With a lot of light well, but overall not very satisfactory

I've been using so far the Tamron SP70-300 F / 4-5.6 Di USD for Sony SLT-A57 as a pillar for motorsport events and
other applications where large focal length is required.
In principle, I am satisfied, but unfortunately also 300 mm lately are increasingly to become "short".
A bigger push must be found and after a long argument with my reason I've ordered the 50-500 Sigma.
Its sister model, Sigma 150-500 mm OS HSM Lens F5,0-6,3 DG is indeed much cheaper,
However, my initial focal length of 150 mm to "long" and the objective is therefore too inflexible for me.
Alternatively, I have also on the highly acclaimed Sony 70-400mm G SSM his eye -
Read more under the heading: "A good advice for SONY-user".

--- --- INITIAL CONTACT

The Sigma comes in a roomy, padded case, with this are a lens hood
including overtime, a filter diameter Reducing ring, a wrist strap and the compulsory
Front and rear lid.
At first glance, the lens works quality, the matt surface looks chic and is also
tacky feel. The processing makes a solid impression, even when fully extended nothing wobbles.
Both zoom and focus ring can be rotated equally supple and well dosed - Best!

Both with and without bolt-camera can be the lens carefree on the generous
make-sized tripod collar, without fear that the good piece rolled off the table - Virtually!
Then follow the first test photos and after a few shots freehand makes the high
Weighing almost 2 kg thanks to a pull in his left arm felt and I realize that longer sessions
could draw a nice muscle soreness after without monopod. ;)
Well, for lack of strength in the arm, the lens can nix!

--- --- PERFORMANCE

THE FOCUS IS SITTING
Sigma's HSM drive provides quiet and fast focusing, the focus is good but not perfectly adjusted,
the slight deviation in the low single-digit millimeter range is tolerable.
So far so good.

ALL GOOD IN THE MIDDLE zoom range
First test photos at moderate lighting conditions fall out positive. At 300 mm sizable Photos
dimmed slightly better, but in direct comparison at 300 mm it does not quite reach the edge of the Tamron.
Colours and contrast give no cause for criticism, fall neither positive nor negative on.
The built-in stabilizer ensures a quiet viewfinder, because I had a Sony-users to get used to,
but a quiet Sucherbildhat already its appeal. ;)

STROLL ALONG IT IS SOFT
Fully extended at 400-500 mm, the images are increasingly softer. The details appear slightly washed out,
the contrast decreases. Fade somewhat improved the quality, but makes handling by the
anyway a little tricky if ISO and / or exposure time to rise even small light intensity rapidly.
If the lighting conditions are poor, the Sigma comes to its limits. In my tests on
Late afternoon in dwindling light with 400 mm and maximum aperture was the reject rate
at frightening 100%. Invariably blurred and practically useless all images.
Before me now assumed that in these conditions fails, any other objective,
as I point out that I have repeated the test with the Sony 70-400mm G SSM following while
each photo has become clearly focused. But may also works with the Sigma Sony cameras
just not as well put together as the lenses of our own production.

--- A good advice for SONY USERS ---

Who telephoto beyond the 300 mm looking for his Sony camera and is ready to take the price of the
To lay Sigma 50-500 on the counter, you should rather drauflegen something and for Sony 70-400mm G SSM
grab. I can compare the two lenses together with the conclusion that the Sony
in terms of imaging performance plays in a different league and the Sigma in the image quality
is superior in every way. (The Tamron too)
How that looks at home Canon or Nikon lenses with comparable, I can not judge,
perhaps someone else a hint Make a comment.

--- --- CONCLUSION

Who needs absolutely 500 mm and mostly photographed in very bright light, is the 50-500
Sigma certainly have his joy. The wide zoom range makes it ideal for all kinds
although the heavy weight restricts the freedom of movement somewhat. For allow processing and haptics
nothing to be desired.
I felt the power at 400-500 mm most importantly, the weaknesses at the long end especially at full aperture and
bad light were me then but too large and significantly improved image quality of the Sony 70-400mm G SSM
too convincing, so the Sigma is unfortunately back.

When scoring I'm a little torn and vacillate 3-4 stars.
But because I can not assign 3.5 stars, I opt for 3 stars because the optical power
well behind the much cheaper Tamron SP70-300 remains and a large focal length range
alone no top rating justifies.