Is it possible, without much work, to utilize a Pentax 645 lens with my graflex? A friend has given a couple of these to me and before I put them on Ebay I thought I would see if they were compatible with my crown.

Thanks,

Mike

Quote:

On 2005-01-12 22:45, weemster wrote: Is it possible, without much work, to utilize a Pentax 645 lens with my graflex? A friend has given a couple of these to me and before I put them on Ebay I thought I would see if they were compatible with my crown. Thanks, Mike

Yes, it's possible. "not much work" would be up to how creative you are!

But your Crown is probably a 4x5, correct? Those lenses will only cover 2x(2 or 3), not 4x5. Fine if you're using a roll film back or don't mind a circular image

The next problem would be that they're probably in the short range, 50mm to 100mm or so. How well they work would depend on how short they are. You'd have a bit of trouble trying to use a 50mm...

The big problem is probably in the mounting. Crowns don't do well with temporary cardboard lensboards and these lenses may not be worth buying and drilling real ones to fit?

But if someone gave me some lenses, I would sure 'play' with them before I got rid of them... Have some fun!

I know this doesn't answer your question but,at least, I can tell you how I use my 645 lenses. I bought a Medium format lens adapter for my 35mm Nikon. It is made in Germany by Zork. They are my best lenses for my Nikon! Harry

Quote:

On 2005-01-12 22:45, weemster wrote: Is it possible, without much work, to utilize a Pentax 645 lens with my graflex? A friend has given a couple of these to me and before I put them on Ebay I thought I would see if they were compatible with my crown. Thanks, Mike

Um, doesn't the 645 have a focal plane shutter? If so, lenses for it are not in shutter. Your Crown has no shutter. Get the picture?

Coverage is also a problem; lenses for the 645 won't come close to covering 4x5.

This is something I've wondered about for quite awhile, but I have the Pentax 6x7, with the lenses, I have for it. Since on the body, it's a set distance from the bayonet ring to the film plane. The long lens if use as manual barrel lenses, and could be fitted to a bayonet ring mounted on a lens board, for the Speed Graphic, might work. If the lens board bayonet ring was designed to accept lens on both sides, a 67 converter on the inside would double the focal length and f-stop, and if 67 lens extension tubes, or helicoid were used on the front would enlarge the image, and produce a larger image circle, Yes! or No? These lenses stop down to f/22 (55mm f/3.5, 105 f/2.4) & f/32 on three of my lenses. (135 f/4, 165 f/4, 200 f/4)

And there are two lenses Pentax made that have leaf shutters in them, ( 90mm. f/ 2.8 and 165mm. f/ 4 ) and the Soft 120mm. f/ 3.5 is click stop diaphragm, which would work the best as a view lens. And with Pentax''s inner and outer bayonet ring the 600mm f/4-f/45 (or 300mm. in a 35mm lens)

Now if a cable linkage to the Graflex shutter and bayonet ring all lenses would work in Auto, now all I need is some parts, and get my butt out in my machine shop. And a Pentax engineer's or users input. What did Fred Picker always say? Try it!!

These are some great lenses, not to be cross- usable !
Where's my pipe? I need to dream some more!

Quote:

On 2005-03-02 08:31, Tiltall ED wrote: This is something I've wondered about for quite awhile, but I have the Pentax 6x7, with the lenses, I have for it. Since on the body, it's a set distance from the bayonet ring to the film plane. The long lens if use as manual barrel lenses, and could be fitted to a bayonet ring mounted on a lens board, for the Speed Graphic, might work. If the lens board bayonet ring was designed to accept lens on both sides, a 67 converter on the inside would double the focal length and f-stop, and if 67 lens extension tubes, or helicoid were used on the front would enlarge the image, and produce a larger image circle, Yes! or No? These lenses stop down to f/22 (55mm f/3.5, 105 f/2.4) & f/32 on three of my lenses. (135 f/4, 165 f/4, 200 f/4) And there are two lenses Pentax made that have leaf shutters in them, ( 90mm. f/ 2.8 and 165mm. f/ 4 ) and the Soft 120mm. f/ 3.5 is click stop diaphragm, which would work the best as a view lens. And with Pentax''s inner and outer bayonet ring the 600mm f/4-f/45 (or 300mm. in a 35mm lens) Now if a cable linkage to the Graflex shutter and bayonet ring all lenses would work in Auto, now all I need is some parts, and get my butt out in my machine shop. And a Pentax engineer's or users input. What did Fred Picker always say? Try it!! These are some great lenses, not to be cross- usable ! Where's my pipe? I need to dream some more!

Not to be overly negative or dampen your enthusiasm, but the shortest lens that will for sure focus to infinity on a 4x5 Graflex is the 190 Ektar.