Full Frame 6D cropped in to APS-C sensor size vs 70D APS-C

[carlapappalardo]

I'm interested in the comparison of full frame to cropped sensor dslrs. I am curious if anyone has tested (or knows where I can see results) a full frame such as the 6d and zoomed in to the cropped size you would get with say the APS-C 70D?

My reason for asking this is that while I would prefer the clarity one would get with the FF, I wonder about the higher zoom one gets when using a FF lens on an APS-C camera? 

Any thoughts?

Thanks.

[cicopo]

Lots of info on this can be found with a Google search but basically the 5D2 files came out at about 8 mpixels (roughly the same as the 20D, 30D & 1D2 & 2n) when cropped to a 1.6 equalent. A Nikon D800 file is about 14.5 mpixels at the 1.6 crop. An 18 mpixel crop sensor would be about 40 mpixels IF it was full frame. 

[carlapappalardo]

My searches didn't reveal the type of specific answer I was looking for on the 2 canon's in question. Thanks though and I'll keep looking. 

[cicopo]

It's just math, compare the ratio of the sq in (or mm) of a 1.6 sensor to a FF sensor & then use the ratio to calculate the mpixels.

Canon says the sensor in a 40D is 22.2 X 14.8mm (328.56 sq mm)

And  in the 5D2 it's 36 X 24 mm (864 sq mm)

so the 1.6 crop sensor is roughly 38-40% of the  FF sensor.

 If a FF camera had 24 mpixels a 1.6 crop of it's image would have about 9,6 mpixels

or the reverse ratio is about 2.6 so the 18 Mpixel sensor would grow to produce 46.8 mpixels

These aren't exact but would be close