SuperZoom lens. Which one to get

[SpinnignCone]

Ive been poking around with my new XSi and am liking it but need a new lens. the 18-55 kit is pretty good but i bought my camera mostly for an upcoming trip and i need a wider range .

First i know you get better pictures overall switching between wide and tele lenses but for now the convenience of one travel lens outweighs all that. perhaps later i'll invest in separate lenses for now i need one that can do it all.

Ive pretty much narrowed down the field to the cannon 18-200mm and the Tamron 18-270mm

ive looked at tons of reviews which flop flop in their "conclusions" depending on who you read. the tamron looks like it has better sharpness and edge to edge up to 200 mm. where it still better edge to edge but its overall sharpness is whipped by the canons. Tamron is much better in the CA department and has the extra 70mm

the Tamron IS is a bit less capable and its a stop slower on the tele side. both are about the same price.

http://www.cameralabs.com/reviews/Ca...S_18-200mm_IS/ has a great review with direct comparison of the 18-200mm to the kit lens with center and edge crops but they dont have the tamron lens

http://www.slrgear.com/reviews/showp...ct/1219/cat/11 has some good data too but while their blur rateing thing is close to dpreviews one it seems to favor the canon overal

http://www.photoreview.com.au/Canon/...6-is-lens.aspx has some nice charts for both and show a much more extreme disparity between the center and edge sharpnes in the canon however the graph on the side goes up to 2800 with its lowest averages roun 2000

the Tamron chart http://www.photoreview.com.au/review...c-ld-lens.aspx shows much better edge to edge but the only goes up to bout 1900. im nut sure if that means its good edge to edge but overall the cannon is more sharp? if its an abolute sharpness it would indicate taht the far coreners of the canon are more sharp then the center of Tamron (and way sharper in the center)

overall I just can't seem to decide which one would be the best to get does anyone have expereience with both these lenses or know of a review sith a direct comparison like that on the Camera Labs site ?

[Colin Southern]

Sadly, what I have learned over the years is that if you read all the reviews for something like this you end up going nuts.

Case in point - most photographers seem to give a lot of consideration to sharpness when reading reviews, and yet correct sharpening can account for 5 times the native difference in sharpness between "lens A" and "lens B" - and yet most photographers don't sharpen their images anywhere near optimally - which just doesn't make sense to me (often they will spend $2900 on a camera and lens, but won't spent 1% of that on a book that helps them get the most out of it).

It's a bit like a the irony in something a park ranger once said - apparantly he overheard two profusely overweight men agruing over who's camera was better on the basis of the lighter one being easier to carry on tramps.

I usually suggest when going through reviews, make a list of what's important, but rather than "give a tick to model A" because it's sharper, review some shots from both and consider putting a tick in the "more than adequate" column for both, unless you're doing exceptionally large prints professionally. Another good example is say, an 8MP camera -v- a 10mp camera ... if you're only ever making 6 x 4" prints, there's absolutely no difference between them what-so-ever - same goes for lenses.

[Dave Humphries]

Hi Spinningcone,

Colin makes some very valid points (as usual).

But to answer your question about 'is the edge Canon sharpness higher than the Tamron centre sharpness'; it wouldn't surprise me at all, although I haven't been able to confirm this by checking the sites above. (Dunno why, but my ADSL (internet) is very, very slow this morning)

Here's my experience;
Back in my 35mm film days (using a lowly but capable Nikon EM), I bought a budget 38 - 100 zoom when they were just coming out. Because I liked the versatility it offered, however, after a while, I just stuck the Nikon 50mm prime back on the camera and left it there. The quality was SO much better that if I needed the 100mm end (or beyond), I just cropped more when enlarging to print (I did it all myself in those days, so I could). If I needed the WA end, well 38mm isn't THAT much different from 50mm, so I walked backwards. Not to mention the 3 stop advantage on speed. OK, so this example is also an argument for prime vs zoom in addition to brand A vs brand B, but you get the idea.

The above isn't intended to put you off a superzoom lens; having a superzoom 'bridge' camera, I will undoubtedly go that way myself when/if I ever get a proper SLR. But, especially if you might do more than 6 x 4 prints, £ for £ (or $ for $) I'd veer toward a named brand unless review conclusions* suggest otherwise (even Canon or Nikon have their duds I gather).

* although beware, some of these don't apply as much common sense as you have demonstrated already

But to end; I cannot emphasize enough how much you should listen to Colin's reasoning and advice.

Regards,

[crisscross]

Hi there

the whole point of having a DSLR is that you can and do change lenses for each particular speciality.

The Canon 18-55 is not at all bad & although you may replace it later, there seems absolutely no point in overlapping it with another lens of the same quality, suggest instead you should be looking at 70-300, the small gap 55-70 is rarely going to be critical.

The advice I was given, & think sound in retrospect, is that if you buy cheap(ish) lenses, you just pay twice as you get nowt back and pay for the good one later anyway.

If you sign up on free trial to pbase you can search by lens, identify folks achieving your type of ambition and ask them about the lens(es)

[Colin Southern]

The other thing you might like to consider is Canon's EF Lens Work III - 10th Edition (aka "The Eyes of EOS") - it gives a complete breakdown of all the current Canon lenses - MTF charts - sample photos - specifications - and also a LOT of insight into manufacturing process and other technologies such as lens communication / ultra-sonic motors / Diffractive Optics etc,

You can think of it as an encyclopaedia of Canon lenes - every serious Canon shooter should have a copy on their bookshelf.

Relatively inexpensive - got mine for $50 NZ - about $25 US (New).

[SpinnignCone]

Hi there

the whole point of having a DSLR is that you can and do change lenses for each particular speciality.

The Canon 18-55 is not at all bad & although you may replace it later, there seems absolutely no point in overlapping it with another lens of the same quality, suggest instead you should be looking at 70-300, the small gap 55-70 is rarely going to be critical.

The advice I was given, & think sound in retrospect, is that if you buy cheap(ish) lenses, you just pay twice as you get nowt back and pay for the good one later anyway.

If you sign up on free trial to pbase you can search by lens, identify folks achieving your type of ambition and ask them about the lens(es)

while the Kit lens has pretty good quality there are situations when changing lenses is not practical as well as carrying round the extra lenses. for now the superzooms should have better quality than my S5 and the slr give me better range and far less noise

later if photography looks to be something ill get into ill diversify my lens portfolio and do more "out shooting" excursions where switching lenses and carrying a tripod are the point of the outing. (likely ill get the EF-s 55-250 which seems ot have very good quality for its price but a cheap build)

For now i think ill ge the Tamron overall it seems to be the better choice, it performs better than the cannon in general and is the same price. one good review i found was at http://www.pbase.com/lightrules/superzoomtest which did have direct comparisons , the real fun was the shots comparing the 18-270 to the 70-200 2.8 L , the L stomps the super zooms in edge to edge , tho center sharpness is bout the same. even more fun was the 300 prime which in turn makes the 70-200 look bad. tho for 8.5X11 prints the difference is much less pronounced i probably wont print anything larger than that unless its stitched

anyway it should work for my needs now and if i get the hang of switching lenses or picking the right one for the right situation then you might see my lens on ebay later ;-)

[William W]

I have used the Canon lens, not the Tamron. I have seen results of the Tamron, personally I did not like it t full zoom at 5” x 7” prints.

There are a few head to head reviews in Photography Mags with these two lenses. I have read a couple. I don't place much emphasis on them. Who was paid or given what?

Sticking to the precise nature of your post and making a choice between the two, I would opt for the Canon over the Tamron - the IS, the function, less range (x11) and similarities with your existing lens and the extra stop of speed outweigh the Tamron’s extra reach (x15), IMO


***

But both are consumer lenses, where the money has been put to designing to be a one lens fits all jobs, the Canon has IS (Image Stabilization), the Tamron has more reach and VC (Vibration Control). IMO both are designed with a FL range at the expense of all over, general quality. This is not a demeaning comment, just a reality: one of the leverages of an interchangeable lens system is to have lenses to interchange when needed - as Crisscross wrote.

If you want an inexpensive EF-S lens, do yourself a favour and try the EF-S 55 to 250 F4 to F5.6IS.

It is half the price of the EF-S18 to 200 you are considering. But do not let that price difference fool you on this occasion. IMO the 55 to 250 is a little “sleeper”. The money did not go into getting the lens to work to 18mm, it stops at 55mm. 55mm to 250mm, (x5) is quite easy to design by comparison to lenses designed for x11 and x15: we have to think of where the (design) money is going.

As well as the valid point already made about FL overlapping, frankly at the consumer end of the market 18mm to 200mm (or 18mm to 270mm) is just too much FL compass to expect from a budget lens and for it to retain good IQ at both ends of the zoom range. BUT that might be leverage if you do not want to change lenses – in which case I would ask why not consider the value of buying something like a Canon Powershot G10 or Powershot SX1 IS for your trip – there are the same money as the two lenses, and IMO both (in different ways) represent a more flexible tool for a trip away and a better long term addition to a camera kit than a on fit all zoom lens to the DSLR lens set.

***

If you do want to spend more money, (and I agree in most cases you will get better quality by spending more money), then I agree that it would be better spent by buying the CANON EF 70-300mm f/4-5.6 IS USM

(Specifically note the model as there is more than one 70 to 300)

I ASSUME this is the model to which Crisscross is referring – at least it is my suggestion.

The other option in the price area of the EF-S18 to 200 and the 70 to 300 is:

EF70 to 200F4L,

which gives you a constant maximum aperture (think about it, read up on the value of this) AND with a few hundred dollars more, you can buy the EF1.4MkII, giving you a 98 to 280 F5.6.

Now note that the F4L I mentioned in that price range does not have IS (Image Stabilization) but have you thought through whether you need IS or not?

I guess I just posed more questions . . . choices, choices, choices.

WW

[Colin Southern]

Keep in mind also that as a rule, the bigger the zoom ratio, the more design compromises you'll see in lens performance - especially at either zoom extreme, and especially where one of the zoom ends gets into "wide" territory.

The other point I was was going to mention is that side-by-side 100% crops for the purposes of comparison bear little to no resemblence in real-world examples. It's a bit like the time where a bunch of audiophiles were blindfolded and had to rate 5 different sound systems - the specifications varied, but - just like lab tests of lenses - they couldn't tell the difference in a real-world test and thus all totally embarrased themselves by picking the cheapest system as the winner.

[Dave Humphries]

Keep in mind also that as a rule, the bigger the zoom ratio, the more design compromises you'll see in lens performance - especially at either zoom extreme, and especially where one of the zoom ends gets into "wide" territory.

This is certainly going to be true, laws of physics and engineering practicalities being as the are.

However,

The other point I was was going to mention is that side-by-side 100% crops for the purposes of comparison bear little to no resemblence in real-world examples. It's a bit like the time where a bunch of audiophiles were blindfolded and had to rate 5 different sound systems - the specifications varied, but - just like lab tests of lenses - they couldn't tell the difference in a real-world test

.. might be worth exploring. (He says preparing to learn something new and wipe the egg off his face )

I don't see how side-by-side comparison of 100% crops could NOT help judge technical quality of say, resolution, because unlike audio comparison it is not reliant upon human memory and there's no temporal element to consider (as with music).

However, I do accept that a lab test under ideal conditions for resolution might show lens A is sharper than lens B whilst not showing that lens A is so beset by flare that, in the real world, it renders the advantage back in lens B's favour. Is that what you meant Colin?
(this is the bit where I might learn from your experience by challenging your statement)

Thanks,

[Colin Southern]

I don't see how side-by-side comparison of 100% crops could NOT help judge technical quality of say, resolution, because unlike audio comparison it is not reliant upon human memory and there's no temporal element to consider (as with music).

However, I do accept that a lab test under ideal conditions for resolution might show lens A is sharper than lens B whilst not showing that lens A is so beset by flare that, in the real world, it renders the advantage back in lens B's favour. Is that what you meant Colin?
(this is the bit where I might learn from your experience by challenging your statement)

Hi Dave,

Nothing so "deep and meaningful" I'm afraid!

The point I was trying to make is that often people tear their hair out trying do decide which lens to buy based on reading a gazillion reviews and pouring over the side-by-side 100% crops whereas if you took a couple of real world shots and printed them out at a typical size then approx 100% of people probably couldn't even tell the difference, let alone tell which lens produced which image.

I think that people somtimes forget that lenses and cameras are make to take photos in the real world - not to be confined to "A -v- B lab tests" - I'll bet a lot more people would be less worried about the lenses they have if Photoshop only went to 12.5% zoom, and yet they lie awake at night worrying that at 100% view it doesn't look perfect when in reality the inperfections they're seeing can't be resolved in a normal print at anything less than 20 x 30 inches. To me it's a bit like saying "I'm thinking of buying a car to drive to the corner dairy 100 yards away. Initially I was thinking of a Bugatti Veyron, but some of the reviews I've read say that at 400km/hr the tyres only last 20 minutes - so I've thought perhaps a Porche 911 twin-turbo might be a better choice?" Whereas the reality is obviously that both are more than capable of doing the job and the "limitations" identified in the reviews really don't reflect real world applications - especially when real world results in many cases could be improved 5 fold with improved post processing.

That's how I see it anyway

[Dave Humphries]

Hi Colin,

I think exploring this might be helpful to others (as well as me), so I shall continue (do tell me to shut up if necessary).

Ok, I accept what you suggested earlier; about having a resolution 'good enough' tag rather than looking for the highest figure attainable. And also that the effects being greatly affected by the user's PP (or lack of) sharpening.

However, if we are to ignore certain factors (by declaring many as equal), some might say that makes choice even more difficult i.e. result even more 'hair tearing'. Maybe, but see below.

My current lens exhibits noticeable CA (chromatic abberation) about 5-10% of the time (in real world shots). So, if I buy a DSLR, or another similar bridge camera , I was thinking of looking to quantify how bad my current lens is, then compare this with newer models so I can be sure not to buy one that has worse CA along with all the other good features I'd like. Maybe this is a special case, although surely anyone upgrading will face similar issues, they probably know what they like least about their current camera or lens, and want to be sure to improve that aspect whilst not spending over the odds (e.g. for a Veyron) when a "mini" would do.

Finally I think the penny has dropped.

When I chose my current camera, I KNEW I wanted something that went to 28mm equivalent at the wide end, had a 10x zoom range, did close up/macro, had an alternative to the screen on the back for composing and could shoot RAW, all in a budget of £200. At the time, this ruled out 90% of compacts, etc. on the market, thus making my choice easier. I went for a bigger, more DSLR like, bridge camera rather than a compact in the end, trading the disadvatage of size (over my previous Nikon P&S) for the increased creativity possible with the manual controls available.

So I guess it comes down to working out what is important to the purchaser (and what is not), whether it be (in this thread) a superzoom lens, or a DSLR/flashgun/whatever.

For my next camera, I KNOW I want a tilty (& twisty?) LCD screen, as my old bones and eyes don't like getting into contortions to peer into the viewfinder or see the screen too far off axis. That immediately rules out so many DSLRs. A process of decision making based on what is important to me. Nikon or Canon? Pah! I don't care; neither fit my criteria It'll be Sony, Olympus, Fuji or Panasonic I guess.

There are less variables for a superzoom lens buying decision, but I suppose what we're saying for Spinningcone is look at things like; field of view (at wide or telephoto - which ever end is MOST important to him), max aperture, weight and size, internal focussing and ease of use *, rather than 'pixel peep' the figures and 100% crops. Not forgetting the earlier advice that 2 lenses; a WA zoom and a telephoto zoom will inevitably offer less distortions and better IQ than a full blown superzoom that spans the lot, IF he can cope with the reduced versatility of having to change lens more often.

* Go try it somewhere; take your camera and if the store is agreeable, expose some test shots to review at home (before making a decision), don't forget to take same shots with a your/a known lens, for comparison. Not sure whether this always going to be viable for people not living in cities though.

I hope those ramblings prove helpful to folks,

[Colin Southern]

Hi Dave,

I think we're pretty much on the same page here. The issue I find with most of the "reviews" though is that you'll read one where someone will rate it's sharpness or lack of CA as being one of it's greatest strengths - and then the very next one you read will mention the very same things as being it's greatest weakness ...

... so you read a whole lot more reviews and get a whole lot more conflicting opinions. So personally, I give a lot more weight to samples that I've seen - and if I can lay my hands on something and try it for myself then so much the better.

Perhaps I'm better off saying that internet reviews are just another decision making tool - albeit one that can backfire on you if you don't keep a healthy perspective. Probably the best known recent example was the Canon 1D3 Servo AF fiasco - if you went by what you read online you'd think that the camera was a total lemon to be avoided at all costs - the only problem is the VAST majority of those who actually owned one found that AF performance was it's greatest assett, not it's greatest liability. I lost count of the number of people I liaised with privately who on my advice went ahead and bought the camera - and each and everyone was blown away by it's performance. All in all I've come to regard online "reviews" with a healthy dose of skeptecism (did I spell that right?) - in my opinion many of them are heavily biased by writers pushing a personal agenda (or defending a position), and I'm sure too that the many a photographer shortcoming has manifested itself as a lens issue in an online report. I'm reminded of a couple of editions of Top Gear where Richard Hammond was allowed to drive a Formula 1 car ... I'd like to think that someone like Richard - by virtue of his job - would be streets ahead of the average driver in being able to come to grips with something like an F1 car, and yet it took him about 4 goes to even get it moving - he locked brakes all over the place and generally make for one very entertaining piece of viewing (at his expense) (it's on youtube if you ever want a laugh) - the same car in the hand of the Stig lapped the (damp) track in 58 seconds where your average supercar struggles to do it in 1:10 to 1:20. If they didn't know better, how many drivers would write a bad review on a F1 car? Unfortunately (or perhaps fortunately) not many of us get to drive an F1 car and write a review - and yet many photographers of all abilities get to write camera and lens reviews - and just as you never hear "I'm a really bad driver, so don't blame the car" you also never read "I'm a really bad photographer, so don't blame the equipment" when they write a review - what you do hear is a lot of authentic sounding feedback - it's just that in many cases what your do hear is totally contradictory - which is somewhat ironic in that since it's the same piece of equipment that they're reviewing - the biggest variable is thus the person doing the reviewing and in particular their level of skill and the degree of subjectivenes in their interpretation of the results.

I talk too much!

[Dave Humphries]

I think we're pretty much on the same page here.
I talk too much!

1) I agree
2) me too (usually)

[hsroxas]

I have not used the Tamron 18-270, but I did use and still have the older model which is the 18-200. Both lenses I think are both f6.3 at its telephoto end. To my mind, this is something that you should consider. It is not for the reason that it is a tad slower compared to Canon's f5.6, but rather because I experienced a lot of "focus hunting" specially so in low light. The noisy and rotating focus ring also annoyed me. In terms of image quality, I find the 18-200 best at f8 to f11, as most lenses will be anyway. I would suggest that you try on the Tamron first before making your decision. I am using a 30D, so I am not sure whether the concerns I raised will also be the same if the Tamron is mated to an XSI.

[Colin Southern]

Hsroxas, thanks for your input - it's great to have you with us. If you get a chance, pop a reply onto the introduction thread so we can all give you a proper "CiC Welcome"