Short answer: yes.
Long answer: until now I have always had enough cord-length to connect my Pentax 135 mm leaf shutter lens directly to the studio flash, but I promised to check whether the wireless triggers I own (Pocketwizard Multimax) were fast enough to be used with the 1/500 x-sync of the LS lens, also because I wanted to know myself whether it would be a viable option to trigger wirelessly, should the need or want arise.
The setup:
A fast shutterspeed with flash is handy for two reasons:
1) Freeze motion of a model (less ghosting).
2) More leeway balancing natural and artificial light.
The second point is illustrated by my test shots below, the shorter speed allows for less blown-out windows and backlit table surface by the natural light.
After shooting this it occurred to me that it was not very clear whether the flash still resulted in exactly the same amount of light on the subject (even though the artificially lit parts were still somewhat correctly exposed), so I setup a shot later when it was dark, see below. This is 100% flash light (without flash the image would be black). Shown is a crop of the image (near center), with some solid blacks and some blown-out whites, uncorrected of course. The results are good enough for me, exposure seems to go slightly down from 1/60 to 1/500 but this is also the case when I connect the cord (last image), so that is probably due to other factors than the triggers and easily corrected, the effect seems tiny. Pocketwizards Multimax: pass. Leaf shutter: rules.
I know this is over 4 years old but I wanted to confirm you were triggering the lens leaf shutter with the flash sync cord (PC cord) and wirelessly with the Pocket? What was the camera set to? Bulb? Could you show some comparison shots? 1/60 leaf shutter to 1/60 plane shutter, with and without flash.
Hi Jess Vincent, it is the other way around: the camera makes the leaf shutter fire (it automatically recognizes the leaf shutter and sets itself to LS, see: https://www.joerivanveen.com/blog/smc-pentax-645-ls-14-135mm/) and at that exact moment the flashes need to fire (not at the moment you press the shutter, which is significantly sooner). That is where the pc connection on the lens comes in: it fires when the leaf shutter fires. The camera has to prepare for the leaf shutter (open the plain shutter, fire the lens mechanically) and so doesn’t “know” when the leaf shutter will be open. This means you connect your flashes or your wireless trigger system to that connection on the lens instead of the one on your camera. The object of this test was to see whether the wireless communication (and my flash…) was fast enough for 1/500th of shutterspeed. At 1/60 there is no difference between the leaf shutter and the normal shutter. Hope this helps?
Kind regards, Joeri van Veen
Hi Joeri,
Thank you for taking the time to write such a great test of the 135mm pentax leaf shutter lens.
I just purchased an Pentax 645z and I was wondering if it’s worth buying one of the old LS lenses.
Do you know if the Pentax 645z also sets itself to LS and if it syncs properly all the way to 1/500s?
Have you also tried the Pentax 645 75mm LS lens?
Hi Igor, thanks for getting in touch. The 645z should set itself automatically to LS mode and sync correctly as well from the info I have, but I can’t confirm that from my own experience because I never used one. Also never been able to source a good 75LS for a decent price here. That said, the 135 was perfect for my needs so I didn’t really look hard.
Also, check when you buy one if the shutter cocking ring still feels light, mine needed to be pulled rather hard which indicates it might need servicing. (Worked well for a couple of years though but still something to consider.)
If you get one and it works as it should on your 645z can you please confirm? I will add that information to this post then.
Kind regards,
Joeri