[gurtch]

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This grey 1.4X is listed on ebay, but not in the data base. Anyone know anything about it? Which lenses will it fit? I just purcheased a 500mm f5.6 67 lens, and was wondering if it would fit.
Thanks in advance. Here is the ebay link:
Gray Pentax 67 1 4X Rear Converter 1 4X Pentax 6x7 67 MLU 67II 027075028890 | eBay

Dave in NJ

[Thomas]

Hi Dave:

I have the 500mm and the 1.4x and they work quite well together.
Just curious, how much for the 500mm?

Tom

[rob1234]

Never used it, but The Internet says it's excellent.

[gurtch]

Tom: I paid $930 for the lens in 9 out of 10 condition (have not received it yet). I plan on using the 500 and maybe the 1.4X with a Pentax adapter, and 645D
Regards and thanks all.
Dave

[gurtch]

Thanks all. I hope this works. I purchased on eBay the 500 mm f5.6 and 1.4 X extender to use with an adapter on a 645D. I know a 500 mm lens is a 500mm lens, but this lens was designed to cover a 6x7 negative. I will be essentially "cropping" the center with the 645D. What would be the "crop factor" ? In other words, what would the equivalent focal length be?
Thanks
Dave
PS: will let you know how this works out....my intention is to try this combo for wading birds.
Dave

[Thomas]

Dave:

You're correct, 500mm is 500mm regardless of the format; however, the field of view or crop factor depends on the sensor or film size. In 35mm equivalents, a 500mm is about 400mm on the 645D (0.8 factor). Using the 1.4 turns the lens into 700mm, or in 35mm terms, about 560mm.

I hope all is back to normal at your home.

Tom

[672]

I use the 1.4 xt. on the P67 400mm EDIF. Its a really good extender but still looks a lot better (in prints) when the lens is stopped down a full stop. So for your new 500mm lens that puts you at an 11 stop.

The issue with xtenders on slow glass, for me, is that focus becomes very hard to judge even in bright sunlight.

Also, if anyone else is lusting after the 500mm , there is one at a shop near me, new in original packaging. They asked 2K for it and i offered 400, needless to say its still in the shop. I wasnt very motivated since i have the 400mm already. PM me if you want to find the lens.

[672]

this converter is actually reviewed on pentax forum, but its got the wrong picture posted.

[gurtch]

Thanks all. We were homeless for 6 months from Sandy, but are now back home!
Dave Gurtcheff
Beach Haven, NJ

[desertscape]

The gray 1.4 is a newer design than the older black T6 2X. The 1.4X uses five elements and is very well corrected. It will not cause image degradation. Any softness seen when using it is from the prime lens. Converters magnify aberrations from the prime lens, so using the prime lens wide open is not advised. The 1.4 will not fit the two zooms, the 150 Takumar, the 165LS, the 105mm or the wide lenses. It will fit the 200 Pentax and longer lenses. It even fits the outer bay lenses. Combined with the 200 Pentax, the 1.4 seems to be as sharp as the 300 ED.

[bull drinkwater]

i have a 300mm 67 lens plus a 67 to 645 adapter, i use it with my 645 1.4 and 2.0x teleconverters with no problems.