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Re: [OM] Oly 4/3 vs m4/3 lens mounts and adapters

Subject: Re: [OM] Oly 4/3 vs m4/3 lens mounts and adapters
From: Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx>
Date: Sun, 19 May 2013 07:32:25 -0400
That's a great find but we're apparently coming at our views from 
different sources.  If I read you correctly you're looking at the 
*actual product* and stating that the outside of the 49mm end is not 
threaded and the inside has ridges.  What I've been looking at is the 
handy_copy_stand.pdf.  That's a copy of the user's manual in PDF form 
that was included in the eSIF as distributed on CD.  That clearly shows 
the 55/49mm adapter to have threads on the outside of the 49mm end as 
would a 49mm filter.  The interior ridges are not illustrated.

Chuck Norcutt


On 5/18/2013 9:29 PM, Mark Dapoz wrote:
>
> I had to dig out my sample of the copy stand to figure out exactly
> what is going on.   The 43 -> 49 and 22.5,43.5 -> 49 adapters do
> indeed have threads only on the smaller side, the 49mm copy stand
> side is completely smooth.  The 55 -> 49 adapter on the other hand
> appears to have threads on both sides of the adapter, but on closer
> inspection the 49mm side "threads" aren't really threads.  The inside
> of the adapter has ridges which makes it appear to have threads but
> they aren't.  I suppose Olympus did this to cut down on any light
> reflection since the adapter is going into a larger lens opening.  So
> the illustration in the SIF is correct, only the assumption that
> they're threads is incorrect.
>
> -mark
>
> On 13-May-18, at 7:45 PM, Chuck Norcutt
> <chucknorcutt@xxxxxxxxxxxxxxxx> wrote:
>
>> I don't know what you refer to as the "SIF" other than source
>> documents for the eSIF that I don't have.  But the eSIF does
>> reference the user's manual for the Handy Copy Stand which does
>> show the 3 adapters available for it.  One of those is the 49/55
>> and, as you stated, the drawing shows the 49mm side as threaded
>> whereas the other two adapters are not threaded on both sides.  I
>> agree.  It must be an error.
>>
>> Chuck Norcutt
>>
>> On 5/18/2013 4:00 PM, piers@xxxxxxxx wrote:
>>> The 55-49 adapter appears in the SIF (not eSIF, where it is said
>>> to be optional) as part of the Handy Copy Stand set, for just the
>>> same application, and the illustration is consistent with your
>>> description, except it has a thread on the 49mm end. I think
>>> that's an error, as the smaller adaptors don't have a thread.
>>>
>>> Piers
>>>
>>> On 18/05/2013, Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx>
>>> wrote:
>>>> The next question is whether the 49/55 adapter was originally
>>>> supplied with the bellows.  Does anyone actually have one of
>>>> these and does it look as I described that I think it must
>>>> look?  Searching the eSIF (briefly) did not reveal such a part
>>>> to me.
>>>>
>>>> I've got to think about how to replicate a part like that for
>>>> reversing my 90/2.5 Viv S1 macro which a 58mm filter.  If
>>>> there's a 49 to 55mm filter adapter that would work.  You'd
>>>> need the ring from the 49mm filter to make a 51mm diameter
>>>> attachment point for the bellows.
>>>>
>>>> Chuck Norcutt
>>>>
>>>>
>>>> On 5/18/2013 3:03 AM, piers@xxxxxxxx wrote:
>>>>> Splendid stuff, Chuck, it all does now make sense in a way
>>>>> that eSIF and SIF (which I also reviewed) don't even
>>>>> approach. It was late, I didn't follow my own advice to just
>>>>> try it!
>>>>>
>>>>> Piers
>>>>>
>>>>> On 18/05/2013, Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx>
>>>>> wrote:
>>>>>> You're inferring stuff rather than actually measuring the
>>>>>> bellows.  I have done my due diligence and discovered that
>>>>>> the eSIF is perfectly correct.  The reason that a Series VI
>>>>>> is used is that hole is supposed to take a filter... a
>>>>>> Series VI size filter... which Wiki tells me thus: Series
>>>>>> number   Filter size     Adapter ring VI         41.3 mm         44 mm My
>>>>>> handy dandy millimeter rule tells me that the thread on the
>>>>>> back of the lens board is (whaddya know) 44mm.  I
>>>>>> discovered that very quickly since no 49mm filter would fit
>>>>>> there.  That threaded hole is specifically for a filter and
>>>>>> not for reversing lenses.
>>>>>>
>>>>>> Once again, the bellows manual tells you nothing about that
>>>>>> filter provision.  Your confusion about reversing lenses I
>>>>>> think comes about from assuming that it's done the way you
>>>>>> would on a camera body by attaching two lenses together
>>>>>> joined by a male threaded ring with threads on each side to
>>>>>> match the lenses to be joined.  You've assumed that the
>>>>>> 49/55 adapter is one of those rings... but it is not.  It
>>>>>> has a totally different function and isn't really 49mm on
>>>>>> one end.
>>>>>>
>>>>>> Once you turn the front lens board around you don't need
>>>>>> any sort of threaded adapter since the OM lens mount on the
>>>>>> lens board is now facing the camera.  Just install the lens
>>>>>> on the normal lens mount and it, like the lens board, is
>>>>>> now reversed.  Where the 49/55 adapter comes in has to do
>>>>>> with attaching the bellows itself to the lens.  The
>>>>>> attaching ring normally attaches to a ring on the back of
>>>>>> the lens board that is about 51mm diameter... or the
>>>>>> outside diameter of a lens having a 49mm filter. When you
>>>>>> reverse a lens having a 49mm filter the bellows attaching
>>>>>> ring fits over the lens in the same way as it does the ring
>>>>>> on the back of the lens board.  But when you use a lens
>>>>>> with 55mm filter the lens is too large.  It needs a
>>>>>> step-down ring.  Now, since I have never seen one of these
>>>>>> step-down rings I can only conclude that it has a 55mm
>>>>>> thread on one end and a 51mm unthreaded ring on the other
>>>>>> such that it presents the same diameter to the bellows
>>>>>> attaching ring as the ring on the back side of the lens
>>>>>> board.
>>>>>>
>>>>>> Or something like that.  If you know something else correct
>>>>>> me.
>>>>>>
>>>>>> Chuck Norcutt
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> On 5/17/2013 6:23 PM, Piers Hemy wrote:
>>>>>>> Without looking at the Bellows manual I would opine that
>>>>>>> it would be surprising to find that Olympus did not use
>>>>>>> the 49/55mm thread there, as it is intended for reversing
>>>>>>> OM lenses on the (reversed) front standard. Why would
>>>>>>> they use a thread incompatible with all and any of their
>>>>>>> own lenses? And in place of reading a secondary source
>>>>>>> (useful as the eSIF is), why not try it?
>>>>>>>
>>>>>>> So I did look at the 12/81 edition of the Auto Bellows
>>>>>>> manual, and guess what?
>>>>>>>
>>>>>>> I was wrong.
>>>>>>>
>>>>>>> And so is the eSIF, only more wronger (!)
>>>>>>>
>>>>>>> It's a 49mm thread, as "The adapter ring 55-49mm is
>>>>>>> needed to reverse the Macro 55mm F1.2 on the bellows" (p
>>>>>>> 14). Granted, they described the 55/1.2 as a Macro lens,
>>>>>>> which it isn't, but it does have a 55mm filter thread,
>>>>>>> from which I conclude the bellows has only a 49mm
>>>>>>> thread.
>>>>>>>
>>>>>>> Piers
>>>>>>>
>>>>>>> -----Original Message----- From: Chuck Norcutt
>>>>>>> [mailto:chucknorcutt@xxxxxxxxxxxxxxxx] Sent: 17 May 2013
>>>>>>> 22:26 To: Olympus Camera Discussion Subject: Re: [OM] Oly
>>>>>>> 4/3 vs m4/3 lens mounts and adapters
>>>>>>>
>>>>>>> I tried the focusing stage since Wayne said he'd gotten
>>>>>>> such an arrangement to work with his Pen and, if it
>>>>>>> worked, would require nothing more than what I already
>>>>>>> have.
>>>>>>>
>>>>>>> I didn't come up with your solution since I've never
>>>>>>> completely read the bellows description in the eSIF which
>>>>>>> is, I think, the only place that tells you that the back
>>>>>>> of the lens board is threaded.  But it looks like you
>>>>>>> need to re-read it yourself :-) since the thread is for a
>>>>>>> Series VI filter and is not a 49/55 filter thread.
>>>>>>> Nevertheless, your solution should work given the right
>>>>>>> bits and pieces.
>>>>>>>
>>>>>>> But re-reading the eSIF to understand what you had
>>>>>>> written caused me to think about reversing the lens which
>>>>>>> might provide a bit more room to maneuver since it moves
>>>>>>> the thick base of the lens board to the back side. Maybe.
>>>>>>> Thanks for the memory jog.
>>>>>>>
>>>>>>> Chuck Norcutt
>>>>>>>
>>>>>>>
>>>>>>> On 5/17/2013 5:35 AM, Piers Hemy wrote:
>>>>>>>> I may have missed something obvious, but why are you
>>>>>>>> using the focusing stage? Remove the rear standard
>>>>>>>> (camera mounting board) and bellows from the bellows
>>>>>>>> rail, and use the 49/55mm filter threads on the back of
>>>>>>>> the front standard (lens board) to mount the OM-D.
>>>>>>>> You'll need a 55mm m4/3 reverse adaptor such as
>>>>>>>> 271191801433 on the auction site, and a female-female
>>>>>>>> filter adaptor such as this:
>>>>>>>> http://www.camera-filters.com/index.php?main_page=product_info&cPath=4
>>>>>>>>
>>>>>>>>
31&pro
>>>>>>>> ducts_id=7214
>>>>>>>>
>>>>>>>> You may also need a blank filter ring to get extra
>>>>>>>> separation, but I'm sure you'll work that out!
>>>>>>>>
>>>>>>>> Piers
>>>>>>>>
>>>>>>>> -----Original Message----- From: Chuck Norcutt
>>>>>>>> [mailto:chucknorcutt@xxxxxxxxxxxxxxxx] Sent: 16 May
>>>>>>>> 2013 18:04 To: Olympus Camera Discussion Subject: Re:
>>>>>>>> [OM] Oly 4/3 vs m4/3 lens mounts and adapters
>>>>>>>>
>>>>>>>> I'm removing the grain of salt.  I mounted the E-M5 on
>>>>>>>> the focusing stage, installed the OM adapter and some
>>>>>>>> OM extension tubes and then put the OM body mount from
>>>>>>>> the bellows onto the end of the tubes. Running the body
>>>>>>>> mount into the bellows connector resulted in the E-M5
>>>>>>>> setting in a non-level position on the focusing stage.
>>>>>>>> I think my guess of 3mm (maybe 2mm) vertical
>>>>>>>> misalignment may be about right but it's not the height
>>>>>>>> of the body or lens center lines.
>>>>>>>>
>>>>>>>> I had assumed that the OM body was lower and would
>>>>>>>> align properly. Nope, the two camera's lens centers
>>>>>>>> appear to be at the same height so an OM-1 on the
>>>>>>>> focusing stage doesn't align either.  The problem of
>>>>>>>> vertical misalignment is caused by the height of the
>>>>>>>> focusing stage.
>>>>>>>>
>>>>>>>> Chuck Norcutt
>>>>>>>>
>>>>>>>>
>>>>>>>> On 5/15/2013 11:15 AM, Chuck Norcutt wrote:
>>>>>>>>> A quick and very rough measurement looks like the
>>>>>>>>> vertical centerline of the E-M5 is about 3mm higher
>>>>>>>>> than an OM body.  But take that with a grain of salt.
>>>>>>>>> Also, like the E-P1 the tripod thread is off center
>>>>>>>>> from the lens center by about 9mm.  That, however,
>>>>>>>>> could likely be solved by drilling and tapping a new
>>>>>>>>> hole in the focusing stage. I'll take a better
>>>>>>>>> measurement later since this has some promise.
>>>>>>>>>
>>>>>>>>> Chuck Norcutt
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On 5/15/2013 8:17 AM, Wayne Harridge wrote:
>>>>>>>>>> G'day Chuck,
>>>>>>>>>>
>>>>>>>>>> Something like this should work:
>>>>>>>>>>
>>>>>>>>>> http://www.structuregraphs.com/RandomStuff/15-May-20
>>
>>>>>>>>>>
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