So I’ve been meaning to try this out since I bought my camera but never got around to it before – so here goes. It’s a simple little test that I looked for on-line at the time of choosing my camera – with little success – however, that was a while back!

Basically I wanted to compare different sensor sizes.

I used my 6D (full-frame) and 550D (APS-C cropped sensor) for this crop factor test to compare my lenses and show the difference that the two sensor sizes make – a x1.6 crop factor.

Here you can see the results of the two cameras at 50mm

full frame – 50mm prime

APS-C cropped sensor – 50mm prime

OK, I didn’t bother focussing on the same area or using the same ISO – which in retrospect I should have done  but this is really just a zoom comparison test which these shots do show quite nicely.

Then at 24mm…

full frame – 24-70 @ 24mm

APS-C cropped sensor – 24-70 @ 24mm

at 70mm

full frame – 24-70 @ 70mm

APS-C cropped sensor – 24-70 @ 70mm

and at 200mm

full frame – 70-200 @ 200mm

APS-C cropped sensor – 70-200 @ 200mm

The cropped sensor certainly gets you in a lot closer but as you’ll see below, I need to check this carefully to see if the drop in quality outweighs the magnification.

I then tried the 10-20mm lens just on the 550D as it is a bit too wide for the 6D

APS-C cropped sensor – 10-20 @ 10mm

APS-C cropped sensor – 10-20 @ 20mm

which proved to be in the same ball-park as the full frame 24mm shot

full frame – 24-70 @ 24mm

and finally a couple of 100% crops of the 200mm shots – The focus wasn’t directly on this part of the chair – this test was about the size of the image not the quality – but the full frame image certainly looks sharper – which is a relief as it is a newer and more expensive camera!! – The cropped sensor it would appear does get you in closer but the quality of the image isn’t so great.

APS-C cropped sensor – 70-200 @ 200mm at 100% of an 18 megapixel image

full frame – 70-200 @ 200mm at 100% of a 20.2 megapixel image