Many thanks to you all for your help with this, I can't believe what a massive improvement you have been able to make to the photo. This young man looks so distinguished and determined for a lad of no more than 21. Fortunately he survived the war. Having recently recovered his war medal (thanks to a contributor to Roots Chat!) I can now mount it with a fitting photo!
Thanks again!
PS Special thanks to Carol for suggesting I post it here!