Third party flash unit on Pentax *ist DS

[el baroda]

Hi,folks. Has anyone used a 3rd party flash unit on his Pentax *ist

DS? I have a small generic auto flash unit for my old Pentax and

Ricoh SLRs. So far, this is only item in my "arsenal" that I have

not tried on my *ist DS, as I shoot mainly under available light. I

am attending an indoor function next month and I might have to rely

on a flash unit. Could someone please suggest a safe way to test

their compatibility. Or would using a 50mm f/1.4 lens with the

camera set at ISO 1600 be a better alternative? At the moment, my

budget does not allow buying a dedicated flash unit. Thanks a lot

in advance.

[readhaden]

I fire one or both of my old Sunpak 3600's with my istDS by jerry-rigging a "peanut slave" in front of the istDS flash, blocking off the istDS flash from spilling onto the object. The slave fires the strobe(s). However, I can set the 3600's to a given F stop and they will put out the appropriate amount light. Set the istDS to manual at the needed F stop and shutter speed (no more than 1/140 I think ... check the manual).

[Jochen_S]

I'm using my *istD with Metz and similar SCA flashes (for save Voltage - check yours) in autothyristor mode, either as main light source or to trigger my strobes. As far as I know there is no reliable dedicated flash around yet.

[el baroda]

Hi, Rich & Jochen. Thanks to both of you for your quick response. Actually, my main concern is whether or not it is safe (voltage compatibility) to use my old flash unit (Vivitar 2800)with my *ist DS. The manual recommends a specific Pentax flash model for this camera, but I'm not prepared to invest in a new flash at the moment. Best regards.

[martin_fahey]

I've tried a Metz 34 CS-2, and a Vivitar 283, both on automatic mode, with this camera, without any problems. The AF360FGZ is ideal for it, with P-TTL, but I have not looked for one yet, as I have an AF280T, which I bought to go with a Pentax Super Program. This gives TTL (not P-TTL), and works beautifully, with the *ist DS in auto or P modes.

[derekb]

I am much like Martin. I use both a Pentax dedicated AF-280Z and a Vivitar 285 Auto. The Pentax unit works great and the Vivitar I have tested at 8.5 V. I understand this is a bit questionable on Canon bodies as they are fussy about anything over 6 V but as far as I can tell (Pentax seems to give conflicting stories) that the *ist DS should be fine for anything up to 25V (some have got stories from pextax saying 250V but I don't trust that). In any case even if it was closer to 6V I think you should be OK.

 

The next important question is what is the voltage of the trigger of your flash, and that I don't know, it can vary a lot even in a given model type of some manufacturers.

 

Pick up a digital multimeter from your local electronics store (you should be able to find one for less than $20) or borrow one and put the meter into DC Voltage mode and put one contact on the trigger (center of the shoe) and the other on the contact that is in the show mount slot (should be on one side or the other or both) and see what voltage it is.

 

I personally not knowing the "official" voltage that is max from Pentax (as I have tried to get it but with no response) wouldn't want more than 10V running through my camera.

 

Also a tip that messed me up the first time. Remember to set your camera in manual mode when shooting with a non-dedicated flash as your camera does not know that there is a flash attached and will not set sync speed. It will meter and pick a long exposure that will allow ambient light to expose the picture (as well as your flash) and you will end up blurring you picture. I know this goes without saying for those used to manual and auto flash but it messed me up as I was not used to my camera not noticing a flash.

 

Have fun.

[el baroda]

Good evening, Derek (it's night down here in Sydney). Thanks a lot for your advice. I'll surely follow it before I try my Vivitar 2800 on my camera. BTW, I have seen your photos. They are excellent. Thanks again and best regards.

[paul_noble]

I can't answer for the *isdDS, but I had a similar question when I got a Vivitar 283 to use with my Pentax ZX-60. I wrote an e-mail to Pentax support (on their website) and, while they wouldn't comment on whether a Vivitar flash would work on a Pentax camera, they did tell me that the ZX-60 should be able to handle a trigger voltage of up to 600 volts. I measured my 283 and it was around 23 volts.

 

If you send them an email, they would probably tell you the maximum trigger voltage for your camera.

 

Hope this helps.

 

Paul Noble

[el baroda]

Thanks a lot for the input, Paul. Will send Pentax an email. Best regards.

[ivo_miesen]

The Vivitar 2800 is a flash with one of the highest trigger voltages. I wouldn't risk my istDs on that.

I am completely satisfied by using a fairly standard Metz flash, the 36C2. It's still produced so you could buy it via your local camerashop. With an adjustment of 0,5 stop it works excellent.

But still I prefer to set the ISO to 3200 and use my 1.2/55 Porst lens, available light beats any flash.