On 2/14/2017 4:06 PM, Mike Gordon via olympus wrote:
The elgant but hard way Moose writes:
<<Well, OK, there is a possible elegant manual solution, using/modifying an Oly
Bellows (and possibly leaving it so it can be restored.)
. . .
<<That would do the job of allowing focusing by moving camera body relative to
a fixed lens with excellent, smooth control. And yes, the A7 will clear everything on
the bellows. Looking on Camreasize, is appears the II and RII would also work.
Thanks for the directions and providing food for thought--not sure I have the
heart to modify my LN bellows from Bill Barber.
They are going for less than $100 on the 'Bay, some for a lot less. I bought a second a while ago mostly to get a second
focusing rail to put my Focus Stage on, so I wouldn't have to disassemble the bellows to use a focus rail.
Would like to use a very good lens in front but wonder if using a longer
registration lens like an old t-mount
The problem with T-Mount is that the adapters all correct for registration distance. Some sort of surgery would still be
required to shorten the mount adapter. For those like ChrisT with machine tools and skills, that's a doodle, but not for me.
Another arts and crafts, as opposed to machine tool, solution would be to remove the fabric bellows entirely, which only
requires a small cross-point screwdriver, and make a temporary bellows out of black rubber, or some such, which would
"bellow" out from between the standards, rather than compressing between them. With the bellows removed, the standards
collapse to 12 mm. So maybe with rubber bellows 15-18 mm, still leaving LOTS of room for focusing past infinity. The
rear mount adaptation I suggested would still be needed.
or even Mamiya 645 may be made to work and not require bellows surgery. The
Mamiya 35 isn't bad but does have more CA than I would like but would also work
on my Mirex T-S adapter. I think Kiron made a pretty good Tmount 28mm perhaps
branded as vivitar but don't clearly remember and it may be hard to find.
As with 1:1 mag, the folks writing about this stuff seem fixated very on wide angle. Is 35 mm wide enough? With the
above approach, anything down to 18 mm is easy with existing OM lenses.
The problem is then the possible thin custom adapters required--they don't
come cheap from Srb griturn if they even will fabricate them anymore. I
also wonder what would happen if one mounted a WA on a screw macro rail
http://www.reallyrightstuff.com/B150-B-Macro-focusing-rail (there are cheaper
alternatives) and moved the cam back the same amount the helicoid moved the
entrance pupil forward????? perhaps mount a laser to align i
t in front--no clue what happens to the framing and whether one could get the
images to align and clean up OK in post. May be a recipe for madness.
Yeah, that sounds crazy making. The Oly Bellows is amazingly smooth and precise - and a lot cheaper than that RRS rail.
I have a couple of other, cheap, focusing rails/devices, and they just aren't very good.
Macro landscaper or mad as a hatter, Mike
There's a difference?
Been Known to Macro Moose
--
What if the Hokey Pokey *IS* what it's all about?
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|