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Super 8 & the “T” – Beginner’s Guide to Tungsten Film, Built‑in 85 Filters & Cartridge NotchesUpdated 5 hours ago

If you have ever wondered why some Super 8 film stocks end with the letter “T”, or what that tiny orange filter icon on your camera does, you have come to the right place. This guide demystifies tungsten‑balanced film, colour temperature, and the clever cartridge‑notch system that makes the Super 8 format so beginner‑friendly.

1. What Is Colour Temperature?

Different light sources emit light at different colour temperatures, measured in Kelvin (K). While our eyes adapt automatically, film sees these differences very clearly.

Light sourceApprox. temperatureAppearance
Bright daylight5,500 KBlue‑white
Overcast sky6,500 K+Cool blue
Tungsten bulb3,200 KOrange‑yellow
Fluorescent lampVariesOften green
Candlelight1,900 KDeep orange


2. Why the “T” Appears on Super 8 Film Boxes

The “T” stands for tungsten‑balanced film. Stocks such as Kodak Vision3 500T are designed to look neutral under warm, 3,200 K tungsten light. Shoot them outdoors in daylight and everything shifts noticeably blue unless corrected.


3. Kodak’s Clever Fix: the Internal 85 Filter

When Super 8 debuted in 1965, most holiday footage was shot outdoors with tungsten stock. Kodak solved the colour‑shift problem by fitting a tiny Wratten 85 orange filter inside almost every Super 8 camera. Engage the filter for daylight, disengage it for indoor tungsten light—simple and fool‑proof.


4. Cartridge Notches: How Your Camera Swings the Filter

Flip your cartridge over and you may see a small rectangular filter notch. This simple bit of plastic tells the camera whether to leave the internal 85 filter in place or park it out of the light path.

Cartridge typeNotch present?Internal 85 filter actionResult
Tungsten‑balanced (200T, 500T, 800T)YesFilter stays inTungsten film records daylight correctly
Daylight‑balanced (50D, 100D)NoFilter swings outDaylight film records colours naturally


5. The Hidden Cost: Exposure Penalty

The internal 85 filter absorbs roughly ⅔ stop of light. For instance, 500T metered at 500 ASA behaves more like 320 ASA when the filter is engaged. Most modern cameras compensate automatically, but older models may not—so be ready to open up or rate the film slower.


6. A Typical Outdoor Scenario

  1. Load Vision3 500T in bright daylight.
  2. The cartridge notch engages the 85 filter.
  3. Colour balance is neutral, exposure is ⅔ stop slower.
  4. Forget to disengage the filter indoors and shots under tungsten bulbs turn orange.


7. Manual Filter Switch & When Built‑In Filters Fail

Ageing plastic

Many original 85 filters were acrylic; time, heat and dust can yellow or craze them, softening sharpness.

Modern options exist

Daylight stocks like 50D mean you no longer need to rely on tungsten film plus an internal filter outside. For ultimate clarity, tape the filter switch to “out” and use a fresh glass 85 screw‑in filter only when required.

8. Quick Reference Tables

Lighting situationFilm & filterExposure tip
Bright daylight50D or 500T + 85 INMeter at box speed
Overcast / golden hour50D or 500T + 85 INOpen ½–1 stop
Indoor tungsten lamps500T, 85 OUTMeter at box speed
Mixed night street / neon500T, 85 OUTAccept slight casts, fine‑tune in grade


9. Tips for Stress‑Free First Rolls

  • Start with daylight film outdoors. No notch means no filter—zero settings to forget.
  • Label your filter switch. A small “IN/OUT” sticker prevents mistakes when light changes fast.
  • Watch the ISO loss. Tungsten + 85 outdoors? Rate 500T at 320 ASA or open ⅔ stop.
  • Inspect the filter glass. Torch through the lens port; haze or scratches invite an external replacement.
  • Relax—scans are forgiving. Labs can rebalance modest blue or orange shifts in post.


10. Creative Approaches to Colour Temperature

Rules are there to be bent. Shoot tungsten film in daylight without correction for an icy, futuristic blue. Use daylight film under tungsten bulbs for romantic amber scenes. Your colour choices become a storytelling tool.


11. Putting It All Together

Think of the internal 85 as orange sunglasses that automatically pop down whenever a tungsten cartridge drops into the camera. The cartridge notch is the handshake that says “I’m tungsten—leave the sunnies on”. Remove the notch (or flip the switch) and the sunnies come off. Master this notch → filter → colour relationship and you have solved 90 % of beginner Super 8 headaches.

Ready to shoot your first reel? Explore our motion services here or drop by the lab for advice.

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