Yes you can use P-TTL both on and off camera.

The zoom setting is entirely independent of the P-TTL protocol so picking a length manually will make no difference to the metering (which is what P-TTL is concerned with), just to the angle at which the light leaves the flash head.

The only thing you can't use is the automatic zoom when the flash isn't directly connected to the camera. That's when you want to set it manually according to the subject and the position of the flash (experiment and adjust to taste).

If you really feel the need to have the light narrower than the 85mm setting provides, then you can make your own DIY light modifiers by wrapping some tin foil around the head with a progressively narrower gap at the front to let the light escape - I think you'll find the 85mm setting will be just fine for most uses though.

I've never used one but I'd imagine the (comparatively) low output would only be suitable for subjects that were very close to the lens. I'd be interested in your findings if you do buy one though!

If you leave it in auto (mounted on the camera) it will select the narrowest angle (85mm) anyway, so no need for a manual override. When using the flash off camera it'd be worth experimenting with manual zoom settings to see which suits the subject best - if I'm bouncing it off a ceiling then I tend to have it set to the widest angle, if I'm aiming it at the subject then I use the narrowest to get a little more direction to the light. From memory I think it defaults to the widest setting if you leave it on auto and use it wirelessly.

Nice find Clarky! Even if the Bronica body was broken beyond repair (doubtful) then there's still a lot more tha £1200's worth of kit there - go for it!

Excellent judging Aiki and thanks for my Special Prize! There isn't really any detail to see in that paper, it's just a sheet of regular photocopier A4.

Well done to Prieni - loved the patterns and the colours so a very worthy winner.

Well I was wrong! Ended up going very cheap and I wish I'd had a bid myself now...

I've seen transparent cameras before but I don't remember seeing a transparent lens. Makes me wonder if it's actually useable or whether there'd be stray light spoiling things?

Now that's one I haven't had pass through my hands before!

I wonder if that was some sort of display model for dealers?

He'll be searching eBay for A50's by now...

We did get a little sidetracked though - sorry OP!

Good idea! I've got a clear plastic tube that would probably do the job but I wasn't quite sure where I'd find a convex mirror from.