I am looking at buying a teleconverter for my Pentax 6x7. I would be interested in opinions on the Pentax 1.4x vs. the 2x. This would be used with my 200mm lens. I have held the Kenco 2x teleconverter and didnt like the feel of it. I am finding I need a little more magnification at times, but have not convinced myself to buy the 300mm (and I can only dream of the 400/4 ED and may need to save some money for the new version of the Pentax 6x7).

Thanks, Steve Cook

-- Steve Cook (cooksa@cu.imt.net), September 20, 1998

Answers

My brother had sent a letter to Pentax asking for a sharpness comparison between the 300mm vs the 200mm with the 1.4x converter. He got no response. It is my opinion that the 300 is unsharp due to excessive overhang from the tripod(lens barrel wag) and inaccurate DOF scale on the lens barrel. I have taken sharp images with it, so I know it is optically capable. The 200 with the 2x may have the same overhang problem that the 300 has alone. The 200 with the 1.4 shouldn't be as long as the 200/2x combination so it would have to be sharper. Sorry that I don't have any test data that I can share with you on this. SR

-- Steve Rasmussen (srasmuss@flash.net), September 20, 1998.

Steve,

I do not have either of the converters, but remember the teleconverter dichotomie: the more you take, the more you lose. A 1.4 will degrade the image less than the 2x. Go with the lesser power if you are more concerned about quality than reach. A converter only magnifies the shortcomings of the lens you put in front of it, so consider that as well. Sorry if I am telling you things you already know.

Happy shooting.

Jim Korczak

-- Jim Korczak (korczaks@ptdprolog.net), September 21, 1998.

I own the 1.4 teleconverter and have been very pleased with it. I use it exclusively on the 200mm lens. I bought it in lieu of the 300mm lens simply because of weight and size considerations. It's much, much easier to carry the teleconverter rather than the 300mm lens, which is quite large and heavy. I would have to have bought another back pack to accomodate the lens, but the teleconverter is small enough that I could use it with my existing pack. I haven't used the teleconverter as much as I thought I would but on the occasions I've used it I haven't noticed any image degradation in prints up to 11x14. I haven't, however, at this point conducted any serious comparison tests say of the 200mm lens alone and with the teleconverter added. I bought the 1.4 rather than the 2x partly because of the greater f stop loss with the 2x, partly because I thought there would be less image degradation with the 1.4, and to a lesser extent because I suspected, without really knowing, that the 2x would be larger and heavier than the 1.4 (if this had been a major consideration I would have checked, but it wasn't and so I didn't). The 1.4 is very easy to take on and off the lens and appears to be very well constructed. All in all I would highly recommend it if the 80mm extension (on the 200mm lens) is enough for you.

-- Brian Ellis (beellis@gte.net), September 30, 1998.

Has anyone experience with the 1.4tc on a 165mm LS? f8-f16 with flash if that matters.

-- shawn gibson (SeeInsideForever@yahoo.com), January 28, 2000.