STC Cine Mist CPL Filter

The filter in this review is a little different from the usual run of the mill filters you see around – it is a Cine Mist and Circular Polarising filter in one.

STC very kindly sent me this filter to review before it was officially anounced in the UK, hence I have been busy out and about using the filter under different conditions before writing this review.

What does a STC Cine Mist filter do?

To quote from STC direct – the filter delicately handles highlights, providing a natural and subtle softness without excessive effects. There is a gentle brightening in the shadow areas yet still maintaining contrast and producing naturally soft and clear images of cinematic quality without the overly sharp harsh effect that some high resolution digital devices produce.

As is standard for STC, the Cine Mist CPL filter is supplied in high quality square plastic case fitted with foam inserts, included is the STC lens cleaning cloth, UV test card plus a guarantee booklet that is signed by the technician who quality tested the filter. Like all STC filters the Cine Mist CPL filter is double sided anti smudge, anti-static and anti-reflection nano coating, it is also serial numbered to enable the user to register the one year guarantee. Worth noting is that all 3 STC filters use German made Schott B270 Crown glass.

To see how the STC Cine Mist CPL filter performs I tested it against 2 other STC CPL filters, – these being STC Hybrid CPL and STC Hybrid Pure CPL, plus a relatively unknown brand – this being a Zomei CPL. – The Zomei filter is multi coated and uses Japanese made AGC optical glass.

Test Equipment and Proceedure

For test purposes I have standardised by using a Nikon D800 equipped with Nikkor 24-85mm f3.5-4.5G ED  mounted on Manfrotto 190 tripod fitted with 115 head. All exposures made using a remote release cable and the camera eyepiece cover in place.

Camera settings were: Standard colour, Adobe RGB Colour Space, Daylight balance, Contrast Normal, 0 exposure adjustment, Aperture Priority, Matrix Metering. All images were saved as RAW files.

The first 2 frames of each focal length test were made without a filter, then 2 exposures were made with each filter in place.

The first test involved photographing a gray target in bright early afternoon sunlight with each filter in turn – the purpose of this test was to check for any significant colour shift any of the filters. The camera was set at 400 ISO using an aperture of f8 and the focal length was set at 85mm. Exposures were made in aperture priority mode.

 

Without filter

STC Hybrid CPL

STC Hybrid Pure CPL

STC Cine Mist CPL

Zomei CPL

For the second test the photographs were taken late morning in direct sunlight, this time the ISO was set at 100 and the aperture set at f11 with a focal length of 50mm. This time 2 frames were taken at minimum polarisation of the sky and 2 frames at maximum polarisation.

Filters set to Minimum

Without filter                                STC Hybrid CPL                       STC Hybrid Pure CPL                   STC Cine Mist CPL                                  Zomei CPL

Filters set to Maximum

Without filter                                STC Hybrid CPL                        STC Hybrid Pure CPL                      STC Cine Mist CPL                                  Zomei CPL

Using a colour balanced monitor all the images taken were viewed in Adobe Camera Raw where the image and histogram of each file were examined for signs of colour shift and then the RAW files for each exposure were viewed at 100% in Adobe Photoshop – an image without a filter used was the baseline upon which all the filters were judged. At the same time I examined the Cine Mist files for its advertised effects characteristics.

Conclusions

Examining all the images side by side for colour variations it can be seen that the STC Hybrid Pure CPL filter produces a clean slightly cool image whilst the three remaining filters display a slight yellow/green shift, this is highlighted when the filters are used at maximum polarisation with the Zomei filter showing a stronger shift than the STC Hybrid CPL and the STC Cine Mist CPL. In practice and in isolation the  colour shift is nowhere as obvious as the side to side comparisons.

The STC Hybrid CPL and STC Hybrid Pure reduce light transmission by half a stop, whilst the STC Cine Mist reduces light transmission by a full stop and the Zomei CPL reduced transmission by a stop and a quarter. Both STC Cine Mist and Zomei filters are full strength polarising filters whilst STC Hybrid and Hybrid Pure filters are 70% strength polarising filters. The 3 STC filters polarised light smoothly and evenly, the adjustment ring in all cases rotated smoothly with just the right amount of resistance, the Zomei filter made a good job of polarising – but the adjustment ring had a very obvious rough spots when rotated.  All the filters maintain good sharpness when compared against the control image, the STC Cine Mist CPL filter give a very gentle softening, but it takes a very close examination to see – I would call it a very slight rounding of the image rather than softening, (this filter is listed as being 1/4 strength diffusion) STC also indicate that shadows are slightly brightened – again a very subtle effect and born out by my own trial images. I certainly like the results this filter produces.

Since I take a lot of landscape photographs I have tended to have either a STC Hybrid or STC Hybrid Pure CPL filter on my lenses almost permanantly, I have a feeling that they may have to take second place being replaced with the STC Cine Mist CPL filter. I thoroughly recommend the STC Cine Mist filter.

Sample Images

STC Cine Mist CPL Polarising effect