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reducing light from lamp


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#1 MattGrover

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Posted 12 December 2005 - 04:29 AM

Well, that's an iffy title!

Basically I would like to know, what the best way is to reduce the light coming from a plamp without using a dimmer.

E.G.

If I'm working with a kit consiting of 4 x 800w redheads and I want to get different levels of light from them, is it best that I use ND gels or scrims?

I understand how ND's work, haven't come into contact with scrims yet, although I've read a bit about them.

Cheers :)

Matt
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#2 Brian Drysdale

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Posted 12 December 2005 - 06:08 AM

Well, that's an iffy title!

Basically I would like to know, what the best way is to reduce the light coming from a plamp without using a dimmer.

E.G.

If I'm working with a kit consiting of 4 x 800w redheads and I want to get different levels of light from them, is it best that I use ND gels or scrims?

I understand how ND's work, haven't come into contact with scrims yet, although I've read a bit about them.

Cheers :)

Matt


Usually I just use the ND gels. You can change them much quicker than the scrims, which I'd use as a first base then add the NDs. The problem with the ND is that they tend to fade and discolour. The Redhead kits usually has scrims, so best way is to have a play.
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#3 Chris Keth

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Posted 12 December 2005 - 07:03 AM

Usually I just use the ND gels. You can change them much quicker than the scrims, which I'd use as a first base then add the NDs. The problem with the ND is that they tend to fade and discolour. The Redhead kits usually has scrims, so best way is to have a play.



I generally just use scrims. I'd make sure you have a good ample scrim pack with each head.
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#4 Brian Drysdale

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Posted 12 December 2005 - 08:56 AM

I generally just use scrims. I'd make sure you have a good ample scrim pack with each head.


Both methods work, although not too many lighting kits here have scrims, you'd have to ask for them. Interesting to know if they're used more in the USA than in Europe.

Gels have the advantage that they can be used on any light, although once you start getting a filter pack of diffusion and various gels they tend to overheat.
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#5 Don Bachmeier

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Posted 12 December 2005 - 09:13 AM

Are there not smaller wattage bulbs for Redheads? That in combination with a couple full sets of wires (scrims) will get you from full power to next to nothing output. Don't be surprised if your bulb life goes down a bit if you regularly stack scrims. Sometimes contains the heat; though I don't have much experience with Redheads.
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#6 Michael Collier

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Posted 12 December 2005 - 02:58 PM

If you dont have a Genny or access to more than one circut I would recomend getting an assortment of bulb wattages. 2000w is basicly your max so you cant have every light on one circut. If you put a 200w bulb in the redheads, you save power, so all lights can go at the same time, you cut light without using either ND or scrim and you reduce heat in the working environment (something everyone will thank you for) I hate using ND or scrims unless nessicary. I can look at a light and tell what bulb needs to go in it to bring it into value. then I use a half scrim or move the light back to fine tune it.
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#7 J. Lamar King

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Posted 12 December 2005 - 03:09 PM

Personally I'm not sure how I could work without scrims. Especially on location. Sometimes you can't move a light back or you don't have a smaller unit or that unit won't cover etc. It's so easy to take a reading and just drop the scrims you need to fine tune the light. That's what they're for after all. I've stacked them deep at times too. That would usually be on a backlight where I just keep shouting "Less! Less!" until it looks right.

Edited by J. Lamar King, 12 December 2005 - 03:12 PM.

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#8 Brian Drysdale

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Posted 12 December 2005 - 03:51 PM

If you dont have a Genny or access to more than one circut I would recomend getting an assortment of bulb wattages. 2000w is basicly your max so you cant have every light on one circut. If you put a 200w bulb in the redheads, you save power, so all lights can go at the same time, you cut light without using either ND or scrim and you reduce heat in the working environment (something everyone will thank you for) I hate using ND or scrims unless nessicary. I can look at a light and tell what bulb needs to go in it to bring it into value. then I use a half scrim or move the light back to fine tune it.


The Redhead is designed to run 800 watt 240V and if I recall 1000w 120v lamps (I believe there used to be a 30V bulb). If you want to change wattages get a range of different wattage lights, not bulbs. A good lighting kit will have a range of different wattage and types of lighting units. I suspect you'll run into difficulty sourcing smaller wattage bulbs that'll fit the Redheads and changing hot bulbs as you want to set your lighting levels doesn't bear thinking about. Changing bulbs when they blow is bad enough, it always slows things down.

The power is more of an issue in the US, in the UK you can run 3 Redheads of a standard 13 Amp mains socket no bother, I've had 4 on occasions.

You can move your lights back, but it's not always possible and moving the light out of a closer position will change your lighting effect.

A common method is to put a larger light than you need then scrim or ND it down, then you won't need to change lights if it's not powerful enough. That's the American method. In Europe we just put the right lamp up in the first place (of course). ;-)
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#9 MattGrover

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Posted 13 December 2005 - 04:42 AM

Hi all,

Thanks for all your replies!!

It seems that there's a multitude of people's preferences (as usual!! ;) ), I'm going to be doing some tests in the new year, having briefly looked at scrims, just to add further confusion for me ;) there seems to be loads of different types.

Is there a bog standard type of scrim that I can pick up when I get the lights, that will enable me to try out various ideas and suggestions, or will I need a selection of different types.

Thanks again everyone!!

Matt
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#10 Brian Drysdale

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Posted 13 December 2005 - 05:40 AM

Hi all,

Thanks for all your replies!!

It seems that there's a multitude of people's preferences (as usual!! ;) ), I'm going to be doing some tests in the new year, having briefly looked at scrims, just to add further confusion for me ;) there seems to be loads of different types.

Is there a bog standard type of scrim that I can pick up when I get the lights, that will enable me to try out various ideas and suggestions, or will I need a selection of different types.

Thanks again everyone!!

Matt


A new Redhead kit usually comes with two densities of full scrims, plus the same in half scrims (covers half the lamp face). This is really only a set of scrims for one light head, check with the people who are supplying the lights what they have available and take all the different types and test them.

Look at the online Matthews catalogue, they have a full range of scrims (lots of other stuff as well) and you can see the different types. Interesting how terms vary, because what is described by most people as scrims (and the people here) is described as wire diffusion by Matthews. They call nets scrims.
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#11 MattGrover

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Posted 16 December 2005 - 09:03 AM

A new Redhead kit usually comes with two densities of full scrims, plus the same in half scrims (covers half the lamp face). This is really only a set of scrims for one light head, check with the people who are supplying the lights what they have available and take all the different types and test them.

Look at the online Matthews catalogue, they have a full range of scrims (lots of other stuff as well) and you can see the different types. Interesting how terms vary, because what is described by most people as scrims (and the people here) is described as wire diffusion by Matthews. They call nets scrims.


Ok, this may be where I'm getting a little confused..when I've been talking about scrims, I've been thinking (from what I've handled before), white fabric stuff rather than metal mesh plates, presumably the two methods offer different styles (?) of light reduction??

Thanks for all the replies on this by the way :)
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#12 Ron_mc_Don

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Posted 18 December 2005 - 01:54 PM

Scrims are just like expensive baking paper. They soften and diffuse the light.

Can someone please explain to me what ND gels are.

Thanks,
Tony.
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#13 Brian Drysdale

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Posted 18 December 2005 - 02:55 PM

Scrims are just like expensive baking paper. They soften and diffuse the light.

Can someone please explain to me what ND gels are.

Thanks,
Tony.


Using the "Set Lighting Technician's Handbook" the definitions are:

SCRIM: A circle of wire mesh, which slides into the ears on the front of a fixture and reduces the intensity of the light. A single dims the light by about half a stop. a double is about one stop. A half-single or double affects only half the beam

ND (neutral-density): A gel or filter that reduces light transmission without altering the colour of the light

NET: A black honeycomb netting material sewn onto a rod frame that is used to reduce the intensity of part or all of a light's beam

DIFFUSION: Material used in front of lighting fixtures to reduce the light they produce.


The "expensive baking paper" is diffusion.

The ND gels are lighting gels that come in various grades 1 stop apart like camera filters. ND 0.3 is 1 stop (often described as ND3) ND 0.6 is 2 stops (ND6) and ND 0.9 is 3 stops (ND9)

The nets often mounted on C stands like flags are, their frame is similar those found in flags. Although some net frames are left open across one edge, so that the frame doesn't cast a shadow across the subject.
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#14 Ron_mc_Don

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Posted 19 December 2005 - 09:55 AM

Using the "Set Lighting Technician's Handbook" the definitions are:

SCRIM: A circle of wire mesh, which slides into the ears on the front of a fixture and reduces the intensity of the light. A single dims the light by about half a stop. a double is about one stop. A half-single or double affects only half the beam

ND (neutral-density): A gel or filter that reduces light transmission without altering the colour of the light

NET: A black honeycomb netting material sewn onto a rod frame that is used to reduce the intensity of part or all of a light's beam

DIFFUSION: Material used in front of lighting fixtures to reduce the light they produce.
The "expensive baking paper" is diffusion.

The ND gels are lighting gels that come in various grades 1 stop apart like camera filters. ND 0.3 is 1 stop (often described as ND3) ND 0.6 is 2 stops (ND6) and ND 0.9 is 3 stops (ND9)

The nets often mounted on C stands like flags are, their frame is similar those found in flags. Although some net frames are left open across one edge, so that the frame doesn't cast a shadow across the subject.


Thanks heaps! Wow, my year TAFE was money well spent then (note the sarcasm). I should've just payed this forum the money. LOL
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