I put my 100-400 f5.6L together with my M50 - shot some pics of the sun (thru 19 stops of neutral density of course) - it worked just fine - here is a link to a) the rig, and b) one of the shots i took at 800 mm (1260 considering the crop factor)
First off - let me say - I do NOT condone violence of any sort ... and let it be known that no photographers were harmed in the making of this pic ... yup - it's a self portrait! what else can we do while quarantined :) I found a tutorial on how to make these shots - it was quite illuminating (literally) and I had a lot of fun doing it! thanks for looking!
Pics of Vancouver don't do this beautiful city justice ... yet we'll keep on trying :) left my abode whilst still dark - arrived at quay still in the dark (sort of) ... sun rising in the east (this pic is looking south westish at about 7:55ish - 10 stop ND filter for 51 seconds to capture the reflections in the water and on the edges of them beautiful buildings :) ... the dl is pretty cool :)
I purchased a filter holder that flips up and away that holds my ND filters instead of screwing them in and out directly from the lens - which (as we all know) leads to 'not-so-perfect' focus on some long-exposure shots. so - attached them to my 24-70 screwed in to my M50 and took a couple shots down at our local inland man-made lake (aka LaFarge Lake) - 30 sec at f8 :)
My fam contributed towards the mirrorless M50 for my birthday the other day - I purchased the Commlite CM-EF-EOS M Electronic Auto-Focus Lens Mount Adapter-(EF-M Mount) Mirrorless Camera Body Adapter for Canon - and attached my 24-70 F2.8L lens to the M50 to shoot the bridge that I cross daily on my commute to work - gotta say I am loving the setup - it's not like my 5D Mk2 - but still get great results :)
it seems like we are being invaded - but I can't help feeling an affinity for these visually stimulating plants ... as a youngster we would blow off all the dandelion seeds and make a wish - the more seeds flying off the greater the chances of the wish coming true :) - 'wish' I could remember what we wished for!!!