With the “Starburst 6-point filter” I expected the typical, very high quality of “K&F CONCEPT” accessories... and was not disappointed.
For me, it is the 82 mm version.
The frame is made of high-quality aluminum and is made of 2 parts. In total, even 3 pieces.
It consists of a base frame with a total diameter of 85 mm. This has a high-quality, uniform and very handy knurling on the outside. The thread is located in front of knurling. Here with 82 mm diameter and 2.5 mm depth for screwing into lenses, or other accessories such as adapter rings.
The front part is the holder for the filter glass. Also equipped with an 85 mm outer diameter and an 82 mm thread on the front to accommodate further filters. The filter glass is not glued, but is screwed to the third aluminum part, a narrow ring. This leaves a thread depth of 2 mm to accommodate further accessories. The front ring is smooth on the outside, but has two opposite handle knurls that even extend beyond the outer diameter.
This makes it possible to rotate the front part of the filter intuitively and very sensitively.
In this way, the direction of each of the 6 rays can be adjusted as desired.
The filter parts run very softly and evenly with exactly the right resistance to each other. This allows an exact adjustment without the filter adjusting itself.
All threads are first-class and fit very well. The filter can be accurately screwed into both my lenses and stepdown rings. Other 82 filters fit easily on the front.
The matt black coating has so far proven to be very scratch-resistant and looks professionally elegant.
The aluminum frame is only 7.5 mm thick and weighs 22 g. Minus the 2.5 mm screw-in thread, the filter is assembled 5 mm and is therefore also suitable for wide-angle lenses.
The optical glass also looks and works of very high quality.
At this point, we rely on 18 times the compensation. In any case, the surface is low-reflection. It is not sensitive to fingerprints or light dirt and is very easy to clean.
Drops of water do not stick to the glass and bead off.

The filter creates a 6-pointed star from bright point light sources in the image! This depends on many factors but usually looks very consistent.
Thanks to the fully rotatable filter frame, the direction of the six-pointed star can be adjusted.
A very effective, high-quality filter is used sparingly and purposefully.
As an express effect filter, it naturally also changes the imaging performance of lenses, but unwanted effects are not noticeable.
A highly recommended filter for special applications. With the 82 mm version and step-down rings, it is suitable for many lenses.

Using and shooting with the filter is really fun and 5 stars are well deserved.