Paul Wetton wrote:With 400mm on my canon XL2 video camera I get up to around 60x magnification
Damn! Ive gotta get me one of those video cameras. They look awesome! 60x magnification sounds like it would be good for filming the Purple Emperor and Purple Hairstreak
Gruditch wrote:I would gladly sacrifice 100mm and have the Canon 100-400.
Ive tried this one out and it really is a good lens. I decided to get the 300mm L instead because i thought the push and pull zoom might drag dust inside the lens body. Not sure if this is an issue or not.
Gruditch wrote:The 24-105 is great lens, I just wish it didn't extend when you zoom, and I wish I could remember to turn off IS when doing long exposures.

Im glad im not the only one who forgets to switch off IS when using a tripod. You get so used to using it with IS on that you forget its actually there! Will have a look at the Sigma 17-50mm, though i was hoping to replace my 10-22mm with something as wide as 12mm at least.
Pawpawsaurus wrote:The plastic body, awkward focusing, rotating front end, non-linear zoom, etc. are all irritants (which the review does indeed agree with), but they shouldn't affect the image quality per se.
The quality of the 18-55mm glass is the lowest Canon do, i reckon. That, along with the other factors, is why its a kit lens. I dont claim to know much about what makes a lens work but there are a number of factors that affect image quality. For a cheap lens, you're just not going to get high quality. Thats why ive stuck mainly with L lenses. Save up for the best you can get and you'll save money in the long run. I know someone who has bought lenses, not been happy with them and had to buy new ones. He wasted a lot of money doing it that way.
Pawpawsaurus wrote:At some point I'd like a decent general-purpose lens which would handle them reasonably, and I was hoping that the 18-55 IS would do the job, but apparently not. At the top of my current shopping list is a butterfly-friendly macro lens, which I'd like to buy soon enough to be able to practise with before the season starts.
It depends on your budget. But for general purpose, i recommend the 24-105mm L (if you're not bothered about the wide angle) or the 17-40mm L which is cheaper than the 17-55mm and can be used on any camera body. Gruditch vouches for it

I saved a lot of money buying from kerso. It would be worth getting a price list from him. Also check out Sigma, Tamron and other makes. But in my opinion, Canon are at the top of their game. For butterflies, the 100mm L IS macro is top notch. The non L 100mm is also quite good ive heard and is cheaper but lacks the IS which really helps in low light. I photograph a lot of butterflies at roost (as they are nice and cooperative!) and i would be lost without the IS. I also have the 60mm which is great but lacks the IS. As Gruditch says, i dont think theres such a thing as a bad macro lens. But IS, for me, is a must on these lenses.
Pawpawsaurus wrote:I've been advised to always shoot RAW, so I may end up using the RAW + L setting in case the camera can get things right without any help.

Anything shot in RAW, despite the L setting, will look a little soft. You need to sharpen a bit in post processing when you convert the RAW file to TIFF or JPEG. I used to swear by JPEG and hated RAW but ive come around now

I still shoot in both though. Old habits die hard!