[APML] Two BIG-telephoto-lens-related questions

[Emmanuele Sordini <vega@ulisse.it>]

Hi folks,
I've run into a VERY big telephoto lens, a 500mm-FL (f/4.5) Pentax SMC. 
It's a little monster (weighs in at 3+ kg), it is about $800 used but in 
mint condition and comes with its original case; it originally had a Pentax 
bayonet mount that was subsequently converted to a Nikon one by a very 
skilled machinist. Now come the questions:

1) Is this lens any good for AP? I searched the 'Net extensively for some 
reviews/shots, but I found almost nothing. I understand this lens is not 
very common, but since it boasts a 11-cm objective lens, I've a hunch it 
could be profitably used for AP.

2) This may seem to be a dumb question, but have they ever made focal 
reducers (or other thingies that could be used as such) for such long 
telephoto lenses? I know that I could use a shorter FL lens, so it's not as 
much of an issue as it is with telescopes, where you can't have one for 
every potential need :-)) but I don't think I was the only one to ever ask 
this question.

Any thoughts/ideas/experiences to share?
Thanks in advance and clear skies from boggy Notherrn Italy,

Emmanuele 


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