Very simply, it's an infinitely adjustable extension tube, mostly (if not always) used for macro work. Some also include a slide copying attachment.

It also facilitates very accurate focusing on static objects. Camera/bellows/ lens focus can be adjusted in very small steps when the whole rig is mounted on a tripod.

Pentax bellows are beautifully engineered too.

Amin: What is the purpose of your post? Do you have a problem with it?

Correct Amin, they are Pentax bellows. : :

You're welcome.

I was (not) very surprised to find almost no information about the Memory feature in the manual.

I wonder what else it does . . .

Found it.

Rec. Mode menu > File No > Untick it, take a shot.

Repeat to re-tick File No.

I guess this camera must have had a card inserted that contained images with high numbers.

Sorted now.

Having bought a used K20D from a forum member a few months ago, I've only just been able to check it out having arrived back in UK for a while.

Shutter count is as I was told at circa 2760 but the image number is 9500+.

Can this be reset, I know it'll clock over to 0 at 10000, but I'd rather like to reset it now.

Any ideas?

The camera I used for many years was a Super-A bought with the A 50mm 1:1.7 lens. That camera most often had a Takumar (non-SMC) 70-210 lens on it with which I recorded most of my family's earlier life.

Since 'going digital' I've probably taken more images in the last few years than I did in almost 20 years with that combination.

SMCP-FA 100mm Macro for me, I'm sure it'd get plenty of use. A solar charger might be useful too.

An early Pentax digital experiment involved a MZ-S body and (I think) a Kodak sensor.

I think they made the right decision to use neither that body, or that sensor.

I am more than happy with the ergonomics of the K10/20D + grip combination.

Clarky, it's very easy to make an adapter to fit your ringflash on the bayonet mount of the reversed lens.

Take an old filter with a suitably sized thread (I chose 58mm) and remove the glass.
Take an old manual extension tube and remove the K mount.
Take some araldite, the two items from above . . . you can guess the rest.

The only thing is the adapter does not lock onto the lens, but that's no real problem.

Notice that you haven't got any light into the ant hole in your second shot. This adapter will probably fix that because at the moment, your reversed lens is causing a black spot.

If you are disappointed with your images, there could be a problem with your technique, the camera setup, lens choice.

The Pentax system is capable of producing top rate images, in the right hands.

It would be interesting for you to share with us what lenses you use. Consumer zooms, primes, DA* lenses, which?

Switching brands should be the very last resort after ensuring you are consistently getting the very best that your equipment and technique is capable of. Even then, a substantial amount of research will be needed, not to mention an unending supply of cash, to make sure that your next system is right for you. It's not something you do on a whim, unless you have more money than sense that is.