I think he might want to try somewhere a little closer to home (NQ = Australia).

Lens Adapter rings are available in 49mm, 52mm, 58mm, 67mm filter threads, as well as a macro adapter for PENTAX D-FA series macro lenses.

If your lens filter thread is 55mm diameter, use the 58mm or 67mm adapters with a 55-58mm or 55-67mm (preferred) stepper ring. The larger ring is preferred because a 55-58mm ring could be quite flimsy, the larger one being more robust IMHO.

Using a stepping ring is going to be a lot cheaper than buying a dedicated adapter, even if one does exist.

I'm going through just such an exercise right now, except I'm scanning my slides & negatives.

After they're scanned, they're binned.

I've got room in my cupboards for loads of other junk now.

PS: I have 4 separate copies of my pictures & videos, one copy is about 15 miles away from my house. Only an earthquake, war, or similar disaster will destroy all of them. If that happens, I won't be in any position to care.

Now you know why they are commonly referred to as 'Parcel Farce'.

Welcome Allan.

Thankfully I didn't have to sell anything to pay for the vet's bill for one of my dog's, a Golden Retriever, several years ago. She had to have an emergency hysterectomy for which the operation, after care, and medication cost almost £2000.00.

My wife often wonders how much it all cost, and if she were to ask, I would tell her. Thank goodness she's never asked . . . yet.

Enjoy your K-7 but before you buy, take a good long look at the K-5, it's a world beater.

There's an app for that.

The off button is my favourite.

Not entirely accurate. With manual focus lenses, the only focus point available to you is the centre one.

Have you tried haze/UV filters? I can't say that they will work in your scenario because I've never been at the pointed end of a commercial airliner, except Concord, but had no SLR handy at the time.

Haze/UV filters have to be good at something because they've never been any use to me in a hazy scene.

I've only ever taken pictures through the scratched 'n dirty plastic side windows of a Piper Warrior, so not really a parallel there.

I'd suggest trying a better lens, but do you really need the 18-250 range of the Sigma? Which focal lengths do you find you actually use?

Well yes, all that may be true, but it's still a good camera, possibly.