will this combination work?
 

1. Canon XL2
2. Canon EF Adapter
3. Canon 2X Extender ll
4. Canon EF 70-200mm f/2.8L IS or Canon EF 28-70mm f/4.5L IS

I am really trying to find out if the 2X etender will work with the EF Adapter, also does anyone know what the multiplication factor of the EF adapter is?

Without looking it up, the EF adapter is like 7.75x for 16x9 and 9.6x for 4x3.

Have a look at http://www.dvinfo.net/canonxl2/articles/article10.php for some comparisons. That article shows the use of the 1.6x extender with the EF adapter.

I've got the 2x but not the EF so I don't know if that will work...

lol dude imagine the 70-200 f2.8L @ fulll tele with the XL adaptor (and the 2x extender if it works)

what do you plan to use this combination for?
apart from that, lovely glass.. stuff i dream for!

julz

Wildlife video, my 20X optical isn't even getting close out here, I really need to be able to reach out. I ordered the 70-200 and 100-400 last Friday, just waiting for them to arrive, (along with the 2X extender)

I have 1, 2, and the 70-200mm f/2.8L. That lens is wonderful, and I've got some great footage of the moon, far-off fireworks, birds/insects/plants, etc.. It has to focused manually (as you probably know), which is a little difficult with the standard viewfinder, but it works well with some practice.

Hi Chris,
I asked related questions on this subject at the nature sub forum,
I got a lot of answers from people using EF adapter.
http://www.dvinfo.net/conf/showthread.php?t=66301
I am using SLR lenses on my xl1s for a few weeks now, and this is what I think
as one using the maximum magnification my equipment allows me (shooting birds).
The 100-400 will do the job for you, the 400 end will translate to 3000mm or 4000mm (slr world) , with that magnification you will need a good tripod
and a very good video head and yet a smooth pan will be very difficult to achieve (or almost impossible) so you will need to use it 'locked'.
At those magnifications atmospheric conditions will most likely degrade your footage quality.
If you are mainly shooting birds I would go for 100-400 as the all around lens
and maybe the 70-200 for low light.
If you need it for other animals, go for the 70-200 + 1.4 TC (slr) for close up of birds or animals, I think the extender will lower the quality of your footage on both lenses. The 1.4 TC (much better quality then the extender )will give very good results with the 70-200, I would avoid using it (if posible) with the 100-400 lens.
To get better quality shots ,get the best video head that you can afford, and
Ronsrail and Ronssight http://ronsrail.com/ or the equivalent.

Sassi

I second the ronsrail suggestion. It's expensive, but seems to be quite good quality, and makes me feel a lot more confident that the lens will be properly supported. I think it has potential for use with future lens collection additions too.

oh so EF/AF doesnt work when you use the EF adaptor?
does IS work?

julz