wat the down side of using a full frame lens on a non full frame body?
wat the down side of using a full frame lens on a non full frame body?
F
Upside is most APC sensor will stand to benefit from the sweet spot (sharpness) that FF offers since only the center portion of the FF lens is used.
resolution.
FF lens r usually not optimise for the center of the pic.
it really shows when using FF lenses on aps-c body.
Huh??
It's often been said that using a full frame lens on an APS-C body allows you to utilize the "sweet spot" of the lens.
This seems to contradict your point, unless I've mis-read...
You can refer to dpreview website, for certain lens they have reviews for both FF and APS-C DSLR.
For example, the review of Sigma 50mm F1.4, the performance on FF is much better.
for APS-C:
http://www.dpreview.com/lensreviews/sigma_50_1p4_c16/page4.asp
for Full Frame:
http://www.dpreview.com/lensreviews/sigma_50_1p4_c16/page5.asp
I'm no lens scientist but I believe that this is one of the most over-rated "benefit" of APS-C sensors...
Bro bengchiat talked about resolution... lenses which have not-so-high resolving power will show their weakness on a high-mpx crop factor body, whilst may not be obvious to most eyes on a full-frame body.
Rmb, a 1.6x crop factor image is essentially a 33% crop of an image from it's full-frame image size.
The main advantage of a crop-factor body is greater pixel magnification, corner performance (since you're not even using the corner of the FF lens) and less vignetting.
Sharp in the centre does not mean sharper on a crop factor body.
I have to disagree here, FF bodies like the 5DM2 and D3X have even greater pixel density than most "crop" bodies out there which will be a even greater test of the "resolving power" of lenses, especially when edge resolution is taken into account.
Sabee, I think you are mistakened with regards with full-frame pixel density exceed most crop bodies. However, you are certainly right that corner performance is also a decisive factor, this is usually better on a crop factor body since you only utilise the centre of the lens.
Eos 5DII, 21 mpx - 6.4 µm
Eos 30D, 8.2 mpx- 6.4 µm
Eos 450D, 12.2 mpx - 5.1 µm
Eos 7D, 18 mpx - 4.3 µm
As seen from these values of pixel size, pixel density on a 5DII is lesser than most crop-factor bodies.
I'm no lens scientist but I believe that this is one of the most over-rated "benefit" of APS-C sensors...
Bro bengchiat talked about resolution... lenses which have not-so-high resolving power will show their weakness on a high-mpx crop factor body, whilst may not be obvious to most eyes on a full-frame body.
Rmb, a 1.6x crop factor image is essentially a 33% crop of an image from it's full-frame image size.
The main advantage of a crop-factor body is greater pixel magnification, corner performance (since you're not even using the corner of the FF lens) and less vignetting.
Sharp in the centre does not mean sharper on a crop factor body.
wat the down side of using a full frame lens on a non full frame body?
You can refer to dpreview website, for certain lens they have reviews for both FF and APS-C DSLR.
For example, the review of Sigma 50mm F1.4, the performance on FF is much better.
for APS-C:
http://www.dpreview.com/lensreviews/sigma_50_1p4_c16/page4.asp
for Full Frame:
http://www.dpreview.com/lensreviews/sigma_50_1p4_c16/page5.asp