My First Lens Upgrade Project

I've had my Canon 450D for about a year now, and my lens array almost as long. At present, my kit contains:

• EF 50mm f/1.8 II aka 'nifty fifty'. The only lens I'm happy with.
• EF-S 18-55mm f/3.5-5.6. This lens is okay, but annoys me sometimes.
• EF 55-200mm f/4.5-5.6 II USM. This lens is increasingly really annoying.

Also, I've got some big events coming up (trips to Seattle and Florence, also the Olympic fencing), and I really don't want to miss out on those shots of a lifetime. 

Considerations are that I would like to stick with the Canon system - yes, the grips etc are too big, but no current full frame cameras are meant for children-size hands anyhow. I'd like to upgrade in future to something like the Canon 5D mk III. Not this year, probably not next year ... but sometime. This, however, means that I need to primarily consider EF mount lenses, rather than the cheaper EF-S mount, unless I feel like replacing glass when I upgrade.

So why am I finding my current kit irritating and limiting?

Well, between tiny hands, not so awesome muscles, and various other things, there's quite a lot of shake when I try and take pictures at 100+mm, or in low light conditions. This means I seriously need to consider image stabilisation in my lenses. I lose a lot of otherwise awesome shots because I simply can't hold the camera still enough. Yes, a tripod would help with this. I do need a monopod or full size tripod one day. At this point, however, I think a new lens or two is probably cheaper and more flexible, although I am researching tripods on the side, as it were.

The upshot is I've been reading a lot of bewildering information about various lenses available for my camera. And it truly is bewildering - between poor site design, ambiguous google results, and my profound lack of knowledge, I've been feeling a little overwhelmed.

Most advice articles say something like "when upgrading, consider what you use lenses for" with the goal of pinning down which focal range you use most. Looking at my photos, I tend to take pictures of very small things and things very far away. I would like a macro lens, but that would be in addition to the current range of things I can do. Talking to another member of the London Photography Meetup Group on our Kew Gardens walk, he said "Well, you're kind of between a rock and a hard place then, aren't you?" which I believe is an accurate summation of my dilemma.

I use pretty much everything in my current range from 18mm through to 200mm, and keep wanting more at both ends. Oh, and smaller f-stop numbers. And a pony while I'm at it.

Ponies aside, I can't afford L lenses (Canon's pro lens range), so I'm going to have to compromise somewhere.

I've been using dpreview to read up on lenses, suggested to me by ... someone. It's got a nice interface for presenting only the lenses I'm interested in.

Thinking about my current issues (and budget limitations) I think it's more important for me to upgrade the telephoto lens than the zoom lens. I walk around with the zoom lens more, and take more shots with it ... but that's partially because my success rate is significantly higher. With this in mind, I've narrowed down on a few candidate lenses. Prices are from a google search, amazon.co.uk price included as a baseline retail price.

Canon EF 70-300mm f/4-5.6 IS USM. This is one chunky lens. Someone had one at the Kew Gardens walk, and let me play with it a bit. It's really quite nice to use, and I think the extra range would be something I'd very quickly become addicted to. However, it is large. And heavy. £300 or so, £420 from amazon.

Canon EF 70-300mm f/4.5-5.6 DO IS USM. Those two extra letters mean that it's a lot lighter, smaller, and more expensive. Also reviews seem to indicate it sucks.  £840 and up, £1103 from amazon.

Tamron SP 70-300mm f/4-5.6 Di VC USD. This lens gets good reviews, and has lots of technical acronyms in the name. From what I can tell, it's basically equivalent to the Canon, perhaps with better build quality. On the other hand, I haven't heard of this brand before, not that I'm overly educated in the field. £225 and up, £319.27 from amazon.

Sigma 70-300mm F4-5.6 DG OS. No reviews on my chosen review site, but a bit further afield gets me a couple of articles. It seems to be an okay lens, nothing special, but annoying if you want to use polarised filters. Affordable at £176, and £286 from amazon.

Sigma 120-300mm F2.8 EX DG OS HSM. Again, very good reviews, and lots of fancy letters. The major problem with this lens is the gap in range it leaves me, as explained below. But ... that f value is really, really, really shiny. And HUGE. And horrifically expensive. £1441, £1991 on amazon. Although there seems to be another model at £999 ish. Still too expensive.

All these lenses have something in common: they leave me without the zoom range from 55mm to 70mm (or 120mm in the case of the expensive Sigma). 55-70mm isn't too large a gap, and isn't a range I use much anyway. On the other hand, 55-120mm is quite a large gap, which covers quite a lot of range I do use. It's a wishlist lens anyway.

I know I need to get myself to a brick-and-mortar and play around with the various lenses to see what I can do with them, and whether I actually like the way they go. Still, it looks as though I'll be shelling out around £200-350, depending on which lens I go for and from whom I purchase. Of course, these are also all new lens prices; I've yet to investigate secondhand prices, which is of course the next step. Along with finding reputable sellers in the UK. Then again, I'm really tempted by having a lens with a warranty. Also, I probably need to get a UV filter and hood for whatever it is I get.

Is there anything I haven't considered? Have I missed a really good candidate? Got tips for where to buy (and try) any of these in London?