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Alexa dovetailadapter


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#1 Matthias Biber

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Posted 15 November 2010 - 07:51 AM

Hi all,

The Alex camera body unfortunately does not have a flat bottom to mount the steadicam dovetailplat to.

So I made this adapter plate.

Attached File  Alexa Adapter.JPG   77.29KB   625 downloads

First it gives the camera a flat and stable surface.
Second it has the standard Arri spacing of the mounting holes. So all dovetailplates that used to fit Arri cameras will fit this adaptor (Alexa has different spacing)
Third it will extend the fore aft range of the dovetailplate by roughly 1.5”, as it can be mounted in both directions.
It also shortens the lens to gimbal distance by roughly 1” compared to arris quickrelease plate or bridgeplate.
The screws are captive and will always stay with the adapter.
Final product will be black anodized.

Alexa comes in two configurations from the rental house. First uses sony style quick release plate. The Arri Quickrelease plate is rock solid but weights 2 lbs. You can save this weight with my adapter.
Second configuration is with the new bridgeplate BP12. This will fit right in the uneven surface of the camera body. Don´t know weight of that. When you take of the bridgplate, there is no more surface to mount the dovetail to.
Arri offers an adapter for their older bridgplates with flat surface, but this will offset the nice symmetrically constructed camera to the right side.


If someone is interested in my adapter please PM me or send email to steadicamera at gmx.de and i could have a run made.
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#2 Alfeo Dixon SOC

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Posted 15 November 2010 - 02:32 PM

Arri offers an adapter for their older bridgplates with flat surface, but this will offset the nice symmetrically constructed camera to the right side.


So its not too different from the BPA-1 (http://www.arridigit...ual_SUP_2-0.pdf section 8.7). Have you found that most houses don't carry this part? Is this the one you refer to with the offset or is it not a good fit to your dovetail mounting plates?
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#3 Lawrence Karman

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Posted 15 November 2010 - 07:56 PM

How much do you think it would cost?

I'm a little confused. Charles said you could attach Steadi plates to the bottom without any type of intermediate plate. Not true?
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#4 Matthias Biber

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Posted 16 November 2010 - 07:09 PM

Alfeo,

yes it does the same as BPA-1 but without offset to the side and with more fore aft adjustability. Rental houses only need this when they use their old bridgeplates. With the new BP 12 bridgeplate, that is made for alexa, you don´t need the BPA-1 adapter.
I just don´t want to rely on the rental house to supply the adaper. Especially on these last minute calls. I want to be able to mount the camera to my dovetail, always. So I could have baught a BPA-1 from arri, or make my own, that fits a little bit more our needs.


Lawrence,

the bottom of alexa is not flat. You will need a intermediate plate. Maybe Charles´ cameras had the BPA1 already mounted.
My only concern is not to get this adapter with the camerapackage, as it is not needed with arri´s new bridgplate. Alfeo´s link to the manual is very good and shades some light to this. Look at section 8.6 as well. That is the new bridgplate.

My adapter plate would cost 70€. Depends on request if and when I´ll have them made. I´ll post in for sale section when available.
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#5 Lawrence Karman

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Posted 16 November 2010 - 11:42 PM

Count me in for one if and when you make them. How much does it weigh? Aluminum I hope?
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#6 Jess Haas SOC

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Posted 17 November 2010 - 10:41 AM

I am interested in getting one as well.
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#7 Alec Jarnagin SOC

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Posted 17 November 2010 - 01:12 PM

Sounds good to me. Reasonable price and the less parts we need to "special order"' the better. Count me in. Thanks.
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#8 Ramon Engle

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Posted 17 November 2010 - 02:26 PM

Me too.



Ramon
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#9 Alfeo Dixon SOC

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Posted 17 November 2010 - 04:00 PM

Sounds great, count me in also.

Hey Ramon, what are you using to mount on TW? Hows the CG on that camera? I would think it's pretty centered on the L to R, so that of set would require some counter measures to of mounting all your junk on the dumb side... is this close?

-Alfeo "seen one at NAB" Dixon
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#10 thomas-english

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Posted 18 November 2010 - 03:38 AM

Yeah, the non-offset nature of your offering sells it to me. I am surprised by the lack of fore-aft flexibility using my XCS plates. I've been lucky so far but you never know whats going to get thrown on next.

Count me in.
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#11 Scott Jason Gill

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Posted 18 November 2010 - 12:26 PM

Add me to the list
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#12 brooksrobinson

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Posted 18 November 2010 - 12:44 PM

I'd like one too!

Brooks Robinson
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#13 Louis Puli SOC

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Posted 18 November 2010 - 04:29 PM

Hi
Please add me to the list
Thanks
Louis Puli
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#14 Matthias Biber

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Posted 20 November 2010 - 05:50 AM

Nice to see, there is some interest in my product.
I´ll keep posting when it is ready to ship.

Material is aluminium, weight is roughly 100 gramms.
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#15 Richard W. Davis

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Posted 20 November 2010 - 09:51 AM

Nice to see, there is some interest in my product.
I´ll keep posting when it is ready to ship.

Material is aluminium, weight is roughly 100 gramms.



add me to the list.

Rich Davis
LA
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