UV Filters

[GrahamS]

This will surprise many people: http://www.lenstip.com/113.1-article...ters_test.html

As far as I am aware, Cokin filters are all acrylic and are square effects filters, not for permanent fitment.

[arith]

Hoya Super HMC Pro 1 UV(0) or Hoya HD are the cheapest good ones I could find. My Hoya Super HMC Pro 1 UV(0) is chipped since a toff with a flash yellow sports car did a wheel spin in front of me throwing grit around at Trafalgar Sq, it is still good for use with only a little extra CA when pointed into sun, the HD I use on a lens that doesn't normally point at the sun.

http://www.hoyafilter.com/hoya/produ...rs/hdfilteruv/

[jcuknz]

Interesting you mention Cokin as that is a flexible 'add-on' sytem where you have a mounting which screws onto the lens and then you slide rectangular filters into the slots in the holder The holders come in A, P, and a larger size ... the genuine Cokin A also has a special slot behind the other slots for a polarising filter, THEIR filter which has a knurled edge sticking out from the holder so it can be rotated. There are numerous clones around which simply hold the square filters.
They also make a lenshood to fit in the front slot ... holders have two or three slots so you can combine different filters. Most useful IMO and essential if using graduated neuitral density filters.
But for protection you need the round screw-on filter or simply quality glass .... never been to your country but my impression is that you probably do need the protection from the dry dusty outback? I'm suprised AB26 has not joined this discussion as he is from your country and would be a good advisor.

EDIT ...I had a brilliant idea which didn't work some years back when I wanted a Infra-Red filter and the cheapest way was to buy a six inch square of the stuff [ from SRB-Griturn ] and cut it in four, on-selling three quarters to fellow photonuts. I then slipped this gel into my Cokin and got my IR results AOK ... the hitch was that the Cokin has a lot of holes around it and with the long IR exposure light entered through the holes and bounced around and spoilt the photo .... so I realised I needed to glue the further cut-down gel to an old unused filter I had, a pale blue colour correction filter ... since then I have got good IR results So that is an oddball drawback to using the Cokin system.
Further EDIT

This is the lash-up I made when all I had in digital was a Canon s20 P&S and I was shooting IR ... so gel in Cokin [clone] with lenshood up front and my viewfinder to help seeing image on LCD in sunlight on back ... no camera in photo as I need it to take the shot
Cokin holder and Grad ND

PPS ... You fit Cokin to your lens with a removable ring which comes in sizes to suit the lens thread so one holder can be used with several lenses. You probably would need the P or larger size for a DSLR with a large lens and if using a wide angle lens it probably wouldn't work at all.

[shoshanna]