High quality teleconverters to fit various slr mounts. Full AF linking with most AF lenses. Highest quality Hoya glass. Available in 3 sizes, 1.4x 2x and 3x. Content and images originally posted by Andy Bright
Reviews
Andy Bright's review
I am using the Nikon N-AFs versions, 1.4x and 2x.
These teleconverters have been making a big name for themsleves over the last few years. Despite the cheesy reputation that Kenko has in some quarters, these use the very best Hoya glassware and are often rated higher than the similarly priced Sigma teleconverters.
Against older Nikon teleconverters, these can more than hold their own in clarity of image and have the benefit of being very AF friendly with many lenses, unlike many of the archaic Nikon tc's.
In use the 1.4x results in nothing more than light being reduced by 1 f-stop... degradation of sharpness and contrast isn't really noticable vs the bare lens. AF speed on a lens using USM/AFSII/HSM isn't seriously reduced, still very rapid.
As with most 2x tc's, the PRO300 2x does represent a compromise in quality over the bare lens, contrast and clarity do suffer. What constitutes unacceptable results will be a personal issue, but the images imho can still be full of intricate feather detail.
From my experience of 35mm and 2x teleconverters (300mm f2.8 + Nikon 2x) the results do look better but this could well be down to the digital age and the ability to sharpen and adjust levels in-computer. I personally think that teleconverters have far more value in the digital era than they had before.
Naturally, the extra 2 f-stops of light loss may mean the AF will fail to operate on many camera/lenses. Few cameras will reliably operate in AF when faced with greater than f5.6 (so even an f4 lens you're unlikely to get much in the way of AF with an extra 2 f-stops taking things to f8), you never know though, I have a 70-300mm f5.6 that works o.k. in AF with a 1.4x tc
I don't own the 3x...but you can imagine for yourselves that this is for the very desperate times. I have seen a full size image taken with the 3x and a Nikon 600mm f4 and it wasn't too bad... but you really do need the sharpest of lenses to start with...and watch out for vignetting.
Pros
- Cost
- compatability
- optical quality
Cons
- It's Kenko!
Doug Greenberg's review
I own all three Kenko Teleplus Pro teleconverters, the 1.4x, the 2x, and the 3x. I also own older Nikon 1.4x and 2x teleconverters. From my experience, the optical performance of the Kenko models is equal to the Nikons, and at a far lower price. Moreover, the Kenko Pro models have full metering capability with current DSLR models, plus screw-type autofocus capability that will work down to and even past f5.6. I have used the 1.4x teleconverter with my Nikon 80-400mm. VR zoom, and even at the equivalent of 560mm. f8, autofocus will function, albeit slowly. The VR function also works, albeit anemically.
Overall, for bird photographers looking to get more versatility and "reach" out of current telephoto lenses, these are the best available teleconverters (Tamron's "Pro" series apparently is identical, just with a different nameplate). I recommend them highly.
Most people believe that a 3x teleconverter is necessarily a kind of gimmick that can't possibly provide top-quality images. I have obtained some excellent pictures using mine, however, coupled with a 500mm. tele. That's 1500mm. of telephoto power!
The downside of these (and any) teleconverters is that they will magnify any optical flaw in the lenses being used. They work best on top quality, fast telephotos. If used with inexpensive optics, the results will be correspondingly disappointing. They also tend not to work well with zoom lenses. This is partly because zooms invariably have more optical compromises than primes, but also, I think, because adding five or seven additional optical elements to zooms already incorporating eighteen or twenty pieces of glass simply increases the likelihood of diminished optical performance.
Consequently, the 1.4x, for example, CAN be used with the popular "reduced vibration" telephoto zooms, but don't expect the same level of image quality one could achieve using a high quality, fixed focal length telephoto.
Another problem, of course, is that teleconverters reduce available light. A 1.4x will necessitate a 2x increase in exposure, a doubler requires opening up two full stops, and the 3x teleconverter requires three full stops additional exposure. This factor necessarily makes getting good images more difficult, the optical quality of the "rig" notwithstanding. If one is using a DSLR, the ISO setting can be increased. I have obtained quite satisfactory images using a Nikon 500mm. f4 lens with the Kenko Teleplus Pro 3x teleconverter with the ISO setting turned all the way up to "High 2," which is, I believe ISO 6400. The noise level in these images is unavoidably significant, but using a noise reduction program like Neat Image, one can produce finished images that are surprisingly satisfactory.
Still, when using teleconverters, particularly the 2x and 3x versions, the necessary use of slower shutter speeds will always be an issue. Consequently, using a very sturdy tripod and tripod head is a good idea, and taking measures to minimize "mirror slap" is also recommended. The Nikon D100, for example, has a special anti-vibration setting that delays exposure a few seconds while mirror vibration dissipates. For some kinds of bird photography (i.e., a bird that isn't moving around), this is a good solution.
Overall, the judicious use of these teleconverters adds tremendous versatility to one's SLR rig, providing that the lens(es) you use are of high quality and that you take the appropriate measures to achieve the best possible exposures you can get, given the limitations imposed by the use of teleconverters.
Pros
- Optically first-rate
- adds tremendous versatility to one's SLR capabilities
Cons
- Cuts available light
- demanding higher ISO or slower shutter
DiggitalD's review
After reading so many good reviews, I decided to try the Teleplus Pro 300 2X tc. When I got it - even knowing that it was a Kenko - I was still shocked at how poorly it was made. The cheap plastic housing and flimsy contacts made me wonder how I could spend $200 on such junk. I already owned a Sigma 1.4 tc which is super solid. I tried the Kenko anyway and was disappointed to find that the autofocus didn't work with my Sigma 100-300 f4 EX lens. It just zoomed all the way out, then all the way in, reeeeally slowly. This may be the fault of the tc or the Nikon D70's extremely poor autofocus system. I set the camera up on a tripod, manually focused on some fruit at different aperatures, a took a bunch of shots using a remote trigger. The images were all quite soft. The only pictures that weren't useless were shot around f11. I returned the Kenko a few days later. Even if Kenko is using Hoya glass, which is just decent, the build of this tc is still typically low-grade, knock-off quality.
Pros
- cheap
Cons
- you get what you pay for
