One side is always a multiple of 2.5 and the other is a multiple of 1.
Just treat the ":" like it is the "x" in the dimension.

[Briones1208]

thank you

[kenw]

A ratio doesn't necessarily give you a specific print size, altho the sizes it DOES give you have that ratio in common.

for example: 1:1.5 is a ratio which will give you 4x6 and 8x12.
Note how the short dimension of the print (4 or 8) multiplied by the 2nd part of the ratio (1.5) equals the 2nd dimension of the print (6 or 12)

So.... if you crop a pic to print at 4x6, the same crop will print perfectly at 8x12.

another example: cropping to 1:1.25 will give you both 8x10 and 16x20 prints