I'm looking at a Pentax SMC Manual Stop Down 500mm F4 lens. If I purchase it I plan to use it on a 645n (with adapter)> Does anyone know what this lens is like? I would probably be shooting it wide open so performance at that aperture is important to me. What is the minimum focus distance. Can any one out there help...tks...jim

-- Jim Vanson (primary_colors@hotmail.com), March 26, 2000

Answers

The 500mm is an f/5.6 with an automatic diaphragm. Did you mean the 600mm or 400mm? SR

-- Steve Rasmussen (srasmuss@flash.net), March 27, 2000.

I've never heard of an f/4.5 500mm either. Obviously, the seller doesn't know his lens very well. I would avoid this seller given what has happened so far. SR

-- Steve Rasmussen (srasmuss@flash.net), March 31, 2000.

Actuall, someone has a 500mm f4 lens for Pentax 6x7 on the ebay auction at the moment. He describes it as a rare lens. Check it out.

-- Tony Wood (awood@telus.net), March 28, 2000.

If your shooting a 645 then I would recommend the 600 5.6. Its big, heavy and fairly expensive but you can find them used, usually in great shape. Awesome glass... can be had for around $2800 to $3000. If you can swing it you wont be sorry...

-- Scott McKinley (srmfilms@aol.com), March 30, 2000.

I have been intrigued by this discussion to the point that I called Pentax and waited for 15 minutes while they tried to find some info on this product. I was told that they NEVER produced an f4 and the current 500 has been around since 1979. I also emailed the Ebay seller to find out if it's an actual Pentax designed for the 67 and not something modified. I have yet to get a response.

-- Rolf Strasheim (rolfs@ionet.net), March 30, 2000.

I was curious about this lens too and emailed the eBay seller. He insists it is a 500 f4, and sent photographs. The lens is in a box that says Pentax. It looks to be in the style of the 600/4 and 800/4, but it doesn't seem to be as fat as the 600/4. It's not in any of my literature, but there is a definite family resemblence to the other big Takumars. Bob

-- Bobby Mahaffey (mahajen@prodigy.net), March 31, 2000.

Thanks Jim, about the update. When I got your message I also got a message from the eBay seller mentioned above. The lens is not a 500/4 after all, but is a 500/4.5. The box says "Asahi Pentax" with some smaller writing that I can't read. The seller has posted the change in f-stop in his eBay ad. So, has anybody heard of a 500/4.5?

-- Bobby Mahaffey (mahajen@prodigy.net), March 31, 2000.

Bob; the Pentax SMC 5004.5 lens is of course the model made for 35mm SLR, and not for the 645 or 6X7 models. I have a mint Pentax 500 4.5 and use it on my Pentax LX and Pentax PZ1p SLR's. Regards, Tony.

-- globetrotter (globetrotterworld@ukonline.co.uk), April 27, 2001.