tupp

I am ignorant of C-stand weight ratings, but I doubt that there is much difference in weight capacity between a plain C-stand and a C-stand with the typical "Rocky Mountain" leg.

On the other hand, one should never get even close to loading stands to their rated capacity.  Putting too much of a load on a C-stand might not end well (nor will it start well if the grip arm gets bent).  If one is not sure the stand can take the load, use a bigger, stronger stand.
 

Thank you for all the excellent info. Really appreciate it. 
One more quick question if I may...
I know there are C-Stands with sliding big legs (to deal with things like stairs or uneven ground) and then stands without a sliding leg. Is either one "stronger"? Meaning, if someone gets a C-Stand with a sliding leg, will it be rated for less weight than a stand with a non-sliding big leg?
Thanks in advance.

Yes, set electricians (but rarely the gaffer) arm-out lights from C-stands.  There are three common methods for arming-out with a C-stand:
Mount the item on the grip arm and extend the arm "righty-tighty;" "Cantilever" the grip arm with a ratchet strap or a trucker's hitch; Boom the grip arm, using a sand bag as a counter weight.  
It depends on the size of the stand and the load to be armed-out.  A junior/combo stand will be capable of a larger footprint than a C-stand, and they are much stronger than a C-stand.  A typical baby stand might not be as good as a C-stand for this purpose.
 
There are countless ways to arm-out a light, and there are many booms and cantilevers designed especially to do so.  It's a large and involved subject.
There are just as many ways to suspend diffusion in front of a light.
Here is a basic primer on setting C-stands.
 
In my opinion, booming is the best and most versatile way to arm out a fixture with standard gear, but the cantilever method is most often seen on big sets.  The problem with the cantilever method is that the strap or trucker's hitch has to be reset every time you want to move/adjust the height/angle/extension of the arm.  Since there is always downward stress on that arm, it is a hassle to reset a cantilever.
Again, there are plenty of specially made boom rigs that fit on combo stands or C-stands.  A popular such rig is the menace arm.  Relatively recently, versatile cantilevers rigs have appeared, such as the Matthews Max and Max Mini.
By the way, if you are not familiar with the set lighting hierarchy, you should know that there is usually only one gaffer on set.  The only exceptions to having more than one gaffer occurs when there is a B-unit or C-unit, or when there is a separate rigging crew.  Likewise, there is only one key grip if there is only a single unit and no rigging grip crew.
Here are the typical ranks regarding lighting personnel in most big, departmentalized shows with separate electric and grip rankings:
GAFFER (Electric Department);
       - BEST BOY ELECTRIC;
            -  THIRD ELECTRICIANS (usually 3 or more);
       - KEYGRIP  (Grip Department);
            - BEST BOY GRIP;
                   - GRIPS (usually 3 or more).
Essentially, the electricians do anything that directly involves lighting fixtures and power on set.
The grips are in charge of "outboard" light controls that do not touch the lights, such as flags, scrims, silks, frames, etc., and they also provide some set rigging for fixtures and set pieces.  Grips are also in charge of camera support when it involves a dolly (hence, the dolly grip).
Most grips nowadays will dispute that they take orders from the Gaffer in regards to lighting, but it certainly was that way for a long time.  Until a few decades ago, there was no such position as a "Best Boy Grip."  The "Best Boy" was only a management position in the electric department.  Grips eventually realized that they also could benefit from a middle manager.
 

Sorry to everyone for taking this off topic, but I have to ask something
@tupp : Can I interrupt and ask you a question about c-stands???
Since I know you have experience with such things, do gaffers actually hang lights from c stands on grip arms and gobos? 
I have to ask because so many people on youtube say that the "proper" way to boom lights is use a c-stand and a grip arm, but I have also seen a few people say that is completely wrong. since C-Stands have a narrower footprint than spreader stands are are more likely to tip over (even with sandbags). 
I thought that most gaffers would mount lights either on a spreader light stand, or if they were to use a C-stand, they would mount the light on on the baby pin of a c-stand, and then use a grip arm on a separate c-stand to hold diffusion in front.
I though booming lights was supposed to be done on a light stand with a (counter-weighted) boom arm.
Any insight would be greatly appreciated.

Nikolay Bauman is certainly a well done and engaging movie.
In the shot you mentioned at 28:49, it's a very nice, beautiful touch to have the light beams through haze/smoke/steam/fog to accentuate a large space.  However, it's not as if that lighting gag hadn't been done a zillion times before (nor since) 1967.
In regards to the off-shot/off-scene dialog pickups, they are certainly effective and add interest.   Of course, those audio editing techniques were in use well before 1967.
As for Soviet movies from 1967, there was a small project that year that had some interesting cinematography/editing.  Here is one scene from that film that I think does a decent job of utilizing "the language of the camera," although there is nothing particularly special about the lighting.
There is a nice little crane shot at the 03:23 mark.

Loved everything in that shot... Minute 28:49 -- take a look on that lighting!
By the way and here's another shot (the thesis or antithesis as you wish of the whole Soviet period's collective when individuals emerge from) and another scene where sound is used not from frame but into the frame (Lenin defended the allied Bauman when he got pregnant the woman of a fellow and she hanged herself) over the children's realm.
Calls to me more prone to be classified as masterpiece :- )
 

@tupp Merci!!!

Is this simply because the only (or the most convenient) lights they have are fresnels? Or is there some other reason.
  
Yes, as I said I do use panels as well. But this discussion is about getting equivalent output/quality as a COB keylight with a large softbox - this light can't compete in that respect. Doesn't mean it doesn't have it's purpose.
  
Yes, it's all relative. But the original question did quantify what soft light means in this particular discussion - the equivalent of a 4x4 silk or large softbox in very close proximity to a talking subject (so with the exception of some parrots, that would suggest a human-sized subject!).
  
Yes, as I mentioned you can do that, but not at equivalent prices to most COB lights that I am aware of (any decent 300W LED panels under $500?). If budget wasn't a consideration I'd just get an LS1200D rather that wondering what the most output I can get out of my current lights is!

Of course.  The larger the source, the larger the specular highlight.  That's why it is best to light flat art and walls with a smaller source -- there's less chance of glare problems because the highlight is smaller.
 
 
A big variable in regards to "harshness" and/or contrast of specular highlights is the distance of the light source from the subject.  The closer the source is to the subject, the greater the subject's diffuse value relative to the highlight value -- so as you move the source closer, the contrast ("harshness") decreases between the highligts and the subject's diffuse brightness.
 
 
Thank you for the kind word!

Some open-faced focusable sources can produce a double cast shadow in the outer parts of the beam, when focused to "spot."  So, cutting into the beam with barndoors or a flag can sometimes not give a clean edge as with a Fresnel.
I tend to use open faced fixtures, as that double cast shadow usually is not apparent, and because they are more compact and lightweight than Fresnels.
 
The Lowel Omni light.  A great, lightweight, compact, powerful and exceedingly versatile fixture.  It's focusing range is greater than many Fresnels.  Always use a protective screen on the front of the fixture.  Use FTK bulbs with a filament support, and avoid off-brand bulbs.  The focusing mechanism is very fast and can break the bulb's filament if one is not careful.

I am a little confused by this (Again, I come from a photography background, but I haven't seen anything to contradict this).
In terms of shadows, I understand that softness  "is a matter of degree between a point source and completely surrounding your subject with a smooth light source."
But wouldn't there still be a difference in specular highlights? I know that (in still photography) when a silver-lined umbrella is used, the specular highlights are stronger (more pronounced / more contrasty) than when a white-lined reflective umbrella is used. (And they are even more contrasty when using a non-bounced light.)
P.S. Wanted to say thank you again for your input in this conversation. 

You call a diffuser a "scrim" -- do you have a background in still photography?
 
Generally, a Fresnel will be significantly less efficient than an open-face fixture.  A lot of the light is lost when it strikes the inside of the housing of the Fresnel fixture/attachment.
 
An open-faced focusable source would be better and more efficient in this situation.
 
 

Not sure what is meant by "doesn't really do a good job in 'full flood,'"  A Fresnel attachment on an LED fixture might be disappointing to one having experience with tungsten and HMI Fresnels.
Regardless, the range of beam angles from a focusable fixture/attachment depends on a few variables.
With Fresnel fixtures, the source is always closest to the lens in the full flood setting.  So, if the Fresnel attachment doesn't allow the LED to get close to lens, then the beam angle will not reach its widest potential.  Of course, there are safety reasons why the light source should not get too close to the lens.
On the other hand, if one can just remove the lens/attachment, then it's best to just use the fixture without the lens, one wants to go really wide and use all of the output from the source.
By the way, it is dangerous to run a tungsten or HMI Fresnel without its lens.
 
I don't advocate using Fresnels to illuminate diffusion -- it doesn't make a lot of sense to do so.  However, I see it on set often.
Fresnels and other focusable fixtures are more than "fun to play around with."  If one knows how to use them, they are a valuable tool that "play" often on set.

Yes!
Thanks. Good to know. I certainly wasn't aware of that.
 
Again, good to know. Thanks.
That raises two questions though:
1) When would you choose the Fresnel over an open-faced focusable source?
2) Can you give us an example of a (more-or-less affordable) open-faced focusable light (or modifier)?

My fresnel attachment that I use on my Godox COB lights doesn't really do a good job in "full flood", though it works great when in spotlight (which is my primary use for it.) I imagine you'd get better results from a nicer one then? 
I'm not on major sets, just small commercial ones, and I've never seen a fresnel attachment being used with diffusion, so I find that interesting. I still feel like the op would be better off using more lights instead of a fresnel attachment. Not to say he shouldn't get one, as they're very fun to play around with and good to have in your kit, I'm just not sure that it's the solution he'd want to go with for diffusion?

He literally says in that video that the light is too harsh on its own. 

I own and use a couple of 1x1s and they are simply not large enough for a soft key. They're great for backlights, quick 'n' dirty portable/field/battery setups, or even as an eye light outdoors, but if you want soft light they come nowhere near competing with a COB light pushed through a softbox or scrim (at equivalent prices). Of course you can use a panel with a scrim or reflector too but most simply do not have the power. It's fine for his indoor setup, where he doesn't have to balance any ambient light and has a fairly tight frame so the light can be just a few feet from his face, but I doubt the setup he's demonstrating in that video would work in very many real scenarios (eg setting up an interview in front of a window in a cluttered office space).

I think that when shooting through a scrim, you are correct. Moving the light far back enough to get an even spread is going to make the lights more or less equal, regardless if it is a fresnel or a cob with a dish. 
On the other hand, if you are actually shooting in a softbox, you are actually bouncing the light around so that the light can be closer to the diffusion material and still cover the entire area of the front diffusion.
Plus if the COB light is in an enclosed softbox, you won't have the spill that you would have from bouncing it off of a scrim. All that spill is just wasted light. I don't know the exact mathematics but I am pretty certain that when inside a softbox, the light that is bounced off the front diffusion material (and bounced around the softbox), eventually makes its way out to the subject, but at some reduced amount.
In terms of bouncing light off the wall or a ceiling, I guess that yes, you would have to back the fresnel or COB with dish further from the wall. This could be good or bad. If bouncing off a wall, you would probably want to use a COB with dish to get the light further away from the talent (and further from the mic) as you could move it closer to the wall than a fresnel.
When bouncing off a HIGH ceiling, it might be easier to use a fresnel because you wouldn't have to raise the light as high to achieve the same light spread. This would be applicable in a place with high ceilings. But in a place with low ceilings, the fresnel might be at a disadvantage as you might not be able to get it low enough to get the amount of spread you want.
Ideally, I think the best solution would be to get a COB light with an optional fresnel attachment.
Also, a disclaimer: all of my practical experience with fresnel lenses / attachments is from shooting flash photography with strobes. The AD-200 and other strobes I use allow for either a bare bulb or fresnel head on the same light, so the only variable is the actual head. 

I don't think you'd get the spread you'd want / need since the light would be concentrated in one spot on the silk, though I've never tried it and never heard it being done. 

In my experience of trying to maximize efficiency of lights, the answer is no.
In your example, at the same distance if you used the fresnel vs softbox, the fresnel would produce a small hotspot which is totally useless for soft lighting.
If you then moved the light with the fresnel back to cover the same area, it would be farther away and the intensity would greatly decrease.
If I've learned anything about softlighting it's that nothing beats more power.  The most effective way to get more soft light is to literally get more lights.
 
 

Don´t forget that years ago most cinema lights were fresnel

I think a fresnel could come in handy when:
1) Bouncing light
2) Illuminating through a window or cookie for a hard light / hard shadows.
3) When you need to use more than one light for a diffused key, and you can shoot two (or more) fresnel lights through a scrim (since we can't really fit more than one light in to a softbox, can we???)
4) When you want a spotlight effect

I like fresnels, they are in my opinion the most flexible type of lighting. However, if you want soft light, an LED panel will usually be more quiet and softer. You can do some nice bounce lighting with fresnels which are impossible with LED panels. Pointing it at a white ceiling or white wall basically produces a light source anywhere, even if it's rather far away. Fresnels are also much better at making hard light. For learning how light properly and to be able to experiment with light, nothing really beats a fresnel light.
Conclusion: fresnels are a lot of fun

I have the same problem as well, the revert procedure didn't work, anybody has done it?

Normally my wife and I normally make documentary films as our creative outlet.  We just produced and shot a narrative short film.  Man, that shit is hard to do.  God bless the intrepid.  That is all.
https://www.facebook.com/AGiftForAllAgesFilm/

I'll be "that guy" and point out CD's DR comparison actually shows the 12k slightly ahead of the 4.6k. In Braw, they measured 12.1 stops on the 4.6k G2 scaled to UHD. Downscaling the 12k to 4k gave a SNR to 12.4 stops, with a note that there is more data under the noise floor than the 4.6k has. I'd argue that the 4k-normalized number is better for comparison, because if you're looking to maximize SNR in 12k than obviously the 4.6k won't even compare.
Worth noting though, they showed that the 12k only does that well shooting in 12k and downscaling in post. Shooting 4k in camera produced only 11.3 stops.