I have tried IRFANVIEW but have just found another option which seems to work OK, and considering the time that it saves is probably the way that I will go which is Photobot. Just set up a folder to drop your photos in and it processes them all automatically! The website is
The world's first Zero-Click™ picture correction software! and you can download the full program for free and try it with 100 images before needing to purchase for just $29.95.