Nice job!
Did you use a tripod to steady the camera?
Another thing that helps reduce blur is to use the timer to trip the shutter...so you don't shake the camera when you push the button, etc.
The autofucus on most automatic cameras can fix on the "wrong thing" shooting beam shots, so some parts of the pic are blurrier
If anything is sharp...that's where the focus was, in case you need to adjust your aim, and...if NOTHING is sharp...it might have been aimed over all the targets (Infinity), leaving the foreground and targets blurry, etc.
When you do the shots, write down what you can see...which LOOKED brighter, which illuminated the broadest patch, and so forth. Use landmarks/reference points in your notes:
Examples:
Control - Pitch black, can't see anything out there at all...or, too dim to make out anything but silhouette of combine, etc.
5.11 at Combine - Discharge pipe over body dimly lit along body length, not visible to rear of body. Cab barely visible. Patch on ground illuminated on way out to combine, but doesn't reach combine, light might be aimed low, or, out of range. No lighting under rig.
M20 Combine - Hot spot centered on rig. Hopper and discharge pipe are visible, but cab and rear of body are dim to not visible (Can't see discharge pipe past the rear of the rig body). Light extends to beneath the rig, illumination of row of corn behind it viewed from underneath, but not to sides. Very dim illumination of ground on way out to the rig, light is concentrated on the rig itself. Rig visibly brighter than 5.11, ground is visibly darker. Fore/aft of tires are dark.
980L Combine - All of cab, hopper and discharge pipe are visible. Ground on way out to rig is illuminated, and continues beneath truck to corn row behind it. Some of corn row to rear of rig is visible, but not past end of unloader pipe. Fore/aft of tires are lit, and part of the thresher mount, but the thresher reel is dark. Rig and ground are visibly brighter than M20.
(I just made up the above as an example of what you might have written down if the pics are representative of what you actually were able to see that night. I last worked for a farmer maybe back ~ 1969 or so, so forgive me if the combine parts are not accurate
)
Obviously, you'd write down and describe what you saw that night...w/o seeing how the pics came out. That way, you will KNOW if you are showing what you saw that night, and if its representative. Its, IMHO, the best way to show what a light's beam looks like for those trying to get a feel for the difference in beam patterns, etc.
For example, while the M20 is putting a brighter light on the rig than the 5.11, your pic shows that the M20 is only illuminating a small circle, and not much to the sides or on the way out to your target....and that its still dimmer than the 980L on target, but that the 980L is lighting up stuff on the way out to the target, as well as a little to the sides as a bonus, and so forth.
If I am trying to decide if I want to upgrade my M20 to a 980L, this would convince me if I wanted that beam pattern. If you over exposed the 980L, so it only LOOKED like it was brighter in the posted pics...well, I'd be fooled, and sell my M20 for the wrong reasons...and then come looking for you to take out my frustrations.
So, a simple set of notes the night you shoot the beamshots acts as a quality control for you...so you can feel confident that your shots show what YOU saw at least that night.