Forgot Password
Pentax Camera Forums Home
 

Showing results 1 to 9 of 9 Search: Liked Posts
Forum: Troubleshooting and Beginner Help 02-18-2019, 07:07 PM  
SD card problem with K70
Posted By E-man
Replies: 9
Views: 532
The trick is to respond rather than react. And remember to BREATHE!
Forum: Pentax SLR Lens Discussion 01-22-2019, 07:16 AM  
Trouble about 135mm M42: any suggestion please
Posted By renix
Replies: 23
Views: 928
thank you all for your valuable advice, at this point I think I'll look for a Jupiter 37A
Forum: Pentax SLR Lens Discussion 01-22-2019, 05:48 AM  
Trouble about 135mm M42: any suggestion please
Posted By BigMackCam
Replies: 23
Views: 928
The Jupiter-37A performs very well indeed in terms of chromatic aberrations. I don't think you could reasonably expect better performance from any vintage 135mm lens within your budget :)
Forum: Pentax SLR Lens Discussion 01-22-2019, 01:41 AM  
Trouble about 135mm M42: any suggestion please
Posted By BigMackCam
Replies: 23
Views: 928
I also have both. My MC copy definitely has better flare resistance, which helps with contrast in strong lighting. But I'd happily shoot with either MC or non-MC versions :)
Forum: Pentax SLR Lens Discussion 01-22-2019, 01:14 AM  
Trouble about 135mm M42: any suggestion please
Posted By BigMackCam
Replies: 23
Views: 928
There are plenty of good options at this focal length, and quite a few within your budget. One that you might consider is the Russian Jupiter-37A 135mm f/3.5 (ideally the "MC" multi-coated version). It's a really nice, sharp lens with smooth out-of-focus rendering. Depending on condition, you could pick one of these up for around half your budget. Quite a bargain given the optical quality...

EDIT: I see @RedTurian beat me to it :p I'd agree that the Jupiter-11A is also well worth considering, though my personal preference is the 37A. But it's subjective... They're both very good indeed :)
Forum: Pentax K-70 01-08-2019, 05:37 AM  
Split focusing screen compatibility w/K30
Posted By UncleVanya
Replies: 10
Views: 627
Forum: Pentax SLR Lens Discussion 12-20-2018, 10:49 AM  
Zenitar and mounts
Posted By Ontarian50
Replies: 5
Views: 651
Sounds like a job for Leitax.

They are the experts in providing conversion kits so older lenses can fit new mounts. However, their main interest is in fitting old Leica R mount lenses, or Zeiss Contax manual lenses to newer mounts - including cinema mounts like the Arriflex.

I would think that if there were enough interest in such a conversion, it would be simpler and easier for Zenitar to just make the K mount available in the first place.

The only reason the lenses used to be available in K mount, was they made a camera in K mount when the old M42 became obsolete - just like Pentax did.
Forum: Pentax SLR Lens Discussion 12-20-2018, 05:02 PM  
Zenitar and mounts
Posted By RKKS08
Replies: 5
Views: 651
Adapting across different mount systems has three limiting factors:

1. Obviously the mechanical differences of the bayonet or thread mount.
2. The register distance (the distance between lens mount and sensor/film plane for which you will get a sharp picture).
3. The diameter of the mount.

Generally it is easiest to adapt a lens from a system with a bigger register distance to a camera system with a smaller one. The bigger the difference, the more space you can use for the construction of the adapter.
If the register distance of the lens is smaller than that one of the camera, a glassless adapter would - at least - make a normal lens a macro only lens, and probably cause vignetting.
If the register distance of the lens is equal or nearly equal to that one of the camera, adapting sometimes is possible - if the diameter of the lens is smaller than the diameter of the camera system. That's why the M42-PK adapters are working. And this possibility also depends on how deep the lens will produde inside the camera (mirror damage possible).

Register distances are
Canon: 42.00 mm
Pentax K: 45.46 mm
Nikon F: 46.50 mm

So most SRL/DSLR lenses can easily get adapted to Canon and mirrorless systems (including rangefinders), but not vice versa.

Register distances and diameters you can find in the net, that's one:
Camera Mounts Sorted by Register
Forum: Pentax SLR Lens Discussion 12-20-2018, 05:36 PM  
Zenitar and mounts
Posted By stevebrot
Replies: 5
Views: 651
Agreed. The 85mm f/1.4 and 50mm f/1.2 appears to be AIS with full manual diaphragm and should not be too hard to adapt.



Yes, one would think. KMZ still sells M42 and K-mount versions of the 16mm fisheye, so the tech has not been completely retired.


Steve
Search took 0.00 seconds | Showing results 1 to 9 of 9

 
Forum Jump


All times are GMT -7. The time now is 07:00 PM. | 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