Various filters used in photography

1. Various Filters in Photography

2. UV Filter

3. • UV filters are used to block
invisible ultraviolet light, to which most
photographic sensors are slightly sensitive
• UV filters are primarily used to protect the
front element of a camera lens from damage
and dirt.
• UV filters reduce haze and improve contrast
by minimizing the amount of UV light that
reaches the sensors.

4. Polarising Filter

5. . Polarisers sort light into a single plane which
helps to darken blue skies, increases colour
saturation and reduces reflections in non-
metallic objects.
. The effect created by a polarising filter is one
of the only effects that can’t be replicated in
post production so it’s important that you
own one.

6. Areas where Polarising filters have the biggest
impact

7. Water
• It reduces the glare,water reflection and water colour

8. Sky
The color of sky can change remarkably using a polarising filter. Rotating
the filter you’ll see a blue sky change from a light pale blue color to a
vibrant and deep blue color

9. Colour
It cut down the reflection, this makes the colors of
some of these objects more vibrant.

10. • There are 2 types of polarising filters
Linear and Circular (CPL)
• Linear are traditionally used in film photography
• Circular is used in digital as they are designed to
not confuse the camera’s autofocus.
When you attach the circular filter to the end of
your lens you will find that you can still rotate the
filter, which changes the direction that the light is
polarised

12. Infrared Filter

13. Infrared or “IR” spectrum is not visible to the human eye but in
some circumstances it’s possible to capture it with your camera.

14. • Most digital cameras have an infrared blocker that is great for
regular photography but obviously not for infrared work.

15. Ways to do an Infrared Photography
1) Use a camera that includes a “night vision” mode. These cameras
generally include an infrared light

16. 2) Modify your camera to natively shoot infrared

17. 3)Use an Infrared Filter. Which is the easiest way.

18. ND Filters

19. Whats is ND filter
• A Neutral Density filter or ND filter is a filter that reduces or
modifies the intensity of all wavelenghts or colors of light
equally.
• They are called Neutral Density because the filter reduces all
light wavelengths reaching your cameras sensor without
affecting the colour reproduction
• It allows the photographer to select combinations
of aperture, exposure time and sensor sensitivity which would
otherwise produce overexposed pictures
• This is done to achieve effects such as a shallower depth of
field or motion blur of a subject

20. Situations where ND filters are particularly
useful include:
• Smoothing water movement in waterfalls, rivers, oceans, etc.
• Achieving a shallower depth of field in very bright light
• Reducing diffraction (which reduces sharpness) by enabling a
larger aperture
• Making moving objects less apparent or not visible (such as
people or cars)
• Introducing blur to convey motion with moving subjects

21. ND filters are quantified by their optical density or
equivalently their f-stop reduction
Optical Density F stop Reduction ND No. Notation % Transmittence
0.3 1 ND2 50%
0.6 2 ND4 25%
0.9 3 ND8 12.6%
1.2 4 ND16 6.25%
1.5 5 ND32 3.12%
1.8 6 ND64 1.56%
2.1 7 ND128 0.78%
2.4 8 ND256 0.39%
2.7 9 ND400 0.25%
3.0 10 ND1000 0.1%

22. To explain by example , I have a 9stop ND filter. I set up the camera in manual
mode and settings were ISO 100, f/9 and a shutter speed of 1/100s without
an ND filter and its showing a good exposure

23. Now when I placed the 9stop ND filter on the lens, cameras built in light meter was
showing a 9 stop (9EV) underexposure for the same scene. So to ensure to ge the
same exposure without the ND filter I needed to modify the lens aperture and the
shutter speed.

25. Use of ND filter for smoothing of water
f/9,1/80 sec, ISO 100 f/11, 50 sec, ISO100

26. Use of ND filter for motion blur
f/4, 1/1000 ISO 100 f/25, 10 sec, ISO 100

27. • One disadvantage of using an ND filter is that it darkens what
you see through the viewfinder rather dramatically and
depending on what type of filter you are using (16x, 32x etc)
your camera may not be able to focus at all because it is so
dark

28. Screw In System
• Hoya, B+W, Tiffen use Screw in filter systems

29. Filter Holder System
• Lee and Cokin use this system

30. Graduated ND Filter (GND)
• GNDs have variable light transmission. Typically half of the
filter is of neutral density and the other half is clear.
• It is used to bring an overly-bright part of a scene into
the dynamic range of sensor.

31. The GND filter comes in two categories:
Hard edge & Soft edge

32. Variable neutral density filter
• These work by placing two polarising filters together at least one of which
can rotate. The rear polarizing filter cuts out light in one plane
• As the front element is rotated, it cuts out an increasing amount of the
remaining light
• The advantages to this are that you get multiple ND filters in one package
• The disadvantage is a loss of image quality caused by both using two
elements together

33. Some of my work with a 9 stop ND Filter

43. Thank You!