All the photographer should know that there is a kind of lens, which can make the background of the photos have a dreamy doughnut effect. This kind of filter is what we usually call a mirror filter.

Canon1DX Mark II 、f2.8、ISO：50、EV：-1、200mm

As known to all those who have used the mirror lens, the traditional mirror lens only has one aperture stop and can only focus manually. It is very inconvenient to use . Moreover, good quality mirror filter is expensive and the cheap price cause poor image quality . 

Canon1DX Mark II 、f8、ISO：1000、EV：-0.7、500mm

Image captured by mirror lens.

Canon1DX Mark II 、f8、ISO：1000、EV：-1.3、500mm

Image captured by mirror filter.

Canon1DX Mark II 、f8、ISO：1000、EV：-1.3、500mm

Image captured by mirror filter.

These three photos are the best three, which were shot with mirror lens in an afternoon time. Because of the manual focusing, many photos are not in focus.

Now, Let's see the effect of the photos by shot with the Kase mirror filter.

For evaluating the effect of the mirror filter, we choose 3 kinds of lens for testing. 

The gear we used: 

camera: Canon1DX Mark II 

lens: Canon 100-400mm F4.5-5.6, Canon 70-200mm F2.8, Canon 24-105mm F4

let's compare by using Canon 100-400mm F4 .5-5.6.

Canon1DX Mark II 、f5、ISO：250、EV：-1、300mm

Perfect doughnut boken effect by using the mirror filter.

Canon1DX Mark II 、f5、ISO：250、EV：-1、300mm、

Only normal light spots by shot without the mirror filter.

Canon1DX Mark II 、f5、ISO：250、EV：-0.3、300mm

The effect by using the mirror filter.

Canon1DX Mark II 、f5、ISO：250、EV：-0.3、300mm

The result without using mirror filter

Canon1DX Mark II 、f5.6、ISO：250、EV：-0.7、400mm

The effect by using the mirror filter.

Canon1DX Mark II 、f5.6、ISO：250、EV：-0.7、400mm

The result without using mirror filter

From the comparison of the effect by using 100-400mm f4.5-5.6 lens, the performance of the mirror filter is perfect.Let's see how is the performance on f Canon 70-200mm f2.8 lens?

Canon1DX Mark II 、f2.8、ISO：50、EV：-1、200mm

The doughnut bokeh is also good, by using the mirror filter.

Canon1DX Mark II 、f2.8、ISO：50、EV：-1、200mm

the boken is normal without mirror filter

Canon1DX Mark II 、f2.8、ISO：50、EV：-1、200mm

The effect by using the mirror filter.

Canon1DX Mark II 、f2.8、ISO：50、EV：-1、200mm

The result without using mirror filter

From the comparison of the effect by using 70-200mm f2.8 lens, the performance of the mirror filter is perfect.Let's see how is the performance on f Canon 24-105mm f4 lens?

Canon1DX Mark II 、f4、ISO：50、105mm

It has a obvious issue by using the mirror filter on 105mm lens. Focusing is very difficult. This is the best one which has a little doughnut effect bokeh.

Canon1DX Mark II 、f4、ISO：50、105mm

There is the other issue of the mirror filter on the 105mm lens. A black shadow in the middle of the picture, so it is not recommended to use the Mirror filter on the 24-105mm F4 lens.

Next, we used a 70-200mm f2.8 lens and tested it with different apertures. Let's see the test results.

Canon1DX Mark II 、f2.8、ISO：50、EV：-1、200mm

The mirror filter on 70-200mm f2.8 lens, the effect of f2.8 aperture.

Canon1DX Mark II 、f2.8、ISO：50、EV：-0.3、200mm

The mirror filter on 70-200mm f2.8 lens, the effect of f3.2 aperture.

The mirror filter on 70-200mm f2.8 lens, the effect of f5.6 aperture.

The mirror filter on 70-200mm f2.8 lens, the effect of f9 aperture.

According to the comparison of the 4 photos, the doughnut effect bokeh is great when the aperture is 2.8, 3.2 and 5.6. When the aperture is smaller than f5.6, the black shadow begins to appear in the center of the picture. 

The results of the evaluation by using three kinds of lens:

1. The mirror filter performs perfectly on the medium-telephoto lens, and it is recommended. It is not recommended for 24-105 lenses;

2. Use a large aperture on the medium-telephoto lens, and as large as possible. It is recommended to shoot with an aperture larger than or equal to F5.6.

The advantages and use tips of Kase Mirror filter:

1. The price is cheaper than mirror lens.

2. Installation is as convenient and simple as installing a UV mirror.

3. Autofocus can be achieved, which improves shooting efficiency and shortens the focusing time;

4. It can be used on the original high-quality lens, which improves the picture quality of the work;

5. you need to remove the UV filter on the lens when using the mirror filter;

6. It is easier to focus by using the center point and single point focusing. It is recommended to focus on the center point first and then press the shutter halfway torecompose the shot;

7. It is recommended to use aperture priority mode for shooting, and it is recommended to use large aperture shooting as much as possible;

8. The effect obtained on the telephoto lens can be more obvious;

9. Shooting same effect as the mirror lens. You must choose side backlighting or backlighting when shooting. The doughnut effect can only appear when the background has water drops or light spots;

10. The mirror filter is suitable for shooting lotus flowers, other flowers can also be photographed by the same principle. there are also has good effect when shooting night scene portraits.