PureNight Premium Light Pollution Reduction Filter by Lonely Speck

Lonely Speck PureNight Light Pollution Reduction Filter

PureNight Now in Production (Crowdfunding Successful!)

Enjoy better night sky images straight out of camera with PureNight.

PureNight is a premium glass light pollution reduction filter designed by Lonely Speck. Made of a special didymium glass, PureNight reduces the transmission of light from sodium vapor lamps, one of the most prevalent sources of light pollution on our planet. Resulting images will have truer colors and improved contrast when compared to images influenced by light pollution.

Lonely Speck Pure Night Light Pollution Filter

85mm PureNight Filter mounted via the Formatt-Hitech 85mm Filter Holder. Please note that production versions of PureNight may differ from our prototype shown here.

Early Bird Backing

85mm: 110% funded

100mm: 556% funded

150mm: 120% funded

Limited Run. PureNight is now in production. A limited quantity of 100mm filters are still available for pre-order below. The 85 and 150mm filter pre-orders are sold out.

Sample Images

Below are example photos taken with and without the PureNight installed.

These photos were made in Tekapo, New Zealand, home of the world’s largest dark sky reserve and some of the darkest skies in the world. Even so, PureNight makes a dramatic improvement by reducing the effects of light pollution on the image.

Lonely Speck PureNight Light Pollution Reduction Filter Example Without Filter Lonely Speck PureNight Light Pollution Reduction Filter Example With Filter

Both of these photos were exported straight from RAW files with no edits whatsoever. A one stop increase in ISO was used on the filtered image to compensate for the decrease in brightness in the overall image due to the reduction of light pollution. All other settings were identical. First image: Sony a7S, 18mm f/2.8, 25s, ISO 3200, Daylight WB. Second image: Sony a7S, 18mm f/2.8, 25s, ISO 6400, Daylight WB. You can download the full resolution RAW images here (.zip, 24.1 MB). They’re in DNG format so they should be editable on most RAW editors like Adobe Lightroom or Camera RAW.

More Comparisons

By popular request, here are a couple more comparisons of astrophotos shot with and without the PureNight.

lonely-speck-pure-night-light-pollution-reduction-filter-example-alabama-hills-no lonely-speck-pure-night-light-pollution-reduction-filter-example-alabama-hills-with

These photos, as with the first samples, were exported directly from RAW with no edits other than a brightness equalization with a 0.7EV push on the PureNight shots to compensate for the reduced brightness of the light pollution. We expect the final versions of PureNight to show roughly -0.3EV to -1EV of reduction in brightness, depending on the conditions.


Once again, If you would like to download the full resolution versions of these images to play around with, download the full resolution RAW DNGs here (.zip, 73.2 MB).

How It Works

PureNight is made of a special type of glass called didymium glass. It mounts in front of your camera lens with a standard square filter holder (sold separately).

Didymium glass greatly reduces transmission of yellow and orange light in the 575nm to 600nm wavelengths, the same wavelength of light that is emitted by high pressure sodium vapor lamps. Sodium vapor lamps are most commonly used on street lights and industrial lighting fixtures and so they are one of the most prevalent sources of light pollution for astrophotography.


Our PureNight filter will reduce the effect of light pollution in your astrophotography for truer colors straight out of the camera. Photos made through the PureNight will have improved contrast and reduced haze from light pollution.

Premium Optical Quality

PureNight is precision ground and polished and features an anti-reflective multi-coating to greatly reduce the effect of internal reflections and ghosting that plague most filters when used at night with bright light sources in the image.


Mounting PureNight

PureNight is a universal square filter available in 85mm and 100mm sizes. PureNight requires a square filter holder and the appropriately-sized system adapter ring to fit your lens (see recommendations below).


Like the SharpStar2, PureNight is made to fit into the most popular square filter systems in 85mm, 100mm and 150mm sizes.

If you don’t already have a filter system, here are some recommendations:

85mm (lenses up to filter diameter of 77mm):

Formatt Hitech 85mm Aluminum Holder (Amazon / B&H) and Formatt Hitech Adapter Rings for 85mm Aluminum Holder (Amazon / B&H)

100mm (lenses up to filter diameter of 105mm):

Formatt Hitech 100mm Aluminum Modular Holder (AmazonB&H) and Formatt Hitech Adapter Rings for 100mm Holder (Amazon / B&H)

150mm  (certain wide angle lenses with fixed hoods):

Haida 150mm Filter Holder (Amazon / B&H)
Lee SW150 Filter Holder (Amazon / B&H)
NiSi 150mm Filter Holder (Amazon / B&H)

We’re fully funded and scheduled to start shipping April-May 2017!

We launched PureNight as a crowdfunded project with a close date of December 31, 2016 for our early bird pre-orders. Thank you to all of our supporters so far!

Early Bird customers (ordered by Dec. 31, 2016) received a discount on their order, and their orders will be the first to ship!

Each PureNight filter is custom made to our specifications. Grinding, polishing, optical coating, engraving and packaging are all things that we need to be able to order in a large enough quantity to make PureNight reasonably affordable. We were successful in crowdfunding our last project, the SharpStar and we’re happy that PureNight has proven successful as well!

Pre-Order Now, Limited Quantities Available

UPDATE: April 17, 2017: Limited quantity of 100mm pre-orders available. 85mm and 150mm pre-orders sold out. Estimated shipping on new orders: May 2017.

We’re fully funded and scheduled to begin fulfillment in April. Early Bird Backers: We will send periodic updates to the email address you provided when you placed your order. If you have any questions or concerns or wish to cancel your order, please don’t hesitate to contact us.

Sizes available:

85mm square filter — $249 — SOLD OUT

(Compatible filter systems: Cokin P, Formatt-Hitech 85mm)

100mm square filter — $269 — SHIPPING MAY 2017

(Compatible filter systems: Lee 100, 4″x4″, Formatt-Hitech 100mm, Cokin Z-Pro)

150mm square filter — $399 (Early Bird Pricing) — SOLD OUT

(Compatible filter systems: Lee SW150, NiSi 150mm, Haida 150mm)

100% Product Guarantee

If you’re not satisfied with your order for any reason, contact us and we’ll make it better with a free replacement or return for a refund.

Your order will include:

  • PureNight Light Pollution Reduction Filter
  • Protective Case

NOT included: filter holder and adapter ring (sold separately, see recommendations above)

PLEASE NOTE: This is a Pre-Order. Please see estimated shipping dates below. You will be charged when you place your order. Cancel anytime before shipment for a full refund by emailing us.

Estimated Shipping Dates:

  • orders placed by Dec. 31, 2016: estimated shipping in March 2017 (no longer available)
  • current 85mm pre-orders: estimated shipping in April 2017 (sold out)
  • current 100mm pre-orders: estimated shipping in May 2017
  • current 150mm pre-orders: estimated shipping in May 2017 (sold out)

Email updates regarding the status of this campaign will be sent to the email address you provide when you place your order.


*All orders are currently processed through Celery. (This name may appear on your charge approval.) Credit cards (via Stripe) and PayPal are both accepted forms of payment.

PureNight orders will usually ship via USPS First Class Mail. Tracking may not be available for certain international destinations.

Questions? Check out our PureNight FAQ