Ratio query for printing

Carlh

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Ok, this is a question thats been asked a million times (on google) and I feel silly asking it (again) as I cannot get my head around it - but I have yet to see a simple straight forward answer, giving me pixel counts which I dont need, I just want something simple like this:

My camera shows me ratios on the lcd screen of
3:2
4:3
16:9
1:1

If someone could explain this bit (but the table is more important, please just say 3:2 - 6x4,9x6,12x8, just for reference), I dont care about mm or pixel count - just give me a table based on ratio's above.

The only thing that makes sense about that bit, is that 3 goes into nine 3 times and 3 goes into 6, 2 times for a 9x6 and for a 6x4, 2 goes into 6, 3 times and 2 goes into 4, 2 times so both are 3:2

12x8 - 3 goes into 12, 4 times and 3 doesn't go into 8, but 4 goes into 8 2 times, 4 goes into 12, 3 times so that must be a 3:4/4:3

To confuse me even more, 12 x 8 and 6 x 4 look like they should be the same ratio, but my calcs above show one is 3:4 and the other 3:2 :O My head is going to explode.

- but what about 7x5 ? ?

Please first, put me out of my misery with a simple table - then try and explain to me as if I were a 5 year old how I can figure it out so if I want to go to bigger prints, how to account for it all.

Getting me to understand this would be my "A-ha!" moment.

Appreciate any help not sarcasm about my intelligence :D
 
12x8 - 3 goes into 12, 4 times and 3 doesn't go into 8, but 4 goes into 8 2 times, 4 goes into 12, 3 times so that must be a 3:4/4:3

It's basic maths and I'm not very good at it but you are wrong-ish with the 12x8

The ratio is always the same but the number may differ as long as the number can ne divided into both the long and short sides.

3:2 ratio

6x4
9x6
12x8
15x5
18x12

4:3 ratio
8x6
12x9
20x15


The ratios are worked out as eg;

(3;2) three times the length and two times the width
(4;3) four times the length and three times the width

and so on for all ratios

It doesn't matter what number you use as long as it's the same number and can be divided into both sides
 
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3:2.............3x2........6x4........9x6.........12x8...15x10...18x12...21x14...24x18
4:3............4x3........6x4.5.,...8x6.........12x9...16x12...20x15...24x18
16:9..........4x2.25...8x4.5...12x6.75...16x9...
1:1...........anything square
 
Just divide one number by the other to get the ratio.

So, 12/8 = 1.5 and 6/4 = 1.5 therefore they are the same ratio (3:2)

If you want a print that's 3:2 ratio and 48 inches on the long side, 48/1.5 = 32 therefore you will get a print 32 inches on the short side.

So where did you get the "3" : "2" calculated from 1.5 ...

7x5 is 1.4 (7/5) what do I multiple 1.4 with to get a ratio that I know will fit? (i.e. 4:3/3:2/16:9)

Its still not making sense, it sort of is but not clicking with me.
 
3:2.............3x2........6x4........9x6.........12x8...15x10...18x12...21x14...24x18
4:3............4x3........6x4.5.,...8x6.........12x9...16x12...20x15...24x18
16:9..........4x2.25...8x4.5...12x6.75...16x9...
1:1...........anything square

Thats great and something i can just keep noted down, what ratio for a 7x5 (or 7x5.5) i guess?
 
So where did you get the "3" : "2" calculated from 1.5 ...

7x5 is 1.4 (7/5) what do I multiple 1.4 with to get a ratio that I know will fit? (i.e. 4:3/3:2/16:9)

Its still not making sense, it sort of is but not clicking with me.

3/2 = 1.5 (or 2*1.5=3 if you prefer).

3:2, 4:3, 7:5, 16:9 are the terms we use simply because they are the lowest whole numbers which fit the ratio (and are therefore generally the simplest to use for working out what size print you want as well).
 
It's a ratio. 3:2 = 3 to 2.

For every 3 measurements in one direction, there are 2 in the other direction.


Steve.
 
7x5 is the ratio, multiply them both by any number you like. Random example, 105x75 is a 7x5 (7*15 = 105 and 5*15 = 75).
sorry I should have said, a 7x5 print - what ratio would be best to use for that, with minimal cropping from my ratios that the camera has : 4:3, 2:3 etc..

7x5 is the ratio, multiply them both by any number you like. Random example, 105x75 is a 7x5 (7*15 = 105 and 5*15 = 75).
Where did the number 15 come from. I think that part of the formula might be my "missing link".

Other than using Gez's table, I would like to figure it out but I'm seeing numbers appear that have come from nowhere and wondering where they have been plucked from.

Right, let me see if I get this:

a 6x4 print = 6/4 = 1.5

1.5 goes into 6 3 times
1.5 goes into 4 2.666666 times

Doesn't figure.

:( very frustrating, im not seeing the wood for the trees.
 
what software do you use?
 
Just for testing purposes
Not sure if these will appear as Im not sure how to use the flickr permissions but:
Took these using two aspect ratios in the camera,
this one was at 4:3
14616766414_85b3dfc2a5_b.jpg



this one is 3:2
14616767914_734ce9531b_b.jpg


aside from the obvious movement i made while lowering the camera, changing the setting, i've taken basically the same image, other than the aspect ratios.

Setting it to crop (in photoshop) to a 7x5" print, both have the equal amount of space cut off.

Is aspect ratio IN CAMERA, only affected when im printing FROM the camera? I see no difference when downloading a RAW.

If I crop both the above to 6x4, nothing gets chopped off, so my camera appears to be doing nothing to the image regardless of my aspect ratio set in-camera. Please tell me Im not losing my mind.

(as a test I repeated it again and its the same, looks exactly the same in-camera).
 
FORGET the in camera aspect ratios, they'll just confuse things
 
stick to the 3-2 ratio as it's the same as the sensor
 
Your images posted above are both 3-2 ratio, are they screen grabs?
 
stick to the 3-2 ratio as it's the same as the sensor
Its just I have to print odd sized 7x5's this evening and dont want to screw it up :S

WHat makes it worse, is that I have cs6 installed on my PC (64bit), but obviously I cant re-use the license to install it on my 32bit laptop which is more mobile as I have to take the kit out with me, any recommendations on easy quick cropping software that basically just has the cropping section of photoshop in a free app? :)
 
no, taken off my 600d , went into menu settings changed aspect ratio to 3:2, took a photo, then into 4:3 took a photo (might have been the other way around)

I have a feeling that the 600d only lets you see what the 4-3 ratio would look like in the viewfinder but does not reduce the size from 3-2 to 4-3 in reality

Try Faststone for cropping and much more, best free image software on the net

http://www.faststone.org/FSViewerDownload.htm
 
sounds good, i stayed away from that because i saw the "buy" button but looking at the license requirements providing I dont use it for commercial. cough cough. i can use it for free. Will go get a copy now.

Am also considering going for photoshop cc as its only £9 a month and I can have it on two computers at the same time (though not running at the same time). Will try both alternatives - cheers for that - whats your name, cant keep calling you "admirable" :) even though you are :)

thanks again :)
 
Jim
 
Thats great and something i can just keep noted down, what ratio for a 7x5 (or 7x5.5) i guess?
1.. With every ratio devide the big number by the small one
2.. ie 7 devided by 5 equals 1.4
3.. when you want to print then multiply the shorter side by 1.4 to get the longer one
4x1.4= 5.6 so it would be... 5.6x4
5x1.4= 7 so it would be... 7x5
6x1.4= 8.4 so it would be... 8.4x6
7x1.4= 9.8 so it would be... 9.8x7
8x1.4= 11.2 so it would be... 11.2x8
9x1.4= 12.6 so it would be... 12.6x9
10x1.4= 14 so it would be... 12x10

for the others devide 3 by 2 equals 1.5
4 by 3 equals 1.33
16 by 9 equals 1.77
 
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Where did the number 15 come from. I think that part of the formula might be my "missing link".

Other than using Gez's table, I would like to figure it out but I'm seeing numbers appear that have come from nowhere and wondering where they have been plucked from.

Right, let me see if I get this:

a 6x4 print = 6/4 = 1.5

1.5 goes into 6 3 times
1.5 goes into 4 2.666666 times

Sorry for the slow reply Carl, timezone differences. Sounds like you're getting on top of it now anyway.

4 goes into 6 1.5 times, that's the important bit.

15 was just a random example - saying you can keep the same ratio if you multiply both numbers by the same amount.

As said above, don't bother cropping in camera. If you know you're going to be printing at a ratio other than 3:2 (which is the ratio of your sensor / whole image off the camera) then just be mindful in your compositions. Leave some space towards one side to allow you to crop in post.

3:2 is longer and skinnier than the other ratios. So, you know your prints will be chopping a bit off the long edge, and therefore you need to leave some dead space towards one end that you don't mind cropping off in print. (Besides 16:9 which is a movie ratio, set your camera to record video and it will shade the top and bottom of the LCD screen to show you a 16:9 ratio)
 
1.. With every ratio devide the big number by the small one
2.. ie 7 devided by 5 equals 1.4
3.. when you want to print then multiply the shorter side by 1.4 to get the longer one
4x1.4= 5.6 so it would be... 5.6x4
5x1.4= 7 so it would be... 7x5
6x1.4= 8.4 so it would be... 8.4x6
7x1.4= 9.8 so it would be... 9.8x7
8x1.4= 11.2 so it would be... 11.2x8
9x1.4= 12.6 so it would be... 12.6x9
10x1.4= 14 so it would be... 12x10

for the others devide 3 by 2 equals 1.5
4 by 3 equals 1.33
16 by 9 equals 1.77

THats exactly the formula I needed - bang on! I'm keeping this as a sticky on my desktop :) Thanks Gerry, you're a star - thanks to everyone for their patience and help, I just needed that explaining in a way my thick head could get around lol - you're all great and thats why I love coming to TP, I feel like it is a proper community. :)

Sorry for the slow reply Carl, timezone differences. Sounds like you're getting on top of it now anyway.

4 goes into 6 1.5 times, that's the important bit.

15 was just a random example - saying you can keep the same ratio if you multiply both numbers by the same amount.

As said above, don't bother cropping in camera. If you know you're going to be printing at a ratio other than 3:2 (which is the ratio of your sensor / whole image off the camera) then just be mindful in your compositions. Leave some space towards one side to allow you to crop in post.

3:2 is longer and skinnier than the other ratios. So, you know your prints will be chopping a bit off the long edge, and therefore you need to leave some dead space towards one end that you don't mind cropping off in print. (Besides 16:9 which is a movie ratio, set your camera to record video and it will shade the top and bottom of the LCD screen to show you a 16:9 ratio)

Thats good too Jay - and I did pay attention to what you and others put yesterday and made sure I had some cropping space for the 7x5's, a photographed at 4:3 to minimise cropping area and it worked a treat - thanks very much! :)
 
If your actual final size will be 7" x 5", shoot slightly loosely (in terms of framing) then crop in, setting the crop tool to 7" x 5" @ 300 pixels per inch (or dots per inch) resolution.

Not sure where the 7x5 print size came from - it doesn't fit the "standard" 3:2 ratio that most SLRs (as in 35mm and DSLR) produce. I used to get places to do me 7 1/2" x 5" prints from film to keep as much of my original framing as possible.
 
If your actual final size will be 7" x 5", shoot slightly loosely (in terms of framing) then crop in, setting the crop tool to 7" x 5" @ 300 pixels per inch (or dots per inch) resolution.

Not sure where the 7x5 print size came from - it doesn't fit the "standard" 3:2 ratio that most SLRs (as in 35mm and DSLR) produce. I used to get places to do me 7 1/2" x 5" prints from film to keep as much of my original framing as possible.
a request by a school that I have been taking photographs for. Most likely something from the old-film days perhaps?
 
7x5 is a sheet film size.
 
Its just I have to print odd sized 7x5's this evening and dont want to screw it up :confused:

WHat makes it worse, is that I have cs6 installed on my PC (64bit), but obviously I cant re-use the license to install it on my 32bit laptop which is more mobile as I have to take the kit out with me, any recommendations on easy quick cropping software that basically just has the cropping section of photoshop in a free app? :)
One licence lets you install on one PC AND one laptop ...
 
One licence lets you install on one PC AND one laptop ...
I've got the trial version on the lappy to see how it goes, though its winxp on the laptop, Im restricted with camera raw and the 6d isn't on the camera raw features :S Its not too bad though as I will be using the laptop mainly for producing photos at events, which I shoot both JPG and RAW and JPG is fine for on-the-spot printing. Just wondering what features I lose at £8 a month, I think the versions are cut-down somewhat, but I may get a new laptop anyway, just scouting around for one
 
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