Help deciding on zoom

I'm having a lot of difficulty deciding between the following zooms:

Canon 70-200 f4L

Advantages:

- Light
- Sharp
- Excellent build quality
- Inexpensive (half the price of my other choices)

Disadvantages:

- Slow

Canon 70-200 f2.8L

Advantages:

- Sharp
- Excellent build quality
- Fast

Disadvantages:

- Expensive
- Heavy
- Big

Canon 70-300 f4.5-5.6 DO IS

Advantages:

- Longer reach (nice to have ... not a must)
- Compact
- Almost as light as the 70-200 f4
- Not quite as sharp as the L lenses, but darn close
- IS

Disadvantages:

- Expensive
- Really slow
- Not sure if the build quality is as good as the L's ... but probably good enough

So, if I want to shoot indoors I think the f2.8 would be a good choice ... but what if I shoot indoors with my 420EX, or if I invested in a more powerful flash? I'm not shooting sports ... more school concerts, etc.

Outdoors these all seem to be great picks, with the DO having the advantage of being more compact and having longer reach. However, I really don't have a lot of need to go past 300 (more of a nice to have), so really I'm only comparing these lenses for their usefulness up to 200mm.

Anyone else go through this excercise? Any opinions would be great.

Bob

if budget not a problem - fast lens of 2.8 and L quality
what do you intend to use the lens on?

Mainly outdoors, scenery, kids outdoor sports, etc. Indoors would be more for concerts, etc where flash is allowed.

sorry i meant camera body

Ah! I have a 20D.

well on the 20D you have a Field of View factor of 1.6 so the effective focal length will be
so 70-200 = 112-320mm
hopefully other people who have the lens may post some examples for you.
for concerts the F2.8 may be useful
but you may want to try on camera body and how they feel to you

Because of the crop factor I really feel that 200 will be long enough. And 70 is great since it matches with my 24-70 f2.8L.

Bob, if you can forget that you spent what it costs (as opposed to soothing the wound from the rolling pin), the f2.8 IS is a lens that you will forever treasure. Every time I grab mine I'm very glad that I made the choice to get it.

It's a little heavy, to be sure, but that really aids in using it too. It gives it some mass to keep it steadier. Couple that with the IS, and it's really a dream to use hand-held. The only time I don't like to use it handheld is when I'm sitting out waiting for birds to come by. Then I put a monopod under the lens's tripod mount.

I, too, have the 24-70mm f2.8. At the short end of the spectrum the 16-35mm f2.8 is the perfect third member of the trio.

Thanks Skip.

The 70-200 f2.8L IS would be a great choice, but it is quite a bit more than I'm willing to spend at this time. So, given this, would you pick the 70-200 f2.8L over the f4L if you were only using it indoors with flash?

The Sigma 70-200 f2.8 is a more practical lens for what you want. I have owned it and the Canon f4 and definately would prefer the SIgma. Doesn't cost much more.

Agree that the Sigma is probably a decent choice, however since I'll probably be purchasing on-line I'm a bit concerned about several comments I've seen regarding quality control for Sigma and Tamron lenses (good copy syndrome). For this purchase I've narrowed it down to the three lenses I listed in the Canon family.

That DO lens is not slow when you take into account that the new gen IS gives 3 stops at low light hand holding! Yes it is not cheap, but its in a class of its own and you get 100 more mm.

I think if I were trying to make this decision, I would look at the flash unit(s) that are part of the equation as well as the expected distances to the subjects. Then I'd figure out what f-stop setting(s) I would need for the flash. If everything calculates out to above f4.0, then the less expensive of the two lenses should work fine. If you need more light-gathering capability, then go for the f2.8 lens. If you need even more light-gathering capability, scrap the zoom idea and go for a couple of fast primes.

Good advice Skip.

Looking at the exif data from the last school concert I took photos at, I used ISO 400 to 800 at f3.2, using my 420EX about 50 feet away. Note, the ISO 800 photos were useable, but I would have preferred to not shoot these particular scenes above ISO 400. I believe that I was running out of flash power at ISO 400 because I used a Lumiquest mini-softbox on the flash, and sometimes used high speed sync (1/320s). With the diffuser off and normal sync I would have had barely enough power at ISO 400 to shoot at f5.6, and may have been able to shoot at ISO 200 at f4.

My 420EX is capable of:

68.9 ft at ISO 400 and f4
49.2 ft at ISO 400 and f5.6

48.7 ft at ISO 200 and f4
34.8 ft at ISO 200 and f5.6

So, for the types of shots I would use the lens for indoors, the DO wouldn't be fast enough using my 420EX, and the 70-200 f4 just works. For the 580EX I calculate the following:

95.1 ft at ISO 400 and f4
68 ft at ISO 400 and f5.6

67.3 ft at ISO 200 and f4
48.1 ft at ISO 200 and f5.6

With the 580EX, both lenses would work, but the f4 is clearly more flexible.

Thanks again for the advice. This has conviced me that my choice should be between the 70-200 f4L and the 70-200 f2.8L. The DO is a sweet lens though, just wish it were a contiuous f4 and my order would have been placed

If you have the money:
EF 70-200mm f/2.8L IS USM

A Fantastic Lens!!!!!