Optical Quality of Cokin Filters

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I am in the process of acquiring some filters. So far, I have only purchased Hoya Super multi-coated glass filters, to maximise on the optical quality, minimise flare, and perhaps maximise contrast. However, I would also like to get some Cokin filters, and wondered if anyone has any information/views on the optical quality of these compared to the best of the glass filters.

-- Ed Hurst (BullMoo@hotmail.com), July 26, 2000

Answers

I guess no one else wants to comment on Cokin filters.

Cokin makes optical resin (plastic) filters and some glass filters as well. Most of them work with Cokin's adapters (A, P & a really big version too) for use with most sized lenses. Cokin also makes some regular screw-in filters, but I've never used any, so I can't comment.

There is no way that Cokin's plastic filters will compare with Hoya, or anybody else's Super multi-coated glass filters. For one thing, they have no anti-reflective coating. They are also quite prone to scratching. Their neutral grads produce a slight color cast too, not that it would be a concern to print film users though.

There are some snobish photographers that hate Cokins simply because they are made in France. There are also a lot of serious users who have simply gotten tired of replacing scratched filters on a regular basis. The truth is Cokin makes some very useful filters for very reasonable prices and they make a bunch or worthless crap (IMHO of course). If you can keep the light from shining on them so they don't produce a lot of flare, and you treat them very carefully, they can work well for a while. But they will get scratched eventually.

So, if you are a careful sort of person and only want to use them occasionally, they might be the best choice for you. As far as optical quality, I have never heard a valid claim from anyone that a Cokin filter made a picture less sharp, unless they were using one of the filters designed to do so. Or less contrasty, unless they had a flare problem, which any non-coated filter could do.

-- Jim Strutz (jimstrutz@juno.com), July 29, 2000.


Actually, Cokin filters are now made only with glass. Some of the galss is "natural" meaning amde in the tradition manner from sand, and ther est are "mineral" glass meaning synthetic compounds similar to natural glass. They aren't "plastic" though the gradients and tint may use plastic elements.

For an amateur or beginning photographer, Cokin filters are a great deal. You can get started using them at very little cost, then move up to a higher-quality, higher-priced system later. If you're buying Cokin for the first time, get the larger P-system. Other filter makers produce filters for that size. The smaller A-system fits smaller lenses, but no other filter maker manuafactures compatible filters. If you're unsure which to get, ask at your camera shop.

It also helps to keep in mind that Cokin, Hoya, B&W or any other brand filter is simply a piece of glass and you'll probably scratch, chip, or crack it at some point (even the most meticulous photographers have accidents!) so you can plan to get a higher-priced filter as a replacement ....

-- Dan Andrews (danger@mindless.com), April 20, 2001.


Actually Cokin filters are made from CR39 optical resin, which is a plastic. This information comes from the Cokin home page. Here is a web address with more information about CR39.

http://www.df.unibo.it/macro/intercast/charact.htm

-- Keith Goodwin (thunderam@yahoo.com), June 24, 2001.


I started out buying screw in filters and they got very expensive. When I started using cokin filters I noticed that they got scratched easily.But the easy way to fix this is to get some stick on felt dots and stick one on each side of the case to hold the filter centered.The other problem I noticed was the hoods didn't cover the rear of the holder.But you can take an extra hood by a local woodworking shop and ask them to sand half of it off to fit on the lens side of the first hood.It works good if you cant use your hand to cover it up.As far as quality-I haven't seen a picture of mine yet that the cokins or screwins had any different effect.The only cokin to be aware of is there grad. greys.They are not neutral,but rather do impose a grey tone.

-- jason durrance (bvjd@juno.com), December 04, 2001.

What colour is this imposed grey tone that isn't a neutral grey?

-- Robert Segal (robertsegal@juno.com), December 04, 2001.


Cokin has 3 solid nd filters that are neutral to colors.They also have 3 grad greys that aren't labled as neutral for a reason.They do reduce exposure by 1,2,and 3 stops,but the stronger you use, the more noticable the grey tone left behind.It is especially noticable in clouds, which tend to lose there white in favor of grey.

-- Jason Durrance (bvjd@juno.com), December 05, 2001.

So, these grad greys impart a "grey tone" that makes white things grey. But the neutral density filters turn them neutral instead of grey. I see.

Despite four years in art school, I have never seen the colour "neutral," so I don't know what it looks like. In the past, I may have mistaken it for grey. I stand corrected. I used to think the addition of pure grey would cause a change in value (bright/dark) unencumbered by a change in hue. I guess I was acting naively and from now on I'll be sure to always buy grad neutrals instead of grad greys. I'd much rather see neutral clouds than grey ones.

Now, if we wanted to enter a discussion of "warm grey" or "cool grey" or other, more specific colour shift to the Cokin grads, we might find ourselves on turf traversed many times in greenspun.com and Photo.net discussion threads: that many contributors have a problem with the neutrality of Cokin greys. These contributors feel the Cokins impart a colour cast, although very few will indicate which colour they are seeing. One who does is Patrick Matthiessen, who in http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=001KXi says:

"The biggest problem with the Cokin grads in my experience is not that they have a slight color cast, it is that the cast is not predictable. One filter may have a slight magenta cast while another may be slightly green. Once you know what your filter does and are happy with it, it's no big deal. We are talking about very slight changes here. Much greater changes in color happen when you change films, or the sun goes behind a cloud, or you change printing papers, etc. The Singh-Ray filters however, can be depended upon for absolute neutrality--for all that's worth. What film is absolutely neutral?. . . In photographs in which almost imperceptable color changes are tolerable, I trust the Cokin grads for a sharper transparency/negative."

Ellis Vener says, "they have a slight greenish cast to them." [ http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=000IZA ] and later in the same post adds "I have seen them be slightly blue/cyan or slightly greenish."

In the same thread Odd Ea, "also had a (definitely) greenish filter, which was exchanged by a Minolta/Cokin rep free of charge for a more neutral one."

And Meryl Arbing, in http://www.photo.net/bboard/q-and-a-fetch-msg? msg_id=0014vb , says (6 October 2000):

"Actually, Cokin has addressed the criticism that its Grey grads were not true ND and are now producing a grey grad that is really Neutral Density. Also, it is commonly stated that Cokin filters are made of fragile resin when, in actual fact, most are made of CR39 Organic Opthalmic glass and the rest are made of mineral glass. You may view the updated Cokin home pages at:

http://www.cokin.fr/icone6-p1.html

http://www.cokin.fr/icone5-p3.html "

- - - - - - -

Now, the whole matter of whether greyness equates to neutrality or not, and, if so, to what degree, is taken up in http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=0001nI , called "Graduated gray vs graduated ND?" in which the consensus seems to be filters are called grey if they vary a bit from true neutrality.

So, while filter companies seem to feel they can be sloppier if they call their products grey instead of neutral, a truly, dead-on, neutral grey is *still* grey and will still make white objects grey -- exactly as grey as a neutral filter will. They are identical. Neutrality is a specific subset of greyness. 'All that is neutral is grey but not all that is grey is neutral,' as it were.

This still leaves me with only one task with which to occupy my copious spare time: to find the colour grey on the colour wheel. I suppose I shall look for it somwhere between green and cyan.

-- Robert Segal (robertsegal@juno.com), December 06, 2001.


Thanks for the info.If I induced sarcasm I apologize.I am glad that you mentioned variations in film type.I shoot on Fuji Reala color print film because I don't wish to mess with slides.Every time I get a filter,I shoot a whole roll in different lighting conditions to see the effect.My comment on grey tones was due to looking at my photos of both the grey grad and nd solid in the same 2 stop strength.It is also something you have to look for.Noone has ever looked at my photos and asked why they had a slight grey tone.My comment was directed more to anyone who lookes long and hard at there photos time and time again wondering how it could have been better.

As for the filter system itself, its versatility in movement,positioning,and price is excellent and far outways any grey tone that you may or may not see on any given film, paper, or lighting condition.Everyone has to form their own opinion on a product based on their personal needs.If my comments offended anyone, you have my apologies.

-- jason durrance (bvjd@juno.com), December 06, 2001.


No apologies necessary. Forgive me, Jason, for going smart-assed when I get bored. Thanks for taking it well!

Ciao!

-- Robert Segal (robertsegal@juno.com), December 07, 2001.


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