100-400 mk2 vs sigma 150-600

[paulbrogden10]

Hi all been thinking about the sigmas 150-600 both s and c vs 100-400 mk2 any comments the sigmas are cheaper and have much longer reach.

sigma c 150-600 £750

sigma s  150-600 £1200

Canon 100-400 mk2 £1400-1700

The sigma c seems a bargin dont it?

[paulbrogden10]

I am not supprized since the canon is around 383mm not the advertised 400mm

[paulbrogden10]

would you be talking about the sigma 120-300mm 2.8 it weighs a ton I believe.

[TTMartin]

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@paulbrogden10 wrote:

would you be talking about the sigma 120-300mm 2.8 it weighs a ton I believe.

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Actually the Sigma 150-600 OS Sport and the Sigma 120-300 f/2.8 have very similar weights. I have the Sigma 120-300 f/2.8 and use a 2X TC with it very successfully. So I was looking for weight reduction and went with the Canon 100-400 L IS II.

[ebiggs1]

Bob
Boston, Massachusetts USA

"There are, after all, such things as constant-aperture zooms"

But we are not talking constant aperture lenses.  Are we?  So that statement is moot.

If the measurements are made at full aperture, say 150mm @ f5 than at 151mm it will not be f5.  It may be f5.0000001 but it will not be f5.  It may not be linear either.  You can't increase the focal length without increasing the other.

Feeling persnickety this morning Robert?

[TTMartin]

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@paulbrogden10 wrote:

I have also come to a conclusion which is casing me alot of un-sureness. As you guys know I did own the canon 100-400II grey import. I was convinced some thing was wrong with it but when I tested another copy in store focus was still slow. camera used 7D and 600D. After much research I have come to the conclusion that it is possible their was nothing wrong with the lens. I have learned that some cameras may not be delivering enough power to the auto focus motor. This also would account for the battery's not lasting very long when I used the lens. This also means the critics who defended the lens may be right to do so.

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That is the reason I use a battery grip with dual batteries with both my 7D and 7D Mk II and larger lenses, either the Sigma 120-300 f/2.8, Sigma 150-500 OS or the Canon 100-400 IS II.

There are reviews that say the Sigma 120-300 f/2.8 DG HSM (non-OS) is slow to focus, but, by using the battery grip with it, I didn't find that to be an issue.

[ebiggs1]

"I have the Sigma 120-300 f/2.8 and use a 2X TC with it very successfully."

I also have the 120-300 but I prefer the SIgma 1.4x on it.  It is a real nice combo.  One of the rare places where a tele converter works.  Works out to approx, 170-420mm @ f4.

[ebiggs1]

B from B

A constant aperture lens changes magnification just in the front lens element.  So it can maintain a constant f ratio.  The entrance pupil increases its diameter because of the magnification change as you zoom.  The aperture diameter remains constant,  thus keeping the f ratio constant.

[Waddizzle]

"I did see a video of a 1DX using the lens and the auto focus was like 3 times faster than my combo. I really think canon should have addressed this issue."

I believe that Canon addressed that issue years ago.  It's called a battery grip.

[ebiggs1]

" It's called a battery grip."

Yes indeed!  

[RobertTheFat]

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@Waddizzle wrote:

"I did see a video of a 1DX using the lens and the auto focus was like 3 times faster than my combo. I really think canon should have addressed this issue."

I believe that Canon addressed that issue years ago.  It's called a battery grip.

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You make a valid point. But truthfully, I've never seen that advertised as an advantage of a battery grip. The BG is usually billed as a way to shoot more pictures without having to change the battery, rather than a way to maintain sufficient current flow through the autofocus motor. I've never been a great fan of battery grips, feeling that the longer time between battery changes didn't justify the additional size and weight. But if I had a large lens that I thought was focusing too slowly, I might feel differently now.