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Jim G
8th of July 2005 (Fri), 02:26
This came to me as I was idly thinking today, I think this is the right bit to ask in... With cameras such as the 20D/350D (XT) and their 1.6x focal length mutiplier... Would it be possible to create a camera so that the sensor is larger than 35mm and thus, by my understanding, create a focal length multiplier that's less than 1?

I suppose the point is, if you were to do that and whack something like a 10-22 lens on it would you end up having an ultra-wide lens like 8-17 or something like that?

I know a little about medium format and larger cameras but not enough to know if they answer my question :p
Ikinaa
8th of July 2005 (Fri), 02:36
Medium format cameras have a sensor/film larger that 36x24.
But using a lens for 36x24 sensor on a larger sensor/film will give you vignetting.

a 6x4 film compared to a 36x24 will give you crop-factore of about 0.6, so a 50 mm lens on a 36x24 would be equivalent to a 30mm on a 6x4

(hope to have got the math right)
Rokkorfan
8th of July 2005 (Fri), 08:01
No it won't work because you lens only has an image circle just large enough to cover the frame (except for the TS-E lenses). If you were able to put a 10-22mm lens on a 1Ds you would see that it did not cover the whole frame - this is why it is a 10-22mm EF-S lens, not an EF.
Headcase650
8th of July 2005 (Fri), 15:10
If you were going to build something like this couldnt you move the larger sensor further away from the lens so that its image circle covered the entire sensor. Wait, that would just give you more resolution and not increase your angle of view.?

Hmmmm, I dont know nothin!
wilflee
8th of July 2005 (Fri), 15:33
Note the term "focal length multiplier" isn't exactly correct. The smaller APS sized sensor doesn't multiply the focal length of the lens. It only covers the image area of a lens 1.6x longer so you have a reduced field of view.
CoolToolGuy
8th of July 2005 (Fri), 15:48
If you were going to build something like this couldnt you move the larger sensor further away from the lens so that its image circle covered the entire sensor. Wait, that would just give you more resolution and not increase your angle of view.?

Hmmmm, I dont know nothin!

If the sensor moved further away from the lens, the focus would be affected.

Nice try, but I don't think it will work.

Have Fun,