Probably a combination of things... the lens was second hand, and I had it stowed away for a few months in a lens pouch. Unfortunately I think the pouch had been damp at some time (though not immediately prior to storage I hasten to add) and I should've thoroughly dried it out.

Maybe I'll never know exactly what went wrong

It's been kept isolated in better conditions and the fungus doesn't appear to have grown anymore - and thankfully it's on the periphery. I got hold of a 50-200 to replace it (which is a great little lens), but the 80-320 still gets used from time to time.
Matt

Nope. The K100D is a great camera. The shake reduction will be a very good addition for the 80-320mm. The sensor is the same as in all the Pentax 6mp DSLRs - with good technique and workflow (it could take you a little while to master) you'll get superb results.

I've used the 80-320 on the *ist-D and have some great shots. I normally used it on a carbon fibre monopod to cut down camera shake.
e.g.
http://www.ephotozine.com/u16488/gallery/427669
http://www.ephotozine.com/u16488/gallery/408335
http://www.ephotozine.com/u16488/gallery/218487
http://www.ephotozine.com/u16488/gallery/218487
http://www.ephotozine.com/u16488/gallery/181657

The last one shows what a lovely bokeh the lens has (out of focus highlights).
I use mine a little less now only because it's growing some fungus (Boo hoo!)

Hope that helps!
Matt

I've used the JetTec inks in an ancient Photo 870 and they seem just fine (at least for everyday use).
Got them from picstop.co.uk
Matt

But for the Canon users, the Pentax lenses just aren't up to it

As an aside... a good friend of mine has a Canon 20D and a set of L lenses and a couple of Sigma EXs. All very nice, but unbelievably heavy! Went on a day out and I had 12mm-200mm covered in Pentax (12-24, 16-45, 50-200, 50/1.4), with Lee filters in a tiny Pentax shoulder bag. Could lift it with ease. His eyes nearly popped out of his head when he felt how light it was - I needed two hands to lift his equivalent kit

Sooooo, you could always fit the battery in the body, and get a solid piece of lead for the battery in the grip They'd love it then

Matt

Could be the Ricoh mount - which was very very close to PKA.
However, be warned, some Ricoh mount lenses will go on but are a right royal pain to get off again

If you've already got the 18-55 kit lens, I'm not sure why you'd want to try such a cheap lens...

Matt

I've locked this, as it's a duplicate of here:
https://www.pentaxuser.com/forum/viewtopic.php?t=4564

Will delete in time
Matt

I always cradle the lens in my left hand, and support the base of the body with the palm/wrist - even with a diddy 50mm lens on!

Don't often need a tripod... especially with the K10D's SR
Matt

Pete,
There's a 16-45 listed on www.ephotozineshop.com under the Bargain Basement items
Pretty excellent price too... maybe your wallet will be even lighter
(Ring 'em quick)
Matt

I can only comment from memory...

I've had both the A and F versions of the 28mm/f2.8. I think they are identical optically. Both produced a very sharp image and had the usual Pentax colour etc.

However, I was comparing them to the 16-45/f4 and I much prefer the 16-45. The bokeh is better (8 aperture blades compared to 6 on the 28mm and 18-55), and I couldn't tell any difference in terms of sharpness.

If you can pick up one cheaply, then it's probably worth a try. Personally I found a zoom more convenient as I found 28mm isn't wide enough for general use on digital.

HTH!
Matt

Tyr,
That's not quite the point... 10mm in fisheye equates to 180 degree angle of view. (It's an "equisolid angle projection" fisheye, FWIW)

10mm in rectilinear equates to about 110 degrees.
No rectilinear could ever get to 180 degree AoV

(That's all in the APS-C domain of 23.5x15.7mm)

See this link: http://photo.net/learn/fov/

Matt