>> I plan to sell my Sigma 15-30 and get a Canon prime wide-angle lens (20 or 24mm) instead.
1. Why do you plan to sell the 15-30?
Largely because of its slow autofocus and bulkiness. I rather cover wide-angle with a smaller lens.
2. 20mm and 24mm have VERY different FoV's. The two complement each other, not replace.
3. Which 24mm prime, 24/1.4 or 24/2.8?
4. You will have 24mm in your 24-105. Why consider another 24mm prime?
Correct on all counts. Good points.
5. The 20/2.8, despite being a prime, does not have the same quality consensus as almost all other primes.
6. Have you considered the 17-40/4?
No, I haven't but I will. Thanks for the suggestion.
>> I plan on keeping my 70-200/f4.
>> I'll keep my 28mm, my 50/1.4, my 100-400 L IS and my 1.4 converter.
1. Why keep both 70-200/4 and 100-400 IS?
Because the 100-400 is very large and a lens I only take with me if I know for sure I'm going to use it. The 70-200 is much smaller and can always sit in my camerabag.
2. Why keep the 28/2.8 when you will have it in the 24-105?
Largely because it's small and because I'll also keep my 10d for personal stuff, on which the 28mm is close to a normal lens.
>> I'm considering the 70-300 DO, but it duplicates other lenses.
I agree but it seems you will have other duplicates as well.
Some general questions:
1. What is your budget?
2. How much weight are you willing to carry?
3. Will the 5D be your only body?
4. Why not buy the 24-105, sell nothing, and only then see if and what you are not using any lens?
1. I'm flexible.
2. Much of the shooting will be done close to the car, while for trips weight becomes a problem, which is why the DO is so appealing.
3. I have a 10D, which I keep, but I'm not sure whether it produces a good enough image for stock. I have a 1D, which I was planning to sell.
4. Because I'm leaving the US in the summer and can buy lenses now at much lower prices than I can when I'm in Europe.
Thanks for your reply.