3543 Views |  Like

Using Theatrical Lighting Gels to Filter and Color Correct Polaroid Films

In my quest to create interesting and evocative pinhole imagery, I have taken to experimenting with various types of polaroid film—both black and white as well as color. I like the immediacy of it and how the unexpected idiosyncrasies of the Polaroid, couples with the character of shooting pinhole. Recently, I have begun shooting with Polaroid’s color films—type 79 and type 59. Type 79, according to Polaroid, “features accurate colors and bright whites; sharp, vibrant,saturated proofs and final art; lower contrast for greater detail; improved reciprocity characteristics.” Type 59, according to the data sheet, is a “color print film balanced for daylight and electronic flash, (with an) extended dynamic range.”

Polaroid color film and the problem shooting pinhole

One of the beauties of shooting pinhole, is the extended exposure times. The increased time captures wind, motion and a lot of other interesting things that traditional lens photography misses. Unfortunately, with the Polaroid film, this extended exposure time can cause severe color shifts with the reciprocity failure.

In my experience, the Type 79 film shifts to the green with longer exposures, although occasionally I have been able to accurately capture the color of a scene. The Type 59 shifts to the blue-cyan. This shift, with the right image, can be quite interesting as it almost looks like a cyanotype, but if that is not the intent, then the results are generally quite disappointing.

In effort to compensate for this, I have had to resort to doing a lot of color correction after the fact by scanning in my images and post-processing in photoshop.

Cost of traditional filters

To counter the time spent behind a computer, I have been looking for an in-camera solution that I could use to compensate for the reciprocity color shifts with each of these film types. To date, though the costs for traditional photographic filters make it nearly impossible to build up a library of filters. Additionally, most of these filters are very small, I shoot with a 4×5 camera, and have yet to figure out how to rig these up to the camera in front of the pinhole lens. Since I also shoot 35mm, I need to have a solution that will work for all my cameras, regardless of lens type or configuration. Another factor to consider is that some color compensation may need to be done with multiple, layered filters.

Out of curiosity, I asked my sister about the lighting gels she used in the theater—she is a professional lighting designer—and whether or not these could be used in front of a camera. The answer was yes, so the quest began.

The idea: Use theatrical lighting gels to color correct

I researched the costs on the web, and generally a 20”x24” sheet of color gel material costs about $6 (give or take brand and shipping costs). Much cheaper than traditional photographic filters. Rosco, one of the more common and best known brands, even offers a suite of gels for photography which includes neutral density filters for 4 different stops.

The Rosco – Filter Facts website

With this new information in hand, I ordered a cross selection of gels: 2 ambers (light #RO16 and medium #RO310), two reds (light #RO26 and medium #RO27), two blues (pale #RO63 and daylight #RO65), yellow (daffodil #RO310), neutral densities (N.3 #RO3402, N.6 #RO3403, N.9 #RO3404), and a couple of magenta filters that reduce green (Tough 1/2 minus green #RO3313 and Tough MinusGreen #RO3308 (these filters look lavendar). I also bought the pre-packaged set for color correction which includes 16 10×12 sheets that correct for various light conditions including tungsten, fluorescent, blue shift, green shift and neutral densities.

There are others I want to try, but that’s for later.

I then took the sheets and made holding frames for them. I set up a still life to make sample images and took them out into the field. What follows is the step by step process for making the filter and frames and sample images using one or more gels at a time. The examples show both color correction and some interesting and fun effects.

No Filter Filter 3407

Still Life – with Oranges
Type 59
No filter
Overly blue cast due to the reciprocity failure color shift. The oranges look like lemons.

Still Life – with Oranges
Type 59
Using 1x 3407
This filter reduces the blue cast somewhat and actually makes the oranges look orange.
Filter 3408 Filter 3409
Still Life – with Oranges
Type 59
Using 1x 3408
Effect of this filter is very similar to the 3407.
Still Life – with Oranges
Type 59
Using 1x 3409
The shift in this is very subtle. The oranges are a little less yellow but the bougainvilla is not very pink.
Filter 3407 and 3401 Filter 3401
Still Life – with Oranges
Type 59
Using 1x 3407 and 1x 3401
Doubling the filters produces a muddy effect.
Still Life – with Oranges
Type 59
Using 1x 3401
Fairly similar effect to the 3408 filter.

 

79 No filter Filter 3411
Still Life – with Oranges
Type 79
No Filter
Still Life – with Oranges
Type 79
Using 1x 3411
Filter 3308  
Still Life – with Oranges
Type 79
Using 1x 3308
Filter 3411 twice Filter 3308 twice
Still Life – with Oranges
Type 79
Using 2x 3411
Still Life – with Oranges
Type 79
Using 2x 3308
All the images in this set have a green cast to them. Doubling the filters brings the color back to the oranges, but the blue vase color is lost. The bright pink bougainvilla color is retained better with the type 79. Overall doubling the Filter #3308 comes closest to a “true” color representation.

The Process

Framing the Gels for use

gels
materials
cut frames
taped frame

Images from Top:
– Gels before cutting, with backing paper.
– Simple materials used for this project   include x-acto knife and double stick tape.
– Cut frames from black plastic material.
– Closeup of gel attached to frame with   double stick tape.

  1. Buy the Gel sheets from your vendor of choice. (Adorama sells these as do any theatrical lighting supply house).
  2. When they arrive, roll out the 20×24” sheets onto a flat surface and set aside.
  3. To create the holders:
    • I bought a sheet of 1/16” black plastic at TAP plastics, but you could used poster board or thin matte board as well
    • Cut the plastic down into 6”x6” squares
      (this final frame outer dimensions is totally arbitrary. For me, I decided these could also be used with my 90mm lens on my 4×5 as well as with the pinhole)
    • Decide how large the interior hole should be (just like making a matte)
      I decided on 4.5”x4.5”
    • Measure from the center out
    • Mark with a pencil or gel pen
    • Cut out the center square
      You should now have a “frame” that is 6”x6” on the outside with a center cut hole that is app. 4.5”x4.5”
    • On one side of the frame, place double stick tape around the entire edge.
  4. Lay one of the gel sheets down on a flat surface
  5. Place the frame, tape side down on top of the gel – making sure that the gel is flat and doesn’t crimp or fold
  6. Trim the “framed” gel out of the larger sheet.
  7. Continue until you have a framed gel for each color you have

It is a good idea to make two or more of the lighter colors in case you want to double up the gel for added color effects or filtering.

Costs

  • Rosco gel sheet – $5.95 sheet
  • Plastic sheet for frames – $4.95 sheet
  • Double stick tape – $2.99 roll

Once you have a complete set, stick in an envelope or Ziploc and keep flat between two pieces of board for protection and take with you in your camera setup.

In the Field

In the field, after choosing my location and then setting up my camera, I shot a control sample to confirm my exposures and the exact composition. Most of my images use exposure times longer than 30 seconds. To use the filters, I use a shutter release on my camera, set it to open, and then hold the filter in front of the pinhole while counting my exposure time. In general, the 1/2 second or so with no filter didn’t seem to make a difference.

No Filter Filter Light Amber
Landscape
Type 79
No Filter
The blue sky looks fairly true but there is no separation in any of the foliage. The color shift takes everything green.
Landscape
Type 79
Filter Light Amber
The Light Amber doesn’t have much effect on the color in this scene.
Filter Medium amber Filter Tough Minus green .5
Landscape
Type 79
Filter Medium Amber
This filter, being on the orange side, would be expected to counter the green, but instead it just turns everything amber.
Landscape
Type 79
Filter Tough Minus Green .5
I found the Tough Minus Green to be the most effective at countering the green shift effect from the reciprocity failure. The filter is light lavendar in color.
Filter Light Red Landscape
Type 79
Filter Light Red
This filter produces an interesting and otherworldly effect but does nothing to correct the color to a more “true” appearance.

In some of the examples, I doubled the filters up together—sometimes the same filter color and in a couple of instances two different colors. If filters are doubled or are darker, then the exposure should be increased accordingly. I doubled the exposure for the darkest filters.

Make sure that if you double filters, that they are held tightly together to avoid any light reflection from one gel to another throwing light effects into your image.

Conclusion

I think this technique seems to work although I am still experimenting with which filter gives me the “best” color correction for each type of film. Some of it is personal preference and some depends on the composition, the lighting and the mood I am trying to achieve.

The Pros: It is definitely much cheaper and easier to experiment with than traditional filters. Making your own also allows for use with any size camera or lens.

The Cons: The gels scratch easily and can be difficult to hand hold in windy situations. Extra care also must be taken to avoid light refraction if the gel isn’t perfectly parallel to the film and lens planes.