The Ultimate Teleconverter Test

[Roy C]

Following successful trials with the 400mm f5.6 prime with 1.4 and 2x tc's I decided to try stacking the two converters to give a focal length of 1120mm (inc crop factor = FOV of 1792mm).
Attached shot is one of a dozen or so fairly good shots that I got but is the only one I have managed to upload. IQ suprised me a lot.
Please click on the image to view at full size for best effect


[IMG][/IMG]

[matt_xyz]

it's still pretty sharp isn't it?! I bet you didn't handhold this one!

I think it just goes to show that if you have an excellent lens in the first place then teleconverters can still produce good results.

Matt

[Roy C]

Originally Posted by matt_xyz

it's still pretty sharp isn't it?! I bet you didn't handhold this one!

I think it just goes to show that if you have an excellent lens in the first place then teleconverters can still produce good results.

Matt

Quite right Matt, I did not hand hold this one

I think you are spot-on when you say about the lens quality to start with. Any imperfections in the lens are magnified with teleconverters.

[nightshade]

Which ever make of lense you own they all perform slightly differently
my Sigma 70-300 seems very good at 200mm f9 (for its price)
If I were using a converter I would make this a starting point
the posted image is very very good what make are the converters

[Roy C]

Originally Posted by nightshade

Which ever make of lense you own they all perform slightly differently
my Sigma 70-300 seems very good at 200mm f9 (for its price)
If I were using a converter I would make this a starting point
the posted image is very very good what make are the converters

The 2x is a 15 year old Teleplus and the 1.4 is a Canon. I almost always shoot with the 400mm f5.6 wide open but this is the only lens that I have that does not benefit from being stopped down a tad.

[glsammy]

A very good shot, one I would have been pleased to get, with or without the converters. Looks sharp enough to me.
Looking at the exif data, it's F6.3, which is where I have to start with the Bigma!

[Roy C]

Originally Posted by glsammy

A very good shot, one I would have been pleased to get, with or without the converters. Looks sharp enough to me.
Looking at the exif data, it's F6.3, which is where I have to start with the Bigma!

Dont be fooled by the exif data Graham. The tc next to the camera was a non reporting type (8 pins only) so the Camera did not know there were any converters present. The two converters still lose 3 stops of light (one for the 1.4 plus two for the 2x). On my 5.6 lens this would equate to f16 by my reckoning.

[glsammy]

Originally Posted by Roy C

Dont be fooled by the exif data Graham. The tc next to the camera was a non reporting type (8 pins only) so the Camera did not know there were any converters present. The two converters still lose 3 stops of light (one for the 1.4 plus two for the 2x). On my 5.6 lens this would equate to f16 by my reckoning.

Ah, I'd forgotten you'd used an older type tc. Not much wrong with it though!

[Ollie]

It's a great shot Roy. Impressive I think for the use of stacked teleconverters. I have been thinking of getting a 1.4 teleconverter for my Canon 400mm prime and seeing what you have achieved with a 1.4 and a 2x together it makes me think that it would be worthwhile getting a 1.4 at any rate.
Roger

[Roy C]

Originally Posted by Ollie

It's a great shot Roy. Impressive I think for the use of stacked teleconverters. I have been thinking of getting a 1.4 teleconverter for my Canon 400mm prime and seeing what you have achieved with a 1.4 and a 2x together it makes me think that it would be worthwhile getting a 1.4 at any rate.
Roger

Thanks Roger - With the light being so good I have had the 1.4x almost glued on to the 400 prime for the last three or four weeks and use it hand held or with a monopod. You still have to get fairly near to the birds but it makes the difference for shots that would normaly be just out of range. A useful tool to have on one's armoury IMO. I have the Canon 1.4 but by all accounts the Kenko Pro is just as good and a darn sight cheaper.
Cheers
Roy