I can see what you were trying to achieve with this shot and CT's edit does alot to improve (as per usual
) However, I feel compositionaly it's a little off kilter. It would sit easier on the eye if....
a) either the foreground or sky was more dominant. At the moment there is nothing to draw your eye into the shot and there is no foreground interest. Tipping the camera down a few degrees would've made the crops more a feature, as would lowering the viewpoint slightly to around the height of the heads of the crops. If you get an opportunity like this, it's worth shooting as many different angles as you can, it's all to easy to get caught in the trap of taking everything from head height.
b) Another option may have been to zoom into the shot more, distributing the balance so it's 1/3rd each sky/hedge/foreground.
c) finally, placing the sun slightly off centre may have added impact to the scene.
As I said above, when you have a subject that's as potentialy brilliant as this one, it may just be worth filling the memory card with different angles etc. You only need one shot to be perfect out of 250 odd!
As for noise, It's really not a problem in this shot, no worse than any grain you would've had from 100asa c41 film! If you want to minimise it in future, shoot at the lowest possible ISO setting, use a tripod and expose the shot so the histogram is pushed as far to the right as possible without blowing the highlights, you can then pull the exposure back in RAW without creating more noise. If you go the other way and expose with the histogram to the left, when you push the exposure in RAW by increasing the exposure, you'll also increase the noise.
I use a camera with a VERY noisy sensor, the setting I tend to use in NR is colour NR @ 100% and luminance at about 35-45%, sharpening turned off, then correct the sharpening through USM in CS2!
A bit long winded but I hope some of the above helps.
Above all else, break some rules and bear in mind this is only one persons opinion!
