MInolta bellows III: conversion to MFT

Discussion in 'Adapted Lenses' started by Austrokiwi, Apr 21, 2016.

  1. Austrokiwi

    Austrokiwi Mu-43 Regular

    48
    Mar 19, 2016
    I suspect some people reading this will have clicked on this thread just to see why any one would bother converting a bellows to MFT. There are plenty of Adapters that will allow us to couple a MFT camera to a bellows supposedly without in need to convert those bellows to the MFT mount.
    To begin with some background. Most of my photography interest developed from my main hobby coin collecting. In wanting to produce good pictures of my coins and later high resolution pictures for Journal articles I developed a real interest in Macro photography. My interest coincided with the development of mirror-less cameras and I went the full frame route with Sony. However over the last year I started to realize a bigger sensor may not actually be the best approach. With a Full frame sensor I was being forced to focus stack ( using the cognisys stackshot system). The issue was that to fill the full frame sensor with the image of the coin I had to use high magnification resulting in shallow depth of field. With an MFT sensor I knew that I would use much lower magnifications with a corresponding increase in the DOF.

    DSC03406.JPG


    Before I purchased my MFT camera I already had a macro rig set up( vibration resistant) and two Minolta Bellows III. This particular model is very well made and it has the advantage of being tilt-shift. Also both the front and rear bellows standards move so you can mount the bellows and not have the bellows rail extending in front of the lens( which can be very annoying when you need to focusing close to the subject).

    As soon as I started mounting the MFT camera to on of these bellows I ran into a problem. The adapter needed Minolta MD-MFT added far too much extension. With the adapter there was 85mm between the lens and the camera sensor As can be seen here:

    DSC03419.JPG

    This meant I was getting shots like this at zero Bellows extension:


    mil.
    I had recently discovered that the Minolta MD/MC camera mount on the bellows could be easily removed so I contacted RAF Camera in Belarus and asked if he could make a replacement mount for the Bellows. As a result today I received the replacement mount. Fitting it was reasonably simple. I first un-clipped the bellows from the front standard.

    DSC03407.JPG


    I then removed the bellows from the rear standard, this involved unscrewing four tiny screws (inside the bellows) once the bellows was off the rear mount I could access the retaining ring that holds the MD/MC mount in place.

    DSC03409.JPG
    (You can see the four small screw holes that are used to hold the bellows in place)
    The new mount made by RAF camera is machined so that it uses that same retaining ring. It was just a simple matter of swapping the original mount with the RAF made MFT mount and then I reassembled the bellows( total time of disassembly and reassembly was just over 6 minutes)


    This is what the finished conversion looks like

    DSC03411.JPG


    DSC03416.JPG




    And this is what the bellows can produce with the reduced gap between the sensor and lens( now 65mm)

    P4210002.
    Here is the modified bellows mounted on my rig( note the lens is a Schneider Kreuznach APO 45/4 HM

    DSC03418.JPG

    I can still do high magnification work with the modified bellows and the conversion is reversible. This conversion can also be performed on the Minolta Bellows IV( which is non-tilt shift)
     

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    Last edited: Apr 21, 2016
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  2. eteless

    eteless Mu-43 All-Pro

    Jun 20, 2014
    Looks like a Kaiser 4x5 enlarger in it's copy stand guise? The older enlargers are great for it as the cast iron damps vibrations...

    Good result :)
     
  3. MAubrey

    MAubrey Photographer

    Jul 9, 2012
    Bellingham, WA
    Mike Aubrey
    The OM-10II does focus stacking in camera, too, right?
     
  4. Austrokiwi

    Austrokiwi Mu-43 Regular

    48
    Mar 19, 2016
    Good guess but slightly off target. The macro stand was originally a kaiser enlarger stand. now the only part that remains of that enlarger stand is the mount that connects the column to the base board. Every thing else was replaced, some of the replacements were kaiser parts purchased new. The baseboard is a 600mm X 600mm X 30 mm slab of granite ( weighs 29kg). The column is now a Kaiser 4476 which has weight compensation, and the camera arm mount can be locked into place on the column. The camera arm is a Kaiser RA 101 which is is only 45mm in length against the standard 100mm. I then use a series of Swiss arca clamps and rails to change how the camera is mounted. This includes two small panorama clamps that are used to adjust level( Chinese made arca rails are not that accurately machined). The macro stand sits on Sorbothane feet ( to dampen vibration). Underneath a bench style table sits on two 15 kg concrete slabs. What you can't see in the picture is the stack-shot focusing rail( hidden behind the camera in the pictures)

    Correct but the Cameras stacking system is too much of a "black box" for my purposes. With the stack shot I can adjust how many microns the focus moves between each shot. Also, although the Oly 60mm macro is a nice lens it just doesn't match the performance of other lenses( which can't use the cameras stacking) I have. In fact I would rate the Oly ED 50mm F2 Macro lens ( which can't use the cameras focusing stacking feature) as a much better performer than the 60mm. It would be really nice if Olympus actually reissued the ED 50mm in MFT format, improving that lenses focusing system in the process.
     
    Last edited: Apr 23, 2016
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  5. eteless

    eteless Mu-43 All-Pro

    Jun 20, 2014
    Sounds like a really nice setup, close but no dice with the guessing game. I find using well thought out and setup equipment actually makes the job more enjoyable.

    I also agree about the performance of native lenses compared to the potential of adapted lenses, I'm holding onto a set of Rodenstock APOs just in case (40mm, 50mm, 75mm, 135mm. their ebay value doesn't match their real world potential imo).
     
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  6. Austrokiwi

    Austrokiwi Mu-43 Regular

    48
    Mar 19, 2016
    In regards to the guessing game I assume you mean Oly's focusing stacking feature. I agree I don't like guessing. I have my own DOF calculator that consists of a Microscope calibration slide mounted at 45 degrees. When setting up a shot I image the calibration slide, measure how much is in focus and then using pythagoras calculate how much vertical focus movement is required in the stack, which is then programed into the stack shot controller. I am envious of the collection of APO Rodenstock optics, brilliant lenses for macro work.

    Edit: ON the guessing game/"black box", I was really disappointed with Olympus, I did approach them and ask for the information that would take the guessing game out of using their focus stacking feature but they won't release the info necessary as they regard it as commercially sensitive. As a result, for me the Olympus focus stacking feature is a waste of time. I have started making a table relating depth of field in Microns to magnification and F stop... but I doubt i will ever finish it.
     
    Last edited: Apr 23, 2016
  7. Bytesmiths

    Bytesmiths Mu-43 Veteran

    I've looked at photos of what are claimed to be "Minolta Bellows III" on evilBay, and they do not look like yours. From the evilBay photos, I do not understand how they can achieve tilt and shift. The ones on evilBay have bright metal focus knobs, and nothing resembling the bevel-and-groove used for shift on the front standard of your bellows.

    Any thoughts on this discrepancy?

    I really want a tilt-shift bellows for model photography, and was excited to see yours. But it appears to be made of unobtainium!

    EDIT: Now I realize that the magic one is the "Minolta Auto Bellows III." And sellers know it — $395!

    Guess I'll just take a hack-saw to my Olympus auto-bellows...
     
    Last edited: Mar 26, 2017
  8. Austrokiwi

    Austrokiwi Mu-43 Regular

    48
    Mar 19, 2016
    Reasonably priced examples are indeed made of unobtanium. The seller you refer to rarely end up with a sale. I have two of the Autobellows III However it took me 2-3 years to get them at an affordable price. One cost me about US$100.00. The other was a fluke, I had purchased a broken non- Tilt shift version for parts, and one day I saw on e-bay a second cheap parts Tilt-shift bellows that was only missing the rail and the rail from the fiust parts example was a perfect match!!
     
  9. Bytesmiths

    Bytesmiths Mu-43 Veteran

    Thanks. I'll keep my eyes open.
     
  10. Bytesmiths

    Bytesmiths Mu-43 Veteran

    Unfortunately, it appears that focus stacking only works with Olympus 4/3rds lenses.

    It would have been totally cool if they were doing it using their exquisite sensor-shift technology, but it appears to require communication with the lens.
     
  11. Bytesmiths

    Bytesmiths Mu-43 Veteran

    It arrived today, and I just installed it.

    Something to pass on to your Russian friends: they need to make the threaded distance a bit shorter, so the adapter will "float" in the mount when tightened down, and they need to add two tiny stop-screws: 1) to restrict the mount to 90° rotation in the bellows, allowing quick tactile switch to portrait orientation, and 2) to keep the mount from turning past the release point on the body.

    Don't get me wrong; I'm glad this exists. But for $43†, I had hoped it was a bit more true to the original.

    I will put some LockTite on the threads, so that I don't have to tighten it all the way down in the bellows, so it can "float" like the Minolta mount did. This will allow the bellows rear standard thumb screw to control rotation, allowing the camera to be positioned anywhere from landscape to portrait… and beyond. I just might just tap a little stop screw in there… it appears to need to be 90° CCW from the lens "top" marker… get out the Dremel… :)

    While I'm at it, I'll add the set-screw that keeps the lens mount from turning past the release point on the body.

    I'm also in the process of replacing the front mount with an Olympus OM body mount. (I have four bellows-only Olympus macro lenses!) After puzzling with concentricity issues, I discovered that the Olympus OM extension tubes have just the right diameter to fit inside the recess left when the Minolta body mount is removed. So I butchered my 7mm Olympus OM extension tube and sanded it down to make the thickness right. Now I'm waiting on a set of jeweler's taps to arrive so I can thread mounting holes in the Olympus OM body mount.

    I'm also cobbling a lever together that will allow the stop-down button to work in reverse: the lens will normally be stopped-down, but pushing the button will open it wide. Hey, I couldn't just leave that nice button sitting there doing nothing, could I? :)

    What to call it? Minlympus? Olyolta?

    Pictures to follow, if anyone's interested. I sometimes get more pleasure out of modifying equipment than I do using it… If anyone else wants one of these, but lacks the skills, will work for camera equipment… :)

    BTW: KEH has a Minolta Auto Bellows III right now for only $99; I paid $120 on evilBay.

    You can buy the adaptor direct from the Russian manufacturer for $39, but I don't know if that includes shipping, like the $43 ebay route does.
     
    Last edited: Apr 27, 2017 at 9:23 PM
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  12. TNcasual

    TNcasual Mu-43 Hall of Famer Subscribing Member

    Dec 2, 2014
    Knoxville, TN
    Your issue with the adapter distance maybe be the reason why have difficulties with my Leica R bellows. It is difficult to frame with my E-M10.

    When I adapt it on my Fuji X-E2 I get a better field of view. It still has the adapter difference, but the sensor size helps.

    Hmmm. Maybe I can get a new mount made for the bellows.
     
  13. MAubrey

    MAubrey Photographer

    Jul 9, 2012
    Bellingham, WA
    Mike Aubrey
    Ah...that's unfortunate.