I bought a Senz macro extension tube (sorry I have not found any English web site describing this tube - a Swedish descriptions is here
PHOTAX - N ). The macro extension tube works perfectly with my Pentax K-5 and SMC Pentax DA 50-200mm/4-5.6 ED WR. Exposure measuring, aperture, auto-exposure, focusing, ... everything works.
However, when I try to use the macro extension tube with Pentax K-5 and Sigma 50/1.5 DG HSM it is a total disaster. Nothing works. Aperture information changes randomly and quickly; exposure indication quickly back and forth between max dark and max light; no focus indicator. If I take a photo it ends up all white or all black.
I guess that the problem is that the HSM lens (lens with built in focus motor) has a different connector layout than the lens without focus motor.
Do we have anyone on the forum that can explain the connectors of the Pentax mount?
Would I have the same problem with a Pentax SDM lens (a Pentax brand lens with focus motor in the lens) like the SMC Pentax DA* 300/4 ED (IF) SDM?
For your information; here is a picture of the contacts on the Sigma HSM lens:
Here is a picture of the tube front:
And here is a picture of the tube back:
Does anyone know of a macro extension tube set that works better?
I bought the Senz macro extension tube set new for approx. US$ 200. I am allowed to return it and get my money back. However, there is not much use doing that unless there is a better working macro extension tube set available that I can buy instead.
Thank you in advance for your help.
Last edited by TB-000; 09-03-2012 at 09:58 AM.