Canon 10-18 EF-S Equivalent focal length question

Basil

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Jul 29, 2013
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I recently bought the subject lens for my Canon 7D Mark II. Given it is specifically for crop sensors, is the focal length really 10-18 or is it the equivalent of 16-28.8 ?? In other words does it yield the same range of field of view as a 10-18 EF lens would on a Full Frame?
 
Basil said:
I recently bought the subject lens for my Canon 7D Mark II. Given it is specifically for crop sensors, is the focal length really 10-18 or is it the equivalent of 16-28.8 ?? In other words does it yield the same range of field of view as a 10-18 EF lens would on a Full Frame?

No, the 7D is a 1.6x crop sensor...meaning FF equivalent would be 16mm (10 x 1.6 = 16) at the wide end.
 
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Basil said:
...is the focal length really 10-18 or is it the equivalent of 16-28.8 ??

Both. Focal length is an intrinsic property of a lens, regardless of the sensor behind it. So, the focal length really is 10-18mm, and when used on a 1.6x crop body like the 7DII it delivers a field of view equivalent to a 16-29mm lens used on a FF camera.
 
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The focal length is intrinsic to the lens, and it really is 10-18mm. If you mount it on your 7D and set it to, say, 11mm, you will get the same image as the full-frame 11-24 will give you at 11mm on the same camera.

If you could mount it on a full-frame camera, the image wouldn't cover the whole frame, but the fraction that it did cover would record the same image as that fraction would with a full frame lens set to the same focal length.
 
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neuroanatomist said:
Basil said:
...is the focal length really 10-18 or is it the equivalent of 16-28.8 ??

Both. Focal length is an intrinsic property of a lens, regardless of the sensor behind it. So, the focal length really is 10-18mm, and when used on a 1.6x crop body like the 7DII it delivers a field of view equivalent to a 16-29mm lens used on a FF camera.

Ok, that's kinda what I thought but couldn't convince myself 100%
 
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johnf3f said:
I hear that it is an excellent lens for the price - let us know how you get on with it. I am thinking that it would be a good travel/landscape lens for my 7D2.

I'm using it on a Canon 7D Mark II and love it! One of the things you give up with a crop sensor is decent wide angle. This lens makes up for that! Even though it is not a super bright lens, that is somewhat made up for in that it has IS and your camera has fairly good high ISO capability (not the best there is but pretty good). It is about similar build quality to the infamous nifty fifty, but honestly I think it ranks as one of the best "bang for the buck" lenses Canon sells.
 
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Basil said:
johnf3f said:
I hear that it is an excellent lens for the price - let us know how you get on with it. I am thinking that it would be a good travel/landscape lens for my 7D2.

I'm using it on a Canon 7D Mark II and love it! One of the things you give up with a crop sensor is decent wide angle. This lens makes up for that! Even though it is not a super bright lens, that is somewhat made up for in that it has IS and your camera has fairly good high ISO capability (not the best there is but pretty good). It is about similar build quality to the infamous nifty fifty, but honestly I think it ranks as one of the best "bang for the buck" lenses Canon sells.

Thanks Basil!
I normally use a 1 series full frame camera and a 16-35 F4 L IS for wider angle shots but this is a bit big and heavy for travel. This is why I am considering the 10-18 - small, light and cheap! It wouldn't get used very much so there is no point in spending a fortune!

I will have to see what's in the Piggy Bank. I am off to try out the 1DX Mk2 in a few days so all ideas may be off!
 
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