n0b0 wrote:
Ah yes, you're right, I missed that. The purple CA seem to get stronger as it gets closer towards the edge doesn't it?

Yep, that's normal.

Hmmm... I might pass on these 11x extreme zoom lenses for a multi purpose lens as the IQ seem to suffer quite a bit from various little problems.

A slight spin to an old saying, I'd say if an image is worth taking, it's worth taking well... at least as well as your skill and wallet allows.

The 18-200 will serve a purpose in the market place. I use a 28-135 allot for casual shooting because it's kind of ready for anything keeping me from carrying or swapping between several lenses.
We have all heard the "walk around lens" phrase. A decent 18-200 would qualify, you think?

therock wrote:
We have all heard the "walk around lens" phrase. A decent 18-200 would qualify, you think?
Yes it does qualify but the problem is there doesn't seem to be one that is at least above average if not great. I saw some test results for the Sigma 18-200mm as well as Tamron 18-200mm but they all seem to be average at best. I don't know, maybe I'm spoilt by the excellent sharpness of the cheap 50mm f/1.8 and 100mm f/2.8 macro.

http://www.cameralabs.com/reviews/Sigma18200mm/

I thought perhaps a shorter range of focal length would give some of the quality back but Sigma 18-125mm seem to have pretty bad reviews as well here. If only Canon 24-105mm L would have a bit more on the wideangle side... I wouldn't hesitate to get a 17-105mm L lens at all, that'd be the perfect walk around lens.

n0b0 wrote:
therock wrote:
We have all heard the "walk around lens" phrase. A decent 18-200 would qualify, you think?
Yes it does qualify but the problem is there doesn't seem to be one that is at least above average if not great. I saw some test results for the Sigma 18-200mm as well as Tamron 18-200mm but they all seem to be average at best. I don't know, maybe I'm spoilt by the excellent sharpness of the cheap 50mm f/1.8 and 100mm f/2.8 macro.

http://www.cameralabs.com/reviews/Sigma18200mm/

I thought perhaps a shorter range of focal length would give some of the quality back but Sigma 18-125mm seem to have pretty bad reviews as well here. If only Canon 24-105mm L would have a bit more on the wideangle side... I wouldn't hesitate to get a 17-105mm L lens at all, that'd be the perfect walk around lens.

1) What is a good walk-around lens? Is it a matter of focal length, subjects and/or convenience?

2) A zoom lens represents one big compromise between IQ and convenience. There are no superzooms that have excellent IQ all over the zoom range.

3) What is excellent IQ anyway? This is highly dependent on the output... Also, a lot can be straigthened out in PP. For 50x70cm prints you will want a very good lens for sure. But for vacation snapshots, the 18-200mm should be able to deliver good looking 20x30cm prints (after some careful PP). And most vacation snapshots will be printed even smaller.

Well for me the most important factor is how sharp it is. As I mentioned in previous page, CA and vignetting isn't hard to fix but there's a limit to how much you can sharpen a soft image.

I suppose it's not in any lens manufacturers' best interest to create an excellent multi purpose lens as it would probably render half of their products obsolete.

Thanks for taking the time to post these.

I owned the Sigma 18-200 OS for a while on my 40D and I can say the best thing about that lens was it was very sharp at 18mm and 200mm at almost all f-stops. It was much better than these samples seem to indicate the Canon is. The problem with the Sigma was in-between the extremes - at several points in the middle of the zoom range, the edges were really bad, though the center was usually quite good. I also had focusing issues with the lens on my 40D so ultimately sold it and got a Canon 24-105 F4. I should also say the OS on the Sigma was great.

Anyway, I had high hopes for the Canon 18-200 IS based on the new 18-55 IS and 55-250 IS lenses, but must say based on these tests, it doesn't seem to stack up.

I beg to differ. There is a great super zoom. The Leica 14-150 (28-300mm in 35mm terms). Yes it is pricey, but there is a reason. It has no compare in the superzoom world. Im awaiting the delivery of my 50D 18-200 kit.

Tommy

Daan B wrote:
Besides that, the center of the frame seems sharp, but sharpness degrades very fast when you move away from the center. In the extreme corners it is very soft (both at 18mm and 200mm).

If it is sharp in the middle range (in corners), then it behaves exactly at the opposite way as the Sigma 18-200 behaves. 18 and 200mm are sharp, even in the corners, and even wide open but e.g. at 35mm you need to stop to f8 to get the corners bearable and f11 to get the OK.

The Sigma 18-200 actually beats the 70-200f2.8L IS to pulp when it comes to the 70-200 MFD (which is not the MFD to the 18-200, btw), wide open.

It looks to me like youre maybe getting 5MP out of your 15MP camera with that lens. Understand that 15MP on a 1.6x crop is putting enormous stress on the optics and without a super sharp lens you are simply not going to take advantage of all that sensor has to offer. Expect this situation to get worse in the future when Canon crams more and more pixels onto the same sensor sizes.

In actuality, 5MP is enough for most people's casual uses so I dont think it'll be a huge concern.

Thank you Kenshin for the time and care in posting this. Its helpful people like you that make this site work.
Your timing was great - I just got B&H's notification that the 50Ds were in stock. With your input, I decided against the kit with this lens. Your first impressions confirmed what I would guess about it.
I had the Canon 28-135 for many years and the vignetting and distortion bugged me the whole time. I know now its fixable in pp, but I like to carry more lenses now and do less work later. Great shots, BTW, they illustrate the range and limits well.
Hope you do get good use out of the new lens. If you'll share your insights after using it for some time, I for one would be grateful.

I did a bit more research and found the Tamron 18-250mm (not the older 18-200mm). It seems to have pretty good reviews. Perhaps slightly lower IQ than that 14-150mm 4/3 lens that Tom Molnar mentioned but the price is also 1/3 of that.

n0b0,

I was just pointing out that someone said there is no quality superzoom. The Leica is at the top of its class... but you gotta pay to play.

I have the Leica 14-150, and use it on my Olympus E-420. It's a superb super-zoom.

I also have the Canon 18-200IS on order - looking forward to seeing how it compares.

Mike

Hey Kenshin, I hate you - for posting this! now I have to apply for a bailout from
US government to get the money for more gears!!!

I am not sure whether IQ is quite good, due to the new 5D-MK2's sensor or from just the lens itself. Perhaps, if you can shoot the lens with 30D/40D. I bet others might jump into the band wagon if the IQ is still or almost 95% the same. For traveler and fine arts photographer like myself, which I mostly convert picture into painting, which don't required the best IQ, but if as good as 17-40mm (or 17-55mm) then 18-200mm will be in my bag someday - soon. Thanks


I suppose it's not in any lens manufacturers' best interest to create an excellent multi purpose lens as it would probably render half of their products obsolete - NoBo
Was it what they called "shoot oneself in da foot?"

Tom Molnar wrote:
n0b0,

I was just pointing out that someone said there is no quality superzoom. The Leica is at the top of its class... but you gotta pay to play.

I realise that Tom, but since that Leica is in the same class as a Canon L lens price wise, I was trying to find the best compromise between quality and price. If this Tamron is as good as the reviews said, it could be the lens with the best performance per dollar value you can get.

I would love to see a shootout between the Tamron and that Leica.

Ok gotcha n0b0. No worries.

Tommy

I have an Olympus E-420 and bought the Panasonic/Leica 14-150. It was very inferior to the Zuiko 14-54; perhaps I simply got a "bad copy," but I don't think B&H would be ready to order another (and another, etc.) till I was happy with one. The stabilization worked as advertised, but the colors were flat and it didn't resolve much detail. Glad you got a good one; wish I had.

I don't imagine anyone was expecting *too* much from the all-in-wonder glass tho..

jeremy_clay wrote:
I don't imagine anyone was expecting *too* much from the all-in-wonder glass tho..

Strangely enough, the 36-420mm 12x superzoom in Canon S3 IS is actually quite good, even wide open (f2.7 to f3.5!) and throughout the range, even in the corners.

I bought one for my kids but also run it through some tests. The image quality is comparable to the better DSLR consumer zooms with a range around 3x. Though, don't ask about high ISO image quality - there is none.

I've been shooting with the Canon 18-200IS for a couple of days now (on my 50D body).

Initial impressions: the lens is best on the long end (200mm), and weak on the short end (18mm).

At 200mm, I'm quite impressed with the sharpness, contrast, etc. The look at 200mm reminds me of the 70-300 f4-5.6 IS lens.

At 18mm, the lens is softer, and shows distortion and CA. It's usable, but there's a big difference between this lens at 18mm, and the Canon EF-S 10-22 at 18mm.

As a superzoom, for walk-around convenience in a small package, the lens offers a decent set of trade-offs, and I'll make use of it. But I won't be shooting any serious wide-angle landscapes with it.

Mike