Sigma 120-300mm f/2.8 EX DG OS HSM first impressions

[popo]

Some of you may recall I bought a used Canon 300mm f/2.8 lens (no IS version) in the past. I didn't keep it because of a combination of factors, biggest of which was the lack of flexibility a prime offered. Secondarily was the weight, which only made its limited use even more so. I didn't keep it for long and sold it on again.

Fast forward to now. Today I have received the *deep breath intake* Sigma 120-300mm f/2.8 EX DG OS HSM etc. While it is similar to the Canon, it differs in two important ways. One, it has a zoom, and secondly, it has image stabilisation.

The cardboard box it came in was no ordinary cardboard box. Although as shipped it was a regular rectangular box, you can re-fold the flaps into a convenient carrying handle! Nice. But that's only good for getting you home. Inside the box held in place by cardboard corner pieces was a padded soft carrying case as well as the manual and the usual other bits of paper. Lying in the bottom of the box was a strap which can attach to the tripod foot if you want.

Of course the lens was most interesting and I pulled that out. Heavy! The removable tripod foot was fitted on it, and has a somewhat long base section. It can be rotated around and out of the way for hand holding. I found the only position it didn't get in my way was about 11 o'clock position. Can't put it straight up else you obscure the distance window. To the right and it gets in the way of your right hand on camera body. To the bottom or left and it gets in the way of the left hand.

The body has two switches, one for AF/MF, the other is a 3 way switch for OS, with the usual off/on/one axis options. The zoom and focus rings are both large, with the focus ring closest to the body. I find both rings are very stuff and take some force to turn. I'm hoping this is only because it is new and not worn in yet, but equally it could be because it has to shift a lot of glass and it isn't going to get easier.

On the front you get a 105mm filter thread. Don't think I'll be getting much for this then! The hood is a cheap and nasty plastic thing not at all like Canon build ones. Even the plastic Canon hoods are nicer as they have the flock material inside to prevent light reflections. Sigma make do with a ridged pattern in the plastic but by eye it is not nearly as effective.

Putting it on a camera, hand holding it was about as stressful as the Canon was. It is heavy, no ways around it. I'll have to work on my arm strength again for this one. The OS really helps when looking througg the viewfinder. It is very effective and at 300mm I was getting sharp test shots at 1/30s on crop body. This is in line with a claimed 4 stop OS performance although I haven't tested it much yet. The OS makes a noise as it starts and stops, and the HSM sounds a little rattly compared to other implementations. Again, this might be due in part to them having to shift a lot of glass. The internal focus and internal zoom means it doesn't change length in use, nor does the front rotate in case you ever want to get a polariser for it.

AF speed, I'll need to do more testing here. It doesn't feel slow. It doesn't feel ultra fast. Competitive at least.

I'll have to end here for now. I haven't had a good chance to test it optically yet. There doesn't appear to be any significant focus offset on this sample, within expected tolerances. f/2.8 seemed sharp enough, but all this needs further testing in real world situations. I don't have my teleconverters at the moment as I've lent them away, so that'll be testing for another occasion.

[popo]

I managed to take the lens out to a park near where I work at lunch, so got some outdoors experience with it.

I'm starting to dislike the lens hood and lens cap. The hood is a typical fit where you slide it on and rotate it into locked position. But it just feels too flimsy and the lock doesn't feel secure. Also the lens cap popped off during transportation and was also loose when I put it back on. The lens cap design seems to be the same as other Sigma ones, but bigger to cope with the massive 105mm filter thread. Maybe that's a factor? I wasn't planning on getting a protection filter but the hood and cap combined are making me rethink, although in a quick search there doesn't seem to be many 105mm filters around!

On to more practical usage aspects. The zoom was pretty much like any other twist zoom to use. I haven't measured the rotational distance from end to end but it is more than can be comfortably done in one motion while retaining good grip of the lens. I also found the non-extending zoom to be a little disorientating. Because the lens felt long I psychologically thought I must be zoomed in, although when I look closer at the scale I could be towards the wider end.

Then there's the AF. I haven't had enough experience still, but I think it feels better at getting initial lock than the 100-400L for example. Both in terms to speed and accuracy. I *suspect* this might be due to the f/2.8 nature of the lens, which enables the f/2.8 sensitive double cross centre AF point on the 7D. I could test that later when I get my teleconverters back, and see how it performs at f/4 for example. It doesn't seem any better at tracking after lock, but I think that's more a limitation of the body than the lens. I also now suspect there is a tiny bit of front focus, but that's somewhat common with most "fast" lenses on my 7D. Bear in mind, at 300mm f/2.8 the DoF of a subject at 3m is just 1cm! So it doesn't take a lot of error to show up. I didn't really try for further subjects without the extenders.

And finally, the 4-stop OS definitely is a league beyond the 100-400L's ancient 2 stop, and I think may even be better than the 70-300L's IS too.

I've got a bunch of duck and goose photos to look through later tonight so samples will have to wait a bit longer.

[popo]

Not the greatest of samples but it's a start...


This little bird was hiding in the branches of a tree. The foreground branches got blurred out nicely although they still contribute to a contrast reduction. Tis is cropped, about half the original shot, so if I had a 2x extender on it, it would be perfect.




The focus caught well on here, although it isn't critically sharp as the shutter was too slow for the motion.



Looking at the samples I had, both in and out of focus, I suspect there isn't a major offset with the lens after all. A lot of the cases of "bad" focus had closer areas near the focus point in focus, so this is likely the usual AF point being bigger than you think thing going on. Not normally much of a problem unless the DoF is wafer thin...

Overall, none of the f/2.8 shots could I describe as critically sharp when pixel peeping, and it does perk up from stopping down. But it is still more than sharp enough to be usable.

[popo]

Some more testing down the local park.


Gull - cropped. f/4


Coot - cropped. f/2.8


Swan - NOT cropped. f/2.8

Above images can be clicked through to my stock dA account where you can download the full size images. RAW processed in ACR with sharpening in ACR only.

Wafer thin DoF when used wide open at closer focus doesn't help. The coot shop shows some bokeh into. Background bokeh is fine. Front shows signs of an outline effect in some areas of higher contrast.

Also found it a little funny. One thing I hated about the Canon prime was because it was a prime, but I didn't find myself zooming out much on this one. Also I had a look at the turning range, it's only about 2 hours of a clock face to go from end to end. Feels like more... maybe because of the size of the lens?

[popo]

I think I have got used to the weight already. I don't feel this lens in use any more, at least not significantly... I am kinda finding I use it on f/4 most of the time. The depth of field is just too shallow at f/2.8 unless you have the time to make sure the focus is spot on. I still go to f/5.6 or f/8 as necessary.

[maxjj]

Sounds like a fun lens, but why do you need it, especially as you are stepping it down. You seem to have all bases covered with the 100-400L and the 70-300L.

[popo]

When I get my teleconverters back it will be 240-600mm lens for those times when 400mm isn't enough. Actually 600mm probably isn't enough either, but the only step up is the 200-500 f/2.8 and that's a bit beyond my hand hold ability.

[RexGig]

Thanks for sharing, popo. Your impressions of the lens are useful, as I anticipate much coastal bird photography in the future, and I enjoy seeing your feathered friends.

[Thomas]

Hi popo!

Thank you for your helpful report of your impressions and the accompanying shots! This is a lens I have on my "watch"-list and I've heard good things about central sharpness and the ability of the OS. I have a fixed focal 300/4.0 and 400/5.6 and really find it limiting that you can't zoom back. This was the reason I tried the Sigma 100-300/4.0 albeit it has no OS and I got an awfully decentered copy. So combining 300mmm with f2.8 and the ability to zoom back to 120mm is certainly a very interesting proposition.
It'll be interesting to see how this lens works for you in the long(er) run.
Keep us posted!

[popo]

I haven't yet put it to use in my intended role, which is with extenders particularly to 600mm. I currently expect to be reunited with them within a week or so, and will give that a field test then. Unfortunately the weather forecast is very wet over that period, so all I might be testing is its water resistance.

[Thomas]

"testing is its water resistance"
Good luck, popo! And show us some 100% crops here, please!

[popo]

Have some quick 100% crops from the three samples provided earlier. If you go back to the earlier post with the gull/coot/swan in you can click through to dA, where in the top right corner you can download the full image.

I didn't process those significantly, just basic raw conversion in ACR. In particular, I did not apply my normal strength sharpening on them. The gull was at f/4, and if I remember correctly the shaded areas were very dark so I had to go fishing in the shadows to bring them back. The other two were at f/2.8, which as mentioned before are not the sharpest but are not that bad either. With more normal processing and typical output sizes you wouldn't notice that.

[maxjj]

how do you find focus speed and accuracy compared to the 70-300L or the 100-400L?
Hopefully, when you get your extenders back, that will not be affected too much.

[popo]

I haven't done any direct side by side AF speed comparisons, but my feel is it is in the same ball park as the 70-300L and 100-400L. Not slower, not faster. I suspect but can't say for sure the Sigma might get initial lock better, but I can't rule out this being wishful thinking from me. A possible reason for it to be true would be allowing the f/2.8 AF point to be active on the 7D.

[popo]

I just spent the day with the lens stalking birds again, including with my teleconverters. This is a sample at 600mm f/8 although at somewhat high ISO (2000) so not the greatest for pixel peeping as the following crops show.







Why f/8? Because we know it's soft wide open even without the teleconverter, so it's not going to get any better with. One stop down helps with sharpness. As a side effect, you have a longer focal length, generally requiring a faster shutter, and you're stopped down. This will be challenging in poor light. For slower moving subjects of course I could have reduced the shutter and relied on the OS, but I don't have any suitable samples of that.

The longer length once again shows up the lack of air stability for more distant subjects. Tracking AF seemed no worse than without. The weight was getting to me after some use. My arms ache now...