K20D and manual lens - setting shutter speed?

I'm trying using the A 50mm lens on macro tubes, however I'm not sure if I do that correctly.

The tubes they are K-mount, but don't have el. contacts so focus and aperture have to be set manually. That's fine, the lens has an aperture ring and I allowed aperture ring use in the camera setup. But the camera displays F-- on the display and sets the shutter to the value proper for the wide-open aperture. So when I change aperture to 16 the picture is completely black. And if I use the 'optical preview' function, half-press shutter doesn't set the shutter speed.

I found the way - I set mode dial to manual, spot metering (both focus and brightness), choose aperture with the ring, focus manually, then use the optical preview (so aperture stops down) - and then press the green button to auto-set the shutter (or manually change with the front dial looking at the EV bar).

Is there any easier way of setting the shutter speed?

I have some experience with that setup.
Firstly find the appropriate menu in Custom Settings to change "Using Aperture Ring" to "Permitted" then use Manual on the dial as you are doing. Once you've set the desired aperture on the Lens, pressing the green button should then stop down the Lens & Meter. It can be well underexposed though so check result & decrease shutter speed or open aperture using ring on lens as required to give a good exposure.

No need for optical preview.

No, because of the K mount tubes you loose automation. Stop down metering by using the green button in manual mode is the way to do it.
After the initial meter reading you can compensate plus or minus using the
shutter dial (front)

Martin.

Thanks - I've just tried, it works without the optical preview just as you said One thing less to press / turn. Now I have to find some function to keep my hands more stable Oh, I found, it's a tripod

very useful thread this... thankyou

might be useful as a sticky for any other relative newcomers who have a new pentax dslr with some old lenses.

This subject (or variants on it) is one that comes up often!

Cheers, Kris.

Kris, the problem is with finding them. I spent some time searching and found helpful bits here and there, thus I was able to get some results, but still I was not sure if I'm doing right and is this the easiest / most 'proper' method to use manual lenses with macro tubes.

Very true. Sometimes quick searches turn up trumps on the net, sometimes it can take a bit of digging. I wonder if there is some way of setting up a FAQ type thing for the site? There are various recurrent questions. for example: manual lenses, back/front focusing, best AA rechargeable batteries all come to mind. What do people think?

Best wishes, Kris.

Maybe we should make stickies from the most ask questions, a separet area might also be good but then only the modderators should be able to add a topic or else it would still get a mess.

The trouble with a traditional style FAQ is that not everyone will agree with the info, and some of it will go out of date quite quickly and need frequent updating.

Too many stickies clutter up the place.

An index to some threads on popular topics might be good, though.

Sounds like a good idea. When you first join the forum and do a search you are bombarded by past threads and posts. Including odd ones like this that don't seem to make any sense in relation to the Heading.