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Old July 3rd, 2003, 07:20 AM   #1
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Enlighten a fool on scrims please.

Anyone care to explain scrims to me? I'm in the middle of aquiring my light kit (finally!) and I pretty well understand what full and double full scrims do... a single full reduces output by 1/2 stop and double full by 1 full stop.

I ALSO understand what a half scrim does, but my inquiry is more along the lines of practical use. I'm wondering if you can give me an example of the type of shot where I'll want to lower the output of just half of a light beam...

I could probably make up an imaginary scenario but I'd like to read some input from those of you who have made practical use of a half scrim... and why/how you did it.
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Old July 3rd, 2003, 01:02 PM   #2
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Hi Matt,
A scrim looks like a metal screen and acts like a neutral density filter. The density of the screen determines the amount of light it blocks-off. Basically, you would use it as you would a ND gel on a light that just needs to get cut back a bit for a shot. Nothing exotic.
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Old July 3rd, 2003, 08:21 PM   #3
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If you ever have to light a caucasian and a deeply dark skinned person at the same time, you will come to love the 1/2 scrim.
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Old July 3rd, 2003, 09:48 PM   #4
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Matt,

There's a thread here somewhere in which Charles Papert gives all the low down on lighting control. It's a great thread. I did a quick search but didn't come up with it. Search a bit yourself...maybe someone else will remember how to find it.
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Old July 4th, 2003, 06:50 AM   #5
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There was a guy who spent time on and off this board and it seemed like controversy often surrounded him... I had a bit of banter with him myself... but this guy does seem knowledgeable on a lot of these issues, even if there are personality conflicts.

This was emailed to me by Wayne O.

>
To answer your question: a half single or double scrim is used to cut the
light intensity of approximately half of the source, as you correctly
mentioned. A couple uses for this are; when you are lighting a med shot of
an actor, and you want his face in the light, but would like the light to
drop off on his torso. Top half of the light open, bottom half covered by
the half double.

Another example; a actor walks into a close up from ten feet away. If there
were no scrim on the light, he would either be underexposed at ten feet, or
over overexposed in his close up. Solution, drop in the half double with the
scrim on the bottom half. Adjust the light so at ten feet away he is in the
open, and when he gets to the close up position the scrim is taking effect.

Flags and nets do much the same work as scrims, but they are more selective
in the way they work. You can "feather" a net, but a scrim is where it is.
Of course, nets and flags require more work and gear.

Remember, you can stack scrims, so you can have a "double overall with a
half double on the bottom," for instance.
>

I just wanted to post this since it's exactly the answer I was looking for... after popping $350 per fresnel I wanted a good reason to follow that up with another $150 per light (in accessories)...

It's easy to get caught up in the tools and toys of this hobby and I try my best to differentiate between the two so I don't waste my money on toys when I want tools.
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Old July 4th, 2003, 09:56 PM   #6
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Matt

<< this guy does seem knowledgeable on a lot of these issues, even if there are personality conflicts >>

Knowledgeable people are not all that difficult to find, and I'm working on locating an expert or two to assist us with this particular form. One thing we can always do without, however, are personality conflicts, as they serve no constructive purpose here. When I started this board, I dedicated myself to eliminating personality conflicts so that we can concentrate instead on discussing useful information. These topics aren't rocket science, nor are they closely guarded secrets of arcane lore. Pretty soon I'll have some enlightened, professional, *personable* folks to help us out here... so please bear with me. Hope this helps,
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Old July 5th, 2003, 04:04 AM   #7
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Matt, singles and doubles are unquestionably useful with fresnels. Half-scrims are, in my opinion, somewhat less so. It depends how you use the lights, and Wayne's thoughts are 100% valid, but very often for video one tends to use diffusion on the lights, which renders half scrims close to useless. Again, as Wayne describes, flags and nets are the way to go as far as serious light control but they involve a great deal more hardware.

If you are on a serious budget, I would go with at least one single and double for each of your lights, and hold off on the halfs. If you can afford one more scrim, get another double. This gives you five half-stop increments of cutting power:

.5 stop: single
1 stop: double
1.5 stop: single plus double
2 stops: double plus double
2.5 stops: double plus double plus single

Another useful method of lighting control is a dimmer or rheostat. Depending on the wattage of the instrument, you may be able to use a standard household dimmer such as used on a table lamp, for instance. This offers quick and easy adjustment of the intensity (great for backlights that aren't easy to get to to drop in scrims). Be aware however that a dimmed down incandescent unit will become warmer in color as you dim it, and make sure the dimmer is rated higher than the wattage of the unit.
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Old July 5th, 2003, 11:16 AM   #8
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NRG Research offers light control modules that are very nice. Their product offers wireless remote control of light intensity with a system that reminds one of the X10 light control systems.

If, and it's a big if, they control the intensity in the same manner as their Varilight Pro, they pulse the lamp at high frequency which tends to reduce color temperature change as the output is adjusted.

Noticed that they also now offer L-brackets and reasonable-looking light mounts for cameras.
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Old July 5th, 2003, 08:58 PM   #9
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Open letter to Chris and group

"These topics aren't rocket science, nor are they closely guarded secrets of arcane lore."

But that does not entitle anyone to play fast and lose with the facts. Since you are on a search for "some enlightened, professional" persons, I would guess that you are acknowledging a certain lack of solid information in some areas by your present moderator force. This is certainly not a bad thing; there are very few individuals that know everything about everything, and very often those individuals are not so good with the "real world" experience. And it is refreshing when a moderator says, "I don't know, but I think I can point you to the person who does," rather than trying to fake it.

I have some issues with the way Chris runs this site, but hey, its his ballpark and he is entitled to make the rules, and choose who he wants on his team. It's up to those of you who come here looking for advice, and possible purchasing suggestions, to inquire as to the credentials of those giving the advice. Just because someone has a good line of patter, does not mean you should be dropping your hard earned dough based on their recommendations. They may only be a couple of steps ahead of you on the learning curve.

If Chris is engaging in a search to bring in additional competent people, based in part on the disruptions that I caused to the group karma here (quite unintentionally, btw), then I think it was time well spent. This is a good site with great potential to help a lot of people. And I wish you all well.

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Old July 5th, 2003, 09:21 PM   #10
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Howdy from Texas,

<< If Chris is engaging in a search to bring in additional competent people, based in part on the disruptions that I caused... >>

Sorry, but you can't have credit for this, as that search has been underway in full force since the very first day I started this board.

When it comes to finding moderators, if I have to make a choice between someone who knows everything about the craft or someone who has a friendly, easygoing nature, then the nice guy will win out over the expert everytime. Because the knowledge can always be found... we'll always cheerfully point someone in the right direction. Personality conflicts, however, can kill a community. I'd rather remove the problem. That's why personal grudges don't last around here.

With regard to the way this site is run, I challenge anyone to point out to me exactly how we're doing things worse than our competitors. The business model is nearly the same; except here you don't have banner ads cluttering the boards, and there's no anonymity, either. Along with the principle individuals behind DV Info Net, I stand firmly behind our method of operation, and although we're constantly looking for ways to improve it, the fact is there's nothing going on here that I'm not proud of. As I've said constantly from the beginning, purchase questions are the most serious ones we get here, and we're all dedicated to offering responses that have the best interest of the potential buyer at heart. It's that simple. Hope this helps,
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