Oh well
I was assuming that with all contacts connected the camera and lens would talk to each other properly (because they can't know that an extension tube is there). Maybe there is some slight difference in the SDM & Power Zoom mechanics??

In that case, I'll stop looking for the Kenko one then and make do with MF
Matt

I have a set of Triplus extension tubes that have the aperture and lens control contacts. Alas, it does not have the AF screw (none do), and nor does it have the SDM AF contacts (which causes a few troubles for the DA*50-135)

There is only one extension tube (think it was made by Kenko) that had the power zoom contacts as well - that would allow SDM focus But... can I find them to buy???

Personally, I think the reversing is a much better approach. Thankfully you can use any old lens that has an aperture control. So, that means a 50mm f/2.0 (or f/1.7) lens from the M42 screw thread era would do nicely. You should be able to pick one up for not much money at all

You could try out your 50mm to see what you get (just set the aperture to wide-open and hand hold it in front of your Sigma... carefully!). See what you get. If that looks good, then get some reversing rings and think about a second 50mm (since the rear element is exposed and could be damaged. You wouldn't want to do that on a current 50mm/f1.4 given their current price! :shock

HTH!
Matt

Oh it will... you've just got to know what it is!

First, some questions
- are you shooting RAW, or JPG.
- if RAW, what RAW converter are you using?
- can you post a full size example?

Matt

The only common issue I know of with the ME range is dirt getting into the ISO adjustment potentiometer. Typically gives very underexposed images, and wiggling the ISO/Ev dial will change the exposure.

I replaced the ISO pot on two ME Supers and one MEF (in the days when Pentax had a service department and would supply parts to end users).

...but that probably isn't your issue.
Matt

Yes, it's a beautifully made lens, and stunning quality. Had the chance to borrow the 31 and 77 for a day.

However... it does depend what you're taking! Comparing the 31 against the 24-90 I was amazed at the small difference between the two when stopped down to f/8 or so. The experience of trying the 31 gave me a new found appreciation for the other Pentax glass. Sharpness, colour and contrast were favourably similar. It saved the angst of longing for the 31

Check out these two images - Number 1 is the 31mm, and Number 2 is the 24-90. Even 1000 pixels doesn't do them justice - but at full res there's not much between them.

That said, when you use the 31 as demonstrated above (shallow DoF) it really does shine - certainly has a wonderful 3D quality about it

Matt

Tell me you're joking....

I seem to have the same problem on my K20D - here

AFAIK, P-TTL doesn't work on lenses that have manually set aperture.
When you use a Pentax gun, set to P-TTL, and set the aperture the flash will fully discharge (with no pre-flash). You have to switch the flash to "A".

For manual lenses you want to get a cheap(er) flash still. You only need "A" and "M" modes (preferably with adjustable manual discharge levels). It doesn't even need to be a 'dedicated' Pentax flash (though it is a small advantage).

Hope that helps!
Matt

It could be stray light entering the viewfinder and affecting the exposure.
Try covering the viewfinder when you view the top LCD
Matt

John,
Just be aware that if you use the flash infrequently that the NiMh batteries will discharge on their own. For example, if you use the flash every 2 months you will find that the batteries will be dead when you next use it.

That's why the newer NiMh technology (Eneloop/Hybrio/etc) is useful - keeps charge for up to 12 months

Matt

And that's where the newer Eneloop/Hybrio style NiMh come in handy
Only use those in my flashguns - they're always ready to be used! (Compared to my Metz 50MZ5 which self discharges every time I need it :roll
Matt