General purpose lens - Canon 18-135mm or Sigma 18-200mm

Vanilla · 8 Jul 2011 at 02:31

Like many novice users i'm looking for one general purpose lens. I'm not a big cropper but would like better zoom than my Canon 18-55mm provides.

I'm considering the Sigma 18-200mm OS lens - cheaper than the Canon and seems very good.

However, today I was playing with a friends canon 18-135mm and Canon 18-200mm and it looked like the max zoom on the 18-135mm was almost as good as the 18-200mm! Although I was indoors the additional zoom on the 200mm seemed almost negligable! Has anyone else ntoiced this?

The Canon 18-135mm is a bit cheaper than the Sigma lens.

What would you advise? Stick witht he Sigma or go for the smaller, lighter Canon?

Current Kit:

Canon 500D
50mm 1.8
18-55mm IS (kit lens)

Update: Now looking at the Tamron 18-270mm PZD. Can you tell I can't make my mind up?

Myocardial Inf · 8 Jul 2011 at 11:35

What's you budget, I'm presuming about £300 max? Does that include selling the 18-55?

If it was me rather than buy a lens that was going to overlap what I already had I'd been looking at something like the canon 70-200 F4L USM, little bit more than the 18-135 but a better lens overall.

Chiz · 8 Jul 2011 at 12:04

I have the sigma and I use it as my everyday, all purpose lens.

It's a good lens, a very good lens, especially for the price. The only gripe I have is when full extended, the focus is no where near as sharp as it should be on close objects. If it's extended and you're trying to focus on objects that are afar, then it's fine.

This is the only fault on what I find to be a relatively inexpensive and fully functional lens.

matty_1210 · 8 Jul 2011 at 12:40

which one is better signa or canon as i was thinking of getting a 18-135mm lens?

D.P. · 8 Jul 2011 at 13:27

Vanilla said:
Like many novice users i'm looking for one general purpose lens. I'm not a big cropper but would like better zoom than my Canon 18-55mm provides.

I'm considering the Sigma 18-200mm OS lens - cheaper than the Canon and seems very good.

However, today I was playing with a friends canon 18-135mm and Canon 18-200mm and it looked like the max zoom on the 18-135mm was almost as good as the 18-200mm! Although I was indoors the additional zoom on the 200mm seemed almost negligable! Has anyone else ntoiced this?

The Canon 18-135mm is a bit cheaper than the Sigma lens.

What would you advise? Stick witht he Sigma or go for the smaller, lighter Canon?

Current Kit:

Canon 500D
50mm 1.8
18-55mm IS (kit lens)

Update: Now looking at the Tamron 18-270mm PZD. Can you tell I can't make my mind up?

With all these 18-200 type lenses there is a very severe focus breathing and also a fairly exaggerated maximum focal length. Typically there are more like 185-190mm at max focal length at infinity focus. When you focus closer the effective focal length reduces down to more like 120-135mm.

A lens I would consider is the Canon 15-85mm. It is always much more benefitial to be able to wider than to get a little closer with a lens. You can always crop or move closer to a subject, but you can make a photo have a wider FoV or backup through a wall and making a sweeping vista wider may mean having to back up 100km in a helicopter which is hardly practical.
The difference in focal length between 85mm and 135mm is really quiet small, the difference between 15mm and 18mm is huge and has a far larger impact on the photos than a small amount of extra reach which can be achieved by cropping or walking forwards.