Canon 100-400 vs. Sigma 150-600 C for Birding

After having used the Sigma 150-600 C for some time now, I think I can confidently conclude that:

1) I have no regrets selling my previous 100-400L for the Sigma.
2) If money's no issue, I'd like to get the 100-400L II, as well. These two lenses aren't apple to apple comparison, really.
3) 100-400L is superior for air shows and probably BIF and other action shots than the Sigma.
4) The Sigma at 600mm and 100-400L (original) at 400mm are about the same sharpness-wise, perhaps even a slight edge to the Sigma.
5) When the subject is very far, however, I believe 100-400L does a better job given the same atmospheric influence.
6) I can rely on 100-400L at pretty much all circumstances; with the Sigma, I need to be lot more selective.

Tom Reichner wrote in post #18636479
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Not for me. . I'm not interested in fairness - I am interested in usefulness. . If the Sigma is just as sharp wide open as the Canon at 400mm, then why would I change?

I am looking for confirmation that the Sigma is better - a.k.a. more useful - than my Canon.

If I am going to give up the range from 100mm to 150mm (which is very important to me), then I need to know that I am gaining something equally important.

If 600mm wide open isn't tack sharp, then there would be no point for me to make the change because I wouldn't really be gaining anything because that would cause me to consider the long end of the zoom to be unusable.

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I would like to see some wide open shots from the Sigma, from an experienced long lens shooter, as well. From the bits that I've seen, and from testing out the Tamron version, they tend to get...mushy, wide open above 500mm. I wound up giving in and picking up the Canon MkII to replace the MkI and would be *really* hard pressed to attempt to replace it with one of those longer zooms. I was able to get equivalent results by cropping my 400mm shots and then upsizing the file in LR, compared to the straight 600 shot from the Tamron I tried. The Sigma's notably better than the Tammy, but I'm just not convinced it's *that* much better.

Tom Reichner wrote in post #18636479
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Not for me. . I'm not interested in fairness - I am interested in usefulness. . If the Sigma is just as sharp wide open as the Canon at 400mm, then why would I change?

I am looking for confirmation that the Sigma is better - a.k.a. more useful - than my Canon.

If I am going to give up the range from 100mm to 150mm (which is very important to me), then I need to know that I am gaining something equally important.

If 600mm wide open isn't tack sharp, then there would be no point for me to make the change because I wouldn't really be gaining anything because that would cause me to consider the long end of the zoom to be unusable.

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I believe I can confirm that the Sigma C at 600mm is tack sharp. However, that depends on two things: 1) your camera body. On my 5DIII, I'm quite impressed with the sharpness at 600mm. On (someone else's) 5DIV, a step better, for which reason 5DIV has suddenly made my to-buy list; 2) lens to subject distance. Longer the subject is to your lens, I believe the Sigma becomes lot more susceptible to atmospheric distortion than the 100-400L.

A sample shot, in backlit condition (RAW to JPEG resizing knocked off a bit of sharpness):

600mm
1/400 sec
f/9
ISO 800

SYS wrote in post #18636508
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600mm
1/400 sec
f/9
ISO 800
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Another:
600mm
1/250 sec
f/8
ISO 800

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I am curious about your settings - why did you choose to use f9 and f8 when it doesn't appear that added depth of field was aesthetically favorable? . I mean, when there are branches in the background, we are normally trying to blur them out more, not make them sharper. . I am just wanting to understand the reasoning behind your aperture selection.


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Tom Reichner wrote in post #18636530
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I am curious about your settings - why did you choose to use f9 and f8 when it doesn't appear that added depth of field was aesthetically favorable? . I mean, when there are branches in the background, we are normally trying to blur them out more, not make them sharper. . I am just wanting to understand the reasoning behind your aperture selection.

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It's pretty much my "default" aperture shooting mode with the Sigma, because I don't see any evidence that, with a long zoom lens like the Sigma at 600mm FL, there's any visible difference, i.e., "aesthetically" more pleasing or not, especially with branches that are so close by, in the outcome. I'm of course extremely conscientious of my aperture choice when I'm using a shorter lens that can go really wide. I'd be very interested to see any evidences of appreciable differences with the aperture choice with the lens, again, at 600mm FL.

Snydremark wrote in post #18636493
I would like to see some wide open shots from the Sigma, from an experienced long lens shooter, as well. From the bits that I've seen, and from testing out the Tamron version, they tend to get...mushy, wide open above 500mm. I wound up giving in and picking up the Canon MkII to replace the MkI and would be *really* hard pressed to attempt to replace it with one of those longer zooms. I was able to get equivalent results by cropping my 400mm shots and then upsizing the file in LR, compared to the straight 600 shot from the Tamron I tried. The Sigma's notably better than the Tammy, but I'm just not convinced it's *that* much better.

Are you talking about the Tamron 2? I've been looking at the threads here for both the Sigma C and the Tamron 2.... from the photographs here, the Tamron seems to give better results.

I have the 100-400ii and with the 1.4X TC, I'm now getting decent results.... but nowhere near a Canon big white.

SYS wrote in post #18636543
It's pretty much my "default" aperture shooting mode with the Sigma, because I don't see any evidence that, with a long zoom lens like the Sigma at 600mm FL, there's any visible difference, i.e., "aesthetically" more pleasing or not, especially with branches that are so close by, in the outcome. I'm of course extremely conscientious of my aperture choice when I'm using a shorter lens that can go really wide. I'd be very interested to see any evidences of appreciable differences with the aperture choice with the lens, again, at 600mm FL.

I would think shooting at a longer focal length where aperture isn't a concern you would open the lens up to get more shutter speed thus reducing the chances of user error getting soft shots by having slower shutter speeds.

For me and the type of images I'm after I'd rather be wide open when I can...mainly to keep the shutter speed up and also blur the background as much as possible.

I'm fortunate to own both, and I use the 100-400ii more often. A few points:

I like f/5.6 better than 7.1 or f8, which is where I need to use the Sigma for best sharpness.
The sigma is indeed very sharp at 600 mm, much more so than its predecessor.
I like the more versatility of the 100mm wide end of the canon.
I find that image quality with extreme cropping of an image from the Canon at 400 is still good. (24mp cropped to 6mp or so)

here is one of my favorite images from the sigma at 600mm:

Phoenixkh wrote in post #18636583
Are you talking about the Tamron 2? I've been looking at the threads here for both the Sigma C and the Tamron 2.... from the photographs here, the Tamron seems to give better results.

I have the 100-400ii and with the 1.4X TC, I'm now getting decent results.... but nowhere near a Canon big white.

Good question; for clarity, I am referring to the mkI of the Tamron.

rjeske wrote in post #18636692
I'm fortunate to own both, and I use the 100-400ii more often. A few points:

I like f/5.6 better than 7.1 or f8, which is where I need to use the Sigma for best sharpness.
The sigma is indeed very sharp at 600 mm, much more so than its predecessor.
I like the more versatility of the 100mm wide end of the canon.
I find that image quality with extreme cropping of an image from the Canon at 400 is still good. (24mp cropped to 6mp or so)

here is one of my favorite images from the sigma at 600mm:

Excellent image there; I can see why it's a fave. Is that the full frame or a crop from a wider shot?

Duane N wrote in post #18636691
I would think shooting at a longer focal length where aperture isn't a concern you would open the lens up to get more shutter speed thus reducing the chances of user error getting soft shots by having slower shutter speeds.

For me and the type of images I'm after I'd rather be wide open when I can...mainly to keep the shutter speed up and also blur the background as much as possible.

Can't disagree with your points. Guess I'm a bit wary of shooting wide open with the Sigma unlike with my other lenses.

Tom Reichner wrote in post #18636530
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I am curious about your settings - why did you choose to use f9 and f8 when it doesn't appear that added depth of field was aesthetically favorable? . I mean, when there are branches in the background, we are normally trying to blur them out more, not make them sharper. . I am just wanting to understand the reasoning behind your aperture selection.

SYS wrote in post #18636543
It's pretty much my "default" aperture shooting mode with the Sigma, because I don't see any evidence that, with a long zoom lens like the Sigma at 600mm FL, there's any visible difference, i.e., "aesthetically" more pleasing or not, especially with branches that are so close by, in the outcome. I'm of course extremely conscientious of my aperture choice when I'm using a shorter lens that can go really wide. I'd be very interested to see any evidences of appreciable differences with the aperture choice with the lens, again, at 600mm FL.

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Well then I guess what I would like to know is why f8 or f9 is your default aperture. . I mean, why do you habitually use an aperture that demands that slower shutter speeds be used?

What I am trying to get at is, do you stop down because the lens is sharper at f8 or f9 than it is wide open?

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Tom Reichner wrote in post #18636834
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Well then I guess what I would like to know is why f8 or f9 is your default aperture. . I mean, why do you habitually use an aperture that demands that slower shutter speeds be used?

What I am trying to get at is, do you stop down because the lens is sharper at f8 or f9 than it is wide open?

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I've had this lens for about two to three months now, so I haven't done much testing to really find that sweet spot in terms of aperture. I just started off with that aperture range, and it has worked really well for me. I AM getting tack sharp photos, and that's the bottom line. Has my aperture range contributed to tack sharp results? Or, at least more keepers? Maybe. Would I get the same results with wider aperture range and the same number of keepers? Maybe. Since I'm not hurting in terms of speed for taking bird "portraiture," I just left it at that, i.e., what worked for me. Now, when I'm shooting BIF or air shows like a week ago, it's a different story. I'm NOT advocating my aperture range, of course. Now, because of this discussion, I'm rather interested in shooting at wider apertures and see the difference. Don't know when my next outing is going to be, but I'll report back on this. I'll shoot at widest with faster SS and see if I get 1) more keepers, and 2) more pleasing images.

Here is an example of the Sigma at 600 wide open, hand held and cropped.

IMAGE LINK: https://flic.kr/p/JrDF​dY