Hi
Was wondering in terms of astrophotography, how much difference is there between the Canon L series lenses and a refractor ? I'm mainly looking at the 70-200mm F4 IS lens in comparison to ED80/ED100?
If they are very similar might opt for Canon lenses, can serve dual purpose for me in terms of photography
Although can't use the Canon lens as a refractor (unfortunately)
Your help would be greatly appreciated thanks.