AIEL Shop Tips

Even with today's dichroic colour changer and LED
systems, plastic colour media is still the most
popular method of providing stage lighting tint.
From basic weekend musical group lighting and disc
jockeys, through professional theatre, to the largest
touring rig, the ubiquitous "gel" still finds its place.

Here are some tips to assist the lighting maintenance
crew in getting the most life and greatest usage out
of these simple, inexpensive, coloured sheets.

  Topics

Preliminary

CUTTING

  Table Method

    In order to cut gel, it is best to have a flat table large enough to handle the sheet or roll. Screw masonite or wood to the top of it to handle the knife marks. If you cut rolls often, build a jig to hold the roll on a dispenser. Attach a metre stick on the edge of the table and designate a `zero' mark from which to measure. Have another metre stick made of metal to use as a straight edge and to measure in the other direction. Metal is preferred because the razor knife would eventually whittle down a wooden one.

    Always cut slightly smaller than the frame size so as to ensure a proper fit without gel sticking out. This is especially important if you tape the sides of the gel frames shut. It is far easier to insert a cut gel piece into a frame when it is not rubbing the taped sides.

    An exception to the "cut smaller" suggestion is regarding acetate and polyester gel. They tend to contract over time after exposure to high heat. Eventually they may shrink enough to allow a sliver of white light out. So to prevent that, cut these gels the same dimensions as the frame size and try to bind each tightly within a metal frame. Bound metal frames will help keep these gel types from buckling and contracting so easily.

  Frame Method

    A procedure that works well for sheet sizes of gel is to place a corner of the gel sheet into the frame and to cut around the frame with a razor knife or a gel cutter. The latter consists of a small, flat holder with a razor blade inside. One edge has an opening to expose the blade. One slides the cutter along the outside of the frame in the manner of a letter opener, cutting the gel to the correct size. To do this well, allow the frame side to extend over the edge of the table slightly. With one hand firmly holding the frame and positioned gel sheet flat, use one quick motion with the cutter angled up to skim along the edge and cut the gel in a single motion per side.

    Once again, before cutting, place the gel slightly inside the frame so as to end up with a smaller gel cutout than the outside dimensions of the frame -- acetate and polyester gel types excepted. This will take practice to get the right technique. While learning, expect to bind the blade and to crinkle a few sheets.

  Gel Marking

    Once gel has been cut, label it. This will help you to discern like colours. It is also a plus to a pickup crew that is unfamiliar with manufacturers' number designations, and is thus unable to associate a colour with a number. Even for the experienced, like colours can be hard to differentiate when un-numbered.

    Use a gel pencil or china marker to put the number in the upper right corner outside of the frame's projection opening. Make it large so as to be readable in dim light. If you use more than one manufacturer's gel, place a letter in front of the number so as to distinguish one from another. Light colours can be labelled with a black felt-tip marker or black gel pencil.

GEL SCRAPS

    Cut each gel in a manner that will make most out of a sheet. That is, don't cut four squares, one out of each corner of a sheet, leaving a cross in the middle. Cut each frame, one next to another. The left-over piece may not cover the frame size you just cut, but it could fit a pinspot or followspot colour pack, or be used in an internal colour wheel in a moving light or special effect. Even the little scraps can be used to colour flashlights, dashboard lights in automobiles, LED lights, and so on.

    Photographers may want small scraps for photo flashes; artists may want them to produce other effects. The act of giving out gel scraps is always gotten back in good will, and when you or someone else uses them, it keeps yet more things out of the land fill.

If you must throw it out, please place it in a
plastic retail bag and send it to the recyclers.

HEAT CONCERNS

• Choose fixtures that use heat-reducing lens coatings.
• Choose fixtures that use heat-reducing reflectors (cold mirrors).
• Choose fixtures that have long snouts.
• Choose fixtures employing open-edged gel frame holders.
• Use the farthest frame holder position from the light source.
• Clip gel to a snoot or barndoor to increase the source/gel distance.
• Punch pinholes into the gel.
• Place a heat filter between the gel and light source.
• Lower the lamp wattage.
• Use long-life lamps of the same wattage. They put out less heat.
• Reduce the dimmer setting.

OLD GEL

• Clean dirty gel with soap and water. After drying, use a soft cloth and furniture polish to buff it back to life. Be sparing with the polish. It leaves a residue. (See "Rejuvenation", farther on.)
  
  
• Scratched gel might be used for times when a bit of diffusion is required, or used when the spill or light loss is not objectionable. Some light scratches might be able to be buffed out or reduced. (See "Rejuvenation", farther on.)
  
  
• Faded gel that is not physically damaged or brittle can be re-catalogued according to colour. That is, look at the gel; gather like colours and fade amounts together. Mark them accordingly and then clip them together or put them into a separate envelope. Now simply use these where a pastel shade of that colour is required.
  
      You can also combine faded gel to get darker colours. Sort so that combined shades are consistent and then staple each group of two or three sheets together. Mark them and store the groups in a separate envelope.
  
     Gel Inspection Methods to Consider:
  
  • Place the gel sheets to be compared next to one another
    on a white sheet of paper or cardstock illuminated by a
    bright, white light. Differences will quickly become apparent.
    
    OR...
    
    
  • Stand in front of a white light. Hold two gel sheets
    up side by side close to your eyes and look through
    them at the source. While retaining focus strictly on
    that light source, move the gels back and forth as a
    unit. Do not refocus your gaze to the gel while doing
    the comparison. If there are any differences, you will
    see the source dim and brighten and/or change colour
    as the sheets are moved across your field of vision.
    Determine from this which sheets belong together.
  
  
  
• For gel you no longer want that might have some life left, give them to a needy lighting student, theatre group or school. Explain what has happened and how those sheets might still be used for some purpose. As long as there is some colour left, faded gel does not necessarily mean the end of its useful life.

Again, if you must throw it out, please place it in
a plastic retail bag and send it to the recyclers.

REJUVENATION

    It is possible to bring some gel back from the dead. As was discussed in "Old Gel", one can wash dirty colour media, but it is also sometimes possible to bring back hazy, scratched gel to a usable level. Those that have big budgets won't bother, but those without that luxury, persons that wish to be frugal, and those that want to keep as much out of land fills as possible, will strive to get the most life from their gel.

    A good product that can rejuvenate dirty, scratched colour media is ARMORALL. After cleaning and drying the gel, put a small amount on and rub it in with a soft cloth. It actually reduces the diffusing effects of small scratches, and can often buff the gel back to usable life.

    For really bad gel, evenly smear the ARMORALL on and leave it over night. The next day, wipe off the excess and polish to a lustre. Repeat for the other side.

STORAGE

  Flat Storage

    It is suggested that uncut sheets be kept unrolled in an archetect's portfolio style of a large chest of drawers, preferably one drawer for each general gel colour, if one can afford the drawers and has the space. Within each drawer, the gel can be further divided by colour number. Separators can be made from bristol board or heavy card stock, for say every ten numbers. This will make for easy selection of a particular number.

    Outside of a cabinet, find a large shelf or table top where the gel can be stacked and where nothing is likely to be placed on top of it. The drawer, shelf or table should be at a height that allows one to easily view the corner labels that identify the colour name and number.

    It is recommended that you stay away from cardboard drawer "cabinets". They don't operate well and they bind too easily after a large number of sheets are inside. Whatever method of flat storage, be sure to employ paper separators between sheets to prevent them from sticking together.

  Hanging Storage

    Some people will make up a gel closet where sheets are hung on hangers by clothepins, or they use retail clothing hangers that have built-in clips. Don't drape the sheets as they will get a crease and are more likely to fall off during colour-number hunting. Even with the clips, marks will be left on the sheets. Fortunately, they will be on the edges where they will not cause deformation of the part that falls within the beam of the light. Cloudy or crinkled gel within a light beam can cause unwanted spill. It is also more likely to trap heat and thus shorten its life.

    Be aware that the problem with the hanging method is that not too many sheets can be hung on clips before their weight will allow one or more to slip out and end up on the floor. So either use a lot of hangers or select a flat storage method. Lay the gel flat on a counter or table top when removing or adding sheets to the clips, and then hang it up immediately afterward.

  Rolls

    Gel that comes in rolls is best stored rolled up. Typical lengths of seven metres generally precludes storing it flat. Even if one had the space, new rolls would have too much material to easily handle. Storing rolls horizontally means a shelf with sides to prevent them from rolling off and a depth of typically one and a quarter metres. Most lighting people simply store them vertically. Always leave rolls in their protective plastic coverings in which they are usually shipped.

  Cut Sheets

    If you have the space, cut sheets are best stored in a literature rack. These have multiple compartments that easily fit cut sheets up to a PAR 64 gel frame and larger. Use replaceable labels to sort gel by manufacturer and stock number.

    Cut gel may be also stored in an accordion file folder or in a standard file cabinet. In the latter, use file folders or envelopes to separate by colour or number, and catergorise by manufacturer and size.

  Travel Storage

    When you are working shows, it is good to carry a Colour Kit with you. Even if the show is already gelled, you'll need spares for burnouts and damages that will happen on the road, and also to be able to handle requests for colour changes. Get a sturdy suitcase, or actual road case, if you can afford it. Inside, place cut sheets into one or two portable accordian files. One might be for colour sheets; the other could hold diffusion, neutral density, or other specialty filters, along with a swatch book. Some or all of the other items listed in the above link will round out your travel kit.

Caring for colour media will ensure that one does not
have to order replacements sooner than necessary.
This permits money to be put into new stock, thus having
a greater variety for those times that call for that one odd
colour to complete a desired look for a particular show.

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