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Takumar-A 2x Tele-Converter

Reviews Views Date of last review
8 30,838 Sun October 14, 2018
Recommended By Average Price Average User Rating
50% of reviewers $34.75 5.43
Takumar-A 2x Tele-Converter


This is a Pentax 2x teleconverter with KA mount lens information contacts. It doubles the focal length of the attached lens at the expense of loss of 2 stops of light.

Features of this teleconverter:

  • Manual Focus
  • Supports Tv or P exposure mode (in addition to M and Av), if the camera allows
  • The converter does not transmit focal length and MTF information from lens to camera
  • Can be used with most if not all lenses

Takumar-A 2X Tele-Converter
©, sharable with attribution
Image Format
Full-frame / 35mm film
Lens Mount
Pentax K
Light Loss
2 stops
4 elements, 3 groups
Mount Variant (Rear)
Mount Variant (Front)
Weather Sealing
Dedicated hard case
Diam x Length
60 x 25 mm (2.4 x 1 in.)
113 g (4 oz.)
Production Years
User reviews
The converter does not retain the autofocus capability of the attached lens, focusing is manual only.
The converter retains all exposure modes supported by the attached lens.
The converter does not relay information about focal length, MTF, or lens name to the camera.
The converter can be used with most if not all K-mount lenses.
Automatic ApertureFull-Frame SupportDiscontinued
Price History:

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Loyal Site Supporter

Registered: December, 2012
Location: Spring Branch, Tx
Posts: 380
Lens Review Date: October 14, 2018 I can recommend this lens: No | Price: $15.00 | Rating: 3 

Pros: Has A contacts
Cons: Has a lens in it

I bought this just for the mount, almost never used [soft is not the word for the images out of this converter] and perfect for a worn A lens mount. I decided to de-glass it today and it is now an auto extension tube. It only took 20 tries to get all the pins and the lens release spring stop [ this was the issue, all the data pins all went in easy ] in place....

Registered: August, 2012
Posts: 527
Lens Review Date: January 12, 2018 I can recommend this lens: No | Price: $15.00 | Rating: 6 

Pros: Extends lens reach
Cons: Excessive loss of sharpness

This little accessory takes me back to the very beginning of my 35mm SLR days when the first lens accessory I got was a Kmart Focal 2x teleconverter for the 50mm lens on my Minolta X-570. It extended the lens' reach but at the cost of a lot of sharpness. This one does exactly the same thing for my Pentax-KA 50mm f2.0 lens. This convinces me that this teleconverter was designed with for the modest purpose of providing a cheap way of doubling the focal range of a 50mm lens in somebody's starter kit.

I got this teleconverter for two reasons--it has a KA mount so it will allow more or less full functionality with the aforementioned 50mm lens and it was very inexpensive. That's a good thing since it really isn't adding any new functionality to my kit, which contains a number of better options in the 100mm range. Given its lackluster performance, I have no intention of trying to use it with any of my autofocus lenses, so it was really more of a nostalgia buy than anything else. The only reason I gave it a 6 out or 10 is that I knew what I was getting into and it thus met my realistically low expectations of its performance.

Note: This teleconverter came to me bundled with a Vivitar 50mm f2.0 lens so the $15 price shown above represents a portion of the $27 I paid for the two items together--$15 for the teleconverter and $12 for the lens--arbitrarily determined by the two items' relative value to me. The true cost of this teleconverter will be determined once I sell off the redundant lens and subtract that from the purchase price.
Site Supporter

Registered: October, 2016
Posts: 90
Lens Review Date: December 12, 2016 I can recommend this lens: No | Price: $25.00 | Rating: 4 

Pros: Extra Reach
Cons: Turns sharp lenses soft

I bought this thinking that if I could turn my 55-300mm into a 600mm I could get more range at a small drop in sharpness. Wrong... This 2x teleconverter
softens shots to almost unusable. I found that it only takes decent shots in the best of light. I really wanted more detail in my moon shots and I found that no matter how much I tried to tweak the manual focus I could not get a decently sharp shot. This will go into a drawer and I will work on plan A again which is to get a lens with a native 400 or 500mm focal length. Only decent shot I took is below.

Senior Member

Registered: January, 2016
Posts: 241
Lens Review Date: February 28, 2016 I can recommend this lens: Yes | Price: $35.00 | Rating: N/A 

Pros: Gives you 2x if needed
Cons: Very bad flaring under light

I ended up with 2 of these recently, one that I purchased on Ebay for about $35 and the other was attached to a telephoto that I also bought from Ebay. Main reason I got these was because they have the contacts so that the camera body can still control the aperture for "-A" lenses.

These actually worked pretty well. Here's a shot I took with a 100mm FA lens and one of the 2x TCs.

The above shot was taken on a cloudy/rainy day, outside, and I had an umbrella partially over my head.

But then, one night, I was messing around with this TC and a DA 35mm lens, and found that when I shot while I was sitting under the lights above our kitchen table I'd get really bad flaring:

I posted about this here:

As mentioned in that thread, i was able to eliminate most of the flaring by using a makeshift hood and got:

So if you get this TC and use it under, say, direct sunlight, be aware of flaring, and if you get it, consider either using a hood, or moving to a shady spot !!
Site Supporter

Registered: July, 2012
Location: Mosquito Creek, Australia
Posts: 2,288

1 user found this helpful
Lens Review Date: April 23, 2013 I can recommend this lens: Yes | Price: $50.00 | Rating: 7 

Pros: Cheap, can give a useful image within limits
Cons: CA, not for pixel peepers

I picked up this tele-converter in a trade which would have valued it at about $50. Tele-converters are a mixed bag and this one does not have the best of reputations. However, I thought it would be worth testing so that its performance can be roughly benchmarked. The images below give a fair indication of its capabilities. All pics were taken with a K-01 with aperture set manually.

The first set is of a rose bud in the backyard. The first image shows the bud in the centre of the full image. The next two are 100 per cent crops of the central bud taken at about 10 metres with a Tokina rms 400 mm f5.6 (stopped down to f11) and a Pentax M 200 mm f4 (stopped down to f5.6) with the tele-converter ( the effective aperture with the tele-converter is f11). The third image is a 100 per cent crop of the rose bud taken with the Pentax M 200 mm f4 at about 5 metres.

The Tokina has a sharpness rating of 8 from reviews on this site. The Pentax has a sharpness rating of 8.5. Looking at the first and third images, these seem reasonable ratings. The second image, with the tele-converter, shows lack of sharpness and considerable CA. There is also some loss of contrast (the Takumar-A is not SMC).The image degradation caused by the tele-converter is evident. But these are 100 per cent crops. Reproduced on a13 inch monitor (at about 80 dpi) this is the equivalent of a print about 60 inches wide. This is not what the tele-converter would be used for.

So does the Takumar-A 2x Teleconverter have a place in the camera bag. I believe it does. Imagine you are in the wilds of Australia (like my backyard) and your 18-270 zoom dies. What do you do? Reach into your camera bag and pull out theTakumar-A fitted to a suitable 200 mm or 135 mm lens and continue shooting. The final two images are of a female common wallaroo shot (in the backyard) with the Takumar-A and Pentax M 200 mm f4 on the K-01. The images are 20 percent reductions. They are sharp enough at that size.I would say they are good enough to salvage holiday memories unless one is a compulsive pixel peeper. If one comes up at the right price the Takumar-A 2x may be useful to have in the bag for emergencies or unexpected opportunities.

New Member

Registered: September, 2010
Location: Mississauga
Posts: 3
Lens Review Date: April 12, 2011 I can recommend this lens: Yes | Price: $93.00 | Rating: 7 

Pros: Cheeper than buying a telephoto lens
Cons: I think I payed too much for it

I bought this tele-converter at Henry's Outlet in Mississauga Ontario for about 89.00 CDN.
So far I'm happy with the teleconverter, as I'm having fun with it. I think with proper lighting and the right situation I can get some interesting images.

Overall the images produced with it are acceptable.

Here is the first shot I took.

As a photographer I still have a long way to go. But in terms of this tele-converter's performance I think the level of detail and image quality are just fine for my purposes. Since I am a beginner amateur/casual level photographer.
Loyal Site Supporter

Registered: September, 2010
Location: Hudson Valley, NY
Posts: 1,755
Lens Review Date: September 22, 2010 I can recommend this lens: No | Price: $30.00 | Rating: 4 

Pros: Allows A setting to be used in K7 camera

I was looking for an "A" type teleconverter to use with some older prime lenses that I have for the K7. I have a Vivitar 2x but it does not allow operation in the "A" setting. When I put on the Pentax Takumar A converter on the lens, everything seemed soft! When I switched to the Vivitar 2x, it was sharp! I cannot recommend the Takumar teleconverter unless you are trying to do soft focus work!

Tried the teleconverters on both a SMC 50mm 1.7 and a 135mm 2.5.


Registered: January, 2007
Location: Toronto
Posts: 15,518

1 user found this helpful
Lens Review Date: May 8, 2009 I can recommend this lens: Yes | Price: $15.00 | Rating: 7 

Pros: low cost TC has apature contacts
Cons: there are better TCs out there

picked this up only because it had the apature contacts. I don't really use it, just thought for the price why not.

one thing to note is that while it has apature contacts for the A series lenses, it has no intelligence, apature data is fed straight though which will result in exposure errors on the K10D due to metering.
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