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Home >> Photography >> Accessories Lens Accessories Tamron SP Pro 300 Series 2x Teleconvertor
Despite having the teleconvertor for some time now, I have not found much need for a 400mm lens all that often since I do not stalk wild critters and avian photography bores me to tears (but I respect the work of Moose Peterson and Arthur Morris very highly as they are superb at what they do). I still desire a true long telephoto lens but unless my style and subject changes the Tamron teleconvertor will see me through the odd time I need the extra reach. I consider this writeup as a work in progress as I wish to try the teleconvertor with a prime lens to compare with the results using the 80-200mm lens before concluding the report. A last note for now, Tamron teleconvertors are EXACTLY the same as the Kenko Pro series teleconvertors. All that is different is the brand name as these teleconvertors are OEM products from Kenko. 0.42x Fisheye Style Adapters - June 1999
Anyway, the only item of interest I saw in his bag was this fisheye adapter that would turn any lens with a 52mm filter mount into a wider angle lens with pronounced distortion around the frame edges. My school chum Riaz also has a similar type of accessory and from what I can remember they are very similar. Riaz’s also had the ability to be reversed and used as a macro device. I’m not sure if Ben’s can do the same; I’ll try it later on. When I put the adapter onto my 50mm lens, it gave a wider perspective then my 24mm lens. With the original 50mm, I would still be able to use the whole frame. Put the adapter onto my 24mm though and I end up with a very small circular fisheye image that only fills about half of a 4x6 print but with an ultra wide perspective. I can shoot straight ahead and get my feet in the shot if I desire. I don’t know if that is considered 180 degrees or not. The image quality sucks with the adapter and the wider perspective makes the lens very sensitive to ambient light (flare?). Using it on my 24mm with flash will over expose with normal TTL settings. I haven’t played around with it long enough to figure out how much minus compensation to dial in. But this adapter is a lot of fun. It gets you out of the easy chair and throw the Popular Photography issue on the table and up and around shooting for and from a whole new perspective. Isn’t that one of the reasons why we shoot?
Tamron MC-4 1.4x Teleconvertor and Kenko MC7 2x Teleconvertor
The Kenko MC-7 2x Teleconvertor was purchased first from the used shelf at Leo’s in downtown Vancouver. I thought wow, only a hundred dollars and I could double my reach, great. I didn’t know much about teleconvertors back then and their attendant problems or compromises, especially cheap third party makes. The Kenko is autofocus capable and has seven elements to allow for a doubling of the focal length reach of a lens with the usual loss of two stops of light transmission. When I bought the Kenko I still had the consumer oriented 80-200mm f4.5-5.6 zoom lens so you could imagine the rather deplorable images that I would have received using the two together especially wide open but for some reason I never bothered to. It wasn’t until I bought the pro oriented 80-200mm f2.8 zoom lens that I actually did use the Kenko TC for some serious shots. The first time, I was at a friend’s house for dinner and came prepared with my equipment for some shots of his view of downtown. I had previously noticed his view and marveled at such a wide-open landscape of one end of downtown with BC Place Stadium to the other including the Lion’s Gate Bridge and the North Shore. Since my friend’s house was quite a distance from downtown I knew that the 80-200mm zoom lens would be the one to use to try and isolate certain parts of the scene instead of using a wide-angle lens and capturing everything in miniature. I started off with the 80-200mm lens by itself and then added the Kenko TC for some more shots on the same roll of Velvia film. I liked the way the Kenko TC helped to crop in tight to various parts of the overall scene and took quite a few shots isolating the marsh mellow-topped BC Place and the surrounding skyscrapers. But upon receiving the slides back I was disappointed by the way the Kenko TC had negatively altered the scene vis a vis shots without the TC being used. The 80-200mm lens gave me very clean colors with good delineation of details and was what I had expected of the scene. I took the shots during twilight so that an abundance of blue was in the air. It was a good compromise to shoot during that time because I personally happen to be attracted to such cool looking scenes and because the haze from the afternoon sun served to provide ugly atmospheric conditions for anything prior to twilight. Probably would have made for a good sunset but then I would have had silhouettes instead of lit up buildings. I don’t really like completely dark night shots either so twilight it was. The shots using the Kenko TC had very poor color rendition as compared to the lens by itself. A certain fuzziness was apparent but that could be a result of the increased magnification causing some problems via shake. I used the Manfrotto 55C tripod and Manfrotto 141 Pan/tilt head with the legs of the tripod fully extended. I realize that such a combo would not be the best setup for super telephoto applications and the shake problems were probably compounded by the lack of a mirror lockup on my F90x even though I used an electronic cable release. Be that as it may the way the color of the scene became degraded caused me to shelve the Kenko TC to be only used for experimentation and other low quality shots. I should note that when I used the Kenko TC with the same 80-200mm lens for a few quick shots of the Lions (twin-peaks overlooking Vancouver). I used the much more stable Manfrotto 075 tripod and the similarly massive Manfrotto 229 Pro Pan/tilt head in cool but calm conditions using the F90x and a cable release and I detected the same kind of fuzziness that I had gotten from the other shoots. Atmospheric conditions? Lack of mirror lockup? I can’t be sure but it’s enough of a nuisance that the Kenko is essentially a non-factor for my shooting needs. The Tamron MC-4 1.4x Teleconvertor was bought a little while after I bought the Kenko. You would think that I would have learned from being burnt by a cheapo product but at the time I couldn’t bring myself to spending nearly a $1000 for the Nikon TC14B, a unit that has garnered a great deal of praise for not degrading the optics of the lens being used with. But the TC14B is not autofocus and stupid me wanted AF capability out of a TC for use with my 80-200mm lens. This is even more ridiculous when you consider that the one touch zoom/focus version of the 80-200 f2.8 AF-D is already a slow AF lens. Add any third party TC to this lens and the AF becomes painful with a great deal of hunting trying to lock on to the subject or for that matter, any subject. Then consider that most of my use with this lens has been for scenics mounted on a tripod where AF is useless and in fact not desired so you could see that buying the Tamron MC-4 was wrongheaded in many ways. But I still bought it. I detect a little less degradation of the shots with the Tamron but still when you only pay $150 for a TC you can’t expect it to match the quality of a TC costing $1000. Another one for the dusty shelves. It’s here that I should mention my suspicion that all Tamron and Kenko teleconvertors are actually made by the same manufacturer and are basically identical except for the name brand. Looking at the Kenko and Tamron TCs, even though they are not of the same magnification, reveals exactly the same outside cosmetics and even the same type of name designation. That is the Kenko TCs are the MC-4 and MC-7 for the 1.4x and 2x units respectively with the numbers representing the number of elements used in the optical formula. The Tamron TCs are also the MC-4 and MC-7. Both offerings are low cost and low quality and unable to match the quality of teleconvertors made by an original company. However, both Kenko and Tamron have recently introduced new pro versions of the teleconvertors, which use APO, or low dispersion glass elements for superior quality and better matching of the telephoto lenses they are suppose to mate with. These lenses of course generally use APO or ED glass elements to enhance the quality of the image and logic dictates that you would want to use APO or ED teleconvertors too. Looking at both companies’ products on their respective websites and I see the same situation as with the cheaper TCs, identical specs and cosmetics. Because Kenko introduced their Pro 300 TCs first followed by Tamron with their Pro TCs a few months later, I suspect that Kenko makes the TCs for both companies with glass supplied by Hoya. This worries me to a certain extent. It leads me to believe that Tamron buys its glass from Hoya for their lenses and frankly I have never been impressed with Hoya glass. Their line of HMC filters seems to be inferior to B+W filters not only optically but physically too. If Tamron gets it glass from Hoya then so too perhaps would Bronica which is owned by Tamron. I don’t think I have anything to worry about but it does irk me to a certain extent. The Pro 300 series of TCs however, seem to have garnered some early positive comments and look promising. They are supposedly very well matched to the older Nikon telephoto lenses that do not use Silent Wave Motors so it could be something for me to look into for my older 80-200mm and Micro 200mm lenses. Kenko Auto Extension Tubes - December 30, 1999
The basic optical theory is that for life-size reproduction (1:1) of an object on a frame of film requires the same amount of extension as the focal length of the lens. So for our standard 50mm lens, 50mm of extension is required to achieve 1:1 enlargement on film. The beauty with tubes is that they are cheap compared to real macro or in Nikon speak, Micro lenses. I bought my first tube used again from Leo’s for a $100. I think I got taken but it is the PK-13 and provides 27.5mm of extension. Good enough to get 1:2 magnification with my 50mm lens. Speaking of which, I also bought my 36mm extension tube for my Bronica SQ-Ai system from Leo’s too but it cost me dearly at $300 but that’s still half the price of new. This is one accessory that Bronica needs to give some further thought to as they are suppose to be a more cost effective alternative to Hasselblad yet their tubes cost more then pretty much any other manufacturer on the market including Hasselblad and Rollei. I also bought the Kenko Auto Tube kit for my Nikon kit from Leo’s too but at a very good price. The tube kit comprises of three tubes of 12mm, 20mm and 36mm all of which can be used individually or any combination together. The cost of the Kenko tube kit was about 50% less then what it would normally sell for in Canada and my regular dealer had such a hard time believing it was true because it would be much cheaper then his cost. He couldn’t accept that it was true and refused to match the price so I went back to Leo’s for the purchase. I suspect that Leo’s bought a quantity of the kits from a US source and bypassed the regular distribution channels in Canada. A number of larger stores do such things when a product is demanded but not available in Canada. The NPC Polaroid backs as an example are not distributed in Canada but are available when a store like Vistek or Leo’s brings them up by themselves. Anyway, I like the Kenko tube kit for the cost effectiveness of it compared to Nikon’s regular Micro lenses of which the 60mm f2.8 is the cheapest at about $650 CAN and the 105mm f2.8 is about $1050. The 200mm f4 lens is very, very expensive at roughly $1800 but all three lenses provide 1:1 magnification by themselves. I wanted to buy the 105mm for the compromise in cost and working distance to the subject. This leads into one of the downsides of the tubes; the working distance is abysmal as you increase the magnification closer to 1:1. Add to that the effect of light bouncing around all over the place traveling down the tubes and lens to the film plane and some degradation is going to be insinuated onto the film. Since buying my used 200mm f4 AIS Micro lens, I’ve had less use for the tubes. My 200mm lens only gives me 1:2 magnification but the beauty is the 2’ working distance I have between the subject and film plane. If I really need 1:1 then I could do the silly thing and attach all of my tubes to the 200mm lens and get 95.5mm of extension but better to use a 2x TC and get a 400mm 1:1 macro lens with the 2’ working distance intact. Trick is to buy a good 2xTC to mate with the lens so as to minimize the degradation inherent in adding another chunk of glass to the lens for the light to travel through. The tubes I have, both Kenko and Nikon are not the most solid pieces around but they’re not going to fall apart anytime soon. I just feel that way about anything with significant plastic content but in both cases the plastic is on the outside. They’ll do fine for fieldwork when needed but again since buying the 200mm the tubes aren’t going to see much in the way of use. Unless or course I really want to get down and dirty with my subject for 1:1 with the 50mm and the scant inches I have to be way from it. As for the autofocus capability of the Kenko tubes, well son-of-a-bitch it works but with enough limitations that I don’t feel it to be worthwhile. First the AF is relatively quick with the individual tubes and my 50mm f1.8 AF lens but you have to be within the focusing-throw of the lens to subject. Meaning that you have to be so close to the subject that normal shaking from your hands or body will alter the focusing, wildly at times given how many (drinks) you’ve had before deciding to do macro shots. As you add more tubes for greater magnification the amount of working space diminishes and AF becomes more useless as it begins to hunt rapidly and again any attempts at handholding are for the stupid. Put the setup on a tripod and you’ll be forced to work more slowly optimizing the focus plane desired to which point AF becomes redundant. I should note the other wide use for extension tubes. Not only for macro, but for something as mundane as reducing the minimum focusing distance of a lens. Say you have a medium format 150mm lens that is classically known as the portrait lens for providing the shooter with a flatter perspective as well as a comfortable distance to the subject. But you realize that the 150mm lens can’t get close enough for a tight head and shoulders shot as it has a minimum focusing distance of about 1.5 meters or 5 feet. What do you? If you had a pocketful of change burning a hole in your pants then you go out and buy a 180mm lens that has the ability to focus to 1 meter and provides you with 30mm more magnification. If you’re poor like me you don’t think about buying another lens costing a couple of kilo bucks plus change. Instead you keep your eye out for an extension tube that will reduce your minimum focusing distance of the 150mm lens and will provide you with a tighter headshot. Now of course that was my exact situation above and I bought a 36mm tube when I saw it available but 36mm is too much extension for headshots unless you like to get more funky and abstract and do the half cut off face CD cover shot that seems so popular nowadays for female singers. Me, I’m still too cheap and pissed off at Bronica to go out and pay $600 for an 18mm extension tube and will try to wait out some guy wanting to sell off his Bronica accessories.
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Correspondence & About this website Copyright © 1998-2008 Edwin Leong |
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Just
some cursory comments on the quality of the Tamron teleconvertor as
used with my Nikon 80-200mm f2.8 lens. If you are looking for a 400mm
f5.6 lens on the cheap, you will get it but just be very aware that
the best resolution of this combination is at f11, i.e. stop down to
f5.6 on the lens' aperture dial or on your two-command dial Nikon body.
The Tamron does NOT work fully with the Nikon F100 body to transmit
the effective aperture being used in the viewfinder or top LCD display
however, the camera WILL caculate the correct shutter speed for the
effective aperture. You do not need to worry about underexposure with
the teleconvertor, even when using Matrix metering - at least that is
my experience with this teleconvertor, other opinions may be to the
contrary.
I
would like to own the Nikkor 16mm fisheye lens but at $1000, it does
seem a bit frivolous to spend that kind of money for a lens that won’t
see much action. For the time being I’ve "borrowed" my brother-in-law’s
fisheye adapter. This is not the one who bought my first F70; that’s
Kelly. This one, Ben, bought into an entry-level Yashica manual focus
camera. He bought it while visiting Honk Kong and in the process of
buying his kit, he went from one store to another to pick up a few other
accessories. I’ll try to do a write up on his kit some time in the future. 
I
wish I had more to say about these two products but I just don’t. They
were bought relatively early in my photographic journey and since their
initial first use have not seen much action. Why? The quality is not
very good at all and is so inferior to a prime lens or good zoom by
itself that I would say that it’s in order of magnitude how bad these
two products are. And you don’t need a loupe or enlargements to see
the inferior quality as the naked eye can easily distinguish between
shots with or without the teleconvertors attached. In essence you get
what you pay for and I didn’t pay a lot for these items. It also should
serve as a warning to always try the product first before buying. 
I have even less to say about these products as I did for the teleconvertors.
What can you say about tubes? Hollow tubes that may have some data
connections to mate with TTL and Distance information and hell, even
autofocus capability as with the Kenko tubes but they are nothing
more then just tubes to extend the amount of space between a lens
and the camera body. Simple, that’s it.
