Can cleaning a CP filter damage it?

[OviV]

I purchased a CP filter yesterday. I took one picture with it and the 100-400 L and it came out great. Today I cleaned it with Zeis Pre-Moistened Lens Cloth and not my pictures look like this:

http://www.shareapicture.com/vsalbum/getpic.aspx?fld=\OviV\Misc&pic=RV__MG_0965.jpg&OV=0

This is with two different lenses and at shutter speeds upto 1/1000 so it is not motion blur. You can actually see it through the view finder.

The reason I ask about cleaning is because this is the only thing I did between yesterday and today.

Ovi

[Jim_T]

All I can think of is that you got some fluid between the plates.. (That would mess things up).

Can you see any marks on the plates.. Have you held the filter up to the light to see if there is any fluid trapped between ?

[OviV]

O.K. Here's an update:

After seeing Jim's post I went to do a thoughrough examination of the filter and found no fluid whatsoever. I then decided to test it at different focal lengths on the 100-400. Anything above 200 MM at it starts to cause the blurring effect. This is the reason I did not notice yesterday since the one shot I took with it on was at 100 MM. So what now? Is this normal?

Ovi

[cmM]

i guess you could damage the coating on the glass if you scrub real hard.... but that's baad.

[cc10d]

I assume you have no problem without the filter? If so I would try to return or exchange the filter.

[12345Michael54321]

By any chance are you talking about the Zeiss pre-moistened lens cloths, in the blue and white box with "The ultimate convenience in lens cleaning for he ultimate lens and coating technology," on it?

If so, they're bad news.

Yes, I know they claim to be idea for cleaning things like filters, but I bought a box (of 50), for cleaning my eyeglass lenses. They seem to work well, but a little while later a distinct film is clearly visible on the glass.

I know, I know - it says "Zeiss," so we assume it's good. Well, I guess there's Zeiss, and there's Zeiss.

Oh, fwiw, the film can be readily wiped off with a moistened Kleenex. Or, in the case of optical glass filters, lens tissue.

[Bruce Watson]

Try a product called ROR, stands for Residual Oil Remover.

It will take off any weird films left behind by other lens cleaners.

Most camera stores should carry it. I get it from Henry's in Canada.

[ron chappel]

It's unlikely there is THAT much stuff left after using a slightly dodgey cleaning method.It could be but 'worse at longer focal lengths' thing sounds like it's another problem.
Circular polarizing filters are not easy to make really well,and this will show up at longer focal lengths.
I only found this out several months ago and it surprised me too.I was trying a cheap'ish brand cir-pol on a 400mm lens and was stunned how bad it was!Totally unusable even for a snapshot!! Just like you i could easily see it happening in the viewfinder
I asked around abit and found all this out.

Used on several shorter lens it was much better (and usable) but still less sharp than when using the lens without the filter

The end result of it all is that you really need to go with good brands of circular polarizers if using it on a long lens.Even then i'd be abit wary and maybe buy from a store with a good exchange policy

[BearSummer]

O.K. Here's an update:

After seeing Jim's post I went to do a thoughrough examination of the filter and found no fluid whatsoever. I then decided to test it at different focal lengths on the 100-400. Anything above 200 MM at it starts to cause the blurring effect. This is the reason I did not notice yesterday since the one shot I took with it on was at 100 MM. So what now? Is this normal?

Ovi

Hi Ovi,

wow, sucks to be you at the moment, on the upside you do have a 100-400 :). After looking at your pic, it actually looks like its camera shake. All of the blurring seems to match and be in the same direction. Are you sure it was shot at 1/1000, is that what it says in the exif info for the shot? My guess would be shot at 1/100 at 400mm without IS.

I would suggest that you try shooting the same object with and without the filter. Set the camera to TV and 1/400, turn IS on if you want to. If it only appears with the filter on then its shagged, try the ROR as suggested. Also hold the filter so that it reflects a bright light and see if the surface is scratched. If it doesnt appear then it could be that you have enabled safety shift in your custom functions and its wound the shutter speed down to give you a correct exposure.

And to answer your question, no it is not normal to do this.

Hope the above helps

Best regards

BearSummer

[OviV]

It is definitely not camera shake. That image was not at 1/1000 but I took others that were and exhibited the same problem. That particular image was taken by my wife on a tripod at 250MM and at 1/250 speed. We took the CP off and took another exact image and it came out tack sharp. Like I said, it is visible through the viewfinder even. I am going to take it back and get something else. This was a relatively inexpensive one ($70 if you can call that inexpensive but I know that CPs are expensive)

Ovi

[OviV]

Michael,

Those are the ones that I am using but I have never seen the symptoms that you describe. They always leave a clean streak free lens for me and they did so in this case as well.