jcs

The term 'equivalence' is just a tool to match cameras and lenses, not lenses by themselves. Once the concept is understood, sure, for stills you can use shutter, ND, and ISO as needed to match EV (for film/video need to match shutter).

That's right especially if you're doing it wrong and you know it!  

Mattias, you are so close, if you set ISO correctly you've got equivalence down.
What's the purpose of your videos? Is it to create drama or controversy to get views and negative engagement by doing things wrong on purpose, or is it to share your work, to help people make decisions and to help them learn how to shoot? Why not demonstrate equivalence correctly so other people can learn too?

I am going to start that next, just do not have the time right now.
"TV" is the new cinema, it seems like everybody does episodes for something. It is a great medium to tell stories that can exceed the 90-120 minutes of an average movie, while the budget (in the good ones) are still there (Westworld, The man in the high castle, The expanse - which season 2 plays right now, etc etc) and through the new technologies, the audience is the whole world, mostly instantly.
Taboo was the last good one I watched recently, didn't deliver 100%, but technically was awesome and I liked the rhythm and the acting, scipt-wise there were a few black holes, but overall it was a very good experience.

I think good TV has surpassed movies in 90% of the cases. when you count the quality vs. speed vs budget is incredible what the teams can achieve. A lot of them would look great on a big screen. IntoTB is a great show and I'm looking forward for the new season!

I just finished watching the first season of Taboo and I am surprised how much cinematography is going into these new shows. TV are almost exceeding movies nowadays. 

An example of excellent RED skintones and overall color. Not up to ARRI (especially highlights), however very saturated pleasing color that works well for the story. If you're into martial arts in a dystopian future with excellent acting (for the most part :)), great camera work, and cool music, check it out. Shane Hurlburt is DP; he also sells tutorials based on camera/lighting for the show.
Warning: don't start watching if you have anything important to do, it's pretty awesome!  

Sorry Mental Lapsus, it's a two stop jump like you said,when I read 4x I thought you ment jumping 4 stops. Anyone who does't get the equivalence thing might just compare a m43 and Fullframe camera in DXO charts, check the dynamic range chart.  

In the video you stated 'equivalence', which means you try to set both cameras to match per the equivalence math, right? Are you saying that the full frame camera you used couldn't set the ISO ~4x what you set the M43 camera? What were the two cameras?

Referring to the Equivalence test here at 4:02: 
For example, if the crop factor is 2 and the ISO for the crop camera is 800, the FF camera should be set to 2^2 = 4*800 = ISO 3200. That's why the full frame image is darker.
Mattias states he doesn't believe in equivalence (including in the video), then does the test wrong- what's the point?

The difference between hard and soft lighting is simple: diffusion, or not, and how much (shadow edges hard or soft/diffuse). A point light source is a perfect hard light with little or no visible diffusion: very crisp shadow edges. Being inside a glowing perfect sphere is perfect diffusion (actually, if the sphere was filled with glowing plasma, that would eliminate all shadows :)). A formula: a single point source is hard, add more sources to get more diffusion (or bounce/shoot-through (fabric etc.) to make a larger source, also known as increasing light wrap. http://www.canvaspress.com/focal-point/article/2014/06/19/hard-light-vs-soft-light/

I have different systems BECAUSE they are different.
I didn't buy them to try and get the same result and often use the SAME lenses across systems as it saves me buying more lenses.
  That said, IF there is a lens available, then you can match them all else being equal***
Trouble is, there are no 12mm f0.7 M4/3 lenses that would be needed to match a 24 1.4 lens FF or 42.5mm f0.6 M4/3 lens you would need to match an 85 1.2 FF.     You would probably need to be shooting in something besides air to be able to match a FF f0.95 lens with M4/3 (though an f0.5 lens would get close).      Using focal reducers with the fastest lenses doesn't get you any benefit in speed either as there seems to be limits.
https://en.wikipedia.org/wiki/Lens_speed#Fast_lenses
If you have a faster medium format lens, the same also applies against FF but again, apart from some rare and expensive mostly aerial lenses, that isn't going to be available and wide angle lenses in particular are not going to be (easily) matched (let alone beaten) by what is available for FF.       For me, "equivalence" favours smaller formats for telephoto use (as long as it is "good enough").
*** The day M4/3 can match my A7s in low light/high ISO is likely still quite a way off though wouldn't it be nice to see and of course by then FF low light cameras will be better still.
The Government does create jobs!

Please. No-one is denying that there are combo's that you cannot match in practice (as in your example), when very large differences in sensor size are involved. But this is only due to the fact there are no equivalent lenses (Iphone 6 cropfactor 7.21, you can do the math...or can you?).
However, the overlap between say medium format and fullframe is much less extreme and yes, can easily be matched using equivalent lenses.

I actually did a shoot the other day and got almost the exact same shot of a girl on a D750 w/ Voigtlander 58mm 1.4 and a RZ67 w/ 110mm 2.8 and FP4, a minute or so apart. I'll dig them out and post later. 

Yeah if you study the greats in film making they use a lot of camera angles we really can't even afford to do. They are masters of isolation. Having views in films you are not accustomed to, I think, keeps you glued to the seat to see something you have never seen before in a sense. Sort of the unknown , and humans are in reality, a curious breed.
Plus lets face it, they have the best of the best on every high dollar film, using 35mm, Panavision, CinemaScope,70mm, etc from script writing, acting, acquisition, best DP, lighting equipment from hell, best focus pullers, and editing, not counting top notch audio, you name it, and a 50 piece Symphony Orchestra. Hard to go wrong with that. "We should be so lucky" as they say.
But I guess even with all that, more stuff probably bombs than makes 300 million bucks. So don't feel bad if your efforts, at times, does not come out so hot. 

While I've seen RED and Sony content that looks great and with excellent skintones, many times the color and highlights don't look very good (looked up on IMDB etc. to see what camera was used). ARRI just looks more pleasing, and I figure that it's also creating footage that's easier to make look good with less effort. For what we do (pretty basic stuff at this point), the C300 II does everything we need including creating skintones that need little or no work in post when lit well. The A7S II for example can also do good skintones, but needs work in post. I think ARRI's experience with digital film scanners has given them great insight into building a camera system that produces film-like capture which ends up being very easy to make look good in post, and thus why most of the ARRI content looks really good. Guessing that ARRI will announce a true 4K(+) (Super35) camera at NAB.

Here's a basic formula:
When possible, take away all the light and carefully add light tuned for the story and emotion of the scene. Look at how often everything is dark, or overall not very bright in classic films. Paint with light. There are tons of books on this subject. Shoot at night and wet down the street. Set the frame rate to 24 (or 23.976), shutter 1/48 (or 1/50). That's for normal shots, you can go all over the place for emotional effect of the scene. Protect highlights so they don't clip and pay careful attention to exposure to keep skin tones in the sweet spot for your camera. Study film behavior for highlights and adjust your look in post to match the highlight and color response of film. Film generally never gets super white. Use a diffusion filter of some kind. Blur a little in post if necessary and add full resolution film grain (blur may not be needed if diffusion is used). Make sure there are no digital artifacts such as aliasing or Moire. Use depth of field to help tell the story by helping the viewer focus on what's important in the scene. If your camera has rolling shutter, make sure to move the camera in a way to minimize it. Try to make the scene a little 'unreal', in a way you would not see in normal everyday life. Like in a dream.

Here's a basic formula:
When possible, take away all the light and carefully add light tuned for the story and emotion of the scene. Look at how often everything is dark, or overall not very bright in classic films. Paint with light. There are tons of books on this subject. Shoot at night and wet down the street. Set the frame rate to 24 (or 23.976), shutter 1/48 (or 1/50). That's for normal shots, you can go all over the place for emotional effect of the scene. Protect highlights so they don't clip and pay careful attention to exposure to keep skin tones in the sweet spot for your camera. Study film behavior for highlights and adjust your look in post to match the highlight and color response of film. Film generally never gets super white. Use a diffusion filter of some kind. Blur a little in post if necessary and add full resolution film grain (blur may not be needed if diffusion is used). Make sure there are no digital artifacts such as aliasing or Moire. Use depth of field to help tell the story by helping the viewer focus on what's important in the scene. If your camera has rolling shutter, make sure to move the camera in a way to minimize it. Try to make the scene a little 'unreal', in a way you would not see in normal everyday life. Like in a dream.

Yes jcs lens choose is essential for a cinematic look, most movies are shot digital now unless you are Christopher Nolan or Tarentino , the fact that all these films shot digital look cinematic shows its the cinematographers craft not the camera , also note the Arri Alexa is not a 4k camera yet its become the industry standard over the past 5 years , delivery and acquisition over the past year has altered for platforms like Netflix who now require 4k acquisition and work flow ,so some of these shows are now shot on RED Epic Dragon and Weapon cameras giving RED a new share of the market share from the Arri 

12. Use FOV/focal length for dramatic effect: a wide angle lens up close to the actor is distorted and 'crazy', a long lens from far away to give compressed isolation, etc.

Here's a basic formula:
When possible, take away all the light and carefully add light tuned for the story and emotion of the scene. Look at how often everything is dark, or overall not very bright in classic films. Paint with light. There are tons of books on this subject. Shoot at night and wet down the street. Set the frame rate to 24 (or 23.976), shutter 1/48 (or 1/50). That's for normal shots, you can go all over the place for emotional effect of the scene. Protect highlights so they don't clip and pay careful attention to exposure to keep skin tones in the sweet spot for your camera. Study film behavior for highlights and adjust your look in post to match the highlight and color response of film. Film generally never gets super white. Use a diffusion filter of some kind. Blur a little in post if necessary and add full resolution film grain (blur may not be needed if diffusion is used). Make sure there are no digital artifacts such as aliasing or Moire. Use depth of field to help tell the story by helping the viewer focus on what's important in the scene. If your camera has rolling shutter, make sure to move the camera in a way to minimize it. Try to make the scene a little 'unreal', in a way you would not see in normal everyday life. Like in a dream.

I will make a comparison, nikon d800 50mm 1.2@1.8 vs mamiya 645 80 1.9@ 2.8 vs mamiya rz67 90mm 3.5@3.5 which is roughly equivalent. I will use some cheap black and white film unless someone wants to buy me some portra 400 or ektar 100 (sharper) for this crap :P
Btw, the equivalences don't have to be exact, because if the difference is so tiny it could be adressed to some minor equivalence differences, then there is no difference between formats. The fact is, I use 6x7 because I can't take the same picture with the nikon, trust me, I fucking hate developing and scanning neither do I like lugging around a gigantic camera plus lenses and attracting views from people, I don't buy the whole romantic point of view about film, I just enjoy the endresult.

Do the experiment properly and you'll find that the perspective is the same.  Surely you must have heard countless times before that perspective depends only on the subject distance.  This is a truth that you shouldn't ignore.  More precisely, perspective depends on the distance from the subject to the entrance pupil of the lens.  For this reason, the entrance pupil is sometimes called the center of perspective.  I suppose you could call it the "point of the wedge" in your language.  FYI, technically, the entrance pupil is the image of the aperture stop as seen from the front of the lens.  So, in your experiment, just put the entrance pupil of both the 24mm and 36mm lenses at 10 feet from the subject, and the perspective will be precisely the same.  There are some easy techniques for finding the entrance pupil location with an accuracy of about +/-1mm that stitched panorama shooters use all the time - if you need help just ask.
The subject-to-image plane distance is not what matters.  Its the subject-to-entrance pupil distance that does.  So, this notion that full frame will be "further inside of the wedge than in the APS-C format" is just another way of saying:  "oops, I goofed, and didn't keep the subject distance constant".

"Right -- it becomes a 56mm FF lens, with the properties of an 80mm lens on MF."
No, it becomes a 56mm lens.
Adding the speedbooster changes the lens, not the camera.        Some lenses are designed by using a focal reducer internally I understand.     All you are doing here is adding it externally.
 
"Why not just design a simpler lens with the desired focal length -- without any focal reduction stage?"
Perhaps he should.    Maybe something like the Coastal Optics 60mm for instance?   Oh wait, he did??

Here's a basic formula:
When possible, take away all the light and carefully add light tuned for the story and emotion of the scene. Look at how often everything is dark, or overall not very bright in classic films. Paint with light. There are tons of books on this subject. Shoot at night and wet down the street. Set the frame rate to 24 (or 23.976), shutter 1/48 (or 1/50). That's for normal shots, you can go all over the place for emotional effect of the scene. Protect highlights so they don't clip and pay careful attention to exposure to keep skin tones in the sweet spot for your camera. Study film behavior for highlights and adjust your look in post to match the highlight and color response of film. Film generally never gets super white. Use a diffusion filter of some kind. Blur a little in post if necessary and add full resolution film grain (blur may not be needed if diffusion is used). Make sure there are no digital artifacts such as aliasing or Moire. Use depth of field to help tell the story by helping the viewer focus on what's important in the scene. If your camera has rolling shutter, make sure to move the camera in a way to minimize it. Try to make the scene a little 'unreal', in a way you would not see in normal everyday life. Like in a dream.