In the Second Life Viewer

1. Go to Edit -> Preferences -> Graphics and then move the bar for "quality and performance" to "High" or even "Ultra" if your graphics card allows it.
2. Tick the "custom" tickbox to get more options. Try sliding the "Draw Distance" higher to see further.
3. Enable the "Advanced" menu with Ctrl/Alt/D on Windows systems, on a Mac use Cmd/Opt/Shift/D;
4. Select Advanced -> Disable Camera Constraints to disable camera constraints and allow the camera to be drawn back further;
5. Select Advanced -> High-res Snapshot to get higher resolution snapshots.