The Canon EOS and Photography Forums

Hi,
Am going on a wildlife trip.I've got the Canon 7D with the Canon70-300 USM IS lens.I'm sure I will wish that I had more "reach" while on my trip. I thought I could simply buy a convertor but I've found out that its not as easy as that. I'm considering buying a Canon 100-400L lens but its such a lot of money. Any suggestions? I've also looked at the Sigma 15--500.

What kind of wildlife? If you're talking bear, elk, bison and the like you may find 300 is enough, especially on a 7D. If you mean birds, coyotes or other small mammals then you're probably right. Have you considered the 80-400 Sigma. It has image stabilization.

If you think the EF 70-300IS (http://www.amazon.com/exec/obidos/ASIN/B0007Y794O/bobatkinsphotogr) is too short and the EF 100-400IS (http://www.amazon.com/exec/obidos/ASIN/B00007GQLS/bobatkinsphotogr) is too expensive, I'd say that your best bet is probably to take a close look at the Sigma 150-500OS (http://www.amazon.com/exec/obidos/ASIN/B001542X6E/bobatkinsphotogr). It has  longer reach then the 70-300, it's cheaper then the 100-400 and it has image stabilization. You can get it from Amazon for $999 (with free shipping).

I tested the similar Sigma 50-500OS (http://www.amazon.com/exec/obidos/ASIN/B003A6H2Y8/bobatkinsphotogr) recently and found it to be pretty good (though it's more expensive then the 100-400IS, so that probably rules it out for you). For wildlife work you probbaly don't need the 50-150 range (plus you already have it covered anyway).

Otherwise there really aren't any good ways to get significantly more reach than your 70-300 will give you and keep the cost under $1000 and the optical quality high. These days nobody makes a 400/5.6 for Canon except for Canon(!) and though it's small, light, fast focusing and very sharp, they still haven't put IS in it and the price is still over $1000 (Canon EF 400/5.6L (http://www.amazon.com/exec/obidos/ASIN/B00009USW3/bobatkinsphotogr)). There are some cheap 500mm mirror lenses, but they are slow, fixed aperture, manual focus, lack stabilization and are not always very sharp, plus they create "messy" out of focus backgrounds. They are cheap though! (Opteks 500/6.3 mirror lens (http://www.amazon.com/exec/obidos/ASIN/B0022VFDRK/bobatkinsphotogr)}

I am using the Sigma 120-300/2.8 with 1.4 or 2x.

I don't like my Canon 400/2.8 or the 600/4.0. They very limited.

I rather have & use the Sigma 200-500/2.8.
But it's heavy. 
When I carry this monster into stadiums, they never ask me for ID.

PS:  Sigma will not support you if you need parts.  I couldn't get a hood from them.
Canon hood is over $600.00.

If buying the 100-400 is too expensive, why not rent a lens? There are many reputable lens rental facilities. Some will even deliver to your door. This way you can try out any lens before you plunk down your hard earned coin. Just a thought.