xrays said:
Personally, based on your requirements, I'd suggest the Canon 70-300 f/4-5.6 IS USM lens. It's relatively new, covers the standard telephoto ranges you'd want for outdoor wildlife and some sports, and should run around $550US (maybe less).
These are pretty much my thoughts too; I just went through a similar "what to get" decision around a year ago, and took a Canon 20D w/ 1.4x and the EF 70-200mm f/2.8 IS on a two week long safari to Tanzania this past summer.
This combination is effectively a 98-280mm f/4 before the crop body's 1.6x, which takes it to a 35mm equivalent of 150-450mm.
FWIW, the reason I chose this combo over the 100-400 IS is because I was concerned for low light conditions and wanted to be able to drop the 1.4x to get to 200mm @ f/2.8 In reality, I was reluctant to pull the lens off in the field (dust) and our low light conditions weren't all that common: I compensated by jakcing the ISO and using a sandbag. However, since the 100-400 is f/5.6, this would have been 'one more stop' and I do think that I would have lost a couple of interesting shots...probably not that many to really cry about, though, and I would have benefitted from the increased reach more frequently IMO.
BTW, I came home with around 4500 images, so work out your digital storage plan too; for me, I realized around 35GB (shooting in JPEG+RAW) worth of digital media consumption.
Regardless of the statments about needing f/4 or lower to shoot, I think you'd be very happy with this lens, for just about any shooting situation - especially outdoors.
The lighting will be marginal at times, but not necessarily 'all that horrible', for the dSLR's are quite acceptable at ISO 400, which helps offset lens limitations, and IMO, losing 1 stop in glass while picking up IS ("worth" 2-3 stops) is generally worth the trade-off.
Generally speaking, for the game drives we went out on (Tanzania), we had a morning and an afteroon game drive. The normal daily routine was:
1. Wake before dawn, went to breakfast at right around dawn, then loaded up in the jeep around 60-90 minutes later. As such, light levels for the morning game drive weren't really a problem.
2. Cleanup, have lunch, rest, clean photo gear, "saddle up" at ~3pm; be out until sunset - sometimes earlier, sometimes later: some parks technically probibit you from being out after sunset, although from what we saw, it seems that they generally expect guides to run late, either because they stopped for animals, or because they were at a scenic overlook for the sunset. As it gets darker, crank the dSLR up to ISO 1600. If you have room (weight budget), an external strobe with a "better beemer" works pretty well.
I'll try to pick through my images this weekend to find & upload some illustrations (we also had a P&S with us and did "double-shoot" some subjects under marginal lighting).
BTW, before I forget, game drives will be dusty - put a 'skylight' or equivalent lens filter to protect your lens and take a "rocket" bulb with you - - out in the Jeep - - to be able to blow dust off the lens during the ~4 hours that you'll be in the Jeep for the game drive. The roads can get quite dust-choked at times (particularly in areas with other vehicles passing by) and your lens surface can get dusted up surprisingly fast. In one particularly dusty park, I got to the point of keeping my lens cap *ON* at most times an still took the Rocket to it every half hour or so.
The benefit of this lens over, say, the 70-200 f/4L is simply the extra zoom range and the IS option. Both of these will be invaluable for wildlife, especially considering the price range. The lens is very good, and for an amateur photographer on vacation, it will produce some very memorable images.
From a hardware perspective, I was generally surprised with how many tourists simply had a little P&S to use instead of an SLR/dSLR, although in balance, we were a bit early on season and didn't encounter any other Americans. From those that had (d)SLR's, most weren't what I'd consider to be "L" glass class, although everyone with an SLR did have at least 200mm worth of telephoto reach.
If you feel like spending the extra money, the next step up would probably be the 70-200 f/4 IS L, or the 70-200 f/2.8 L, but each of them will run near $1000.
IIRC, the former's less than $1K and the latter's closer to $1600, but in either case, pairing it with a 1.4x teleconverter to get it up to 280mm will add another $300.
Then there's also the 100-400 f/4-5.6 IS L, but it can be bulky for a casual shooter, especially on vacation.
Its not significantly heavier/bulkier than the 70-200 f/2.8 IS L, particularly with a 1.4x. When you're riding around in a jeep on a game drive, camera weight really isn't too much of an issue. Also, because subjects can be at any quadrant, I felt that I made the right decision to not take a tripod. I'm sure it makes a difference for those photographers with the huge 500mm lenses, but in their case, they're probably also paying to have a vehicle completely to themselves, so they have 'elbow room' as well as no other tourists to have to negotiate with for the best spot. I did take a Kenesis U-fill-it sandbag, but the jeeps had their own sandbag that I was able to use when I (infrequently) needed it. Probably worth taking a fill-it-there type of sandbag along, since they're relatively cheap and weightless, which then allows you to adjust on the fly based on the conditions you find.
PS> Make sure you have a polarizing filter on whatever lens you buy, because it'll make all the difference when shooting outdoors!
I'd say "make sure you bring one", but it will depend on lighting conditions as to the decision to use it or not, for a standard polarizer costs another stop.
-hh
