Cleaning filters and lenses....am I being obsessive

M

Mdombros

Member
I recently received a couple B+W UV's and a new 77mm B+W Kaesemann CPol from Amazon. I spent almost an hour cleaning the Kaesemann. It had some smudges around the edge out of the box and no matter what I tried I kept seeing this light haze or smutz on the glass. Similar but not so dramatic problem with the UV's. I finally got it to the point where it was ok to the naked eye under a lamp and left it. Am I obsessing?

The glass looks real good under an incandescent bulb held to reflect. But I then examine it with an LED flashlight at an angle which brings out every imperfection. I swear I even see miniscule bubbles in the glass sometimes on the UVs. But always this "haze"....rub marks from where I pushed the paper around.

So, what am I doing to clean you ask.

I start with a good blow from my rocket and brush from a Giotto lens brush. Then I try dry Tiffen lens paper. At this point I see some, apparently, oily smudges and pull out the Zeiss lens cleaning fluid. I spray a hint of the fluid on clean lens paper and clean the glass. This leaves a light haze which I then obsess over with piece after piece of dry lens paper. Giving up on that I try my microfiber cloth which seems to do a better job on the haze but I prefer a disposable option like the paper. Ultimately there seems to be some haze constantly being pushed around that I can "polish" almost clear with the microfiber but not remove.

I thought it was perhaps the coating, perhaps softened by the Zeiss cleaner but the MRC coating on the B+W lenses is supposed to be harder than glass so I doubt that is it.

Are they just filthy from the factory? Am I trying for too much optical perfection?

Help and comments very much appreciated. And forgive me if this is the wrong place for this post, but it looked like perhaps the right place.


Thanks,
Matt
 
I share the same tendency, to the point I find it difficult to own touchscreen anything because I can't stand fingerprints. I never buy products with a gloss finish for the same reason. Even on my cheap bass guitar with black gloss finish it drives me crazy. But yes you are being obsessive. It is a nice feeling when your lenses are spotless though.

There may be a quality control issue there but blemishes on or in front of the lens ultimately have surprisingly little effect on the image. Small chips, scratches and dirt even fungus have to be real bad before it becomes significantly noticeable in the final image. Blemishes on the back end of the lens are a bigger issue but still lower impact than you'd expect. It is still best practice to treat them with kid gloves but in reality when you're trying to get the shot and everything is going wrong it's rarely practical. I used to baby my equipment a lot more and it's relatively easy to do in the studio but without a team of helpers it's a losing battle in the field. It doesn't mean don't try to keep them clean but don't let it stress you out too much. And be aware that overcleaning will eventually damage the finishes too.

There's a camera test out there which I'm sure someone else still has the link to where a guy progressively destroys a lens, in the final shots the entire front element is cracked all the way through across the middle and it barely effects the image. In the same vein I have a 200mm lens that has fungus so bad that I can't see a thing through it with the naked eye. Yet on the camera it produces an image essentially the same as a mild diffusion or soft filter. It's actually quite a flattering effect on people - removes wrinkles, reduces contrast.

I think the lens test I mention above was a tele as well so wider lenses may be more susceptible but the test was pretty extreme and the point is that optics can be pretty forgiving. If you look at the range of filters available you will see some that have a physical net across them, look close at a frost filter or a pro mist and they look real dirty. Old camera tricks involved putting vaseline on the lens, stretching stockings over the rear lens etc.
 
I try not to obsess too much over these things. This helped. Grease marks can be quite worse than scratches, though.
 
I clean when dirty, and even then very, very gently. It's a fine line between removing crud and removing the surface. In fact, cleaning the glass is the only thing I really hate doing - especially on wide angles with their ability to almost focus on the glass element. I've one wide angle that I can't use any longer because I marked the glass when cleaning off a sticky mark!
 
Yeah, no idea how they managed to do that to the lens, considering this. (sorry if I'm pushing the thread into the "lens gore" category...)
 
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