Sigma 18-200mm f3.5-6.3 Lens For Sony Digital SLR Cameras

Got this for my birthday so can't comment on price etc., but have used it for a range of situations & thoroughly enjoy it - far more than the 18-55 that came with my SLR. PLEASE remember when comparing reviews that it is silly to give this a star-rating based on a comparison with a top-of-range big-name lens that costs 2-5 times as much; so I have rated it based on what I wanted it for.

RECOMMENDATION: this is a particularly FABULOUS lens if used in conjunction with Adobe Lightroom, because just one click on the appropriate lens profile will immediately (& non-distructively) rectify any distortion, vignetting, etc. I use LR 3.4 and created a preset appropriate to the lens correction profile for the lens & the outcome is so dramatic I would be hesitant to spend more on a named lens. If you don't use LR to import and manage your photos, then do some research & give it serious consideration, it is a professional tool that is probably all most of us will ever need (unless you are seriously into photoshop layers, etc).

Reflections on the lens:
(1) Fantastic range for a day-to-day lens. Superb in wedding receptions where you will be using every possible part of the zoom in a totally random way - go from the whole room to a candid portrait in seconds.

(2) MUCH better than changing lenses.... the wedding reception is the perfect case for this, with food, greasy fingers, lack of space etc.

(3) Clarity - my first few shots did seem a little softer than I expected, but then I found that when I compared them to shots from all my other lenses under similar conditions they were pretty much the same, if not sharper. BUT... if the lens is stopped down a couple of clicks from whatever the default wide-open is for the zoom, the sharpness goes up in leaps & bounds. Adding a flash at around F11 gives outstanding results.

(3) Distortion etc.... I didn't notice anything particularly shocking at any zoom when capturing architecture, but as I said, one click in Lightroom and it is all sorted along with much of the CA and all of the vignette.

(4) Slow? Yes, it would be nice to go wider than F6.3 on full zoom, but as with all lenses it is exactly the same story.... pay exponentially more for increasingly less if you want a bit more. Get a flash? Try raising the ISO... again Lightroom will sort out the colour noise superbly & do a fabulous job on the speckling if you want. Your choice - shoot RAW and pass it on to LR or shoot JPG and let the camera manage the noise, after all if you want totally crispy pictures you should have bought a massive prime. I don't think F6.3 is bad at all

(5) Image Stabilization: I have a Sony with the IS built into the body and it works brilliantly, so I don't need IS in the lens. The big names are lumbered with all their heritage technology but I suspect that one day soon they'll have to give in and come up to date. Sigma do an IS (OS) version for a lot more money if you want that.

(6) Lens creep. I mostly hand-hold so it doesn't creep as I'm holding it! Yes, when walking it will extend if not locked at 18mm. But the lens only creeps when pointing down & being moved, I find it stays put on a tripod, though I've not tried shooting vertically down. A broad elastic-band, as discarded by the postman, placed over the joint locks it in place if needed. Interestingly the zoom rotates the other way from my other lenses.

(7) Size & Weight. Much heavier than the kit lens, but contains a lot of glass. Feels very well built. Is actually the same length at 18mm as my kit 18-55 was at its shortest, so fits into my lowpro case we well. The lens-hood is gorgeous. At 200mm it may give a shadow to a pop-up flash, but I use a Speedlight on top of a sony-Nikon hot-shoe convertor so the flash is quite high & there is no shadow in shot.

(8) Focus. Fast enough, accurate enough, equal to the Sony equivalent SAM in my kit lens, faster than my Tamron 70-300. Just occasionally hunted for focus in a dark church. HINT - focus needs contrast, so lock onto where a black suit meets a white shirt and it goes there immediately and accurately even when very dark.

Summary: Excellent value for general use, lovely to use after the kit lens, does a really nice job, any minor shortfalls are easily managed with LR. Don't compare it with a £1000 lens, just think back to every lens-swap & dusty-sensor and realise how much more time you will have for taking pics. The only real contender is the Tamron which I'm sure is not far off and would probably get a similar review.

This is a quality lens but that goes without saying as you can expect nothing less from SIGMA!!

Pros:
Its perfect from macros to zooms, well built, smooth movement with crystal clear optics.
Comes with a handy petal-hood for outdoor shooting.
When zoomed in, the lens is not as large as the Tamron or the Nikkor (the latter not being applicable to Sony Alphas)
Using an all-in-one lens means no fussing around detaching and re-attaching!

Cons:
No in-built image stabilization (like with the Nikkor's)
The 'hold' button can only be used at its widest setting.

Bought to take to New York with me to reduce the amount of kit I would need to carry. The lens is solid and feels well built. There is some vinagaretting to the edges of the shot at it's 200mm end, but in fairness it's a £200 lens not a £1000 lens. The zoom feels smooth and the AF seems quick enough.

It is a sturdy "Jack of all trades" camera purchase, definitely an upgrade to the stock Sony alpha series 18-70 lens. As is the way with photography you always end up "wanting more" so if I'd had twice as much money I could have bought a lens twice a capable.