The Blackmagic Design Spares - Camera CC6K - OLPF refers to the Optical Low Pass Filter assembly. It is important to distinguish between the original Pocket 6K (G1) and the newer 6K G2 / 6K Pro / 6K Full Frame, as Blackmagic changed the OLPF design significantly between these generations.
In digital cinema, the OLPF is a specialized glass stack that sits in front of the sensor to reduce Moiré (strange patterns on fine textures like fabrics) and Aliasing (jagged edges).
1. The Original Pocket 6K (G1)
The original 6K (G1) did not come with a built-in OLPF from the factory; it only had a standard IR-cut filter.
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The "Spare" Part: Most users seeking an "OLPF" for the G1 are actually looking for the IR-cut filter replacement or a third-party modification kit (like Rawlite).
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Replacement Need: You typically replace this if the original glass is scratched, oxidized (showing a "cloudy" or "magenta" tint), or if you want to upgrade the camera’s ability to handle fine patterns.
2. Pocket 6K G2 / 6K Pro / 6K Full Frame
These newer models were designed with a more modular "turret" system, making the filter assembly much easier to service or swap.
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The Assembly: On these models, the OLPF/IR-cut stack is housed in a matte black cylinder (the turret) inside the EF or L-mount.
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User-Serviceable: Blackmagic designed these to be replaced by loosening just three screws inside the mount. You do not need to open the camera chassis to access this part.
When to Replace the OLPF
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IR Contamination: If your "blacks" are turning brown or reddish under sunlight or tungsten light, the IR-cut coating on the OLPF glass has failed.
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Physical Scratches: Any mark on this glass will be visible in your footage, especially when stopping down the lens (e.g., $f/11$ or $f/22$).
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Coating Delamination: In humid environments, the multi-layer coatings can "bubble" or peel, creating a hazy look in your images.
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Moiré Issues: If you are shooting for broadcast or high-end commercial work where fine patterns are common, you may need to replace a damaged OLPF to maintain professional image standards.
Technical Installation (6K G2 / Pro / FF)
Repair Level: 2 (Moderate). 1. Turret Removal: Use a precision Phillips head screwdriver to remove the three screws inside the lens mount.
2. Extraction: Carefully lift the matte black turret out using plastic tweezers.
3. The Glass Swap: The OLPF/IR glass is held in place by another set of small screws or a retaining ring.
4. Flange Focus (Shimming): Critical Note. OLPF glass has a specific thickness that affects where the light hits the sensor. If you replace the glass with a different thickness (common with third-party OLPFs), you must add or remove shims behind the lens mount to ensure your lenses still hit "Infinity" focus correctly.
Identifying the Part You Need
| Camera Model |
Filter Type |
Ease of Repair |
| Pocket 6K (Original) |
IR-Cut Only (No OLPF stock) |
Moderate (Requires tweezers) |
| Pocket 6K G2 / Pro |
Combined OLPF + IR-Cut |
Easy (Turret system) |
| Cinema Camera 6K (FF) |
Combined OLPF + IR-Cut |
Easy (Turret system) |
Expert Advice: If you are seeing "dust spots" on your image, always try a professional sensor swap/wet clean first. What looks like a scratch on the glass is often just a streak of oil or a stubborn dust particle that a blower can't move. Only order the replacement if a wet clean fails to resolve the mark.
Are you looking to replace a damaged original filter, or are you trying to install an aftermarket OLPF to reduce moiré?
