Lens recommendation? Taking a trip to California national parks.... Please Help

[fokker]

Get the 24-105. You'll want the longer zoom for many many things. You'll find it comes up short for a lot of stuff.
If I were making the choice I'd go with the 24-70 f/2.8 and the 70-200 f/2.8 and probably a 7D to give that extra little bit of multiplier. Not to mention the focus system issues with the 5d2. If you REALLY needed to go to 18mm you could use your kit lens on the 7D as well.
The Sigma 70-200 f/2.8 OS is a great option if you are trying to save a few bucks as is the Sigma 24-70 and the Tamron 17-50 or 28-75.

Really? Unless he's shooting sports or fast moving animals (not likely at 40mm or 105mm) I can't see what the problem is here. The 5d isn't that bad at autofocus, I've shot a few sports here and there with mine and honestly have no complaints at all. For landscapes autofocus is basically useless anyway.

 

[hxdrummerxc]

Wow thanks for all the input so far everyone......
Im for sure going with the 24-105mm,

@MLeeK,
You made those pictures look great for 12800. With my XSi, I try as hard as I can not to even use 1600. And when I do, I usually end up doing some noise reducing on it.

@Fokker
That's my thinking too, the AF may not be as good as the 7D, but im used to something far worse than either of them. And im doing mostly landscapes and portraits, and I tend to use a lot of Manual focus.

I still can't decide between 7D and 5DmkII. Don't get me wrong, I totally trust MLeeK's opinion.... Its just that I plan on buying a 5DmkII (or another full frame) sometime in the near future (hopefully within the next year). And I kind of want to feel what a full frame feels like, and use one to see if its what I really want. This might be the perfect opportunity for me to try a full frame out.

 

[MLeeK]

I do noise reduce in raw processing. Settings range somewhere around 30 for luminant noise and 20 for color noise. I believe adobe's default is 25 for color-which is OUTRAGEOUS on the average image.
You can use your XSi at 1600-if you learn how to expose for high ISO!!!! I used the XTi successfully at ISO 1600 and it had a lot more noise issue than yours does!!!

 

[bromic10]

I'll would have no dubte. My choice is 24-105. 24 is a good wide angle when you are shotting wiht a full frame camera and you are going to agree to be able to use a 105 and no to be stopped at 40. Besides, full frame allows you to crop images with your software, keeping a high quality; this is going to be something similar as shotting with a longer zoom. An other thing, if anywhere you need a shorter wide angle you have the possibility of taking 2 or 3 shoots and mix them as a panoramic image. When I do this i shoot in portrait position, because distorsions of wide angle don't affect the mixing area. I guess you to visit my blog where you would see many photos taken with this kind of zoom. Apologise me because of my written mistakes, my english level isn't very good and my iPad doesn't help me because it's trying to translate it to my language at any time. I hope to be helpful.My blog is http://www.carlesporta-fotograf.blogspot.com