In digital world, nearly every filter can be replaced by digital editing, but there are several must have filter that cannot be replaced by digital editing and it is important for us, especially landscaper and travel photographer.
Circular Polariser
This is a must have filter for landscape photographer, it cuts down reflection on water/ glasses, and make the sky more blue with popping clouds which is very nice effect that you cannot get by editing your picture in PS.There is 2 type of polariser: linear polariser and circular polariser.
Don’t choose the linear type, because it will fool your camera lightmeter and cause faulty reading.
Always buy the best CPL you could afford, because cheap CPL performance is not too good…you might end up with uneven dark sky, harsh transition and less saturated result.
Several recommended CPL manufacturers are
B+W (http://www.schneideroptics.com/ecommerce/CatalogSubCategoryDisplay.aspx?CID=57)
Tiffen (http://www.tiffen.com/tiffen_filters.html)
Heliopan (http://www.heliopan.de/Heliopan-Filters.pdf)
and camera’s OEM CPL
Personally i use B+W kaesemann MRC filter, which has the kaesemann polarising foil…one of the best polirising filter you could get in the market, coated with nice MRC coating so it’s more resistant to scratch.
There is hoax that spread around photographer is that thick filter will cause vignette...My B+W polariser is normal one (not slim) and I never found vignette because of the filter (even @12mm tokina)...it is true that little bit of filter ring will appear in your picture, but i don't think the slim model will eliminate this.
Be aware that there is also warm polariser available in the market...be sure which one you want to buy...if you're not sure, just try it...and buy which one you like.
For me, i prefer the neutral one...I could add the warm tone later by modifying the white balance.
Here is nice effect produced from using circular polariser filter:
Look at the blue sky, we cannot get the fluffy white cloud without circular polariser filter
shooting through the aquarium glass without reflection would be impossible without CPLGraduated ND
This filter is useful to minimise contrast difference between bright and dark area.For example when you shoot sunset/ sunrise, you often end up with underexposed/ over exposed area due to high contrast difference and limitation of camera’s dynamic range.
With this lens you could get nice balance that could be recorded by camera’s dynamic range.
Don’t buy the circular screw in type, since its not flexible when you need to adjust the transition between dark and bright area…as you know, we rarely shoot landscape with horizon in the middle. And with circular type you cannot adjust its position.
Buy the P series type which available from several manufacturer: Hi-Tech, Lee, or Singh Ray
Here’s the example of Gradual ND usage to shoot sunset.

Imagine without Gardual ND, I will never get the bright and sharp stone for attractive foreground shot because the sky will be very bright and overexposed.
I heard Cokin create also Gradual ND filter, but they are not neutral...it cause your picture little bit grey, which i don't like very much.
Just choose how many stop you want to reduce the exposure: 1 stop, 2 stop or 4 stop.
Neutral Density filter
There are several occasion when you want to slow down the shutter speed to get the effect you want, but you cannot push it further because the aperture is already at its maximum. Then you need this ND filter to darken you object. By make your subject darker, you could make the shutter speed slower, and produce nice effect to your photo.
You could choose from 2 stop, 4 stop or even 8 stop reduction. Singh ray produce vari-ND filter so you adjust the stop reduction according your requirement, but the price is quite crazy.
There are many manufacturers which produce this filter:
o Cokin (P series)
o Hi-tech
o Lee
o Singh Ray
o Hoya
o Heliopan
o Tiffen etc.
Some cheap ND will result in unnatural image result with grey/ reddish cast, and I would not recommend it.
Here is one slow effect picture resulted by this nice filter.
So guys...Is there any other filter required? Hmmm…as far as I know, other filter effect now can be simulated in PS which is more easy and therefore you don’t have to bring bags of filter with you during hunting…especially color correction...absolutely no..no:)
So...happy hunting guys























