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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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Teleconverter shootout Canon 2xB v Kenko Teleplus Macro MC7
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Today the postman brought Canon 2xB and I wanted to compare it to Kenko teleconverter that I've had before. Both are 7-element 2x teleconverters. 2xB is Canon's teleconverter for lenses with FL < 300mm with FD mount. Kenko is likely the best general purpose third party teleconverter. This converter is available in different mounts and under different names. Thanks to its own focusing helicoid it converts a Canon normal (e.g. FD 50/1.4) into 1:1 macro. However, I tested only long distance performance.

Test conditions: E-PL1 m4/3 camera, heavy tripod, 12 seconds delay, the lens is Canon FD 200mm f4, the images shown are SOOC jpegs, no postprocessing. Due to crop factor, the effective focal length is 800mm. Click on the images to get access to full size originals.


#1 Canon FD 200mm F4 @ f8. The distance to the target is about 0.5 km.

#2 Canon FD 200mm F4 @ f8 + Kenko 2x

#3 Canon FD 200mm F4 @ f8 + Canon 2xB


#4 Canon FD 200mm F4 @ f8. The distance to the target is about 60m.

#5 Canon FD 200mm F4 @ f8 + Kenko 2x

#6 Canon FD 200mm F4 @ f8 + Canon 2xB


The distance to the target is about 15m.
#7 Canon FD 200mm F4 @ f5.6 + Kenko 2x

#8 Canon FD 200mm F4 @ f5.6 + Canon 2xB



Here are the last two images with my standard processing (more contrast curve + minimal sharpening).

#1 Canon FD 200mm F4 @ f5.6 + Kenko 2x (processed)

#2 Canon FD 200mm F4 @ f5.6 + Canon 2xB (processed)


Conclusions. Both are excellent tele-converters, I don't see them degrading the image compared to the original lens. Between them, I don't see any IQ differences worth fussing about. This makes Kenko that has its own helicoid and is cheaper an amazing deal. On the downside, Kenko is fat. If you attach the tripod to the camera mount, Kenko is a lot less convenient to operate as it might rub the tripod plate (depending on your tripod). Canon is flush with the mount, no issues here.


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Lot better result what I had with Tamron TC, usable indeed.


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Which Tamron TC did you try?

After the test I've also got Canon 2xA. Now I am waiting for an adapter screw to put my Tair-3 on tripod, then we will see how many converters Tair will take and what kind of moonshot it will produce Twisted Evil


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Thanks for posting this.
The results are virtually identical to my eyes.
Kenko would appear to be a good buy.
Cheers
OH