Stacking a pair of kenko TC's (1 Viewer)

Its the first time that I stacked TC's together, and no doubt many may have posted something similar before, so please forgive me.

I borrowed a friends kenko 1.4x tc dgx 300pro and stacked it together with mine, and mounted it onto my skywatcher ed80. Took it out for a quick shooting.

The results seems ok for me and I'm happy with it and surprised that it produced sharper images than when i was using 1 kenko TC? Has anyone experienced something similar?

Just by using 1 kenko TC with max dslr and 50mm extension tube, I can see some pretty noticeable vignetting in the corners.

But, when I added the 2nd kenko to it, the vignettings gone, and the picture seems to look better.

Here is the link to my photos, and the last 7 are the ones shot closer. Some were just shot like that.
Some light PP was done to the pictures

http://www.dpreview.com/galleries/9497779571/photos

Cheers

Is the 1.4X designed for full frame sensors or just the smaller crop sensors? I don't get any vignetting on my Canon 450D for example. As for stacking you can go up quite high and still get ok images. There comes a point where cropping the image is probably the best way to go rather than increasing magnification. I've gone up to something like 6X and still got sharp photos but the loss of light isn't worth it. About 2.5X is as far as I go if conditions permit.

The baby Robin looked nice. Haven't seen in my garden yet this year, had 4 baby Blackbirds and one newly fledged Dunncok so far. The female Blackbird has also started a second brood just a week after the last 4 left the nest so we'll have some more to save from the local cats in about 10 days.

Paul.

Hello Paul,

I don't know what sensor it's designed for? But on my friends rig, he gets no vignetting, regardless of 1 or 2 Kenko's stacked together.
My colleagues kit: ed80 DX pro and Nikon D300s DX sensor & 1.25" tubing.

But on my D3s FX sensor, max dslr adapter and 2" 50mm extension tube, I experience vignetting on the corners with 1 Kenko 1.4x. But I get zero vignetting when I add another 1.4 Kenko on!

But mounting the Kenko or two onto my Nikon 70-200mm f2.8 vr2 (fx lens), there is no vignetting.

So, i really have no idea if the Kenko is better for DX or FX? Mind boggling.

Nice to chat with you as usual.

Thanks

Is the teleconverter mounted straight to the camera?

If you have a macro tube then you can mount that between the camera and teleconverter. That will increase the size of the image circle from the teleconverter which might eliminate any vignetting and also it will give slightly more magnification. In my own tests something like a 45mm macro tube will extend the 1.4X to 2x mag. You can get a fair bit of extra magnification out of a 1.4X teleconverter by adding macro tubes between it and the camera.

Paul.

I have the 1.4 Kenko on the camera body, then the max dslr adapter to a 50mm 2" extension tube.

Hmm..... I'll try a macro tube, as they are quite cheap to buy.

Do I need to change my cameras non CPU lens info?

Cheers bud.