Hello,

Two months from now I will be going to India and will be spending some time in the rainforest shooting snakes, frogs, large bugs etc. at the peak of the monsoon season. I am considering taking along the Canon 200mm f2.8 L II lens w/ Canon 7D and 1.4X TC II. I plan to increase magnification by using one or more extension tubes and using a tripod with macro rail for macro work. I am looking to achieve 0.4x-0.5x magnification.

Few questions:
1. I am a bit apprehensive about using more than one tube with TC attached to this lens, am worried that the system might not be very stable because the lens does not have a tripod mount, so this will be a very front heavy setup the more tubes I add. Would like to ask the community here, will the top heaviness not be such a big issue with say 2-3 tubes (e.g. all the tubes in the Kenko set?)? Also does the order matter which one goes first, TC or tube?

2. I came across a used Canon EF25 (original version) that sells for ~$45, so half the price of Canon EF25 II so am considering purchasing this. I have looked on the internet for what the difference is between the version I and II but did not find any, does anyone know? Another route is to buy the Kenko tube set for $110 but if I'm spending $110 on tubes only maybe I'm better off buying the Tamron 90mm macro used for around $170 and use that lens for macro work and use the Canon 200mm + 1.4X for birds and flowers etc.

Appreciate any help/comments

Thank you
Nikhil