There has been some fair critism of the way I took the test crops shown earlier in this thread so taking this on board I decided to have another go at this comparison but in much more controlled conditions...Indoors using flash and keeping the framing exactly the same by moving the camera closer or further from the test target...And just to spice it up a bit I decided to test two other 50mm lenses at the same time.
The comparison crops were pasted together on photoshop and text added. The Auto colour tool was used on most of the f2.8 crops as the camera had metering issues with the onboard flash at that aperture and you can see the result of this with text on the gas canister looking orange instead of red as it should be.
I added +20 contrast to every crop whilst also reducing the brightness of each crop by -10 but thats the total amount of processing done to the images.
I used Irfanview to crop the original test images and to resize the test sample pic.
Here are the results:
