Sigma 150-600mm C Help Please

[mant01]

Im have an issue with soft focus and although its probably bad technique as Im new to the lens I thought Id ask. At 600mm at around minimum focus distance I get nice detail but even by stepping back 20ft or even less Im getting soft images. The first image is as close as i could get and focus, taken at 1/320s and the 2nd soft image is between 15-20ft at 1/1000s, both shot at F8, 800iso. Im just sure why its getting so soft so quickly especially with the 2nd being shot at a higher speed, both are straight from the camera, thanks for any help.

 

[wave01]

did you use a tripod

 

[GreenNinja67]

Are you sure the ISO's the same in each image?

The bottom one is noisy compared to the first.

Also regardless of the distance the exposure should be the same. Sounds like the second one is underexposed, possibly causing the noise which will also affect sharpness.

 

[mikew]

The second one must be a crop then was the first one, i would like to see what they where cropped from.

 

[mant01]

No tripod were used in either image. The ISO is the exact same but the second has a stronger crop which will show the noise more, the light was also shifting quite a lot. Even though the 2nd has a stronger crop the first cropped to 100% is still much much sharper.

 

[mant01]

Here are the original images and also a 100% crop to compare. Thanks



100%


Soft original


100%

 

[the black fox]

There are to many variables in it to come to a result ,as a long term user of the sport version,I can state that I simply cannot get two identically sharp shots on3 after the other . With these lenses there is a fair degree of compromise in it which you have to accept ,it might ? Be that you need to do a micro adjust on the long end of your focus range ,it might also be the fact that your using a living target and while the camera and lens is tripod mounted your target might have moved slightly, you really need to set up a similar test with a static target and work out any issues from there.
Just noticed you haven’t used a tripod. That’s probably the problem in this case even as little wobble at your camera end is amplified at the lens end