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Explore the world of vintage lenses through repair notes, real test shots, and detailed archive threads packed with images.

Explore the world of vintage lenses through repair notes, real test shots, and detailed archive threads packed with images.
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Kyocera 100mm f1:4 Macro for C/Y
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It has been a long time for me to search for a good macro lens on budget - two things that are often opposite. And as I am on budget for camera accessories too, why not get a macro lens with integrated ring flash ? Laughing

Actually you can find some lenses of this kind made mainly for medical usage : the Medical / Oral / Dental cameras lenses. Yashica, Nikon and probably Canon did those in various flavour - the first so called Yashica Oral-Eye was a suitcase containing an Electro GT rangefinder, a 55mm f1/4 macro lens and a battery grip (see more at www.yashica-guy.com).

My idea was to get such a kit to... get the lens. My favorite one is the Yashica Medical 100DX, a 35mm SLR Yashica body with a removable 100mm f1:4 C/Y mount lens, integrated ring flash with external battery pack and some electronic servo to control the apperture (see more at www.mir.com.my)
But they often goes for more than 100 € on eBay and are not that commonly seen. Rolling Eyes

So when I see a latest variation of the Yashica serie (Dental-Eye III) goes for cheap, I couldn't resist - why cheap ? Because the camera was sold as broken; "I don't care !" I said, just wana that nasty lens !! Twisted Evil

Yesterday the kit in its dedicated suitcase arrived, e baste con le chiacchiere, here are some pictures of the beast !











As you can see and as written in the provided documentation, "the Dental-Eye III is a one-piece 35mm single-lens reflex camera with 100mm/F4 macro lens and build-in flash". Yes, one-piece camera ! I guess it was pure marketing shade of smoke, I can't imagine this lens (optically the same as for Medical 100DX camera kit) being re-engineered) Cool

So let's go for a little surgery - what a shame for a medical camera Very Happy

- Under the camera, battery door removed you will find 6 screws, remove them all :


- Remove the under cover carrefully (there are 2 wires for the battery attached to it) and now you can see under a bunch of wires a small "T" piece of metal that connect the lens to the body with 2 screws; unscrew the lens part :


- Now on the right side of the lens mount, you will find 2 small round rubber cache : remove the top one's - it hides the lens blocker lever actually found on other Yashica cameras.


- Insert a thin metal tool (small screwdriver) into this hole, and while pushing it, turn the lens counter-clockwise. Here we are !


Now and as expected (you said I was lucky ? It's pure genoious brain, man !! Laughing), I have a C/Y mount 100mm f/4 macro lens with built-in ring flash ! This was the easy part, because I now need to wire myself the built-in flashes (there are 3 !) and electronic apperture to be abble to use fuly this "little" gem Embarassed

But no latter than now, let's put it in front on my EOS 350D body with hands (I still dont have any C/Y to EOS adapter) and take some shots of my beloved Helios-44-2 lens !

1:15 macro ratio, full frame resized & unsharpened :


100% crop with some sharpening :


1:1 macro ratio, full frame resized & unsharpened :


100% crop with some sharpening :


I also have the 2:1 lens add-on that screw in front of the camera but it's not really usable with a strong lens to camera link - mine was virtually none here, so some camera shakes are clearly visible.

Cheers !

P.S: oh, did I write "Kyocera" as subject ? Well actually, Yashica is a brand owned bu Kyocera, and this maker has some strong experience in optical products, appart from many other things - the lens is 100% kyocera made.


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Unbelievable


Good for you

Amazing



patrickh


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I love it! The step by step dismantling is great fun.

Very environmental of you as well as crafty Smile A perfect example of re-use before recycle. What will you do with the body? To bad it is inop, it looks just like a Contax ST which was a great Kyocera built camera of the same era. BTW I just received a chipped C/Y to eos adapter from roxsen. I have read in this forum that some people had trouble with them. My adapter arrived in 4 days from HK to Seattle and works perfectly. Maybe this means they have improved recently.


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Thanks for that - great photo story Smile

That was a great price.


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Excellent photographic reportage, Flor! And very instructional.
And I must say, impressively huge piece of lens!! My Makro-Planar disappears in the comparison.
The ring flash sounds like the perfect tool to use for macros, I hope that you can make it work.
Congratulations on a great piece of hardware!
BTW love the camera also. Is the camera fully functional after the surgery?

Orio
P.S. your beloved Helios is a little filthy I would say Wink


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Quote:
It's pure genoious brain, man !!

You are a crazy genius brain Florent, congrats Very Happy


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Thanks for all you comments !

The camera was sold as broken, vendor says "flash fire, shutter works but once a film is loaded into the camera, it is not winded and the shutter won't works no more".

This surgery is fully reversible and the camera should work without the lens, but as I have no battery yet I can't try to repair it.

About this camera, it's a fully automatic one, you cannot choose speed nor apperture... controls available are : +1/-1 EV in 1/3 step. Flash/No flash/2 lower lights of flash only; date back; ISO from DX film cardrige; ON/OFF and that's all. I guess you will understand that it will not be too much loose if I can't make it works again Rolling Eyes


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Orio wrote:
P.S. your beloved Helios is a little filthy I would say Wink


Oh yes, and I must take macro shots of the front lens to show you how much scratch there are... anyway, all pics appart the macro ones were done with this Helios at f/22 Very Happy


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Flor27 wrote:
...all pics appart the macro ones were done with this Helios at f/22 Very Happy
...but the Helios goes from f:2 to f:16 only Wink (as you can see in you picture) Smile


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Ooops sorry, my coffee haven't yet makes me up fully... Yes you are right, f/16 shots.


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I now remenber where I got hint about the possibility to remove the lens :

Click here to see on Ebay


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http://cgi.ebay.com/Yashica-ML-Macro-55mm-f-4-Lens-For-Yashica-or-Contax_W0QQitemZ270190400098QQihZ017QQcategoryZ3340QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Copy and paste link nice yashica 55 f4 macro for under $100 BIN.


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Wow - excellent piece of kit and nicely done.


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Update : in order to mount this lens on EOS body with a C/Y adapter, you will need to slim the rear's end of the black conical part as it's too protruding. It will not affect in any way the lens functionnalities and it will still possible to mount it on the Dental camera.


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Simply amazing Flor. Good for you! and my hat is off.


patrickh


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Excellent !

Shocked


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It's like a game: sometime, you see something that you think having already seen in the past but can't remember when and where... and then you are lucky - or not.


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Where is the aperture ring... seems like always open condition (once dismantled)...


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some news ?


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"No user serviceable parts"

"Oh rly?" screw prise wrench pop

So this lens is somewhat similar to the medical nikkor 120mm f/4?


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Hi all,

Aperture is electronicaly activated by the body, as on Canon EOS lenses, so it stays full open otherwise. Also for the built-in flashes.

This job will not be started soon, I have too many other things to do prior this one, but here is the way I will try to hack it on spare time :

- connect the lens to the camera
- connect some oscilloscope on the wires
- take a picture
- write down the timeline of those two wire
- repeat for the other wires you didn't analyse

- try with other film sensitivity to see what's change
- try with other flash setting

- try to guess what each wire do, and how.

- simulate the camera body with home made electronics to have a fully working lens

What a job !


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Florent wrote:
try to guess what each wire do, and how

Wow Florent! You are a hacker Very Happy


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poilu wrote:
Florent wrote:
try to guess what each wire do, and how

Wow Florent! You are a hacker Very Happy

I have studying electronic prior to working in IT, but it will not garantee any succes Wink


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Flor27 wrote:
Update : in order to mount this lens on EOS body with a C/Y adapter, you will need to slim the rear's end of the black conical part as it's too protruding. It will not affect in any way the lens functionnalities and it will still possible to mount it on the Dental camera.


But how do you control the aperture of this lens.. I am not seeing any aperture ring. I think, in latter models, the aperture control was from electronic control from camera...


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Ballu wrote:
But how do you control the aperture of this lens.. I am not seeing any aperture ring. I think, in latter models, the aperture control was from electronic control from camera...

That what I have said, yes. In order to control the aperture, you need to reverse engineering the functionality of each wire that connect the lens to the body.