View attachment 8255 I i bought a set of neewer rings to test stacking 2 2x canon converters with my sigma 100-400 i used the 21mm which the test shots worked out fine but while resting on my table the 21 mm fell apart due to plastic failure while mounted, i expect the weight of the sigma and 2 teleconverters was a bit much for it. i will now get the proper canon one/s to use the 31mm did not lock in place, just a lesson, you get what you pay for.
I would agree and suggest the weight is a bit heavy for a piece of simple plastic. That lens is a pretty big lens did it not come with a tripod collar for it? Makes me wonder if the cheap extender would even support the body hanging behind it with lens mounted to the tripod.
the siggy 100-400 is the lightest of the 400 zooms it doesn't need a tripod collar, i have been hand holding it pretty much ok, funny how what seened like a huge lens suddenly became a baby when i took both the converters off. when i got the ef adapter i got a tripod mount on that because i knew i would need a tipod for it once i started adding stupid mag to it i use the rapid black strap connected to the ef adapter ring so neither the camera or the lens is taking the weight of the other. the two canon teleconverters make to whole assembly "weighty'. the aim is to have something ready for Saturn in the summer when its not so close to the sun i'll be testing it out on the moon with the 2 converters to see how bad the refraction etc is, the daylight test was pretty good, plenty of light so it would easily take a 3rd x2 light wise. i dont have any plans for using the x2 converters on wildlife unless John Cleese has been there first..............(python ref)
