Smoked Plexiglass

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Smoked Plexiglass

Joined: 03 Dec 2016, 18:53

17 Dec 2016, 06:24 #1

In reviewing the tint and hue of the original TOS bridge displays, the color of the displays are dependent on many things.
I am starting this thread in order to evaluate the specific characteristics of the tinted glass that is used on the front of the displays.

The color of the images is a function of the intensity of the light source, the white diffusing plastic sheet behind the graphic, the colored filter behind the graphic, and the characteristic of the smoked glass.

In order to correctly evaluate the specific colors used on the display, I'm starting this thread so that I can post metrics on screen grabs from the TOS-R episodes.

I'd like to first see if the colors of the displays change between Season 1 and Season 3.  They may have some change due to the change in the film stock and processing techniques of the color when being digitized.
Another test is to compare the display color for the same display but in different shots.  The smoked glass covering the front of the display may diffuse light and color differently depending upon the exact camera angle being used.  In order to evaluate changes in color due to changes in the camera's angle, the color of specific displays and graphics thereon can be screen grabbed and then quantified.

As I do estimates, I will archive a screen grab and then discuss the color of a display in a specific episode.

My guess is that we will see slightly color intensity differences between seasons and between camera angles.  This difference will be interesting to quantify because the color of the displays that we see today in the TOS-R episodes may reflect artifact from the film stock, the camera angles, and digital processing.

Joined: 03 Dec 2016, 18:53

17 Dec 2016, 06:47 #2

The above discussion has relevancy to the selection of the correct tint of "smoked plexiglass".
In looking for current supply sources of this particular element, manufacturers have varying gradations of tint.
It's necessary to quantify the correct tint gradation in order to have the colors end up correctly being visualized.
There is an interesting nuance here.
If you are in person and looking at the display, the displays may have significant difference in color tone and look.
The human eye sees color differently than film stock.
Passing 35mm film stock through standard definition TV recording and/or TOS-R production would create different colors on the displays.
The TOS-R episodes were remastered in high definition. As part of that process, my guess is that the production team would have color balanced the newly digitized scenes.
That color balancing would be automated and likely permit the scene to white balance and color balance accordingly.
Still, the main objective here is to guess at the correct tint.
Perhaps Feek may have insight into the correct tint or gradation of smoked glass?

Joined: 29 Apr 2007, 15:38

17 Dec 2016, 18:19 #3

Regarding the smoke plexi; the link to what I used on the helm restoration is below. I have been building replica displays for years and get pretty good results from the below material. Again, it all depends on the intensity of the light source (and the thickness of the material you use) as to how the colors register through the smoked plexi. The originals actually used smoked glass; not plexi. Here is the link: ... _s/273.htm

Honestly, it is impossible to pin down the exact colors based on screen caps; in person, the colors look nothing like they appear on camera. Even if you are going to try to match the color that they appear on camera there is such variation from episode to episode that at best you could find an average which is what I try to do. The difference in colors between the first and second season when they changed film stock (to a faster film) is staggering. Considering all of the variables including (but not limited to)film stock, color correction processing, reproduction, etc., and you are all over the map. The green color in particular has a wide range because the film did not pick-up that color well (which is why the command tunics appear gold instead of green). I have seen many instance where green appears as almost white but in person these colors were actually a medium green. I can do HD screen grabs of any of the displays from any episode so if you need anything specific; let me know

Joined: 03 Dec 2016, 18:53

18 Dec 2016, 06:08 #4

Dear Feek,

You have already studied the colors and previously noted the differences between seasons and even episodes.

If the colors are changing on the screens fairly significantly, then you are correct to average and make an educated guess.

From the standpoint of the optics involved, the ability of Desilu's film stock to capture the correct color is one issue.  But, there is another issue that I left out.
When you process color film, the chemical process that would develop the film results in the tint and hue / saturation on projection of the printed film.

In considering the issues involved in 1966-1968, most people in the community note that the film stock is the issue.  However, I am now wondering if the color processing is partly to blame as well.  Someone in the archives of the Academy of Motion Pictures may be able to shed more light on the physics and chemistry involved, but I am sensing that the nuances of handling color were new to TV and, likely, Desilu in the 1966 and 1967 seasons.  My guess is that the studio must have bought sufficient quantities of 35mm film to record the masters.

I had heard that 35mm color film was used to make the original master films for TOS.  I've also read (was it your comment here or on FB?) that the original films in the can were 16mm and not 35mm.  If it was 16mm, then I know that the max grain density on 16mm film is about 2K in resolution.  35mm 4:3 aspect ratio film can go to 4K with the right digitalization equipment.

On prior projects, I've contracted with several houses in Burbank and LA to handle this type of conversion work.

When the transfers are done, you can set the white balance of the equipment to translate specific colors on the film to specific colors in the ProRes422 or ProRes4444 file.  However, much of this digital conversion process is a subjective process where the technician's eyes are involved.  If the tech is not good with perceiving color, you can end up with colors looking off.

All this to say that the variable of the colors is intriguing.  We know that the color of the buttons and control panels are not changing.  Therefore, for specific stations, such as the Communications station, sampling the color of the buttons should provide a reference between episodes.

This suggests that measurement of several button colors and comparison to the display colors is wise.

I think I will start with a screen cap from "Turnabout Intruder".

The method that I will follow is:
1.  Make a screen cap from TOS-R "Turnabout Intruder".
2.  Import the screen cap into Photoshop.
3.  Use a digital tool to measure the color of several specific buttons, on a specific control panel, and on a specific station.
4.  Use the same digital tool to measure the color of several graphics on a display screen on the same station in the same screen capture.
5.  Tabulate the specific color data points.
6.  Repeat 1-5 for a different episode with the same station, button, and display.

Joined: 24 Aug 2014, 03:21

18 Dec 2016, 06:57 #5

The film used was absolutely 35mm. 16mm was used to distribute the show in syndication during the 70s and early eighties, before videotape and satellite feeds began to replace that practice in the industry.

Joined: 03 Dec 2016, 18:53

20 Dec 2016, 08:33 #6

Depending upon the quality of the 35mm film stock, it is possible to take a 35mm film master and transfer to 2K or 4K.

Joined: 12 Jul 2013, 04:58

07 Feb 2017, 07:26 #7

The original series was shot on 35mm Eastman Kodak color neg 5251 (ASA 50 tungsten) and then replaced by the new 5254 (ASA 100) in 1968,
this show was filmed in 4-perf 35mm, full gate Mitchell BNC cameras, Academy centered). Finnerman (later Al Francis) also used an Arriflex 2C for hand held shots and shots where the giant/heavy Mitchell camera would not fit (like inside the Jeffries Tube, overhead shots from the studio perm, etc...look for the work "Arri" on the slates)
i had the wonderful luck of meeting with the show's cinematographer, Jerry Finnerman ASC in the 90's and we talked about the show.
one thing he mentioned was that during the first season, they slowly re-faced the bridge display screens with a newly invented item: non-glare glass....Jeffries calls this "architecture glass" in his bridge sketches...Jerry said he requested this as those many screens, faced with highly glossy smoked glass, reflected the studio,lights...and the only remedy at that time (before the non-glare glass) was to stick black construction paper onto the offending screens...which he hated.... But is plainly visible in many shots.
the new non-glare glass was designed for picture frames, and still is. At that time, It was sort of expensive and had to be custom cut per screen, so it was a slow retrofit, starting with the 2 mainly seen bridge stations: Communications & Science.
you can see the slow evolution on this modification during that season.
The non-glare glass eliminated the direct reflection of the studio fresnel lights to camera, and gave a pleasing softness when viewed from off axis, as seen in many of the side shots of Spock at his station.
this glass has no bearing on the color or saturation of the color displays.
another note, the displays were created with black and white high contrast kodaliths and "colored" by motion picture lighting gels. Roscoe is/was the main manufacture of these colored bells, used theatrically as well as in the motion picture/Television industry.
get yourself a few Roscoe Rocolux swatch books and you will find the colors you seek.
these displays often have small enough areas that the art Dept could have pulled the colored gells directly from the swatch books and taped them onto the Kodaliths with the standard black paper tape that we use today.
i am a working cinematographer and use this stuff daily.
Jeff Barklage, s.o.c.

Joined: 29 Apr 2007, 15:38

08 Feb 2017, 01:38 #8

Also in the very earliest episode "The Corbomite Maneuver" they actually would cut squares in the black construction paper so that at least part of the light from the display would shine through while the paper covered the studio light reflections. This obviously was very time consuming and was abandoned almost immediately and they simply covered the entire display. I always find it quite funny to see one of the displays mostly covered but with a random hole cut into it.
Last edited by feek61 on 09 Feb 2017, 11:37, edited 1 time in total.

Joined: 24 Aug 2014, 03:21

09 Feb 2017, 04:22 #9

Great post, Jeff!

Would you happen to know if there was ever a change of film stock for a single episode here and there, for whatever reason? "Friday's Child" comes to mind as one episode that exhibits quite different contrast/density (or something) than surrounding episodes.

Joined: 03 Dec 2016, 18:53

17 Apr 2017, 08:25 #10

Feek - your work is unbelievable in detail and precision.
In reviewing the work of Ubisoft in the new upcoming release of a Star Trek VR game set on the TOS bridge, I hope you get a chance to play that simulator.  It would be really interesting to hear your thoughts and comments on the Ubisoft recreation versus your experience in restoring the original and working the STC sets.

To Scope235 - Thank you so much for your pointer to the Roscoe Rocolux swatch books.  The color elements in the swatch book will help me under the colors.  Since the source of the colors is now understood, the prior screen caps aren't really needed.

Also the pointer to non-glare glass is really helpful.  The on-screen appearance of the TOS displays in Season 3 and in the more modern TV series and films seem to show that the non-glare class is used very commonly on the bridge consoles.  Hollywood must use alot of that stuff!