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Olympus MC-14 Teleconverter for m43rds cameras

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#1 dabateman

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Posted 11 April 2021 - 07:33

Olympus has two teleconverter options for micro four thirds. The MC-20x which is a 2.0 teleconverter and the MC-14, which is a 1.4x teleconverter which looses you a stop of light.
I only own the Mc-14 teleconverter. Panasonic also has similar teleconverters, but I don't own either of them.

The Olympus MC-14 has a front element that sticks out a lot. So its use is limited to very few m43rds lens. However you can modify the the Olympus MMF-3 adapter, by cutting off a silly plastic tab and mount the MC-14 to the MMF-3 and then mount Olympus four thirds lenses or anything to the four thirds mount. Whats great about this modification is Olympus cameras don't think its possible, so they don't report the teleconverter and this allows you to mount the Olympus EC-20x or EC-14x four thirds teleconverters on top and still get autofocus. All three will not autofocus.

I have scanned these with my spectrometer. My light source is weak into the IR range and No integrated sphere was used. Read these plots at your own risk.

The UV transmission for the Olympus MC-14 is as follows:
Attached Image: Olympus EM14x.jpg

UV cut off 358nm
50% transmission at 375nm

So the newer on is better than the older EC-14x:
Attached Image: OlympusEC14.jpg

UV cut off 366nm
50% transmission at 392nm

Olympus EC-20 four thirds teleconverter:
Attached Image: EC20.jpg

UV cut off 358nm
50% transmission at 385nm


My light source is weak in the IR, so don't jump to conclusions there.

Edited by dabateman, 11 April 2021 - 14:09.


#2 OlDoinyo

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Posted 11 April 2021 - 13:35

I always assumed teleconverters were a bad idea in UV. This post does not particularly dissuade me.

Come to think of it, I don't use them much any more even in the visible. In the days when resolution was limited by film rather than by the optical train, they made sense: blowing up the image could gain you additional detail without having to magnify grain. But a teleconverter cannot ultimately resolve any detail that the base lens does not already; it cannot create additional optical resolution and in real life will always exact some penalty in that department. So in most cases with modern high-resolution digital sensors, you are better off just using the base lens and cropping the image.

#3 dabateman

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Posted 11 April 2021 - 14:03

View PostOlDoinyo, on 11 April 2021 - 13:35, said:

So in most cases with modern high-resolution digital sensors, you are better off just using the base lens and cropping the image.

You really need to test that to be sure. I did and found at least with in visible light with an Olympus 50-200mm f2.8/3.5 lens the image quality was better with EC-14 and or MC14 than cropping.
Order from worst to best:
Cropping, internal 2x mode, EC-20, MC14+Ec14. So when I want a 200-800mm equivalent lens I place both EC-14 and MC14 converters.
The 1.4x ones seem magical in some way as the image is better with either of them on their own, than the base lens. This was fun discussion back on the four thirds forums. EC-14 seemed to improve the images out of the lenses that were coupled to it. The Mc-14 also seems to have similar magic with better coatings.

Edited by dabateman, 11 April 2021 - 14:07.


#4 Bill De Jager

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Posted 11 April 2021 - 19:18

In cases where the lens substantially outresolves the sensor, in principle a teleconverter of sufficient quality could give better results than cropping. In the case of the teleconverters discussed in this thread, sensor resolution is limited to 20 MP at most which I would not call high resolution by today's standard. As dabatemen noted the only way to be sure is to test the particular combination.

I have the MC-14 and was impressed by its quality when I tested it on the Olympus 300mm f/4 lens.

Edited by Bill De Jager, 11 April 2021 - 19:19.

Studying the botany and plant geography of California and western North America for almost 50 years.