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Tokina RMC Doubler

Reviews Views Date of last review
4 15,784 Wed June 12, 2019
Recommended By Average Price Average User Rating
100% of reviewers $16.67 7.75
Tokina RMC Doubler

Tokina RMC Doubler
Tokina RMC Doubler
Tokina RMC Doubler

7 element TC, looks optically similar to other "MC7" teleconverters eg Vivitar, KAX, Aico....slightly longer in the barrel than my KAX 2x macro tc. Most commonly found as P-KM but does exist as P-KA.
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New Member

Registered: February, 2019
Posts: 10
Lens Review Date: June 12, 2019 I can recommend this lens: Yes | Price: $10.00 | Rating: 9 

Pros: It works really well on a quality 50mm lens to 105mm lens, boosting the latter to about 210mm
Cons: Nothing - unless you want miracles
Camera Used: Pentax K-X K2   

There are many ignored aspects to using teleconverter systems these days. First things first, none from the past and the present day will be a perfect 10/10. People genuinely assume they will all work on all lenses without and changes to image quality and aperture, and that as they generate more magnification they will not affect images - and not bring out inherent lens weaknesses - on an increasing level as you up the magnification range. These kinds of assumptions are not grounded in the real world of lens optics and the laws of physics. This is not a 1.4x or 1.5x converter. It is a very generous full 2x converter and it's damned fine for what it is. It's not going to be good on zoom lenses because they are the worst lenses to use with a converter, and many zooms are not top quality so the weakness of the lens will become magnified. But pop this on with a quality 50mm and you'll get fantastic increased focal range and no loss of sharpness across 80% of your central photos. Go to 80mm with a quality lens and things will be very good as well, but maybe over 70% of your central pictures. Go to 105mm on a quality lens and you'll see a little lessening of quality - if you are a faffy perfectionist - but not by a massive amount. Go above that to 150mm or start pushing your luck at 200mm and you'll see decline in sharpness around the edge and a central sharpness that is much reduced IF you can hold the increased focal length and increased light demands still enough for non-blurry pictures. What you won't get is a quality 200mm lens suddenly becoming a quality 400mm lens (something that in reality will cost you $500-$2000). Sorry, but that is a pipe dream for the $10 or $20 this will cost you! Nicely made, beautiful optics, richly and deeply multi-coated, easy to use. A lovely piece of well-made kit that takes up no space or weight that's more than an average 50mm film lens.
Site Supporter

Registered: November, 2012
Location: North Wales
Posts: 2,012
Lens Review Date: April 15, 2013 I can recommend this lens: Yes | Price: $20.00 | Rating: 8 

Pros: sharp, (so far), cheap and sufficient preservation of IQ to be worthwhile
Cons: As with all TC's: are you any better off than just cropping/enlarging your image??

[update 6/19] 2x Tc's make a big hit of two stops on exposure (meaning that if you are looking for a lot of reach with a telephoto, unless you have something like a 300mm f2.8 you are going to be already at f8 or slower), and will ruthlessly expose any optical shortcomings in the lens you use it with. These days I just about never use one for these reasons. However they can be useful in certain circumstances. One point to appreciate is that they do better with certain subjects - airplanes for example. Less well with subjects with lots of fine detail like birds. They can work quite well with fast standard lenses like the 50mm if you don't have a 100mm lens.

I think this is one of the better 2x tc's. I took some shots with my Tamron 60B 300mm 2.8 with this and with my 01F adaptall 2x tc. Looking at the results side by side I couldn't really tell the difference - essentially equal IMO, though more scientific scrutiny with a lens chart etc might have distinguished the two. I can say that by the time you have cropped processed and resized images, then comparing with images taken without a tc and processed to a similar result the gain you might get with the tc can be as much as 1.5x, or as little as no gain from using the tc, you will never realise 2x.

I didn't notice CA issues like the first reviewer. This seems like one of the better vintage doublers - certainly better than the kiron matchmate I also have.

Reading on the forums this is apparently the same as Kiron (and Vivitar) MC7, and was also sold as a NIkon. And I now have a KAF (also = vivitar) Macro MC7 and this also looks the same optically.
New Member

Registered: December, 2010
Location: Florida
Posts: 8
Lens Review Date: March 26, 2011 I can recommend this lens: Yes | Price: $20.00 | Rating: 9 

Pros: Sharp! Build Quality
Cons: Manual Focus

Gives me what I bought it for with no softening of the
image. I haven't noticed any CA or PF but it does cool the image, which doesn't bother me with the ability to tweak things on the computer.
Site Supporter

Registered: August, 2009
Posts: 387
Lens Review Date: November 24, 2010 I can recommend this lens: Yes | Price: None indicated | Rating: 5 

Cons: not particularly good IQ in combination with M 200

A bit disappointed with this TC, as I had looked around the internet and found positive comments about this one on I believe its a 7 element design due to its length. However, it did not perform well with the M 200: masses of CA and low contrast. So I would caveat my rating of 5 with the fact I combined it with a non-Tokina lens. There are some long Tokina lenses out there, and it may be the case that this TC works well with them. I'll never know, as soon as I saw its performance with the M 200, I sold it again. Cheap as chips, so no love lost.
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