How do you plan to use the lens? Do you have a heavy tripod and Wimberly type head? You will definitely need it for an 800mm lens. My Sigma 300-800 is a heavy beast.
For wildlife I think the 500 is a better choice. That's what I would choose if I could only have one.
Not wildlife....
A cattle egret shot at 731mm with a 1DsMkII in December 2006
If you intend to put such a lens to extensive use, despite some of the practical issues associated with its use (weight / support needed /7m mfd etc) and really make use of its reach ... almost to the exclusion of other types of setups / subjects ... then its probably a 'goer' ... otherwise it'll end up being a 'hanger queen*' imo
Using a 500 is something of a 'production /effort' in itself ...but its one I've got used to... one of these would -imo - require even more dedication to its use, certainly to make it worth the expenditure.
I have the 500mm Sigma prime F4.5 ... after years of Canon I've adapted it now to Sony A series mirrorless. I boost it by 2x in-camera or 1.4x extender, and on a crop sensor it's another 1.5x -- Sharp lens. And conveniently packs into a backpack / carryon.. Smaller Gitzu tripod and gimbal -- not easily handheld. Strictly wildlife. I'd buy it again vs 800mm.
I had the 500mm F4.5 HSM for years - last spring I thought I would get it cleaned and Sigma said they would no longer work on it. They would work on the newer DG version but not on the previous version. Now I have both the 150-600mm sport and the contemporary. Both will match the old 500mm at 5.6. At f8 the 500mm might be a touch sharper than the C. The sport is, I believe better and is 600mm. The 500mm at 4.5 was a bit flat - lacking in contrast compared to anything newer. If you need f4.5 then go for it. If not the current zooms are hard to beat and have vibration reduction.
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For wildlife I think the 500 is a better choice. That's what I would choose if I could only have one.
Not wildlife....
A cattle egret shot at 731mm with a 1DsMkII in December 2006
Moderator of the Technique Forum and Finishing School on Dgrin
I'd agree with this question.
If you intend to put such a lens to extensive use, despite some of the practical issues associated with its use (weight / support needed /7m mfd etc) and really make use of its reach ... almost to the exclusion of other types of setups / subjects ... then its probably a 'goer' ... otherwise it'll end up being a 'hanger queen*' imo
Using a 500 is something of a 'production /effort' in itself ...but its one I've got used to... one of these would -imo - require even more dedication to its use, certainly to make it worth the expenditure.
pp
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