High- light transmission and excellent- performance Benro PD CPL
With the coming of digital era, software can replicate most filters. However, there is still more than one kind of optical effect that can be achieved only by filters but not by software, for example, to increase saturation in blue skies and white cloud colors, reduce reflections on foliage and rocks and bring out the true colors, especially for those purists who are not willing to do too many dramatic touch ups to the original pictures, like me. Recently, I bought a Benro PD CPL in 77 mm for my trip to Hulun Buir in Inner Mogolia. The filters from Benro (The leading producer of photography accessories in China, who launched its new photography optical filters on 2013 China P&E held from April 19-22 in Beijing. It is said that it took Benro 3 years to the R&D of the filters) has the high quality expected and helped me to yield fabulous images. Now I am going to share my use feeling with you.
Benro 77mm PD CPL-HD WMC
Solid package with built-in sponge
The full name of the purchased polarizer from Benro is PD CPL-HD WMC.CPL (), also called PL filter, allows directionally polarized-light to be absorbed as much as possible. it is often used to eliminate or reduce the reflections or flare by non-metallic surface to bring out the original colors and vivid pictures. According to the different polarizing mechanism, filters are classified into polarizer (LPL). The LPLs are used mainly to MF and the CPL is used to AF and AE.
77mm CPL is compatible with most of the professional cameras
The Benro 77mm PD CPL I bought is compatible with most of the professional digital cameras. The HD means High Definition and WMC means Waterproof Muti-Coating which is also oil repellent, scratch-resistant and fingerprint- proof. Constructed from superior flatness of glass which helps to enhance output sharp images, Benro PD filters adopt rugged black aluminum alloy filter ring. With anodic oxidation treatment, the ring can absorb reflections and prevent exposure from jamming.
EF 70-200mm f/2.8L USM with Benro 77mm PD CPL screwed on
Canon EF 24-105mm f/4L IS USM with Benro 77mm PD CPL screwed on
Blue light reflected by Benro CPL
The above picture is one of the experiments I did to test whether the filter is well water-repellent or not. We can see the water-drop on Benro filter (the left one ) is still plump and has weak adhesion force while the drop on the other filter from Japan (the right one ) has began to spread. After getting rid of the water-drop, we can see the Benro filter leaves less water vestige and the other one leaves much more vestige (showed in the following picture).
Now we come to see some pictures I took in the open air.
Image without Benro PD CPL used
Image shot with Benro PD CPL screwed on
A method for contrast enhancement for digital images is to use polarizers. It is know us all that because of reflecting off electrons in air molecules and causing the light to scatter into what appears as haze, so the light from the sun becomes partially polarized. When shooting skies, with polarizers screwed on, we filter the polarized light out, decrease the light intensity and darken the skies to make the contrast of skies and cloud much clearer. Benro PD CPL did achieve the effect. When taking pictures, it demands to rotate the front filter elements while looking into the viewfinder. When it becomes the darkest in the viewfinder, the image contrast is the most obvious. The difference between the lightest and the darkest is 90 degrees and you can adjust the light contrast to be the degree according to actual image need.
Polarizers are used to reduce polarized light caused by the reflection of non-metallic surface (the reflective light by metal surface is not polarizing light and the polarizer doesn’t work on it) to make the picture be much sharper. In the above two pictures, the second wooden speaker is shot with filter screwed on lenses. We can see, the reflections are eliminated and the color and the texture are clearer.
Screenshot of pictures shot without and with Benro CPL(the red part)
When shooting in the open air, especially something in water, polarizers can reduce the reflections by water to reflect clearly such objects like fish and stone. Certainly, the condition is that the projection angle of light resource should be paralleled to the camera’s shooting angle and the largest polarizing angle should be between 30-40 degrees. After adjusting the angle well, rotate the front lens elements slowly to minimize the reflections by non-metallic surface. In order to test see the performance of the filter, I took the above picture at noon and the part in red frame will be enlarged to see the difference with and without filters screwed on lenses. The following two pictures are the screenshots. The top one is taken without polarizer and the blow one is taken with Benro 77mm PD CPL-HD WMC.
From the enlarged screenshots we can see that the picture by Benro PD CPL has more saturated color and is as clear as the original picture, even the dark part is showed clearly too. The reason is that the CPL eliminates the reflective light by leaves to decrease the light contrast of picture, so the original color of the leaves appears and even more saturated with the reflective light reduced (the blow one). On the contrary, at noon, the light is too bright and without the CPL, the camera will decrease exposure to protect the image detail when checking light automatically, which leads to the decrease of the detail of the dark part (the top one).
The above three pics are taken to show the changes of the exposure time after screwing the polarizer on. When using AP and Live View and Info and rotating Benro PD CPL to different angles, we can observe that the exposure time occurs some changes and the shutter speed decreases gradually too. When filtering out the polarized light, the polarizer also reduces the non-polarized light that has the same vibration direction with polarized light. That is to say, the amount of light that enters lens will be reduced and the exposure time will be increased after screwing the polarizer on. The first picture shows the LED EV (1/800, F2.8) which is gotten by rotating the front lens elements to different angle but without polarizer screwed on. It is not difficult to see the exposure time is very short. While after screwing the CPL on lens, even the polarizer filters out a little reflections, the EV is still 1/500 F2.8 (the middle pic) and the EV is 1/320 F2.8 when rotating the polarizer to eliminate most of the reflections (showed as the blow 2 picture), which is especially good for us to shoot at night.
Sky of Hulun Lake shot without Benro PD CPL
Sky shot with Benro PD CPL
Clear color contrast
Beautiful water and blue sky shot with Benro PD CPL
Benro’s filters in PD series are made from high-light transmission superior flat glass coated WMC water-proof coating. The rugged black aluminum alloy filter ring stands out lens only 3mm, avoiding the occurring of shadow even when screwed on wide lenses. Besides protecting the front lens elements, it does reduce the reflective polarized light effectively and increase the exposure time effectively, making the images more saturated and have clearer and sharper contrast. The excellent quality of Benro’s filters makes it the ideal choice of shutterbugs and professional photographers. I recommend it you sincerely.