Arca Swiss M2 Alternate DSLR Bag Attachment

[phero66]

I'm sure this is pretty simple, but could someone who owns a Arca Swiss M2 DSLR bag let me know how the bag-to-mount is affixed?  Ie: Is it a double plate design, on the front a lens to body mount screwed into an inner plate, epoxy, stitching, etc.  I've looked for user photos but all I see is with the camera body already attached to the bag.

I would like to modify the bag to take a Mamiya 645 or other MF camera mount, similar to the Cambo X2 Mamiya 645 Bag.  If someone with the DSLR bag for the M2 could send a photo of how the mount is attached that would be even better.

Thanks,

-John

[Rod.Klukas]

I believe that you could get this done as a custom mount from Arca-Swiss, but why?  Because of the depth of the body of a Mamiya/Phase 645 body or any other MF camera available, your lens choice would be severely restricted.  Probably 135mm or longer only.  That is why there is an MF conversion for the DSLR2 body to MF2 or a change to the RM3di or RM2d technical bodies.  This allows the use of the MF backs on these cameras.
So I think you are looking for automatic metering in a camera with movements. Schneider has some new tilt/shift lenses coming that might solve some of your goals. But again you are limited on the focal lengths available with movement.

 Another problem is that most bodies lose auto metering or all metering, when their own lenses are not used. So you might have only manual metering which can be ok, but slow.  A hand held meter and a tech camera is a better solution I think as they focus much better with the wise angle lenses anyway.

Hope this gives you some food for thought as you look at alternatives.

[phero66]

Hi Rod, thank you for the reply.  No I don't need automatic metering, simply I want to go past 1 second exposures without the further investment in either Schneider or Rollei electronic shutters.  And I want to control the exposure from the laptop in the Raw capture software.  I realize Schneider has a software product, and of course there are the paddles, but one more thing to have to carry and or keep track of software updates.

Using my DSLR and manual stop down on the Copal lens I would be limited to the 70mm Rodenstock HR, but my plan is to actually use the 90mm HR-W - which from reports has excellent coverage and would give me enough angle of view (when stitched) for all my applications.

On the 645 you say the 135mm would be the only one with enough flange to focal distance?  I don't need infinity
focus, just 13-15ft max usually.  Would I still not be able to reach my goals with this lens?  How much distance is lost from sensor to mount in the 645 body?

I don't mind the MF upgrade option, not trying to avoid it, simply need to figure out if I can get by with focal plane for both MF and DSLR or if I should buy electronic shutters now when I get the DSLR kit.

[phero66]

Well I found this helpful site: http://kzar.net/wiki/Photo/Montures

Looks like the Mamiya 645 distance is 63.3mm + 41mm (rough half distance to copal in lens) = 104.3mm
Need 93mm sensor to copal distance in the Rodenstock 90mm HR W @ infinity.  Ouch! 

Back to the drawing board for now.

[ChristopherBarrett]

Having that setup, I can chime in on it.  The bag to dslr adapter uses a metal sandwich on either side of the hole cut in the leather... so yeah, I don't see why it couldn't be fashioned to match any given mount.  Having said that, the widest lens I can focus on dslr is the 70mm, and that one is so close to the camera body that you get very little movement.  The setup is really only practical with a 90mm and longer and if you get into a MF body I wouldn't even want to hazard a guess at how long of a lens you'd have to move up to.

Sorry, not too likely. If shutter accuracy is critical, stick with the view camera bits and go electronic.

CB

[phero66]

Thanks Chris, that is what I was looking for.  Yeah I don't think at this point I will try the 645 body on it.  Looks like its electronic shutters for me.

[Rod.Klukas]

One other alternative you might find used.  Prontor made a cable release that had a timer build in.  It could repeat a time out to 32 seconds.  Was made in the 80's.  I sold several.  Maybe someone has a used one hiding somewhere.

Rod

[phero66]

Thank you Rod, I had heard of something available but didn't know the name.  Likely though, an electronic shutter is inevitable if I stay with continuous light sources, which is what is pushing me past the 1sec. barrier.  Are copal shutters even as accurate in exposure repeatability as an electronic one?  For example, if I were to shoot a color chart and track the RGB values across a series of exposures would the copal cause a variation?  If I switch over to strobe it would not matter much if it varied a little bit, the variation would then rest on the strobes performance, and copal would be fine (not using multi-shot).

[Rod.Klukas]

The electronic should be more consistent for continous lighting.  The copal are quite good if you exercise your shutter when you change speeds a couple of times.  But a longer than 1 second...

So you are correct, electronic should be best for continuous lighting and long exposures, while copal may be just as good and lower cost, if strobe is used.

Rod