Welcome from another ex-Oly user (in my case an E-1). Have fun with your gear! I agree with Greytop that Oly zooms are hard to beat though.

One thing which may be of interest: the Sigma 10-20 on 4/3 is equivalent to something like a 14-26 on APSC. One lowish cost option that may be worth jumping on while you still can (Park Cameras) is the recently-discontinued Pentax 16-45 f4. If you didn't live near the widest end of your Sigma, you may find the 16-45 a very cost-effective (£229) and decent IQ upgrade from the 18-55 kit lens. It's not WR (but then neither is the Sigma). I recently picked one up secondhand and have been very impressed with the IQ (build is decent but not outstanding).

I've found my K100D Super works very well with "hybrid" rechargeables such as "Hybrio" or "Eneloop". These drain very slowly and still have power even after you've left the camera unused for a considerable time period.

Best performance comes when using Lithiums - esp Lithium CRV3s (not rechargeable though). These are great if you are a relatively light user of the camera, and should last for over 1,000 shots unless you use a lot of flash. However, not great for the pocket or for the environment.

Finally - remember that any battery will perform less well in current cold conditions - they drain more quickly in the winter.

SmugMug is back up now so here are a few Tamron 500mm samples (Pentax K20D in Botswana):













In my view, a good cat or mirror lens used with care can deliver results far in excess of what the nay-sayers will suggest. I'm happy with what I'm getting - and it also makes me smile that my first PPG acceptance (the elephant above) was taken with a £45 secondhand lens that many people on the photography forums will tell you aren't worth bothering with. If you had a good experience before, I think with practice you will again (and from what I've read, your Sigma is a good lens that's up there with the Tamron as among the best of breed). Have fun!

I have the Tamron 500mm F8 and have used it frequently on dSLR. I find my best results:

(1) are when I use a monopod and keep SR switched on (handholding is a no-no with these lenses, despite the temptation to do so given they are so compact)

(2) are when I keep the shutter speed to at least 1/125 and preferably faster - so good light is a must unless you bump up the ISO

(3) are when I shoot RAW to give me the maximum data to play with afterwards - even good cat lenses have reduced contrast compared to conventional glass, and starting with a RAW file can really help

I also tend to use the camera's "catch in focus" feature, which often works well. I will try and post some samples in this thread sometime, but SmugMug (which is where they are hosted) is going through some maintenance tonight so I can't get at them!....

I have K-7 and use the Tamron 180SP f2.5 with a Tamron PKA adapter, and have not experienced this problem - all works as it should so I'm afraid it sounds to me as if there is something not quite right here.....

Sorry to bring bad news.

Jon

Thanks for the suggestions. Sadly this situation is the case with all of my lenses, including the kit 18-55 where AF and aperture ring shouldn't be an issue.... Will try the battery trick though and report back if it works.

I'm kind of thinking that because the camera is refusing to stop down and do an optical preview, there may be some kind of mechanical rather than electronic problem?

Jon

Hi - on hols in the States and my K-7 seems to have stopped stopping lenses (any lens) down from wide open. Optical preview no longer works. And dust alert has become greyed out as an option. Luckily have a back up K100DS but not very happy....

Manual focus or auto focus makes no difference; similarly happens with all modes (Av, P, etc).

Has this happened to anyone else, and am I overlooking anything obvious? Otherwise I think it may need to be sent to the doctor when I get back.

Hoping you can point me in the direction of my own stupidity rather than a lengthy time without the camera!

Cheers,

Jon

Hi Simon - I came to the same conclusion as you with the Sigma and it lives with another forum member now! I bought a 16-45 which goes wide enough for me, but can see the attraction of the 12-24. Another option might be to buy the 15mm DA Ltd to stick in your pocket for the odd occasion when 17mm is not wide enough?

Glad all is well. As for the banks - anyone would think it was their money, rather than ours..... I guess I tend to work on the theory that most messes are "cock up" rather than "conspiracy", which was the case this time.

On the other hand, the good news for others shipping abroad is that Royal Mail Airsure was remarkably quick even in the run-up to Christmas.

Cheers All,

Jon

Thanks for letting us know! I ended up buying a Voigtlander 40mm Ultron lens instead, which I really love. And must stop looking at ads for FA Ltds because they will bankrupt me!