Trying to find a zoom that can handle both portraits and action.

jamesgoff3600

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Hello everyone!
This is my first post here! :)
I have a canon 80d and I have a 55-250 stm and a canon 70-300 is usm.
I am looking into getting a lens so that I can take portraits and also be able to capture action, meaning fast focusing and accurate focus. I have been looking into the canon 70-200 f2.8 because I rented it and it was so much better than my current lenses! But what are your thoughts on the sigma 50-100 f1.8 vs a 70-200 f2.8 for a crop camera? I know the 70-200 is a workhorse but using it on a crop camera it's like an f4 lens so the bokeh won't be like it is on full frame. I know that I am losing the 100-200mm range with the sigma but with a 1.8 aperture in a zoom lens is tempting. It's equivalent to using an f2.8 lens on full frame and I've read that it's incredibly sharp.
How would you compare these two lenses? Which do you think would be best for a crop camera? I do plan on eventually going full frame one day and the sigma is only efs mount, but I probably won't be buying full frame for a few years.
Thanks!

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The 50-100 is the only f/1.8 zoom I am aware of for a still camera. As such, it's beyond comparisons with common lenses like 70-200 f/2.8 or f/4 zooms. At 50-100mm in length, the Sigma is also more-useful indoors or at close range than any 70-200 lens. One cannot compare a 50-100 f/1.8 with a 70-200, on a crop-freame body. One is MADE FOR APS-C...the 70-200 was never, ever "made for" APS-C, but is a holdover from the 24x36mm 35mm film era.
 
Research the 50-100 lens, I've seen reports of focus issues with that lens. Some have the problem, others don't.
This puts into question its reliability for accurate focusing.

The 50-100 does not have IS, which I consider a requirement today, in any of my longer lenses that will be used hand-held.
Without IS, you are back to relying on technique to stabilize the camera at lower shutter speeds.
Is 100mm long enough that it needs IS? Depending on what you are shooting, the answer could be yes. For some, 100 is short enough that they can hold steady without IS. But if you are in LOW light, and down at 1/30 sec or slower, you will wish you had IS.

Specifically, what kind of action photos are you talking about? And where are you vs the subject?
The 50-100 will work for some sports and not for others.
  • Example1, the 50-100 would work on the soccer sidelines, but not well if you are up in the bleachers. In the bleachers, you need a longer lens because of the added distance from the bleachers to the sideline. But even on the sidelines, it does not have the reach to reach to the other side of the field.
  • Example2. It would probably work well for gym volleyball or basketball from the bleachers. A long enough reach to work from the bleachers, and fast enough to deal with the lower indoor lighting.
But remember the old saying "jack of all trades, is a master of none."
So don't expect it to do everything.
 
Sigma used to do a 50-150mm f2.8 OS lens. Supposedly very good. Might fit the bill if you can find one used
 
First of all, the "Crop factor" has nothing to do with aperture, so f2.8 is f2.8 is f2.8. A 50-100 f1.8 while fast, doesn't sound like an especially useful range to me, especially for sports work. You would also be working with razor-thin DoF which could make sharp images difficult to attain. Wide open at 25, and at 100mm your f1.8 lens is going to have about 1/4" total DoF whereas your 2.8 will have 2' 1"; over 40% more; when you're dealing with such a narrow range to begin with, 40% more is a lot (notwithstanding the fact that of course you can shoot the f1.8 at 2.8, but they why not just buy the 2.8 to begin with?).

I can see it being an okay portrait lens, assuming the optics measure up, but for sports/action work? Pass.
 
What's your budget ?? ... that's usually most people's limiting factor.
 
First of all, the "Crop factor" has nothing to do with aperture, so f2.8 is f2.8 is f2.8.

John, the way crop-factor gets hooked into aperture is via depth of field calculations. It's technically based on the photographer's behavior.

For purposes of calculating exposure, f/2.8 is f/2.8 is f/2.8. For purposes of calculating how much depth of field you get, there's a nuance where you multiply the focal ratio by the crop factor. But again... that's based on the presumption that a photographer will change their subject distance when using a crop-factor camera vs. a full-frame camera (assuming the same lens focal length).

E.g. if you wanted to compose the frame for a certain physical size (say it's head & shoulders portrait). With a full-frame camera you'd stand at some distance to get that composition. With a crop-frame camera you'd stand a bit farther away to get the same composition. When you step farther away to achieve the composition, the DoF increased and that means the amount of background blur decreased.

How much did the blur decrease? It turns out... mathematically if you multiply the aperture by the crop-factor... you get the same DoF.

E.g. if I got a certain amount of blur at 200mm & f/2.8 with a full frame camera, then use that same 200mm & f/2.8 with a crop-frame camera then the blur is reduced. The reduced blur in the crop-frame camera at f/2.8 will match what a full-frame lens would have done if I multiplied the true focal ratio by the crop-factor (in this case, f/2.8 x 1.6 = f/4.5).

Here's a YouTube video that demonstrates how it works (with real photos):

 
Sigma used to do a 50-150mm f2.8 OS lens. Supposedly very good. Might fit the bill if you can find one used

Yes, the 50-150 DX is a more practical sport lens, similar to a 70-200 on a FX/FF camera.
Unfoturnately, the VR version seems to have be built in a 70-200 f/2.8 shell, so there was no savings of bulk or weight.
Then Sigma discontinued it. DRAT
 
First of all, the "Crop factor" has nothing to do with aperture, so f2.8 is f2.8 is f2.8. A 50-100 f1.8 while fast, doesn't sound like an especially useful range to me, especially for sports work. You would also be working with razor-thin DoF which could make sharp images difficult to attain. Wide open at 25, and at 100mm your f1.8 lens is going to have about 1/4" total DoF whereas your 2.8 will have 2' 1"; over 40% more; when you're dealing with such a narrow range to begin with, 40% more is a lot (notwithstanding the fact that of course you can shoot the f1.8 at 2.8, but they why not just buy the 2.8 to begin with?).

I can see it being an okay portrait lens, assuming the optics measure up, but for sports/action work? Pass.
Actually yes, crop factor does affect the perceived aperature. The amount of light coming into the lens and hitting the sensor will be the same on both full frame and crop at the same aperture but on crop the depth of field won't be as narrow as on full frame at the same aperture. To find out what aperture it's equivalent to you have to multiply the aperture by the crop factor 1.6 for canon to find what the depth of field will be. The light coming in will remain the same.
 
First of all, the "Crop factor" has nothing to do with aperture, so f2.8 is f2.8 is f2.8.

John, the way crop-factor gets hooked into aperture is via depth of field calculations. It's technically based on the photographer's behavior.

For purposes of calculating exposure, f/2.8 is f/2.8 is f/2.8. For purposes of calculating how much depth of field you get, there's a nuance where you multiply the focal ratio by the crop factor. But again... that's based on the presumption that a photographer will change their subject distance when using a crop-factor camera vs. a full-frame camera (assuming the same lens focal length).

E.g. if you wanted to compose the frame for a certain physical size (say it's head & shoulders portrait). With a full-frame camera you'd stand at some distance to get that composition. With a crop-frame camera you'd stand a bit farther away to get the same composition. When you step farther away to achieve the composition, the DoF increased and that means the amount of background blur decreased.

How much did the blur decrease? It turns out... mathematically if you multiply the aperture by the crop-factor... you get the same DoF.

E.g. if I got a certain amount of blur at 200mm & f/2.8 with a full frame camera, then use that same 200mm & f/2.8 with a crop-frame camera then the blur is reduced. The reduced blur in the crop-frame camera at f/2.8 will match what a full-frame lens would have done if I multiplied the true focal ratio by the crop-factor (in this case, f/2.8 x 1.6 = f/4.5).

Here's a YouTube video that demonstrates how it works (with real photos):

Thanks for replying to that! That's the same video I was thinking about too!
 
This has been a bug of mine for a while.
The 70-200 on a DX/crop camera is a bit too long on the short end. You can always crop into a pix, but you can't get more than what the camera took. And this class of lens went from 80-200 to 70-200, so the short end got shorter to give a wider view. Put it on a DX/crop body and you go narrower.
The old Sigma 50-150 was a DX version of the 70-200, but then Sigma discontinued it. A smaller/lighter version 2 of the VR model would have been a GREAT lens.
The current Sigma 50-100 gives up the extra 50mm on the long end for a wider aperture. Is the wider aperture worth the loss in focal length? Not for me. It seems to be more a specialty lens.
The lack of a GOOD DX/crop equivalent to the 70-200 is what is pushing me to go up to FX/FF.
 
Indoors on 1.5x, like for basketball,volleyball,even wrestling and gymnastics, a 70-200 sucks...it's too damned LONG on a crop--frame body.

This issue with Sigma has long,long,long been poor autofocusing on some examples of their lenses...with some camera models.

When the camera makers update their AF protocols, the third-party lens makers have to reverse-engineer their lenses for the newer cameras; this is usually a fairly uncommon, rare occurrence, but say like, when the D200 came out and consumer Nikon's got back-button focus, Sigma's older lenses were suddenly, in many cases, not working right. Honestly...I got rid of my two big, high-end late 1990's Sigmas because my 2005-and-newer Nikons didn't focus "right" with them...wayyyy too many instances of severe focus hunts with the HSM EX-series 180/3.5 APO-Macro and the EX-series HSM 100-300mm f/4.

I LOVED the Nikon 50-135mm f/3.5 Ai-S Nikkor manual focus on the D1,D1h,and D2x crop-frame d-slrs...the 50-135mm range was SUPER-handy!!! There is simply no comparison between the handiness of a 50-135 and a 70-200 or 80-200 on a crop-frame body; the shorter lens makes a HUGE difference in usefulness. So,so,soooooo much better for parades, events, and portraits/scenics, with the 50mm versus 70mm short end.

Now that we've gone up to 24-MP on APS-C...there's less need for the 200mm top end all of the time, but for longer-range stuff, 200mm is better than 135mm was, and much longer than 100mm is.
 
... The amount of light coming into the lens and hitting the sensor will be the same on both full frame and crop at the same aperture but on crop the depth of field won't be as narrow as on full frame at the same aperture. To find out what aperture it's equivalent to you have to multiply the aperture by the crop factor 1.6 for canon to find what the depth of field will be. The light coming in will remain the same.
As I said: Crop factor has nothing to do with aperture. While there is a difference in DoF, it relates to the size of the sensor, and is not a straight "1.6 greater".
 
What's your budget ?? ... that's usually most people's limiting factor.
Well I can't get both! :) but around $1,000 the sigma is $1,099 and I can find a used 70-200 f2.8 for around $999
Problem is their focal lengths are different.
So what is you main focal length that you shoot at ?

You'll have to have some give and take based upon how you shoot, or can shoot in certain situations. Maybe you get one lens now, and the other later.
 

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