The Hoya SQ100 Starscape Filter for Hoya Filter Holder Systemfrom Hoya SQ100 Starscape Filter for Hoya Filter Holder Systemcuts out light pollution that comes from city lights by reducing visible light spectrum wavelengths associated with mercury-vapor and sodium-vapor sources. These types of lamps are common to most cities world-wide and are usually associated with light pollution. Yellowish and greenish colors are reduced, allowing the night sky's colors to appear clearer and more natural.

For Hoya Sq100 Filter Holder System    100 x 100mm, 2mm Thick    0.5-Stop Exposure Increase    Chemically Reinforced Optical Glass    IRND Nano Coating to Minimize Color Cast    Reduces Light Pollution in Night Sky    100 x 100mm, 2mm Thick

Related Questions and Answers

Q: 1. Will this filter work with the Sensei step-up ring? 62mm-67mm to be precise.

A: I haven't tried it but I imagine it would.

Q: 2. would it work with other filters???

A: Yes, this filter can stack onto other filters. You will want to mount the Cir/Pol filter last, so you can utilize the polarization effect.

Q: 3. Why won’t this filter tighten on my lens? It’s a 62mm and that what my lens takes.

A: The loose portion is the adjustment ring for polarization. Otherwise the filter will fit tight to your filter thread on the lens.

Q: 4. I know that to use this filter on my Minolta X-700, I'd need to expose an additional 1 to 1 stops for pictures to turn out correctly. I'd like to use this filter for a Pentax K-500 Digital Camera. Would I need to many any stop adjustments like I would my Minolta? Thanks & Happy Thanksgiving!!!

A: Yes, any circular polarizer will add stops to the exposure, it depends on the polarizer as to how many stops are added.

Q: 5. I’ve read this is the USA version of the Hoya Starscape filter, is that true? Or is there a difference with the Starscape from this model?

A: YEs this is the USA version of the filter.

Q: 6. I'm considering using this filter on a canon EF 16-35mm f/4L IS USM lens mounted on a Canon 6D body. Will the depth of this filter's frame result in any vignetting in the images taken at the lens's widest angle of view (16mm)?

A: I see no vignetting with when this filter used at f/4 on nikkor 16-35mm 1:4g ed lens

Q: 7. Is this polarizer good for beach photos? Thanks!

A: I used this filter in the snows of Patagonia, the beaches of Argentina, the waters all about the Scotia circle and all about Antartica and surrounding waters and ice. Good job.

Q: 8. What is the proper technique for attaching the filter to the filter threads on the front of the lens? The filter is very thin, with very little to grip, but is further rendered difficult to screw on by the presence of the rotating section of the filter. Basically you can only hold the rotating part so it is tough to get the threaded portion to turn and screw into the threads on the lens. The rotating part just rotates so you can barely get any torque on the threaded portion. I finally got mine to screw in by pushing firmly toward the lens as I turned the filter. I don't want to damage anything. When using this technique the threaded portion turns slowly because it drags more on the lens threads.

A: Since submitting this question, I had a chance to look closely at the filter with my OptiVisor. It seems there is a very thin knurled ring on the threaded part of the filter just below the rotating part. I will have to practice and see if I can master threading it to the lens without cross threading or otherwise damaging anything. I do have a filter wrench, but the threads are so fine and delicate that it is even more difficult to tell if you are crossthreading. That will take some practice, too. The lens filter threads are inside a metal ring of sorts that prevents full sized fingers from being able to grip that knurled surface enough to be able to turn the ring to thread it in.

Q: 9. What size lens do this filter fits?

A: Hoya 72mm NXT Circular Polarizer Filter will fit on any lens with a 72mm front diameter with threads. The filter front ring is also the same size and you can attach your lens cap on the filter.

Q: 10. What material is the metal?

A: They are made of aluminum.