Can any of you nice people out there help me with my conundrum please? I have a Canon Mkii 100-400 which IMO is a superb lens in most respects. It's been the only lens of my collection so far that I haven't even considered letting go but over the past few weeks I have started to struggle little with weight. Camera equipment that is, not my own. I used to have a 400 f5.6 many years ago which I let go and after looking through my catalogue of images very often top shots with that 400 appear with regard to BIF, and very nice they are too, even when compared to BIF with the Mkii which although is obviously a zoom, is used most often at 400mm. I'm tempted to sell the 100-400 Mkii and re-aquire the 400 f5.6 and bank the financial saving. Yes I know there is no IS on the 400 but TBH it's mostly turned off for my birding shots on the 100-400. The loss in weight would be considerable not to mention the gain in my bank account as a 400 f5.6 can be had for a muchly reduced cost. But would I be disappointed in the IQ?
Sensible input would be appreciated, especially from those members who have or have had both of the above lenses.