Got caught in horrendous weather in Vollendam this year - rain spottles everywhere
http://www.flickr.com/photos/28204187@N08/5143257355/in/set-72157624888537241/

Am I better off keeping my Series A 50/1.7 & learning how to zone focus.

On a fine day using 400 ASA 35mm film a typical aperture would be F16.

At f16 on a standard 50mm lens the hyperfocal distance = 16ft, when the lens is focused on this distance - everything is in focus from 8ft (or half the hyperfocal distance) to infinity.
Source: Pentax ME Super Book of Photography by HAMLYN 1982, page 62.

So applying this example to our Pentax DSLR's with Auto ISO - we set the ISO at Auto, aperture to F16 (AP) & off we go - only remembering to click the shutter!

Algi,

Thanks for that - no need to panic then!

John,
Thanks for the reminder - I think I still have my Lens Catalogue which came with my Program A back in 85, I will have to find it - if only to reminisce the once great range of lenses produced by Asahi Optical Co., LTD.

Are there any 'long' 'Series A' manual focus lenses.

My 80-320mm FA really struggles to focus with moon shots & other long distance efforts - you can't set the lens manually to infinity because it 'goes' slightly beyond (its just the way the AF lenses work). If I could find a manual focus lens I could also use my Manual/App Priority 'doubler' on it.
Best effort so far with 80-320:
http://www.flickr.com/photos/28204187@N08/5115534484/in/set-72157622606758962/

We went for a week in September - 1000 images later we returned - whew!
The Tropen museum lets you take pics inside - first time I have used the Museum setting!
I took the big zoom with me - it came in useful at the ARTIS Zoo.
One of the Pottery shops told me off for trying to take pics of Delft ware - their loss since its not on FlickR!
A glass ware shop also scowled a bit.
We also took 2 Fuji compacts, our first hols without a 35mm film camera since the early 80's.
Here is my expanding set - not all perect & the weather was against us most days
http://www.flickr.com/photos/28204187@N08/sets/72157624888537241/

ps just remembered - you can take a camera around the BOLS Experience

Nice pick & timely - Classics Cars mag has published an article on the JAP engine in the latest edition.

My 80-320's sharpness seems ok at the short-end but struggles beyond 280 or so, but I thought this was due to my lack of experience (not using monopods/tripods etc) with 'long' lenses. If there is a fix I would be interested to hear more!
I could ramp up the asa to 1600 or the shutter speed to 1000th but I can't do this when taking pics of propeller driven aircraft. Someone link recently posted some cracking shots on FLICKR using the 300 digital prime but the cost is out of reach to many.
My 80-320 stuff ( http://www.flickr.com/photos/28204187@N08/sets/72157622639681232/ )

I still have a roll of Fujichrome Sensia 200asa in my Pentax ZX-M which gives surprising results given its simple metering.
My last big trip with the ZX-M was to Sorrento in 2008.
My scans from slides (done by the 'new' Fuji Lab) are here (though resized for Flickr):
http://www.flickr.com/photos/28204187@N08/sets/72157623109209463/

Also you can't beat a family slide show - my dad has even managed to find a medium format slide projector which gives amazing results from his 1950's CT18 slides. He even tried a modern Fujichrome film in his old camera (non-slr, manual everything - its got bellows!) a while back and the results were still brill!

Sorry folks, problem sorted - the exposure bracketing feature was turned on (not sure how) & I didn't notice anything on the LCD, its only when I checked my recent shots of bluebells that I realised 6 different shots had a mixture of three levels of exposure??
I will put the usable ones on Flickr when I have a spare minute, Lol!
Sorry about any confusion caused by my errors.

Cheers John