Film area

[david_nash]

Hi

 

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Just a quick question. How many times greater is the surface area of a 5x4" or 10x8" negative compared with a 35mm neg? I know I've read the answer many times before, but I can't find the answer.

 

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Thanks

 

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David Nash

[eric_boutilier_brown2]

A 35mm neg is 1"x1.5" is size, leading to an area of 1.5 square

inches. A 4x5 is (approximatly) 4"x5" which has an area of 20 square

inches - 13 times larger. An 8x10 shee is 80 square inches, or 53

times larger in area.

[david_haardt2]

To be even more exact, a 35mm negative is 24x36mm large (~

0.94x1.42") thus has a size of 864 square millimetres. A 4x5"

negative is 4x5" (102x127mm) large, thus has 12954 square

millimeters. A 8x10" negative is 8x10" (203x254mm) large, thus has

51562 square millimeters. So a 4x5" negative is approximately 14.99x

as large as a 35mm negative, a 8x10" approximately 59.68x. So 15x and

60x as good figures to have in mind ;-)

 

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Cheers,

[dan_smith]

The 4x5 and 8x10 actual image area is probably a bit less depending

on the holder used. You do lose a bit of image from the slides that

hold the film in place.

[doug_paramore]

If you enlarge the 35mm neg, the usable image area is even less, due

to the odd shape of the film. You lose a bit at each end when you go

to the 8x10 shape, less so with 5x7. I ain't smart enough to figure

out the specifics.

 

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Regards,

[stewart_ethier1]

The 4x5 image area is 3.75x4.75 (ANSI standard), or 17.8125 square

inches, not 20 square inches. Multiply by 25.4^2 to get 11,491.9125

square millimeters. 35mm is, as mentioned above, 24x36 = 864 square

millimeters. Therefore, the ratio is 13.30082465, or about 13.3.

 

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For 8x10, the image area is 7.7x9.7 (ANSI standard), or 74.69 square

inches, not 80 square inches. The corresponding ratio is

55.77199120, or about 55.8.

[pete_andrews]

This business of film area is a complete red-herring. 5"x4" is NOT

13.75 times better than 35mm just because it has that much greater

area. It's only 4 times better. The linear enlargement needed for a

given print size is the only factor that should be taken into

consideration when comparing formats.<br>Knowing the relative areas of

different film sizes is only of any possible use in calculating how

much processing solution you need.