Idiot question

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Lazarus65

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Okay, so I have a Nikon D5200 which is an APS-C format sensor.
I know that if I fit a full frame lens to it the crop factor effectively increases the focal length by 1.6 i.e. 50mm full frame becomes 80mm equivalent.

However, all my lenses are Nikon DX, i.e. designed for APS-C sensors so if my lens says 18-55mm, is that the full frame equivalent or am I dealing with a 28.8-88mm?

Cheers.
 
The crop factor on a Nikon DX is 1.5 not 1.6 - that's on the darkside Canon:)
Focal length is always the same no matter what the sensor size what changes is the field of view due to the smaller sensor size.
So your 18-55 DX lens gives you a field of view of 1.5 x the focal length = 27-82.5mm

Just to add: The image circle is normally smaller on DX lenses that is why they are mostly lighter and cheaper the image circle required for a FX lens is larger so a FX lens will work on a DX camera but rarely the other way round - unless you don't mind vignetting.....
 
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Steve said:
The crop factor on a Nikon DX is 1.5 not 1.6 - that's on the darkside Canon:)
Focal length is always the same no matter what the sensor size what changes is the field of view due to the smaller sensor size.
So your 18-55 DX lens gives you a field of view of 1.5 x the focal length = 27-82.5mm

Just to add: The image circle is normally smaller on DX lenses that is why they are mostly lighter and cheaper the image circle required for a FX lens is larger so a FX lens will work on a DX camera but rarely the other way round - unless you don't mind vignetting.....
Click to expand...
Yeah I naiveley thought that it being a dedicated DX lens they might design it to ACTUALLY be 18-55mm. How wrong was I?
 
... But it is 18 to 55 mm, it is just that an APSC-C sensor covers a smaller area of the image circle than a full frame sensor would. The numbers refer to the actual focal length not the equivalent full frame focal length. Confusing, I know.
 
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Glenn said:
... But it is 18 to 55 mm, it is just that an APSC-C sensor covers a smaller area of the image circle than a full frame sensor would. The numbers refer to the actual focal length not the equivalent full frame focal length. Confusing, I know.
Click to expand...
It's damned unneccessary at my time of life!
 
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