Paul C. Buff, Inc. Technical Forum

Before I start on this DIY project, I want to see if anyone has yet to succeed at it.

If you know the Speedotron 105, it has 4 straight tubes; they are almost 6 inches long.

The ID of the Speedotron adapter is about 4.5 inches, similar to the Elinchrom mount ID.

My plan is to extend a Speedotron mount with four posts to connect it to the PLM Elinchrom mount so that the PLM shaft mounts about 3 inches away from the end of the tubes.

Hopefully I can create a rigid mount without adding too much material between the tubes and the PLM.

Comments invited.

Aaron

I remember seeing someone do this...I think on FM or Flickr. I think they actually hacked a speedotron speedring onto the PLM speedring...

It won't work just attaching to the speedring because it won't clear the 6-inch tubes. I've seen one where they attached the PLM mount to a reflector, but that blocks too much of the light from the edges of the umbrella.

Aaron

The critical element in the PLM mounting system for your purposes, is the shaft that has a threaded end for mounting to the mounting "cage".

If you can fabricate a mount for the 105 that was sufficiently strong and positioned a quarter inch hold between the tubes, then you could mount the PLM shaft on your "cage" and adjust the tubes for optimum placement relative to the PLM.

Can you explain "between the tubes"? there is no room between the tubes, so I assume you mean centered or on-axis with the tubes?

I also don't know what you mean by adjust the tubes; what would be the adjustment mechanism?

Once I assemble all the parts I'll post a photograph of what it looks like.

Aaron

I hope this link works-

viewtopic.php?f=8&t=1125&hilit=Speedotron

That is the mod I mentioned in my OP, so thanks for the link. That is a 206 head, very different from a 105 head which has tubes that are twice as long and has 4 tubes instead of 1. Also he used a reflector, which I think will restrict the edges of the light too much.

Sorry if this is a dumb question, but why not just use the 7/8mm rod? The length of the flash tubes are going to prevent maximum focus anyway, so shifting the the rod a few inches off axis should not hurt anything, especially if the PLM is soft silver or white.

Oops. I think that's what I was thinking of. I had forgotten he used one of the newer heads.
No, it won't fit w/ that hack because the tubes are way too big on the quad tube head. You'd have to build up some other kind of mounting system yourself...maybe a speedotron ring off the beauty dish with some sort of bent metal rods connecting to a screw and you might as well build some way to shift the head in and out?

Your best bet is probably to just use the umbrella mount unless you have as much mechanical skill as Dave(tetrode)...

For some reason I thought the more centered, the better. Thanks for letting me know otherwise.