UPDATED: This is how much smaller the Olympus 300mm lens is compared to the Canon/Nikon version.

43rumros Steve sent me that picture from the Photo Festa 2014. You see the Olympus 300mm f/4.0 size compared to the [shoplink 48604 ebay]Canon (here on eBay)[/shoplink] and [shoplink 48605 ebay]Nikon (here on eBay)[/shoplink] lenses. That’s the price and size you pay for Full Frame lenses :)

And also DC.watch posted some pics of the event. So here they are:

UPDATE: I corrected the ebay links ot the Canon and Nikon 600mm (and not 300mm) lenses.