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Trying out an old Minolta lens to take photos of my 99.1 ...

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This is a photo essay I posted on another forum today which you might find interesting:

Decided to try out an old Minolta 100mm f4 bellows lens today on my Panasonic G1 micro four thirds format camera. The subject is a Dornblüth Model 99.1 wristwatch which has a handmade and hand-decorated movement. For anyone interested in watches the base caliber is Unitas 6497 but there is not much left of the original Unitas after it has been modified. The advantage of this camera, or any micro four thirds camera, is that virtually any lens is adaptable for use in manual focus mode. I made the mistake of not setting the exposure correctly so required some post processing. I hope the colours are reasonable - my colour blindness does not make post processing easy if I get the exposure wrong.

The lens and the Minolta bellows can be bought fairly cheaply as can several other bellows lenses in the 100mm range. It's only a 3 element construction but years ago Minolta made all their own glass so maybe it has some special brew glass mixture . Leica also made an excellent lens with just 3 elements so the old adage that decent lenses must have at least 4 elements does not always apply. And because a bellows lens does not have to be a retrofocus design, it can be of much simpler construction. I used my usual kitchen mini studio set-up ie the top of the gas stove pulled out to be opposite the window - with polystyrene reflectors above and to the side. Note the focusing rack under the bellows is set up to give X and Y movements. The focusing rack is made by Elicar and is well over 20 years old and very 'dinged' but still functions well for magnifications up to about 4x - but for anything at greater magnification it is inadequate as the rack and pinion pitch is too coarse. The Manfrotto focus slide is much better as one turn of its focus screw moves the slide just 1mm.






This is the Minolta to M4/3 adaptor purchased on Ebay



The subject clamps and lockable articulated arms are part of a modular FISSO mini studio set which I've had for over 20 years - not sure if they are still available. They are very useful and time saving.


This is my Dornblüth 99.1 - chosen as a subject because it has a display back and some movement decorations ... but I did not use the clamps for the first few pix ... the need for them then became apparent


Now the bellows is extended further for increased magnification ... but I forgot to use the remote electronic release and pressing the shutter button caused wobble ... so later pix were made using the electronic release as shown in the first photo above. It is just a Chinese release bought on Ebay which is just a few ££ and very much cheaper than the Panasonic version . The watch is not quite parallel to the lens hence the top of the photo is not sharp as the bottom ... I should have used a copystand but was a Q&D setup.


And a bit closer ... I'm quite pleased with the 3 element lens performance




And this is at maximum bellows extension ... not sure exactly what the magnification is - will have to take a photo of a ruler to work it out but is probably about 3x .

Now for the display back ... this photo was very much underexposed originally but is the only picture I have of the whole movement ... need to do it again


And now the bellows is again extended to show the movement in greater detail


And the bellows is racked out further for increased magnification ... now the slightest jolt makes the viewfinder image jump all over the place .. so needed the remote release. I'm using the viewfinder to focus rather than the live view screen because the viewfinder has a better image .. and as I'm wearing distance glasses , I can adjust the diopter correction adjacent to the viewfinder for optimum viewfinder sharpness










Now the pix are posted they look a bit soft to me but that is probably the fairly flat lighting and the fact that the movement is under glass . But overall I'm happy with the 3 element lens .. and bear in mind these are JPEGS. Apologies for the colour shift just noticed in the case in the last two pix.

Any comments would be appreciated.

Cheers

dunk

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Thanks for the photos, and the details of your setup. I'm no photographer, but I'm always interested in how people take their pictures.

I wonder if more even lighting might be of some benefit? Might reduce shadows and pop some highlights better, and shorten the shutter speed (if that's one of the sources of the softness). Light box, or a ring-flash?

Tom

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Very interesting, Dunk, thanks for sharing.

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tee530 wrote:Thanks for the photos, and the details of your setup. I'm no photographer, but I'm always interested in how people take their pictures.

I wonder if more even lighting might be of some benefit? Might reduce shadows and pop some highlights better, and shorten the shutter speed (if that's one of the sources of the softness). Light box, or a ring-flash?

Tom

The lighting used is too soft and does not really suit the subject - especially as the movement is behind a display back. I would not use a ring flash because that would introduce too many unwanted reflections. I may try again using continuous tungsten light and control any reflections by directing the incident light outside the angle of acceptance of the lens.

Cheers

dunk

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