Sigma 70-200 f2.8 APO DG HSM II vs Canon 70-200 f4 L IS

I have looked at past threads and have read a lot about opinions regarding the canon 70-200mm f2.8 IS vs the f4 IS, but couldn't see anything comparing the sigma with the canon.

I currently have the Sigma 70-200 f2.8 APO DG HSM II which has no image stabilization and I am wondering whether it is sensible to sell it and convert to the Canon f4 with IS. I can't afford the Canon f2.8 IS at the moment so that is not an option.

Currently I use my 70-200mm at a lot of weddings so often there is low light in the church, but the camera is then on a tripod, but for candid shots during the reception I find the Sigma quite heavy and feel I would benefit from IS.

My main photography work however involves a lot of hiking and travel and I am planning on purchasing the Canon 100-400 IS so think I maybe doubling up on lenses quite a lot.

What does everyone else think? I would appreciate some ideas.

Welcome to the forum. I think you'll find the Canon 70-200/4 l IS lens very handy and vary sharp. I'd switch from the Sigma myself. But, will you need something faster and longer for your weddings? Like a 200/2.8.

Well I am wondering about that, but I do also have a 100mm f2.8 lens, so I may be able to manage with using that as my fast lens.

I had the Sigma 70-200 f2.8 APO DG HSM II and I found that I did not always bring it with me because of it's size and weight and found myself wishing I had brought it along on more than one occasion. I was very impressed with the build and image quality of the lens.
I sold the Sigma lens after about a year and bought a Canon 70-200 f/4L IS. Which I am very happy with. I bring it with me all the time. It will fit in my LowePro Slingshot AW200 while attached to my 40D.
The Canon lens is noticeably sharper than the Sigma and the IS is amazing.

Terry

Remember that 4.0 isn't 2.8. And you can't pop up your ISO forever... sometimes 2.8 is needed .