The files for this reference page were generously provided by Derby Chang from PDML. The files are all full size (10 MP) jpegs each about 1Mb in size
At F3.5
At F4.0
At F5.6
At F8.0
At F11
At F16
At F22
As you can see, the DA 21 lens is essentially unusuable on film.
At F2.8
At F4.0
At F5.6
At F8.0
At F11
At F16
At F22
It seems to me that this lens can be used on film but one has to be aware of the potential sharpness fall off towards the corners.
At F2.5
At F2.8
At F4.0
At F5.6
At F8.0
At F11
At F16
At F22
The performance here is similar to that of DA 40/2.8.
