Sigma LPT-21 vs PUV-21: Which Lens Filter to Buy
By TRM | Published: 2026-11-02
Category: Buying Guides
Compare the Sigma LPT-21 clear protector and WR Protector UV PUV-21, with practical rules for choosing between 95mm and 105mm protection filters.
Quick answer
Choose the Sigma Filtre Protector LPT-21 (95mm) if you want neutral, no-color-shift protection for a lens with a 95mm front thread. Choose the Sigma Filtre WR Protector + UV PUV-21 (105mm) if your lens takes 105mm filters and you want UV absorption to reduce the blue cast that can appear in daylight.
Clear protection versus UV absorption
The main difference between these two Sigma filters is what they do to the light. The LPT-21 is a clear optical glass protector with no effect on exposure or color reproduction, so it stays out of the way of your image. The PUV-21 also protects the front element, but adds UV absorption to reduce the bluish cast that can show up in daylight.
That makes the PUV-21 more useful when you shoot outdoors in bright conditions and want a small correction baked in. The LPT-21 is the more neutral choice when you already control color in camera or in post and prefer a filter that changes nothing.
Thread size decides first
These two filters are not interchangeable. The LPT-21 is a 95mm filter and the PUV-21 is a 105mm filter, so the deciding factor is the front filter thread of your lens. Check the thread diameter printed on the lens barrel or in its specifications before comparing anything else.
If you own lenses with different thread sizes, buying the wrong diameter means the filter will not mount at all. Match the filter to the lens you plan to protect most often, then treat the clear-versus-UV question as the second decision.
When the price difference matters
The LPT-21 is listed at USD 85.68 against a comparison price of USD 124.17, while the PUV-21 is listed at USD 135.49 against USD 190.83. The PUV-21 costs more, which is reasonable given its added UV absorption, but only if you actually want that effect and your lens takes 105mm filters.
Do not pay extra for UV absorption you will not use. If your work is mostly controlled lighting or you prefer to handle color in post, the clear LPT-21 is the simpler and cheaper route.
Decision rules for buying
- Check the thread size first: Measure or look up your lens front thread. Buy the LPT-21 only for 95mm lenses and the PUV-21 only for 105mm lenses; a mismatch means the filter will not fit. Write the thread size down before you shop so you do not compare filters that cannot mount on your lens.
- Decide on UV absorption: Choose the PUV-21 if you often shoot in daylight and want to reduce a blue cast in camera. Choose the LPT-21 if you want a filter that leaves exposure and color untouched.
- Weigh the cost against the added function: The PUV-21 costs more than the LPT-21. Pay the difference only if you need UV absorption and have a 105mm lens; otherwise the clear LPT-21 covers protection at a lower price. If you own both 95mm and 105mm lenses, buy for the lens you use most rather than splitting the budget across two filters.
Product facts
- Sigma Filtre Protector LPT-21 (95mm): Clear optical glass protector with no effect on exposure or color reproduction. You can leave it mounted during a shoot without changing your exposure or color, which suits a neutral, set-and-forget protection strategy.
Sigma Filtre Protector LPT-21 (95mm) - Sigma Filtre WR Protector + UV PUV-21 (105mm): Protection and UV filter in clear optical glass that absorbs ultraviolet light to reduce the bluish cast that can appear in daylight. It gives you both front-element protection and a small daylight color correction in one filter, which can simplify outdoor shooting.
Sigma Filtre WR Protector + UV PUV-21 (105mm)
Who should buy which
Best for
- Shooters with a 95mm lens who want neutral front-element protection without color shift
- Video and photo work in controlled lighting where color is handled in post
- Buyers who want a lower-cost protector filter
Not for
- Lenses with a 105mm front thread, which need the PUV-21 instead
- Shooters who specifically want UV absorption in daylight
