The main mechanical difference between Adaptall '1' and Adaptall-2 mounts is that the Adaptall-2 lenses have the functionality to indicate their maximum aperture to Adaptall-2 mounts, whereas Apatall '1' lenses do not.

As I understand it, this doesn't affect us Pentax users, so we can use Adaptall '1' and 2 lenses and mounts completely interchangeably. I've happily used my Adaptall-2 PK/A mount with Adaptall '1' lenses.

The Adaptall '1' series had a PK mount only (labelled PK/M) which was equivalent to a Pentax M lens (green button metering required). The PK/A mount was introduced in the Adaptall-2 range and gave functionality equivalent to a Pentax A series lens allowing the control of aperture from the camera body.

I believe that for more 'complex' mounts, like Canon FD, it is only possible to use Adaptall-2 mounts correctly with Adaptall-2 lenses.

The 75-150 should be nice. Excellent build and quite good as an outdoor portrait lens. It's sharp for an 'old' zoom and I liked the rendering. Mine had a tendency to purple fringing in high contrast conditions, through.

I have played with stacking M42 teleconverters and things got very mushy, very fast! By the time I tried 3 with a fast 200mm prime (Chinon, I think), it was pretty much unsuable. Fun to try, although I found that the results were not as good as cropping an image from the the lens without TC.

Who made the Vivitar? My experience is that many of their lenses made by Kiron or possibly Komine (which have serial numbers starting 22 or 28 respectively) are pretty good. My experience is mostly wit primes, though.

PM sent

Payment received, thanks - the lens will be on its way on Monday.

No problem - a PM with the details in is on its way...

I'm thinning out my collection of manual focus lenses and have an M50/1.4 for sale (see this page for more info)

It's in very good condition, as shown in the pictures, with signs of careful use (slight rubbing to the edges of the focus and aperture rings). The optics are in good shape, with no scratches, marks or fungus (but a few specks of internal dust - nothing unusual for a lens of this age or that would affect the pictures).

It is supplied with the front/rear caps. Although I don't normally use them, I'd be happy to include a UV filter as well if you'd like one.

Looking at the going rate on eBay, I think that £60 delivered within the UK is reasonable and I'd be happy to investigate postage options to send it further afield if required. Payment preferably by bank transfer or alternatively PayPal (with the buyer covering the fees) please.

My 2p worth:

DA15 limited - Always in my camera bag. Small, light, portable and has the elusive 'pixie dust'
DA10-17 - I didn't think I'd like a fish-eye, but in many ways I prefer the rendering to rectilinear ultra-wides.
M85/2 - Great for people shots, small, comparatively light and with really nice IQ.
K135/2.5 - Had mine stolen recently, but a gem. Beautifully built, a pleasure to use and really good image quality. I'm be looking for another one.

Going slighty off-piste:

Tamron Adaptall SP 90mm/2.5 macro - Pretty good as both a macro and a portrait lens.
Helios 44 - Good IQ and very different rendering, plus serves as a reminder how beautifully engineered Pentax lenses of the same era are.
Tamron 17-50 - Excellent and a worthy upgrade from the kit lens; If I had to have just one lens, this would probably be it (for entirely practical reasons, though - it's technically very good but lacks the character and soul of the limiteds or older Pentax lenses...)

PM sent

Thanks everyone - I had a feeling it might not be entirely straightforward.

I think that's my main concern. Whilst I'd be very happy if they replaced my A50/1.7 with, say, a DA50/1.8, finding a new equivalent of a K135/2.5 is a bit trickier!

The Police and CID have been very helpful and they found some good footprints, and so, to quote them, will "go round and visit a few of the usual suspects. If we find any of their shoes that match, we'll search their house and try to leave it in a bit of a mess".

Interestingly, we have a pack of sterile needles and other kit for travel to places where you can't reliably get such things, which they found and didn't take, so if they were junkies, they weren't even very good at that!

Good advice - I'll certainly do this and have a busy weekend of photographing and cataloguing stuff ahead...

Earlier this week, some thieving ne'er-do-well decided to enter our house and help himself to a selection of phones, laptops and jewellery earlier this week. Fortunately my camera kit was largely missed (since most of it is in a cupboard high in the kids' playroom, which generally looks as if it has been ransacked already), but I lost my old K-m, A Z30 and Sony TX-5.

Whilst it is amusing, in retrospect, that they moved but didn't notice a flight case with my K and A lens collections in it (K28/2, A50/1.2, K85...) to empty out a drawer full of t-shirts (with nothing but t-shirts in it), going through the process of making an insurance claim highlighted how difficult it probably would be to get a fair settlement for old lenses in particular.

Does anyone have any experience, tips or advice on ensuring that their old lenses are adequately covered? My only other experience of insuring unusual risks is with classic cars, where specialist insurers offer an 'agreed value' policy. For these, they inspect your vehicle and agree its value when you take out the policy, as book vales on a 40 year old vehicle are negligible. Is there a similar scheme for classic camera gear?