Arri Fresnel vs Open Face

[David G. Smith]

According to Arri themselves the new 2K open face is just redesigned in the reflector to give off more light than its predecessor. So you get slightly more bang for the same amount of wattage and if you are going to shoot it through a silk or similar anyways, sure, use the open face for more punch (if you need it…)

Maybe you should also for fun try to compare shooting par cans through a silk and compare them to arris open faces. Par cans are below cheap and pack quite a punch as well.

The thing is, when shooting through diffusion, the quality of the light you get is directionally proportional to the size of the bright spot shown on to (through) the diffusion. A bright open faced light of equivalent wattage would have more "Punch" than a Fresnel, in most instances. However, controlling the size of the the bright spot shown on to (through) the diffusion would mean that you would have to physically move an open faced fixture closer or farther away from the diffusion. The zoom from spot to wide control on a Fresnel fixture means that you can control the bright spot by adjusting the light in place; within reason of course. This might make a big difference in tight spaces. I always seem to be in tight spaces.

I am a big fan of PAR 64s also; best pure output for the money in my book.

 

[eiker_ir]

which models or PAR fixtures would you guys recommend? The more power and the more compact the fixture the better

 

[CharlesPapert]

I haven't used the new Arrilites but have shot plenty with the Arrimax HMI's which use the same reflector design.

Yes, if pushed through diffusion the differences between these and a fresnel are greatly reduced. And it is reasonably fair to say that the reflector shapes the beam in a way that sits between a fresnel and classic open face. Where you will see the difference is when working direct with no diffusion. And while it is less typical to use raw light on actors, it's not at all unusual to do so on backgrounds, as say a sunsplash. Or, if you are looking to throw a hard pattern through a gobo, like venetian blinds. A fresnel will allow for a much cleaner cut via barn doors than an open face, with the Arrimax reflector again somewhere in the middle.

What I have seen with those reflectors is that you will get a primary shadow that is reasonably pronounced, with multiple light shadows around it which are coming off the reflector vs the bulb. In most instances you wouldn't register that but it's something to be aware of in case you end up doing a tight piece of coverage where the shadows may reveal themselves.

I would in pretty much all instances take the modern reflector over the classic open face, because of the increased output. As noted by others, most of the time you are using an open face for spread and punch, and the Arrimax reflector delivers in both instances, as well as having a really fantastic spot to flood ratio. However I still consider it an open face light and if I'm looking for the control and clean edges of a fresnel, I'll use that or a Leko.

One last note: when bouncing a light, there is an interesting voodoo about maximizing the output of the output of the bounce. Spotting the light in will appear to increase the output of the bounce when you look at it, because the hot spot becomes hotter, but you are also reducing the size of the reflected bounce in the process and that can actually drop the level (as well as make a less soft source). Generally there is something of a curve involved, where once you start to spot in a little you are still filling the bounce but have increased the level, and as you continue to spot in the level may start to go down. With the Max reflectors, there is a huge upswing in output as you start to spot in from full flood, and though it will level off as always as you get towards spot, that 1/4 of the way towards spot setting tends to deliver a significantly greater output than one sees from any other kind of unit. I had an M18 (1800W) actually match the output of a standard 12K (12,000W) in one instance when both were pushing through diffusion. Quite impressive.

 

[Moseph]

But this is still NOT the new reflector.
Im asking how will the NEW reflector make a difference? It says its much better and almost just like a fresnel.

Who says that? It's certainly not the truth. You still have a double source going on, light from the reflector will find its way around the barn doors unlike light coming directly from the filament. Like what's been said - you get a better flood to spot ratio and a bit more output, not much more control though.

Which Source 4 are we talking about? The new Fresnel or the PARnel? I've not tried the new Fresnels yet.

The standard source 4 ERS.

which models or PAR fixtures would you guys recommend? The more power and the more compact the fixture the better

They're all the same, there's really nothing to the actual fixture. It's a sealed beam lamp. You could get those $300 mole richardson PARs that are a little more compact and much more durable than the $20 chinese PAR cans, but for what we do they're practically disposable. Don't think that having barn doors is an advantage of the Mole ones either, they don't do anything.

There's also source 4 PARs, they're apparently a bit more efficient than a standard PAR64 lamp, they're more compact, and they use interchangeable lenses so you don't have to carry around 3 or 4 different types of (large) lamps to go with the fixture. Changing out the lenses can be exceedingly frustrating though.

One last note: when bouncing a light, there is an interesting voodoo about maximizing the output of the output of the bounce. Spotting the light in will appear to increase the output of the bounce when you look at it, because the hot spot becomes hotter, but you are also reducing the size of the reflected bounce in the process and that can actually drop the level (as well as make a less soft source).

Agreed, and this voodoo can have disastrous results with something like a 4k PAR. I don't think many people would be crazy enough to bounce anything larger than a 6k with no lens, but I've seen a 4k with no lens burn right through an ultra bounce from a good 6 feet away within 30 seconds of the lens being removed.

Another note on the new MAX reflectors - watch out when you're renting these lights (HMI's) for the position of the globe. On half the ones I come across around here, the lamp is no longer in the "sweet spot" in the center of the reflector, but begins to sag down from getting banged around too much. When this happens, the beam has a doughnut shape rather than an evenly filled circle from full flood to about halfway spotted in.

 

[CharlesPapert]

When this happens, the beam has a doughnut shape rather than an evenly filled circle

Mmm doughnuts. Especially evenly-filled ones.

 

[theuniverseinanutshell]

First of all, my apologies for reviving an old thread, but it seemed like this was the most appropriate place to post it as my question concerns the fixtures discussed here. I was after sourcing a light fixture whose main job would be to punch through or bounce against diffusion (and possibly, periodically in a chimera), and so naturally, I had my eyes set on open-faced units. Upon closer look however, I see that the fresnel equivalents output a higher lumens than its open-face counterparts, judging from their photometric data (Arrilite 2000 plus v. Arri T2 v. Ianiro blondes). How is this so: I thought the sense in preferring open-face units on diffusion is their luminance advantage? Have I misunderstood the rationale and/or misread the charts? I'd very much appreciate some clarification.