tele-extenders with XL1-s
 

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Well, I searched the archive, and no one seems to have discussed this so here goes.
I use the XL-1s with EF adapter and a Canon 75-300 zoom.
Nice sharp images. Occasionally I add a 1.4 teleextender between the EF adapter and the lens, and the image is noticably softer--unacceptably soft for wildlife close-ups. (OK, it's a Tamron, not a Canon extender, but I can't find a Canon to try locally).
All the still photo experts rave about how crisp their images are using any brand of extender, so the question is have any XL-1 folks been using these? Are your images soft, too? Is using an extender with a 1/3" CCD just pushing it too far? I also tried putting the XL-1's own extender between the body and the EF adapter. The image stinks.

Thanks for the input.

Steve Siegel,
Miami, FL
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FWIW: The tech manual for the EF adapter XL specifically recommends against use of extenders (even Canon's own EF 2x or 1.4x) with the adapter due to potential difficulty attaining good focus with "lenses which extend rapidly in accordance with the angle of rotation of the focus ring." Has to do with the optics and smaller circle of confusion with video. They suggest using an external monitor to check focusing if you have to use such a rig.

Also, the tech manual for the Canon Extender LX 1.6x states taht it cannot be used with the EF Adapter XL.

I have used the Canon EF 2X and 1.4X teles with good results. These tele-extender only fit specific EOS EF lenses because the front element of the extender protrudes beyond the lens mounting flange, into the body of the lens. The EF extenders will not fit the EF 75-300mm lens you own. Tamron makes two extenders, one is a fairly generic model that retails for between $75 and $100. It is a fair design and offers just OK optical quality. Tamron also sells a much more expensive flat field, 7 element extender. It uses better glass and it is of much better quality. As Don mentions, the focus with any of these combinations is extremly critical. The depth of field at 300mm and a 2X extender is only a few inches or less. I personally feel that the 1.4X is sharper than the 2X. This observation is purely subjective.

Jeff

Thanks, Don and Jeff for your replies.
You're right, Jeff, I forgot, the other reason I didn't use the Canon extender is that it only fits the white lenses. I am using the expensive 7 element Tamron, and indeed the depth of field
is really shallow. Maybe that's why the focus is soft. Oh, well, I'll just have to practice sneaking up better.

Thanks again,
Steve Siegel,
Miami, FL

Steve,

Practice, practice, practice, is what you have to do with these long tele rigs for the XL1. A very slight turn of the focus ring and the plane of sharp focus is way behind or way in front of your subject. I've been doing wildlife (mostly birds) this way since the late '80's. I've hundreds of hours of footage and years in the field working this way. Believe me, it was very discouraging in the beginning. Nothing was sharp. Florida provides some of the best training areas. Spend some time at the beach shooting shore birds and waders. The long expanse of beach, in front of and behind the subject will aid you in finding your plane of focuse when you review your tapes. The bird won't be sharp, but if you look close you'll see the sand just in front of or behind the bird is.

If nothing in the scene is sharp, you've probably got camera movement. I've had to fashion custom lens holders or supports (craddles?) to help hold the lens/camera assembly rigid. A big, sturdy tripod is a necessity. I use a Vinten, but Sachtler, Miller and O'Conner all make suitable tripods for nature field work. In the past I've found the Bogens to be too light. I understand they have some very new sticks and heads that may be suitable.

Jeff