How to clean your filter

[@TheNakism]

Do you do anything differently for mounted filters?

[@TheAntibozo]

It seems to me that wiping in a circular motion like that risks leaving small concentric scratches whose distortion will converge in the light path. Wouldn't it be better to wipe radially, one edge to the other?

[@sandb1867]

Then don't leave scratches, however you like to wipe. I think it's more important to remove as much debris as possible at the outset, as he mentions, and work in a clean environment. Furthermore, damaging the coatings is not likely to have any effect on the optical figure. I would think any light scratches might manifest as a tiny amount of unwanted light scatter.

[@TheAntibozo]

​@@sandb1867 It isn't a question of not leaving scratches; it's a question of minimizing the optical effect of any scratches that may occur. It's limiting risk.

[@sandb1867]

@@TheAntibozo I'm saying the risk of scratches is minimal (if the precautions are taken) and the risk of any effect of scratches to be smaller still.

[@TheAntibozo]

@@sandb1867 And i am saying that, in the event scratches occur, likely or unlikely*, selecting an appropriate direction of movement can reduce the optical effect. You are talking entirely past my point. * Of course scratches will occur. They may be microscopic, but without a doubt they will occur. What you are discussing is a matter of degree, yet you erroneously employ absolute terms.

[@sandb1867]

@@TheAntibozo Look at my first reply. Who's talking past whom. Scratches will not have the effect you describe and your method of wiping radially will not mitigate your imagined risk.

[@petergeanacopulos5327]

Does this work for EVERY type of manufacturers filters? I have just obtained second hand Baader OIII and Ha filters with a few minor finger prints on them and I wanted to clean them.

[@OSITelevision]

It might work, but I would consult with the manufacturer first. We don't know the coating quality of those filters. That said, this is still the best cleaning practice available.

[@matthewbrown8679]

Hi. I try it this way, and I can't not get streaking everywhere. I'm using 99% isopropanol and kimwipes. Any suggestions?

[@OSITelevision]

Hi Matthew, Certain filters, H-alphas for example, are more difficult to clean than others. We have a Lumicon cleaning kit available to help: farpointastro.com/products/lumicon-advanced-lens-cleaning-kit There is also a closeout version: farpointastro.com/products/lumicon-advanced-lens-cleaning-kit-old-style-closeout

[@stanburman9978]

This is a very helpful video. And I subscribes to farpointastro. But the video is not there. Can you add it please?

[@OSITelevision]

Hi Stan, thanks for subscribing! I'm not sure what you mean about the video not being there? It is uploaded, that's how this page is here

[@stanburman9978]

Thanks! I can see it now.