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Sigma AF 50-500mm 
f4-f6.3 EX APO RF HSM

by VividLight Staff
Sigma AF 50-500mm f4-6.3 EX APO RF HSM 

At a Glance
Filter Size:
Lens Hood:
Tripod Mount: removable
4.1 lbs
3.7"x9.25" (13.7" extended)
Front Rotate w/Focus:
Close Focus:
3.3' @ 50mm, 
9.8' @ 500mm
Macro: No
HSM Mounts: Sigma, Canon EF, Nikon D 
Non-HSM: Minolta, Pentax
Other: Soft case included.

Verdict: Thumbs Up

Call me a skeptic, but I fully expected this lens to come up short in our testing.  50mm to 500mm is a HUGE zoom range, and lenses with huge zoom ranges usually perform poorly at one or the other extreme - or at least that's always been the rule of thumb.  But these days lens designers at all the major lens manufacturers have been breaking the old rules.  By the end of the test the only discussion among the staff was how soon do we buy one for staff use.  While we may like much of the equipment that crosses our threshold, there are limits as to what we can buy for ourselves.  Accountants have no sense of humor you know.  Suffice it to say this lens has made our short list.

Before we dive into the details let's hit the high points of what's good about this lens.  First is it's size, while this is no mini-zoom, it's similar in size to the Nikon 80-200, making it easy to carry in a mid-size camera bag.  Most zooms in the 500mm range are big hefty monsters.  At 4 pounds it's no light weight by most folks standards, but it's considerably lighter than most lenses in this focal range.  It's well balanced.  We were successfully able to handhold shots up to 300mm with this lens.  At 500mm, and even at 300mm for that matter, you ought to be using a tripod.

The built in magnesium tripod collar is rock solid, locking in positively, and unlocking with an easy twist that allows you to rotate the lens without moving your tripod head.  I find it's much easier to spin the lens within the mount to line the camera up for verticals than to reorient the whole kit on the ball head.  The tripod mount also has a contoured grip making it easier to carry.

We also found that this lens worked well with an inexpensive teleconverter we had along for the ride.  We suspect it would perform even better with Sigma's own 2x converter.  With the converter we now had a lens with a 1000mm reach.  


At 500mm and with a 2x converter

As expected with a maximum aperture of f6.3, yielding an actual aperture of f12.6 with a 2x converter, autofocus was out of the question.

Making Sense of Sigma's Alphabet Soup
EX - Sigma's line of professional lenses.

APO - Indicates the use of apochromatic lens elements.  APO, like Nikon's ED glass and Canon's UD glass.  These low dispersion glass elements effectively eliminate chromatic aberration or color fringing resulting in sharper images (chromatic aberration is particularly troublesome in fast telephotos).

RF - Rear focus, only the rear element group moves to focus the lens.  This creates a faster focusing, quieter lens.

HSM - Hyper Sonic Motor.  Sigma's version of a Silent Wave/Ultra Sonic Motor.  It is extremely fast and almost silent. 

We took this lens along with us on our trip down Maryland's Eastern shore and over to Assateague National Park.  Under these less than ideal conditions we were impressed by how quickly the lens focused, whether at 50mm or 500mm.  

The lens felt well balanced, and it's size and weight quickly led to comparisons to the 80-200 f2.8 Nikkor we had along.  This is high praise as we consider the 80-200 f2.8 to be a "money" lens - meaning that you can always count on it for tack sharp images.  

Sigma provides a lock button on the left side of the lens body.  It's a handy way to lock down the lens at 50mm while it's in it's case.  This lens has a tendency to creep a bit when pointed near vertical and according to Sigma's literature the lock button is supposed to help correct this problem.  We found with our sample lens that the lock was only really effective when the lens was between 250-500mm.  From 100-250mm lens creep could be induced whether the lock was activated or not.  Since we generally weren't shooting vertically this wasn't much of a problem for us.  But if you'll be doing a lot of vertical work this "feature" could get to be a pain in the backside pretty quickly.

Did we already mention how fast this lens focuses?  Even in relatively low light focus was fast and accurate.  A real benefit for those of us shooting landscapes and wildlife is the fact that the front element doesn't rotate.  So set you polarizer or split neutral density filter and forget it - if you can find one.

One of the downsides of this lens is that it takes rather uncommon 86mm filters compared to the more common 77mm filters found on Nikon and Canon zooms.  We received this lens a few days before departing on the Chesapeake trip and were unable to find any filters in this size at several local shops that cater to professionals.  We then contacted a large mail order company.  

Of the four "standard" filters we shoot with, polarizer, warm polarizer, 2 stop ND, and ND grad,  only two were in stock.  It would be a four week wait to special order the other two, and he was concerned about guaranteeing the two he had next day as he was only showing one of each in stock.  We opted to shoot naked down on the Chesapeake instead of risking it.  The other surprise was the price differential.  Those four filters in 77mm size would total $215.00.  Those same filters in 86mm size would total a whopping $456.00, a difference of $241!  

Don't forget that difference assumes that you don't currently own any of those filters.  While this wouldn't keep us from purchasing this lens, the fact that it won't accept any of our existing filters is a bit of a kick in the pants as it raises the actual cost of the lens by about $450 (assuming you shoot with these types of filters).

While we did a good bit of shooting handheld, we found that the majority of our shots were taken from a tripod.  The lens was well balanced shooting handheld in the 100-200mm range, and even out to 300mm.  Beyond that a tripod is pretty much a necessity.  Frankly, rather than one or two test shots at 50mm I'm not sure we used it under 100mm at all in the field.  I can think of instances when following an active subject when it would be advantageous to be able to pull into 50mm, but in practice it's simply more comfortable when shooting at that length to switch to a lighter lens.

You'll need a reasonably large camera bag to hold this lens, particularly if it's mounted on a body in your bag.   In the bag that wonderful tripod mount that we raved about seems like a playful puppy as it manages to snag anything that comes near it.  But this is jut the nature of big lenses.  If you're traveling light, this lens travels well mounted to body slung over your shoulder.  Locked at 50mm it's reasonably compact and won't beat you up the way some longer lenses can when carried this way.

A last niggling complaint is the case provided by Sigma.  It's OK on it's own, but these things are never used on their own.  It's not big enough to accommodate the lens with a body attached, and it doesn't have and provision for strapping it to the outside of a camera bag or onto a belt.  For $1,000 we found that we were wishing Sigma had spent some R&D time on the bag as well.

But what about the images?  The discussion coming back up the Atlantic coast was that the lens had performed admirably in the field, but the quality of the images would be telling.  Frankly we were very happy with the images.  The were sharp and contrasty with good color saturation and no signs of color fringing when examined with a 22x loupe on a light table.  Subsequent 13x19 prints confirmed these initial impressions.

On the Eastern shore we used the lens primarily for landscape work.  In Assateague we shot wild horses, deer, and wild birds.  All of which were relatively stationary subjects.  

As a final test we took the 50-500 to the ballpark, shooting a men's over 30 hardball league.  It was a dark rainy afternoon.  Since it was a day game the lights in the ballpark weren't on.  In this low light we found ourselves wishing the lens was a bit faster.  At f6.3 we simply weren't able to stop the action the way we would have been able to on a sunny afternoon, or with a faster lens.  

But that is the compromise that makes this lens possible.  Faster glass would be significantly heavier in both pounds and price.  500mm f4s go around  8/8.5 pounds and $7,150/$6,500 for Nikon & Canon respectively and both are significantly larger.

Sigma has produced a fine lens that does everything you could ask of it and more for the price.  Now if we can just convince the accounting department...


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These days lens designers are breaking the old rules
































Did we already mention how fast this lens focuses?


















Beyond 300mm a tripod is pretty much a necessity







text and photography copyright 2001 Vivid Light Publishing