# What exactly is the M50 crop in 4k? With a 0.71 reducer?



## Plucas (Sep 5, 2018)

Hi,

The articles I've read suggest different crop factors on the M50 in 4k.

With no digital IS, what would it be?

And what would it be with a 0.71x speedbooster?


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## mensaf (Sep 9, 2018)

It's about 2.6 in 4k and drops down to about 1.8 with the speedbooster. I have one of those custom ones and it's pretty dang neat-o. I wouldn't use the 4k unless I were shooting manual (focus peaking ftw) and either moving slowly or not at all. Lots of rolling shutter. That being said, I love the way it looks, but I can't do much with it unless I'm doing an interview or just some b-roll.


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## Plucas (Sep 11, 2018)

2.6! That's interesting. Andrew Reid, in his article on the M50 as a Digital Bolex says the crop is 2.34x while Dave Altizer said it was around about 2.45x.

Yes, the use of the 4k is limited mainly to interviews or slow pans.

I wonder if someone, like the engineer in South Korea who made the EF-M EF speedbooster, would like to also create an EF-R to EF one with a 0.71x reducer. That would reduce the 1.8x crop to something more usable (albeit you would have no access to the EF-R lenses).


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## mensaf (Sep 11, 2018)

It's a 1.6x crop and then I think something a little below a 1.7x crop when it's in 4k. It turns the wide lens into something absurd. Outside of that, it's not really an issue truth be told.


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