GND8 3 f-stop Graduated Neutral Density Filter - K&F Concept
An elegant solution to mount filters on your lens without necessarily resorting to expensive and impractical screw filters (you should have a complete set for each lens of your photographic kit) is to use an external neutral density graduated ND filter. These filters are typically rectangular in shape, with a light half and a dark half and a transition area in between. You can often choose between a hard or soft transition between the light and dark half: in general, hard transitions are better for landscapes with relatively flat horizons, while soft transitions are better for scenes where the horizon is interrupted from hills, trees or buildings.
Most of the ND gradations are designed to be inserted in support of housing "rectangular" filters. The mount attaches to the front of the lens via a screw adapter ring. Since the filter is rectangular rather than square, it is possible to move it up and down inside the support, allowing you to position the vertical transition between light and dark to adapt to the composition. There are some gradual circular ND filters on the market, which screw directly onto the thread of the lens filter attachment; they are a bad substitute, however, given that you are stuck with the position of where the transition falls, which can become a limiting factor when composing the shots.
Rectangular filters, as we said, need a fixing ring, which is screwed into the fixing filter of the lens filter. Of course, you will need more adapter rings if you want to use your filters with a variety of lenses with different threads.
The adapter
As for the mounting system, this is in turn made up of two components: the actual frame, made of steel and very robust, and the ring to screw it to the lens. Just to make the product usable on various lenses, the K&F Concept provides 7 adapters (52mm / 58mm / 62mm / 67mm / 72mm / 77mm / 82mm), able to cover different needs. In any case, we had already talked about it here.
The filter holder and adapter rings are made of metal and are very robust. For the purpose of this test, I screwed the 77mm adapter ring onto the lens. To fix the metal support to the adapter ring there is a very useful release button of the metal closure to be pressed. The ring of the adapter ring is positioned under two small closures, the button is pressed and the closure opens and closes above the ring, fixing it firmly.
Once it was securely fixed I tried to push the adapter ring away by force and it was not possible to do it. This means that it does not come off, which is very good. To release the adapter ring from the holder, you press the same release button and the adapter ring comes off quickly and easily even when attached to the camera.
Quality of K&F ND8 graduated filter
When it comes to K&F products, there is normally little to say in terms of quality: this brand has been able to gain a place of honor in the field of photographic accessories, both as regards the supports (bags, stands, stands) both as regards filters and accessories for lenses.
The construction quality has now reached levels of excellence without equal (this filter, for example, was made in German laboratories), with products free from visible problems and which allow to obtain perfect images.
The filter in question has nothing to envy to the more expensive alternatives, such as the Cokin. In addition, the same filter is delivered in a beautiful faux leather case, resistant and able to protect the filter while on the move.
The only drawback, which is common to all these types of filters, is the problem of fingerprints: being all surface, handling it without leaving fingerprints is not possible. Hoping that someone will invent finger-proof glass in the future.
Specifications of GND8 Graduated Filter
- 3-stop ND8 (0,9) graduated filter made in Germany, able to offer greater optical clarity and chromatic fidelity compared to the competition.
- Nano waterproof coating, scratch-resistant, green anti-reflective coating, effectively prevent oil, fingerprints, scratches.
- The neutral density K & F glass adopts exclusive gradual coating, the ultraviolet light in the light of the near-infrared can pass through it in a completely uniform way.
- The double optical side that allows to ensure high optical parallelism and therefore the high sharpness of the image
- Dimensions: 100mm * 150mm * 2mm
- 20 layers Double-layer nano-coating
- Water-repellent / oil-proof / dust-proof / anti-soil / scratch-resistant / scratch-resistant
- Very high-quality glass
- Low reflectivity (less than 1.5%)
- Waterproof and antifouling surface
- no vignetting effect
- High light transmission
- Multilayer coating