Hi All,
I do not recommend the Pentax-K adaption to SIGMA SA Bodies.
In addition to the minor problems Uwe absolutely correctly pointed out above, the Pentax Flange To Film Distance does not exactly match SIGMA-needs.
Pentax-K (45,46mm)
SIGMA SA (44,00mm)
That means, that the Pentax-K lenses are ca. 1,5mm too klose to SIGMA's Image sensor.
In the effect you can focus wider than infifnity. Some lenses are that close to the camera, that you run into problems destroying your dust-protektor.
Well, these problems are neglectible for macro-tube-use certainly.
Better go the M42-way!
See you with nice pictures
Klaus
I do not recommend the Pentax-K adaption to SIGMA SA Bodies.
In addition to the minor problems Uwe absolutely correctly pointed out above, the Pentax Flange To Film Distance does not exactly match SIGMA-needs.
Pentax-K (45,46mm)
SIGMA SA (44,00mm)
That means, that the Pentax-K lenses are ca. 1,5mm too klose to SIGMA's Image sensor.
In the effect you can focus wider than infifnity. Some lenses are that close to the camera, that you run into problems destroying your dust-protektor.
Well, these problems are neglectible for macro-tube-use certainly.
Better go the M42-way!
See you with nice pictures
Klaus