400mm f5.6 and 2x teleconverter trial

[Roy C]

Dug out a 15 year old Teleplus 2x converter the other day and thought I would try it out with my 400mm f5.6 lens. I used a tripod and manul focus for all shots
Must say I was very suprised at the IQ which is much better than I expected. Focal length of 800mm with a FOV of 1280mm.
Please click on the image to view full size for best effect

[matt_xyz]

those are sharper than I would have expected as well Roy. The strong sunlight certainly would have helped to pick out feather detail. You are obviously good at focusing manually, or else these birds sat still for a long time! Did the autofocus perform worse than with a 1.4 extender or is AF not possible because this extender is old?

Matt

[Roy C]

Originally Posted by matt_xyz

those are sharper than I would have expected as well Roy. The strong sunlight certainly would have helped to pick out feather detail. You are obviously good at focusing manually, or else these birds sat still for a long time! Did the autofocus perform worse than with a 1.4 extender or is AF not possible because this extender is old?

Matt

Matt, I did not use AF as it was f11 remember so that is asking a bit much of a camera that is not supposed to AF over f5.6 (as we know we can push it to f8 with a 1.4 tc and taping the pins but that is about the limit). As I said I manually focussed but what a lot of people do not realise is that even when you switch the lens to Manual focus you can still get focus confirmation by the little red square and the beeb - without this aid I doubt that my eye sight would have been good enough.
Everthing that I have read says that 2x converters are almost worthless on anything less that a fast prime - I reckon these shots disprove this, not saying they are great but certainly not worthless.

[glsammy]

I'd have been delighted with these shots, with or without an extender!
When I tried one with my Simga 50-500mm, I was not impressed. Your shots are in a different league from the soft rubbish I got with my set up.

[Roy C]

Originally Posted by glsammy

I'd have been delighted with these shots, with or without an extender!
When I tried one with my Simga 50-500mm, I was not impressed. Your shots are in a different league from the soft rubbish I got with my set up.

Graham, I think it is just the difference between a Prime lens and a zoom. By all accounts there are very few zooms which take a tc well (Canon 100-400 being an exception). I have always got good shots with the 400 f5.6 prime and a 1.4 tc but never though a 2x would any good. I doubt if I will use the 2x a lot as it really needs a tripod whereas I can hand hold the 400 with a 1.4 tc.
For a bit of fun I will try stacking the two tc's to give a focal length of 1120mm and a FOV of 1792mm

[Jon]

Roy the results are very good indeed. The problem with converters is that they themselves introduce imperfections, simply by virtue of the fact that they have several different lenses of their own added to those of the main lens in question (e.g. diffraction, dispersion & chromatic aberration). Secondly they magnify any imperfections of the main lens. In your case the lens is an L series lens so the imperfections are relatively minor.

Going back 15 -20 years I do recall that autotelepus converters were amongst the best of the independent converters. I think the other good one was the Tamron - I think they had an SP converter. So maybe on reflection it is not unreasonable to get reasonable results, if you get my drift.
Jon

[Mexico]

Hi
I use an old Tamron SP300mm f2.8 which is only a manual focus. I also use the Tamron SP 2x converter but don't get results matching yours Roy. Having said that, this lens is from the early eighties so a little more than 15 years! It's a bit chunky to carry round, too, which doesn't help when light is at a premium. I've been considering the Sigma 50-500mm as, in places, it gets good reviews. Not so sure now I've seen GLSammy's comment, although was this only with the 2x converter Sammy?

Cheers,
Mex

[glsammy]

Originally Posted by Mexico

Hi
I use an old Tamron SP300mm f2.8 which is only a manual focus. I also use the Tamron SP 2x converter but don't get results matching yours Roy. Having said that, this lens is from the early eighties so a little more than 15 years! It's a bit chunky to carry round, too, which doesn't help when light is at a premium. I've been considering the Sigma 50-500mm as, in places, it gets good reviews. Not so sure now I've seen GLSammy's comment, although was this only with the 2x converter Sammy?

Cheers,
Mex

The Sigma 50-500mm is a fine lens, I love it. I've only about 1,000 images in the Gallery taken with it! It's just not too good when used with extenders, as has been said, you get the best performance with prime lenses when using them.