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Canon 300mm II & Sigma 120-300mm OS (1 Viewer)

micloi

Well-known member
Canon 300mm II with 2x III - Sigma 120-300mm with 2x II
100% Crop

The Sigma seems to be less than 300mm (as was the non-OS model)



f5.6 Canon / f5.6 Sigma
1%20CROP%20300mm%20II%20at%20600mm%202x%20III%20f5.6.jpg

1%20CROP%20sigma%20120-300mm%20OS%20at%20600mm%202x%20II%20f5.6.jpg


f6.3 Canon / f6.3 Sigma
1%20CROP%20300mm%20II%20at%20600mm%202x%20III%20f6.3.jpg

1%20CROP%20sigma%20120-300mm%20OS%20at%20600mm%202x%20II%20f6.3.jpg
 
The focal length of any lens with internal focussing (most) varies with focus distance.
Try again on something more distant than a test target.
 
I took these at around 5 meters which is the distance I try to get to when photographing small birds for best quality prints. Was looking at the quality of the photos, the focal length difference just happened to come up.

Will, nevertheless, try to photography something more distant next time I can get my hands on both lenses.
 
Almost all zoom lenses will only give the full zoom focal distance when shooting at infinity and even then there is an allowable tolerance. The nearer you are to the target then the less the true focal length will be with zooms.
 
I'm going to poke my nose in here; been reading about some impressive performance of the sigma recently so I'll be curious to hear which one of the two you end up going with. At half the cost if it can do what the canon does decently well then its a very attractive option on the market!
 
The problem with sigmas is they dont have a limit switch, this at times can lose the shot and that puts me off even though they have good glass.
Rob.
 
The problem with sigmas is they dont have a limit switch, this at times can lose the shot and that puts me off even though they have good glass.
Rob.

This is not true. The Sigma 300f2.8 OS does not have a focus limiter. The prime 500f4.5 does and I believe the prime 800f5.6 has one as well, but the 300-800 does not.

I agree that not having a limiter switch can be a real bummer but so can having a limiter switch e.g. when a bird comes unexpectledly close for just a few moments.;)
 
If I can chip in here.

Micloi used my 120-300os for this comparison shot and I have to say I was VERY impressed with the new Canon 300II in terms of colour, contrast and sharpness when the files were viewed on a properly calibrated monitor. Not sure the Canon is woth x2.5 the cost though but that is just me.

That said, I have tested the 120-300os against a 500f4 which I had earlier in the year, sold the 500 and kept the 120-33os.

To get back to the points raised in previous posts.

The lack of focus limiter is VERY annoying when a x2TC is used in dim light when the AF can be a bit slow. However with a x1.4 TC or when the lens is used bare the AF is so snap-on sharp you do not notice the lack of limiter.

The other two annoying things about the Sigma is: the lack of zoom lock which has been solved by using snugly-fitting WWS covers which prevent lens creep, and: I would REALLY like attachments on the barrel of the lens to apply a lens strap.

Otherwise, the 120-300os is a VERY nice lens at any price and for around £2000 it is an absolute steal.

Just my 2p worth.
 
Actually it looks like sigma compares quite well against Canon 300 2.8.. and it is way cheaper anyway. Thanks for comparsion images!

I still have antique EF 300 2.8L (non is) and thinking to get IS version, maybe 120-300 OS? dont know.. I just still love the IQ of this very old lens.
Once I made a test about interpolating 300mm image to 2x size vs. EF 2x TC.
http://tonskulus.kuvat.fi/kuvat/sekalaiset/pikseli/30060056_5D.jpg/full
100% crops: left 300mm, middle 300mm interpolated to "600mm", right 300mm + 2x TC wide open.
So yes, with 2x TC we get more detail.
 
I've read suggestions that among the announcements that Sigma is making on 10 January will be a new OS 300mm f/2.8 prime.

It's reasonable to assume that it will cost less than the 120-300mm zoom, while matching it for IQ, in a smaller package.
 
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I've read suggestions that among the announcements that Sigma is making on 10 January will be a new OS 300mm f/2.8 prime.

It's reasonable to assume that it will cost less than the 120-300mm zoom, while matching it for IQ, in a smaller package.


Interesting ....and I wonder if it will feature a focus distance limiter switch.
 
We can but hope, Adrian - you'd think that it would be easy enough to achieve, and God knows, it has been the thing (along with OS) that most people have been saying was missing from these lenses, for a long time.
 
Canon 300mm @ 1680mm (3 stacked TC's: Kenko 2x DG, Canon 2x III, Canon 1.4x III - Extension tubes, 12mm and 24mm, are used between the 1.4x and the 2x III and then between the 2x III and the 2x DG)
OPEN WIDE (f16)

Same test to follow with the Sigma tomorrow, watch this space!

1680mm%20f16%20copy%20800.jpg
 
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Canon 300mm @ 1680mm (3 stacked TC's: Kenko 2x DG, Canon 2x III, Canon 1.4x III - Extension tubes, 12mm and 24mm, are used between the 1.4x and the 2x III and then between the 2x III and the 2x DG)
OPEN WIDE (f16)

Same test to follow with the Sigma tomorrow, watch this space!

1680mm%20f16%20copy%20800.jpg

thats the most stacked iv ever come across :) does the job though .
Rob.
 
Comparison of the 120-300mm Sigma OS and the Canon 300mm II with stacked TC's at 1680mm!!!

First is the Sigma, 2nd is the Canon. Both open wide (f16)

120-300%201680mm%20f16%20800.jpg


1680mm%20f16%20copy%20800.jpg
 
Well the Canon is sharper...............

If I ever need to take pics of a tenner at f16 I'll bear that in mind...........

I thought you'd already sold your Sigma 120-300 OS?
 
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