Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
05-02-2015, 09:28 PM   #1
New Member

Join Date: Apr 2015
Location: Plano Texas
Posts: 7
Help with high speed sync with LS lens


I got a 645z and the LS 135 lens. I am trying to get the High speed sync working reliably, anything above 1/60th! Unless I am badly mistaken, I tested the lens at all speeds and everything worked, at least once! Unfortunately, the exif information shows "F--" for shutter speed, so I can't go back and see that I wasn't just dreaming about it working at 1/60th, 1/125th, 1/250th, and 1/500th. I made sure the camera was set to "single frame shooting". According to the LS135 manual, the 645 automatically sets the cameras focal plane shutter to 1/8th, I switched out of LS mode and set the cameras shutter to 1/8th. I cock the lens, take the shot. 1/60th is rock solid, the whole frame is exposed, for testing purposes, I will re-cock the leaf shutter, change the leat shutter speed to 1/125th, some times, I will get the full frame exposed, other times, the top half of the picture is dark, and now, I never get more then a sliver of exposed region, with the top part being dark! I am suspecting the camera focal plane shutter? or I am missing some set up step, or setting?

Any help with be greatly appreciated!

05-02-2015, 09:51 PM   #2
Veteran Member
sterretje's Avatar

Join Date: Dec 2008
Location: Roodepoort, South Africa
Photos: Gallery | Albums
Posts: 3,561
I'm not familiar with the 645Z (or MF for that matter), but did you set the flash (which one?) to HSS mode?
05-02-2015, 10:08 PM   #3
New Member

Join Date: Apr 2015
Location: Plano Texas
Posts: 7
Original Poster
I am not using a speedlite, I don't have one with an external sync jack! I will be buying a Yongnuo HSS that comes with a 2.5mm external sync jack.

I plan on trying a different Flash, and different sync cables.

I am using studio strobes, it's a Novatron 1500vr. with a wired sync cable to the power pack.
05-03-2015, 06:49 AM   #4
Senior Member

Join Date: Dec 2009
Location: Münsterland
Posts: 131
I have bougt a little adapter for the hot-shoe with a hot-shoe. It has a short cable wich i connect to the LS-Lens. The flash is triggered via middle contact of this adapter.


05-19-2015, 04:16 AM   #5
New Member

Join Date: May 2015
Posts: 2
Hi white Dog. Any update on a fix for this. I have the same problem and that is using continuous light source so not a flash problem
05-20-2015, 05:19 AM   #6
New Member

Join Date: Apr 2015
Location: Plano Texas
Posts: 7
Original Poster
Hi Chris,

Could you elaborate on what you did? were you using the LS lens with continuous lighting and still got only a partial part of the picture exposed?

I got a new speed light with a 2.5mm sync jack to try, although more of the frame was exposed, it still did not work correctly! The sync cable I got is very loose
on the lens and will almost fall of if the lens in inverted! So I got another cable on order and will try it once it arrives.

If I ever get resolution, I will update this post for sure! There is another user here having the same problem and I asked him to be sure to update me if he gets a fix!
I am suspecting the camera body itself! but I don't know how to prove it!

Also , per sterretje suggestion, I forgot to set the new speedlight up as HSS, I will try that as well.
05-21-2015, 06:58 PM   #7
New Member

Join Date: May 2015
Posts: 2
Hi all - sorry for the change in user name - login issues!

I think I have solved this by placing some tape over the lens contacts so the camera goes into dumb mode. I then put camera into manual, set a shutter speed of 1/8 sec as per what is meant to happen in LS mode and then chose the aperture and leaf shutter speed on the lens. And presto - all works great.

A cheap fix and one that doesn't really change work flow too much.

Let me know if it works for you.

05-22-2015, 05:30 AM   #8
New Member

Join Date: Apr 2015
Location: Plano Texas
Posts: 7
Original Poster
Great new Chris!

So what do you think is not working correctly, the camera or the lens? it would be nice to get this working without having to have a work around! if it is the camera, maybe a new firmware revision can remedy the situation or do I need to get the lens repaired?

I will try this later when I get home from work!

thanks and regards,


05-22-2015, 06:54 AM   #9
Senior Member
johnsey's Avatar

Join Date: Mar 2008
Location: Fargo, ND
Posts: 113
I would venture to guess if you both have the same lens and body issue it isn't the fault of the Lens. Besides the connection is just meant to register if the focal plane shutter setting is engaged. Doing a quick search online it seams others have discovered the issue also on the 75mm LS.
05-22-2015, 10:39 AM   #10
New Member

Join Date: Jul 2014
Posts: 10
The tape fix also worked for me with the 75mm LS lens. Definitely seems like something that could be fixed with a firmware update.
05-22-2015, 07:04 PM   #11
New Member

Join Date: Apr 2015
Location: Plano Texas
Posts: 7
Original Poster
ok, the tape over the contacts also worked on my 135mm LS with both the speed light and studio strobes.

FYI, Salpardido was the other guy I mentioned, he said that he was working with somebody from Pentax. HE will let us know via this thread what they find!

  • 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, frame, lens, ls, pentax help, photography, plane, shutter, times, troubleshooting
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
High speed sync geoffw Troubleshooting and Beginner Help 18 09-21-2014 01:46 PM
Off Camera High Speed Sync theraven871 Flashes, Lighting, and Studio 21 04-29-2014 04:22 AM
High-speed sync Spodeworld Pentax K-30 & K-50 5 05-24-2013 06:33 PM
High speed sync flash with manual non-A lens? baby007 Flashes, Lighting, and Studio 45 10-23-2012 08:44 AM
high speed sync with K10 perstephone6 Photographic Technique 8 04-01-2009 02:03 PM

All times are GMT -7. The time now is 09:08 AM. | See also:, 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?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]