Newsgroups: rec.photo
From: acs@csri.toronto.edu (Alvin Chia-Hua Shih)
Subject: Re: Cokin filters - any good?
Date: 21 Jan 93 22:20:36 GMT

Here is the summary from not very long ago:

From: thos@suite.sw.oz.au (Thomas Cohen)
Subject: filter summary (possible repost, as the other one may have missed)
Organization: Softway Pty Ltd
Date:  3 Dec 92 03:24:41 GMT

Okay, here is the summary of the replies to the filter query I posted
a few days ago...

The questions were basically :

1) cost
2) longevity
3) optical performance
4> different lens sizes
5) handiness


1. Cost
On the cost side of things the consensus was that individually they
are cheaper (although in Australia not by much). Unfortunately also
most people said that the Cokin range was largely gimmicky, and there
were a number of people who only used the ND or the Grad filters.

One chap (who also sold them) said that he received had good results 
from them, including the close up filter.

Also noted was the fact that the basic colour filters were quite cheap,
but that Kodak Gels were also a very good way of producing colour 
alterations.


2. Longevity
This was a livelier discussion - everyone said that it was easy to 
scratch a Cokin filter, most people also said that unless you had
lots of scratches it wouldn't make any difference. It was possible 
however to ruin a Cokin filter, but other people made the point
that it was as easy to ruin a screw-in filter.

Cokins also attract dust. One person also said that when you clean
the dust from one side it seems to blow around the filter and attach
to the other side!

Buying the filter case was seen as a plus, except that it wouldn't
fit the P series filters (for info on the difference between the A
and P series, see below). 


3 Optical performance.
Most people who used them were happy with them...but there were a 
few comments along the lines of 'unless it's critical' and 'try it
with Cokins, then buy Tiffen'.

Also the 'gimmicky' nature of most of the Cokin range was discussed
further. Most people said that the grads and NDs were the only ones
they used, and that they were very happy with the results of those.
Other comments were that they'd tried several grad filters and were 
happy with none of them. Concern was expressed that the closest that
Cokin did to a ND grad was the grey grad, which did leave a colour
cast.

Some people expressed doubts as to the polariser's ability, and a 
few said they used glass polarizers only. Others had used the polarizer
from Cokin and were happy with it. _Caveat Emptor_ I suppose.
The fact that Cokin make a linear and a circular polariser was seen 
as good (cirular polarisers are generally unnecessary, unless you
have a particular metering/focussing pattern).


4 Different lens sizes

Here is the reason for buying Cokins - almost. There are two series of
Cokin filters available. The A series will fit lenses up to 62mm, and
the P series will fit lenses up to 82 or so. What you get is an adapter
which screws into the lens, like an ordinary filter, and then a mount
clips onto that. Because the adapter is round the mount can be tilted
to any angle relative to the camera body. There are adapters which allow
the P series mount to fit to any lens size, so a P series is the one to
get if you have (or expect to get) any large lenses.

However, buying all this hardware is not that cheap. (It isn't expensive
though). Most people said that if you already had a large lens with 
filters, it would be far cheaper to get a step-down filter ring, which
would allow filters to fit both lenses. An advantage of this is that if
the smaller lens is a wide angle, fitting larger filters mean that you 
can use more before vignetting occurs.


And a final comment on awkwardness :

Cokin filters were held to be rather more awkward than normal screw-in
filters. They needed to be handled more carefully, and they were a little
more bulky. On the other hand, if you want to bracket with and without
filters, it seems it would be much quicker to change the filtering with
a Cokin setup than with a screw-in setup.

It was noted that the hood was probably unnecessary until it was! if you 
know what I mean. (ie. don't buy it on the assumption you'll use it a 
lot - you may never need it).


-------
And finally, thanks must go to...
dp@world.std.com (Jeff DelPapa)
rdb1@homxb.att.com (Ronald J Deblock, Jr)
m18709@mwvm.mitre.org (Andrew R. Lacher), who forwarded
replies he received from :
    mtoms@ems.cdc.com (Mark Toms)
    tanguyen@ucdavis.edu ( )
    gordon@meiko.co.uk (Gordon Henderson)
    pojee@ccwf.cc.utexas.edu
    nataraja@rtsg.mot.com

thanks guys!
----

regards,
-- 
thos cohen                                     |Softway Pty Ltd
                                               |ACSnet:         thos@softway.oz
 "Lex is a flaky implementation of a bad idea" |UUCP: ...!uunet!softway.oz!thos
                          - Ken Thompson, 1988 |Internet:    thos@softway.oz.au

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