Sigma 50-500mm
'There's no such thing as a free lunch.'
Ok, I admit it. I got drawn into the whole 'never mind the quality, feel
the length' thing. Allow me to explain.
I was looking for a long lens to let me try out my wildlife skills, and
maybe a bit of sports work. But which one? I needed to go longer than 300mm
because I already had a 70-300mm zoom and I knew I wanted a longer reach
but did I go to 400mm, or 500mm? Budget constraints meant a 600mm was out
of the question so I was almost there and then I had a 'hang about!' moment.
Browsing the ads in the back of a popular weekly photography magazine, my
eye landed on an advert for a second hand Sigma 50-500mm. I remembered reading
about this lens when it was introduced and scoffing like many others that
such a range in one lens was bound to result in poor quality results. A
10x zoom range? Surely no human being could survive such extremes? But that
was then and this was now. It was an answer to my prayers. A good quality
short end zoom, combined with this monster, would allow me to cover sweeping
landscapes and still capture distant wildlife with just two lenses. It was
an EX lens, Sigma's badge of quality, so I should have no problem with the
optics, the little voice on my shoulder told me. The same little voice then
chipped in with 'don't forget the sensor magnification factor'. It was true,
bolting it onto the Nikon D100 I was using at the time would actually give
me, in 35mm terms, a 75-750mm f4.0/f6.3. A 750mm f6.3 for a price measured
in hundreds, not thousands, of pounds. That alone was worth investigation.
I was getting a bit giddy by now. Just a minute I thought, if I stick on
my 1.5x converter I get, furious mental calculations going on now, a range
of effectively 110-1100mm!! Ok, so it would be slower than a tractor in
treacle, and I would have to focus manually, but a 1100mm telephoto!!
So I bought it.
'Act in haste, repent at leisure' is a concept I am well acquainted with.
It was something that popped into my mind when I took delivery of my prize
a week later. I was expecting a big lens but I was still taken by surprise
by the sheer weight of this beast. Just a shade over 4lbs. The tripod collar
is conveniently formed into a handgrip, and with good reason. You will need
a good grip when lugging this lens around once a body is attached. After
just two weeks I had a monopod on order. No matter what I did I just couldn't
hold it steady in anything other than bright sunny conditions. If I'm honest
I couldn't hold it steady in any conditions, but sunny weather allowed me
a shutter speed fast enough to disguise my trembling. To be fair this is
probably more due to my naivety regarding long lens use than a fault of
the lens itself, but I was learning the hard way.
My inexperience was showing in other areas too but here the lens actually
helped. I had a tendency early on to zoom out to the length I wanted for
the final shot and then go looking for my quarry, but then if the subject
matter moved any faster than that treacle bound tractor I couldn't even
find it, let alone track it. Forget about taking a picture. Actually if
a subject moved at all I was lost. But here the zoom came into it's own.
I quickly learned that I could pick up an object at a wider setting and
then zoom in. Not always successfully but with practice my strike rate started
to improve. This was definitely an advantage over a prime telephoto as far
as I was concerned.
As I spent more time with this lens I started to understand it more. The
bulk and weight were a trade off for the quality of the optics and the construction.
Now that I was habitually mounting it on a monopod or, more often, a tripod,
I could appreciate the smoothness of its action and nice touches like the
zoom lock. My results were improving but still I wasn't entirely happy.
Little things irritated me. The aperture ring for example. Users of Nikon's
recent lenses will have no doubt noticed that this feature is absent. (Unless
they have only ever used recent lenses in which case they will have no idea
what I am talking about.) With these lenses the aperture is set electronically
from the camera body. This is the way of the future, but in an effort to
maintain compatibility with older bodies the manual aperture ring is still
present on the Sigma, though how you get to it once the lens is mounted
is anyone's guess. This is a very laudable effort on Sigma's part but I
wish they hadn't done it. To use it with an auto focus body this ring needs
to be set to f22. It's even marked in red to remind you. But here's the
rub. It's right next to mounting collar. So when you are attaching the lens
it is very easy to catch the aperture ring in the process and if you move
it even one notch the camera won't function. This caused me no end of sweating
and cursing the first few times as all you get is an 'E' error code but
no explanation as to the cause. It would seem the men in white coats at
Sigma spotted this issue as they saw fit to install a lock to prevent this
very problem occuring. Trouble is, the way the lock works, a tiny slider
that moves toward the camera body to lock, makes it very easy to unlock
by accident when putting the rear lens cap on, and without knowing until
the next time the lens is used. If only it slid away from the camera body
to lock. Like I said, little things.
The filter size was another. At 86mm the only time I have seen a larger
front end was on the 45-90mm zoom on my Bronica. On a pure telephoto lens
filters are not normally an issue, but the range of this lens implies you
are expected to use it in circumstances where filters would play their part.
Indeed the focussing arrangement results in a non-rotating front end, so
in demand with the landscape crew as it makes using graduate and polarizing
filters so much easier. I'll let you do the maths but a circular polarizer
and a set of ND grads that will cope with an 86mm mount is likely to be,
shall we say, not cheap.
Filters aside, and assuming you succeed in getting it mounted without issue
your troubles are not necessarily over. I mentioned earlier that the bulk
and weight were a trade off against the quality of the construction and
I stand by that, but the trade off you make to allow for the relatively
low price is speed. We have all suffered 'lens envy' watching the professionals
at sports events with their huge f2.8 telephotos, but consoled ourselves
with the knowledge that they have had to get a second mortgage to pay for
them. As the economist Milton Friedman famously said, 'There's no such thing
as a free lunch', and the price you pay for the biggest zoom range on the
market and a 500mm reach at the long end, for under £1000, is a maximum
aperture of f4.0 at 50mm closing to f6.3 at 500mm. This has caused me problems
too many times for me to ignore it. Too many times I have missed a shot
because the auto focus just didn't have enough to work with. Even slight
drops in the light levels have caused me to have to switch to manual. And
that's a shame.
It's a shame because in most other regards this is a cracking lens. It is
built like a tank but once suitably mounted its weight becomes a positive
in terms of reducing vibrations or combating a windy day. The quality of
the glass is excellent and if you can get it to focus the results will be
crisp and sharp. Overall though, all things considered, I have to admit
to being just a touch disappointed. Size isn't everything. A 10x zoom range
sounds great, a lens for almost every occasion, but I would never use this
lens for portraits for example. Truth be told I have probably rarely used
it below 200mm. So I am carrying round a great deal of spare capacity.
So, in summary, if you are considering the purchase of one of these lenses
don't let me stop you, it's not a bad lens, but give some serious thought
to either the Nikon 80-400mm VR or, if you don't use Nikon bodies, the Sigma
80-400mm OS.
That's what I am doing.
Update 09/11/07
When I originally wrote this review I didn't include any sample shots as
I felt the conversion to the web and the variances on monitor settings would
mean they wouldn't be a fair representation of the lens. However, from feed
back I have received it seems that test shots would be appreciated. So,
here are some sample shots. Never let it be said that I don't listen to
my readers!
All the following were taken over two days on reasonably bright November
afternoons. The camera is a Nikon D200 set to RAW capture. White balance
is set to auto and in-camera sharpening is off. For all the tree shots the
lens was set at f8 for consistency and the ISO was set to 100. The camera
and lens combination was mounted on a tripod to minimise any human vibration
and the shutter was released by remote for the same reason. The duck was
taken as more of a field test at 500mm with the kit mounted on a monopod
and with an aperture of f6.3 (the best I could do at 500mm). The ISO was
wound up to 400, which gave me a shutter speed of 1/100th, and the shutter
was fired in the 'normal' way.
Post capture manipulation consisted of a slight tweak to levels, one pass
of unsharp mask (amount 100%, radius 1.0, threshold 0 for the tree and 150%,
1.5, 0 for the duck) and then conversion to JPEG at the maximum quality
setting to make them fit for web use.
I think that's everything. Oh, one last thing, I was approximately 150ft
from the tree and 60ft from the duck, and I used auto focus for all the
images. I hope you find them useful.
50mm
300mm 
500mm 
'Duck' 
About the author: David Stanley is a freelance photographer concentrating
on landscape
and travel images. He has growing portfolios of royalty free images
with Alamy
and istockphoto.
For more articles and reviews, along with a selection of his work available
as open and limited edition prints, please visit his website at www.davidstanleyphotography.com.
(If you are reproducing this article please ensure you include the 'About
the author' footer in full on each occasion. Thanks.)
