Mamiya RB to large format adapter

k_jupiter said:

Acouple of things... Someone posted a long time ago how to take the front piece off a trashed rb body and mount it on a lens board to use with rb lens. The trick is toget the cocking of the shutter correct. I have the front piece, just never got aroundtoit so it's just another project.

I have no idea of coverage. Some claims seem a bit outrageous.

The rb backs will fit a Grafex back. I have used it on my 2x3 Speed. But ya know... I think the film plane offset is just not quite correct. The negatives are a bit..soft.

YMMV.

tim in san jose

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Tim (and anybody else interested in this),
I've posted a pdf of the RB lensboard page here: http://cid-5f9b69ac980337e6.office.live.com/self.aspx/.Public/Rb lensboard info page.pdf

Not perfectly formatted, but until I get my website back up (after a 3 year ordeal to successfully get my domain name back...), I wanted that info to be available.

erie

Marc B. said:

xkaes,
Yes I have seen a lens board adapter for LF, and from different vendors. Don't remember who had it; ie,
an eBay seller from China, Calumet, etc...? It was advertised as being for RB [and] RZ lenses.
As stated by others, unsure how you were supposed to cock and fire the shutter, and without electrical control for the RZ lenses,
how you would obtain different speeds, other than the [dead battery] default speed of 1/400th.
I think this adapter was intended more for RB lenses, and those using a digital back on their LF cameras.
Price was high, in the $450-$550/USD range.

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Wow!!! No wonder I'm still broke, I've been giving this info away for years for free!!!

epatsellis said:

Wow!!! No wonder I'm still broke, I've been giving this info away for years for free!!!

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Haha, yup.

epatsellis said:

Tim (and anybody else interested in this),
I've posted a pdf of the RB lensboard page here: http://cid-5f9b69ac980337e6.office.live.com/self.aspx/.Public/Rb lensboard info page.pdf

erie

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Thanks Erie. Three years?! Oh dear, that means it's been at least that long since I've been meaning to do this.

David Grenet said:

Thanks Erie. Three years?! Oh dear, that means it's been at least that long since I've been meaning to do this.

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Yes,
And if you have a domain name that is your personal name, and your name isn't very common, don't ever let it expire unless you don't care. After having several squatters think I'm paying $4k+ for the domain name, all off shore btw..., I finally got "lucky" and a squatter based in the US eventually owned it. It took baiting them into offering it for sale to me, then threatening an ACPA federal lawsuit from a lawyer (there's only one person named Erie Patsellis in the world, they purchased it solely for resale, have never used it legitimately (showing bad intent), etc...) before they realized that it would be better to simply surrender it to me, finally.

Now to figure out hosting not based in my office, as running a fat pipe, 3 single phase UPS's and a server 24x7x365 isn't practical anymore from a financial standpoint.

The RB lenses cover a bit more than 6x7 since the actual "throat" is 7x7, that's still short of the 12x12cm that 4x5 requires. Some lenses may cover stopped all the way down, but the RB lenses are not really intended for such minimum aperture work except in a pinch (I would check for loss of sharpness from diffraction). that said you'd also need to either use a lensboard that will cock the lenses whilst mounted or remove the lens from the lensboard every blasted time and recock the lens. Additionally the lenses are made to stay open while composing and then close and fire when the shutter release is pressed. Note that the RB uses a Copal type shutter (I think the earlier ones are different from later lenses but not that different) so you could remount the elements in a standard Copal but this sounds like too much work to make me happy.

Yes! A several months ago, an Asian source was selling a fair number of them. Who knows, they may come around again.

Though it belongs to a friend, I have one in my possession. It includes a lever to cock the shutter. Seems to work great. It fits some unknown camera. But one can easily adapt it to a large enough board, like a Sinar, Arca, etc.

It's true, they may or may not cover 4x5. But, if one attaches RB lenses to the front and uses another adapter to attach a digital camera to the back, the VC movements can be used to stitch a high resolution, digital image. The nice thing about the RB lenses, is that they're sharper than typical VC lenses.

RB lenses are also inexpensive. I've been seeing Hassleblad lens adapters recently on EBay. But, they're a LOT more expensive, and they don't have the coverage of RB lenses.