Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-09-2014, 02:13 PM   #1
Inactive Account




Join Date: Jan 2011
Posts: 440
Sammy 16mm f/2.0 INF dead stop adjustment Rokinon Bower Samyang

Has anyone adjusted the infinity dead stop on their Samyang / Rokinon / Bower 16/2.0 ??

I found these instructions for the (similar) 14mm/2.8:

Como calibrar el enfoque del Samyang 14mm. How to fix focus of Samyang 14mm | | VideofyMe

photo-worX.de - Samyang 14mm Reparaturanleitung

The 16 looks to be a similar IF design, would really LOVE a dead stop at infinity, I'm sure not the only one!~

03-09-2014, 04:29 PM   #2
Site Supporter
Site Supporter
Just1MoreDave's Avatar

Join Date: Feb 2007
Location: Aurora, CO
Photos: Gallery | Albums
Posts: 6,340
I would try using the moon as a target for infinity focus. The focal length means looking for details in other targets is hard, but the moon in a dark sky has sharp edges that should work.
03-09-2014, 05:51 PM   #3
Inactive Account




Join Date: Jan 2011
Posts: 440
Original Poster
Thanks Dave, this is why I'd like to have a dead stop at infinity - as nature intended!
03-10-2014, 02:22 AM   #4
Pentaxian




Join Date: Jan 2013
Location: Near Vienna, Austria
Photos: Gallery
Posts: 2,067
QuoteOriginally posted by digital029art Quote
Thanks Dave, this is why I'd like to have a dead stop at infinity - as nature intended!
I think there are two different things involved that we should try and keep apart. First, at least with older lenses, there were many reports about badly adjusted focusing scales that were obviously off. This could, and should, be adjusted. On my copy of the 16mm, however, this is not the case. There is an infinity mark that is (almost) exactly where infinity is (at normal temperatures). But the hard stop is a little further. This appears to be intentional. Maybe the infinity setting changes with temperature or other factors, as it does with long tele lenses, which have a similar "floating" infinity setting. The 16mm also has a complicated focusing mechanism with the front and back lens groups moving in opposite directions. I'm not sure if it is a good idea to meddle with these things.

03-10-2014, 01:04 PM   #5
Inactive Account




Join Date: Jan 2011
Posts: 440
Original Poster
Thank you wkraus. Based on my experience with other Sammy lenses, infinity is always off. I think this is labor saving on Samyang's part - there seems to be no calibration done at the factory. They assemble the lens and let the end user find infinity! Some of their designs, like the 8mm/3.5, which is a real old-school focus helix - very easy to adjust (reset) properly. The 14mm is an IF design and is a little more complicated to set properly. Certainly allowance for temperature changes is only necessary for telephoto lenses, it's not needed on a 16mm!!

What I'd like to know is if anyone has already adjusted theirs - it's got to be very similar to the 14!
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!
14mm, 16, 16mm, 16mm f/2.0 inf, 2.0, adjust, adjustment rokinon bower, bower, infinity, k-mount, pentax lens, rokinon, sammy 16mm f/2.0, samyang, slr lens

Similar Threads
Thread Thread Starter Forum Replies Last Post
What are best deals on 16mm F2 from Rokinon, Bower and Samyang? Casion Pentax SLR Lens Discussion 6 01-05-2014 09:23 AM
Samyang 16mm f/2.0 vodanh1982 Pentax News and Rumors 60 08-01-2013 10:16 PM
Sammy 800/8 mirror lens on Q (Bower Rokinon Vivitar Opteca .. etc) any Samples ? digital029art Pentax Q 6 02-21-2013 03:00 PM



All times are GMT -7. The time now is 01:06 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