Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
10-12-2013, 12:38 PM   #31
Senior Member




Join Date: Jul 2008
Location: Annapolis MD (USA)
Photos: Gallery | Albums
Posts: 247
QuoteOriginally posted by drougge Quote
I have their 645 to K adapter. It also mounts the lens slightly rotated. This has never bothered me, because I don't have any lenses with non-rotating feet.

What has bothered me with it was internal reflections. It really needed to be flocked. After doing that it was fine. (Originally I used a piece of black sock, later I bought flocking material on ebay. Performance was fine with the sock too.)
Thanks for the input.

10-12-2013, 12:41 PM   #32
Senior Member




Join Date: Jul 2008
Location: Annapolis MD (USA)
Photos: Gallery | Albums
Posts: 247
Moved up to genuine Pentax adapter

Hey, guys-

My search for a workable solution to the 400mm f4 6x7-to-K Mount setup continues.

I purchased a used-but-like-new genuine Pentax adapter from KEH. Does anyone know what the function of the little threaded knob on the side of the adapter? Looking inside, the knob location seems totally blank.

What could its function be?

Sig

Last edited by Sigmoid; 10-12-2013 at 12:44 PM. Reason: Fixed typo
10-12-2013, 06:10 PM   #33
Senior Member




Join Date: Nov 2008
Location: Maine, USA
Photos: Gallery
Posts: 250
QuoteOriginally posted by Sigmoid Quote
Hey, guys-

My search for a workable solution to the 400mm f4 6x7-to-K Mount setup continues.

I purchased a used-but-like-new genuine Pentax adapter from KEH. Does anyone know what the function of the little threaded knob on the side of the adapter? Looking inside, the knob location seems totally blank.

What could its function be?

Sig
When used with 67 lenses with a built-in tripod mount, this adapter allows the camera to change its position vertically or horizontally while the lens remains on the tripod.
10-12-2013, 08:47 PM   #34
Senior Member




Join Date: Jul 2008
Location: Annapolis MD (USA)
Photos: Gallery | Albums
Posts: 247
QuoteOriginally posted by nightfly Quote
When used with 67 lenses with a built-in tripod mount, this adapter allows the camera to change its position vertically or horizontally while the lens remains on the tripod.
Thanks for the information!

Yes, I see! I finally got enough hardware pulled together to mount it on my HD Feisol tripod and discovered how it works.
Unfortunately, the large diameter of the focus ring makes it really challenging to make the lens fit on my new Wimberly-knockoff gimbal head so I'll have to address that issue next.

Sig

10-13-2013, 08:21 AM   #35
Junior Member




Join Date: May 2011
Posts: 32
External Bayonet Question

I recently acquired the 6x7 Bellows. It uses the external bayonet to attach to the camera. This is my first piece of equipment that uses the external bayonet.

I have a cheap 6x7->K adapter but it only uses the internal bayonet.

I bought a better quality 6x7->K adapter from KEH that has flanges for external bayonet but its locking mechanism doesn't work with the bellows, so my K-mount camera ends up rotating freely when mounted to the bellows. Not a good idea.

The bellows seem to need the locking mechanism where the locking pin protrudes through the mount, just like the camera body does. However, the second 6x7->K adapter I bought seems to release via a little button on the side of the barrel, like the auto extension tubes (for inner bayonet) do. Ironically, the first 6x7->K adapter I bought does have the locking pin, but lacks the external flanges.

Does anyone know of a 6x7->K adapter that has both the external flanges and the locking pin that works like the camera body does?

Thanks,
Sterling
12-17-2019, 07:59 PM   #36
New Member




Join Date: Nov 2019
Posts: 7
The only reason I am thinking about doing it is to save weight. My lens is so heavy already, and an ME Super would not be much to add to it. An 67ii is certainly a lot heavier.
12-18-2019, 12:02 PM   #37
Site Supporter
Site Supporter
gofour3's Avatar

Join Date: Oct 2008
Location: Vancouver, Canada
Posts: 7,716
QuoteOriginally posted by sbjornda Quote
I recently acquired the 6x7 Bellows. It uses the external bayonet to attach to the camera. This is my first piece of equipment that uses the external bayonet.

I have a cheap 6x7->K adapter but it only uses the internal bayonet.

I bought a better quality 6x7->K adapter from KEH that has flanges for external bayonet but its locking mechanism doesn't work with the bellows, so my K-mount camera ends up rotating freely when mounted to the bellows. Not a good idea.

The bellows seem to need the locking mechanism where the locking pin protrudes through the mount, just like the camera body does. However, the second 6x7->K adapter I bought seems to release via a little button on the side of the barrel, like the auto extension tubes (for inner bayonet) do. Ironically, the first 6x7->K adapter I bought does have the locking pin, but lacks the external flanges.

Does anyone know of a 6x7->K adapter that has both the external flanges and the locking pin that works like the camera body does?

Thanks,
Sterling
The original Pentax 6x7 to K-Mount adapter will have both the inner and outer bayonet mounts.

https://www.manualslib.com/manual/499030/Pentax-6x7-Lens-Adapter-K.html

Phil.

12-18-2019, 04:43 PM   #38
Loyal Site Supporter
Loyal Site Supporter




Join Date: Oct 2018
Location: Quebec City, Quebec
Posts: 5,110
Here is a picture taken with a K5 mounted on a 645 FA 400 mm f/5.6. The sensor being APS-C with a magnification factor of 1.5X, the result is similar to using a 600 mm lens on Full-Frame.

12-20-2019, 05:54 PM   #39
Loyal Site Supporter
Loyal Site Supporter
cobbu2's Avatar

Join Date: May 2013
Location: North Potomac, MD
Photos: Albums
Posts: 1,233
One advantage of using MF lenses on DLSRs is that the 6x7 lenses can be shared when traveling with both types of bodies thus saving space, weight and redundancy. I have a forthcoming Yellowstone trip next summer and plan to bring both my P6x7 and one of my Pentax APS-C bodies (either the K-3ii or my newly-acquired KP).

Here's an example using the SMC Macro-Takumar 6x7 135/4 on my K-5:

Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, medium format, pentax, pentax k-mount
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Looking for a Pentax 6x7 adapter to Hasselblad mount... Shingoshi Pentax SLR Lens Discussion 0 11-30-2009 02:11 AM



All times are GMT -7. The time now is 11:43 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top