• STC Pure Hybrid CPL Filter

    STC recently announced the release of a revision of their well known Hybrid CPL (Circular Polarising) Filter.

    What is the difference between the ‘New’ Pure CPL Hybrid filter and its predecessor? According to STC the new filter has a more neutral colour balance.

    I have used the original STC Hybrid CPL filter for some years now, so was interested to see the difference between the two filters for myself. As a result I obtained a STC Pure Hybrid CPL filter and put it to the test.

    What makes the STC Pure Hybrid CPL filter special?

    Made with Schott B270 super tough glass, has a double sided anti reflection, antistatic, oil and waterproof coating, the filter edge is black rimmed to reduce reflection from the edges of the filter, the filter rings are Teflon coated to ensure smooth rotation in addition to this a special polarising film is used . All in all this makes for an ultra light and ultra slim polarising filter which also cuts UV light.

    Being a Hybrid filter it cuts light transmission by only 1/2 a stop whilst giving a 70% polarising effect.

    The filter is supplied in a square hard plastic padded case, also included are a high quality lens cleaning cloth, a UV test card (to prove how much UV light the filter blocks) and a certificate of accreditation– STC filters are individually numbered, this identifies the filter when registering to activate the guarantee.

    How the filter was tested.

    For comparison purposes both the STC Hybrid CPL and STC Pure Hybrid CPL were fitted to a Nikkor 24-85mm f4.5 – f5.6 AFG lens on a Nikon D800 camera body. The combination was mounted on a tripod, using a remote shutter release. Exposures were made in Aperture Priority, using an aperture of f11, metering was set to Matrix, 100 ISO, Neutral saturation and Daylight balance, files were saved as NEF and converted to Jpeg for website use in Adobe Camera Raw without adjustment.

    The NEF files were examined at 100% in Photoshop on a colour calibrated monitor.

    Making the test images

    Exposures were made without filter and at full polarisation. The filter ring was rotated several times on both filters to ensure that the full polarisation effect was used..The Teflon coated filter rings made rotation smooth with just the right amount of resistance.

    When using full polarisation underexposing by 1/2 a stop sometimes helps compensate for the darker blue sky causing the camera to overexpose.

    All photographs were taken in full sun from between 11.00 and 4.00

    Test Images

                                                                                                                           Colour saturation

    Without filter                                                 Original Hybrid CPL filter                                       Pure Hybrid CPL filter


    Notice the difference in the RGB channels in the example screen shots below

                                                                                                                                  Without filter

    Original Hybrid CPL filter

    Pure Hybrid CPL filter

    Without filter                                           Original Hybrid CPL filter                                       Pure Hybrid CPL filter



    Without filter                                             Original Hybrid CPL filter                                       Pure Hybrid CPL filter


    Without polarisation                                                                                                      Polarised with Pure Hybrid CPL Filter


    Without polarisation                                                                                                      Polarised with Pure Hybrid CPL Filter


    Colour difference between filters

     Left –  Original Hybrid CPL filter colour balance                                                          Right – Pure Hybrid CPL filter colour balance



    As can be seen by the above screen shots the colour rendition between ‘Without filter and Pure Hybrid CPL filter’ are quite evenly matched and more neutral, whereas the original Hybrid CPL filter shows a slight cyan cast. Sharpness with or without  either of the two Hybrid CPL filters is unaffected, nor is there any  evidence of fringing thanks to the ultra slim high quality Schott glass and multi coating used. The Pure filter also makes a very good job of blocking UV light – see the examples below for further proof.


                                                                                                STC Ultra layer UV filter                 STC Pure Hybrid CPL filter


    STC Ultra layer UV filter                 STC Pure Hybrid CPL filter


    When viewed on screen photographs taken using the Pure Hybrid CPL filter are clearly neutral, combined with only a 1/2 a stop light loss, excellent polarisation properties and being ultra slim profile and light in weight, add to this the fact that the filter is excellent at blocking UV light – this new version of Hybrid CPL filter ticks all the boxes.

    I keep a STC Hybrid CPL filter on my camera lens most of the time, the minimal light loss is hardly worth bothering about, plus it has the advantage that I have instant access to a polarising filter should the need arise.

    This filter is a premium product so expect to pay around £138 for a 77mm Pure Hybrid CPL filter.

    Would I recommend the Pure Hybrid CPL Filter?

    Short answer -Yes!  The STC Pure Hybrid CPL filter will be my main filter from now on.

    Extra Sample Images

    STC Pure Hybrid CPL filter


    Combination of STC Pure Hybrid CPL filter and STC ND 1000 clip filter


    Thanks go to STC and their UK distributor InfinityX for supplying the new Pure Hybrid CPL filter for the purposes of this review.

    As an extra incentive to purchase a Pure Hybrid CPL filter (or any other STC filter) there is a special 10% discount to be had when you add the discount code: 2023tpfp10off at the checkout through the link below.


  • STC Infra Red Clip Filters

    The sun has now started to appear on a near daily basis now. That can mean only one thing!

    Time to break out the Infra Red filters!

    I should start by thanking our good friends William and Ashley at STC Optics for kindly providing the filters used in this review and  Protech Repairs for converting the Fuji X-E1 to a full spectrum pass filter.

    In this review I will be testing 4 STC clip filters – 3 Infra Red pass filters consisting of: 590nm, 720nm and 850nm, in addition to this I will be testing a 650nm UV/IR cut filter.

    The frames of  STC clip filters are made from black anodised 304 stainless steel which is virtually non magnetic, the glass itself is a mere 0.5mm thick and has a special nano coating to prevent dust from sticking to it.

    First the basics – Infra Red pass filters allow the transmission of infra red light at varying wave lengths – the higher the number the less visible light is allowed through. A UV/IR cut filter on the other hand cuts out both UV and Infra red wave lengths – in the case of the STC clip filter, it absorbs UV light from 650nm. When fitted to a full spectrum pass converted camera and set to daylight balance it effectively becomes a regular camera suitable for general photography once more. (I used this particular set up when on holiday this year to reduce the number of cameras carried.)

    How to use the clip filters with a Fuji mirrorless camera.

    When using infra red filters of any kind the camera must first be adapted for use with infra red filters – this usually involves having the hot filter (this blocks infra red light) removed and replaced with a full spectrum glass. Warning – do not attempt do do this yourself, if something goes wrong you could be left with a very expensive paperweight! Contact a reputable company to undertake the process. – See link at bottom for my personal recommendation.

    Installing the filter

    When using the clip filters for a Fuji mirrorless system for the first time, be aware that on the reverse side of the filter the two outer edges have a sticky layer, this is revealed by removing the clear cover layer.

    Remove the camera lens and place the filter into the throat of the camera, ensuring the lettering on the filter is facing outwards –  most of the STC clip filters will only fit one way up with the exception of the Fuji filter , this will fit upside down, but with lettering outward. Very gently press the outer edges of the filter to ensure the sticky layer make contact, replace the lens.


    Inserting clip filter                                                                                                          Clip filter in position


    Before taking a photograph a custom white balance must be made. This is done by first setting the camera to ‘Custom White Balance’, (the exact method of making a custom white balance vary with each camera model, consult your camera manual for further guidance.) Typically a 590nm balance is created using a white sheet of paper, for 720nm and upwards the white balance is done using green foliage as the neutral point.

    The setup

    For this review I used a full spectrum converted Fuji X-E1 plus a conventional Fuji X-T1 as a bench mark for daylight colour balance. Two lenses were used – the lake images were taken using a Meike 12mm f2.8 manual focus lens, the broken wall images were taken with a Andoer 35mm f1.8 manual focus lens. Custom white balances were made and set prior to taking the photographs, lenses were stopped down to f8, shutter speed set to Auto and sensitivity was 200 ISO. In both sets of tests the camera used was fitted to a tripod. All images were saved as Jpeg fine, large and 3:2 ratio. Focus confirmed prior to exposure. Lighting conditions were bright and sunny. It is worth remembering that Infra red light focuses at a different point to the visible spectrum, so ignore the fact that when focusing the point at which infinity is sharp will not align with the infinity mark on your camera.


    Test images

    The Lake photographs are shown in ACR (Adobe Camera Raw) to illustrate the wavelengths of light each filter passes.


    590nm pass filter

    720nm pass filter

    850nm pass filter

    Converted Camera set to Daylight balance – No filter

    UV/IR Cut Filter – Camera set to Daylight balance

    Unconverted Camera set to Daylight balance – No filter


    Wall and doorway

    590nm pass filter

    720nm pass filter

    850nm pass filter

    UV/IR Cut Filter – Camera set to Daylight balance

    Unconverted Camera set to Daylight balance – No filter


    Additional Sample Images

                                       850nm Pass filter – Image converted to Black and White                                                 850nm filter – No Adjustment


    UV/IR Cut filter in converted camera – Daylight Balance                                             UV/IR Cut filter in converted camera – Daylight Balance



    All the photographs were opened and examined at 100% in Adobe CC on a colour profiled monitor, no alterations were made, the images are just as they came from the camera. The images were observed to be sharp from edge to edge and free from distortion and fringing.

    The photographs taken with display more detail in the shadow areas compared with the full colour images, it is worth noting that there is a colour balance difference between the images taken with the UV/IR Cut filter and the unconverted camera, this could be down to the amount of UV/IR being blocked by the clip filter compared with a lens without a UV filter and also the variance between the sensor arrangement of the two cameras used, in saying that either of the colour images is perfectly acceptable when viewed on its own.

    The all important question is. Do the STC clip filters offer value for money? For a Fuji X series APS-C  prices range from £96.99 for a single STC clip filter infra red filter (including case) to £111.99 for the UV IR Cut filter.

    Whilst this might appear expensive at first glance, consider the cost of purchasing a filter for each lens you wished to use and in the case of ultra wide angle lenses that have a protruding front element fitting a filter is not possible.

    Taking all this into account, the STC clip filter range offer excellent quality and great value for money. I own a number of STC clip and screw-in filters and would not be without them.

    STC are unique in the range of clip filters that they offer, fitting cameras from Nikon Z series to Pentax APS-C and most cameras in between.


    Update : STC Optics are offering readers of this blog a special discount on all their filters. Use the link below and add the discount code: 2023tpfp10off at the checkout.
    Filters can be purchased direct from STC Optics

    For further information on Infra Red conversions contact Protech Repairs

  • Back to Basics

    Have you ever noticed on TV and films how often a photograph is portrayed as being taken with an incorrect lens – amazing close ups from an impossible distance with a standard lens? Or how about the well lit photograph taken in near zero light?  Or how about one of my pet gripes holding the camera completely wrong? (I often see the last one when out and about.)

    I cannot do much about the first two items, but I can give some advice on this post about the last one.

    Part one – Holding the camera correctly.

    Do not grip the camera by the sides with both hands, this makes the camera unstable. Instead, hold your camera with your right hand by the grip on the right side (most cameras have a molded grip) place your left hand under the lens and tuck your elbows in to your chest, this forms a triangle which makes the camera a lot more stable and less prone to camera shake.

                                                     Incorrect grip                                                                                                      Correct grip


    Part two – Focusing correctly.

    When focusing or zooming a lens do not hold the lens on the top of the focus or zoom ring – this again makes the camera unstable due to the possibility of applying downward pressure. As with the correct holding position make your adjustments from the underside of the lens, this again in forming a triangle makes for a more stable arrangement.

    Incorrect method of  focusing                                                                          Correct method of focusing


    Although the illustrations in this post show the use of a film camera, the same principles apply to digital SLR cameras. If you have a viewfinder use it, on a tripod the rear screen can be used. I have seen more than a few people using the rear screen whilst hand holding the camera, not an easy thing to do! ( It is not a mobile phone!) This can once again lead to camera shake. In camera / lens stabilisation can correct for camera shake, it is designed as an aid to producing sharp photographs. However, good technique is better than relying on technology to correct for bad practices.

    Gripe over! I hope this post offers some guidance.


  • A Tale of Two TLRs

    What follows is a test of two TLR (Twin Lens Reflex) cameras, but first a little background information.

    I already own 2 TLR’s. – When one started to have problems with the shutter mechanism I switched to my second camera and soon after it too was having shutter problems, knowing that it might be difficult to get either repaired due to parts no longer being available I started looking out for a replacement. I found a Chinese made Seagull WWSC for sale at a very reasonable price, so I purchased it. Then a couple of weeks later I was browsing a local junk shop when I spotted in the corner of a display cabinet another TLR make and model not clear, I asked to take a look, it turned out to be an early Yashica C. The camera was very reasonably priced and the shutter appeared to be working ok, so I purchased it. I did not feel it was fair to leave it laying forlorn in the cabinet any longer – that is my excuse and I am sticking to it!

    The obvious question is. What do you do when you have 2 new (to you) TLR cameras? The answer is to take them out for a side by side test!

    For the purpose of the test both cameras were loaded with Rollei RPX 400 black and white film, all exposures were measured using a Lunasix light meter, apertures were set identically on both cameras and shutter speeds set accordingly. Both cameras were tripod mounted to eliminate the chance of camera shake and to enable identical photographs to be taken.


                                                         Seagull WWSC                                                                                                         Yashica C

    Year of manufacture            Approx 1996                                                                                                              1956

    Film format                              120 roll film                                                                                                              120 roll film

    Number of exposures         12 – 6×6 frames                                                                                                         12 – 6×6 frames

    Film advance                          Lever wind                                                                                                                  Wind wheel with safety button

    Viewing lens                          Haiou 75mm f2.8 – 3 elements in 3 groups                                                          Yashikor 80mm f3.5  – 3 elements in 3 groups

    Taking lens                            Haiou 75mm f3.5 –  3 elements in 3 groups                                                          Yashikor 80mm f3.5  – 3 elements in 3 groups

    Focus range                          1 metre to infinity                                                                                                       1 metre to infinity

    Shutter                                Between lens leaf shutter – B, 1 to 1/300th second                                                 Between lens leaf shutter – B, 1 to 1/300th second

    Shutter  actuation           Auto cocked via film advance                                                                                     Shutter cocked via separate lever

    Focus                                 Flip up hood with magnifier, ground glass screen with fresnel split                    Flip up hood with magnifier and ground glass screen

    Focus mechanism           Front standard focus via wheel                                                                                   Front standard focus via wheel

    Flash Synch                      At all shutter speeds/X +M / PC socket                                                                       At all shutter speeds/X +M / PC socket


    Loading the cameras

    The Seagull and Yashica cameras are both loaded the same way – that is that the unexposed film is placed in the lower chamber, the leader is fed onto an empty film spool in the upper chamber, the film is then advanced until the start indicator on the film lines up with the two dots on the back of the camera (see photo). The film back is now closed and locked with the wheel on the base of the camera and now the film is advanced via the wind crank in the case of the Seagull and the wheel in the case of the Yashica C. Reversing the Seagull’s crank lever cocks the camera shutter, the Yashica C shutter is set with a small lever around the lens – with the Yashica it is essential to set the shutter speed prior to cocking the shutter.

    Film start markers

    The cameras in use

    Both cameras a similar in operation – they have a pop up hoods with spring loaded magnifier to aid focus, the magnifier is utilised by pressing the centre of the hood, the magnifier then unlatches and flips up so it is above the focussing screen, once you have done with it just press it back into the hood where it will lock back into place. The Seagull has its focus wheel on the left side of the body, whilst the Yashica focus wheel is located on the right hand side. Aperture settings are adjusted via a lever and in both cases the range goes from f3.5 through to f22. Shutter speeds are likewise changed with a lever on the opposite side to the aperture scale, whilst the Seagull shutter speeds are from B, 1 ½, ¼, 1/8, 1/16, 1/30, 1/30, 1/60, 1/125 and 1/300, the Yashica having an older generation Copal shutter its speeds range from B, 1, ½, 1/5, 1/10, 1/25, 1/50, 1/100 and 1/300. Since most negative film has a degree of latitude the variation between the cameras is not an issue, it may however cause a problem with less tolerant transparency film.

    For those wishing to use a lens hood or filter, it is worth noting that the Seagull has a screw thread mount of 34mm, whilst the Yashica uses a more common mount found most other TLRs that being a Bayonet 1 mount.

    I noticed that focusing with the Seagull is a little easier due to the split prism centre spot in the focusing screen, but at the same time that the focus wheel

    The Results

    Since both the Seagull and Yashica have a similar optical setup, admittedly with a 5mm difference between focal length, the results were quite close. Neither lens was super sharp at full aperture, usable but only just, major improvements were seen by f8 and gained a little more sharpness by f11, nothing more was gained by stopping down to f22. Vignetting was well controlled on both lenses, not causing serious issues at any aperture. The only major difference between the two cameras was that the lens on the Seagull showed  slightly better control of flare, this is due to the fact that the Haiou lens is multi coated rather than the single coating on the Yashicor lens.

    Seagull WWSC                                                                                        Yashica C

    Seagull WWSC                                                                                                      Yashica C


    Either camera will give acceptable results, the lenses are not ‘state of the art’ sharp enough to provide a 30cm square print without too much trouble.

    The Seagull WWSC is suspected by many to have been built on old Japanese TLR tooling, the shutter has more than a passing resemblance to an early Copal shutter. Added to this the build quality is good but not stunning The WWSC is said to be the export quality of the Seagull 4a model. Putting a precise age on the WWSC is difficult due to the myriad of Seagull models released with little information on production dates.

    My Yashica C has definitely seen better days, but in saying that it is still a well built robust camera.

    Which camera would I recommend? Simple answer if you can find either one in good working order then both will give good results, just remember treat them carefully, set the shutter speed before cocking the shutter on the Yashica C and all will be ok

  • Agent Shadow – First Impression

    Whilst at the Photography Show in Birmingham last September I had the opportunity to meet with Stephen Dowling, the man behind Kosmo Foto and the promoter of two black and white negative films – Kosmo Foto Mono, rated at 100 ISO – available as 35mm and 120 roll film and the recently released Kosmo Foto Agent Shadow 400 ISO film, available as 35mm film which is being reviewed here.

    Neither film stock is a new emulsion, Mono is made by a European manufacturer (Foma) and Agent Shadow by a respected manufacturer with over 100 years experience. More about that later.

    There are those who would say that a rebadged film is a waste of time, but look at it this way – Ford does not make every component for their vehicles, a large number of parts are bought in from specialist manufacturers and nobody complains!

    On to the testing of Agent Shadow. I exposed one roll at the box speed of 400 ISO and a second roll at 3200 ISO. Agent Shadow is advertised as having the capability of being pushed to 6400 ISO. Both films were processed in 510 Pyro developer using the appropriate development times. Agent Shadow is marketed a being an emulsion harking back to the Film Noir Era, low light levels, lots of contrast and deep shadows. Both the rolls I exposed were taken under fairly flat lighting conditions, so contrast would be a bonus.

    For the purpose of the test I used a Nikon FM with either a Tokina 35-105mm f3.5-4.5 or a Nikkor 28 – 70 f2.8 lens. Exposure was set using a Gossen Lunasix lightmeter.

    How did the film perform?

    Having scanned both films at base settings I examined the results at 100% magnification in Photoshop. Both films displayed good contrast, a bit higher with the 3200 rated film – but this was to be expected and grain more evident but never obtrusive. Both films showed good levels of sharpness, combined with excellent shadow and highlight detail. Put plainly this film will work well under most conditions subject to correct development. If the film is processed in something like Rodinal, then expect more grain and a bit more contrast, but that is the nature of Rodinal and that is a matter of individual taste.


    The above photographs were exposed at box speed of 400 ISO

    The above photographs were exposed at 3200 ISO and processed accordingly

    How does Agent Shadow rate against comparable films?

    In practical terms, Agent Shadow has a slightly coarser grain structure than Ilford HP5 and Kodak Tmax 400.

    Agent Shadow is described as ‘similar to Ilford HP5 but a little less silver content’. This is also the description given to Kentmere Pan 400 ( a clue to its heritage?)  The processing times are identical another clue? Similarly Agfa APX 400 and Rollei RPX 400 also share the same processing times and are also both marked as produced in the UK, likely to indicate that they are the same emulsion all produced by Harman (Ilford). However since everyone has a personal favourite brand this is hardly an issue.

    If you are looking for a good all round film that will push process well, look no further than Agent Shadow.