[pkr1979]

Hello all,

Im considering the 165mm f4 leaf shutter lens. I assume ttl works the same way with this lens as the focal plane shutter lenses, on a Pentax 67II in combination with a Pentax AF 500 FTZ flash?

Cheers
Peter

[kaseki]

Good question. I just skimmed the 500FTZ user guide and find no mention of the 67 or LS lenses. I am confident that when in the TTL mode, the camera will quench the flash when it gets enough light on the focal plane, which depends on flash timing. The 67 lens manual suggests that the LS lens works with flash. See page 21 on the lower right of this image.

[itsdoable]

I am skeptical that you will get ttl control with that flash, it uses the contacts in the shoe to trigger and quench the flash. The x trigger must be attached to the lens sync by a cable to sync with the leaf shutter.
The P5 cable only connects to the body. If Pentax made a split cable that connected to the lens sync pc and the body, you might be in business...
Please note I've only used the LS lenses with the older p67, not the II.

[pkr1979]

Thanks for the feedback. Im not sure how this would work either. TTL works fine with the regular lenses... the 500FTZ also have a 5P contact on the side of the flash, and maybe that could be used to trigger the shutter in the lens? While the TTL-communication goes through the flash-socket to the camera?

[pkr1979]

After some more research it seems to me that ttl cant be done with the ls lenses... which I find slightly frustrating. If I dont want to use an external meter, and do handheld ttl on camera flash photography I have to rely on the 1/30 sec sync speed (it would have been great if this could be done at faster shutter speeds). But how would those results be like... I assume Id need to use pretty small apertures to avoid other light sources then the flash and avoid motion blur?

[kaseki]

High speed sync (HSS) is the usual way of dominating sunlight with fast shutter timings, but won't apply to the 500 FTZ or the film cameras, as far as I know.

The 5-pin connectors bring the shoe connections to a cable that allows daisy-chaining the flashes. They can all work in TTL mode that way, and I've tested up to four.

If the 67ii is in TTL mode, then it should quench when it detects enough irradiance at the film plane. The flashes are all way faster than the fastest LS shutter time. What is unknown here is whether the flash turn on actuation at the shoe or 5-pin connector is guarenteed to occur during the period that the lens shutter is open. We need an LS lens manual to see what it says. Possibly, the 67ii was developed after the LS lenses and no update to their manuals was made to clarify this. A test may be needed.

[gofour3]

For TTL flash to work, bothe the camera and flash need to support it. When using the 165LS in leaf shutter mode, the lens fires the flash and not the camera. No Pentax LS lens supports TTL flash. So you are out of luck. In the focal plane mode TTL will work with the Af500ftz, 165ls and the 67ii.

Phil.

[pkr1979]

Its difficult to accept this, but at least I’ll save the money not buying the LS lens. It is possible to do trailing-shutter-curtain sync... then the shutter speed is 1/15 sec or slower. Does that mean I have to switch it from X to 1/15?

---------- Post added 12-02-21 at 02:29 PM ----------

Or, maybe it isnt. Whatever I set the sync switch button at (except sb), the lcd screen indicates leading-shutter-curtain-sync.

[garywakeling]

The LS lenses are designed to give higher speed sync with flash exposures. They use the X sync from the lens to fire the flash, unfortunately there are no electrical contacts between the lens and the body. It uses the aperture lever that normally closes the aperture to also release the shutter in the lens. With the 67II you can still use older style automatic flash however not with your current flash. The AF400T can be attached in place of the left hand grip with the dedicated handle and a synch cord connected to the X synch which will enable you to have "auto" flash using the flash's inbuilt eye to quench it once enough light has reached the unit. A little clunky in the modern world however you can get correct flash exposure with synch speeds up to 1/500th of a second at any aperture that the power of the flash can handle.
PENTAX AF 400T Bracket for 6x7 Camera reviews - Pentax Camera Accessory Review Database
PENTAX AF 400T reviews - Pentax Camera Accessory Review Database

The LS lenses still work well as "normal" lenses so if you need the focal length and the lens is nicely priced go for it. They were designed to help with shorter shutter speeds than 1/30th sec , good luck with your photos and on the hunt for your flash solution.

[itsdoable]

TTL flash works well with changing subject distance and lighting conditions, and primarily on subjects in the center of your frame. It is not everything. External sensors work pretty well as long as you have the lens set appropriately. Most studios (back in my time anyways) never used TTL when it was available, they wanted full control of the lighting.


The place where TTL was useful was weddings, where control of lighting was marginal. And after full automation came along, TTL fit right in.


The P67 LS lenses were very useful when you wanted outdoor daytime flash fill. They are a little awkward to use because you have to cock the leaf shutter as well as the wind the body each time.


My Hasselblad 500cx has a ttl sensor, but I can honestly say I've never used it. Flash control has always been manual, or with the sensor on the flash. But the 500cx is a very manual camera to start with.

[Abbazz]

Its difficult to accept this, but at least I’ll save the money not buying the LS lens. It is possible to do trailing-shutter-curtain sync... then the shutter speed is 1/15 sec or slower.

Just to mention that the Pentax 67165mm LS is among the best Pentax lenses available. It is superlatively sharp (which might not be suitable for portrait work), as well as distorsion and aberrations free. See the reviews here: https://www.pentaxforums.com/lensreviews/SMC-Pentax-67-165mm-F4-Leaf-Shutter-LS-Lens.html.

Cheers!

Abbazz