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Paz    656
On 11/11/2017 at 11:10, Ricochet said:

I prefer a variable polariser on the moon, not so much to "protect" my eyes but to tweak the brightness to maximise the contrast. However, this is with a 2" polarising filter in my 2"-1.25" adaptor and a 1.25" filter on the eyepiece, so that rotating the eyepiece in the focuser allows the brightness to be easily adjusted. With a 1.25" Newtonian focuser you can only do this if viewing the moon through a barlowed eyepiece where one part of the filter can be screwed to the eyepiece and the other to the barlow. Fixing both parts to the eyepiece will require adjusting the brightness with the filter out of the focuser.

A Neodymium and/or yellow (or even red if lunar viewing isn't the last thing on your agenda) wrattan filter can also help improve lunar contrast at the expense of altering the colour.

That's a great idea! I've got a polarising filter that I no longer use due to not wanting to be fiddling around in the field, but I could split it, put one bit in the end of my diagonal and one on my eyepiece and then just tweak the eyepiece. Still some fiddling but much better than taking the eyepiece out every time you want to adjust.

With regard to the original post if you have a lense cap on your telescope with a smaller cap in the centre that you can take out that will give you a smaller aperture which will give you dimmer (and cleaner) views at lower magnifications.

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John    17,533
29 minutes ago, Paz said:

...With regard to the original post if you have a lense cap on your telescope with a smaller cap in the centre that you can take out that will give you a smaller aperture which will give you dimmer (and cleaner) views at lower magnifications.

This certainly will work to dim the image but the OP's scopes are 100mm and 60mm respectively. Not large apertures to start with so I'm not sure that reducing them further, with the consequential reduction in resolution and contrast, is a great idea :icon_scratch:

 

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Paz    656
3 hours ago, John said:

This certainly will work to dim the image but the OP's scopes are 100mm and 60mm respectively. Not large apertures to start with so I'm not sure that reducing them further, with the consequential reduction in resolution and contrast, is a great idea :icon_scratch:

 

That is fair comment but if the option is there to try stopping down its worth doing if only to see for oneself the effects. I do this with my st120 and st80 at lower magnifications on the moon and enjoy the views.

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John    17,533
1 hour ago, Paz said:

That is fair comment but if the option is there to try stopping down its worth doing if only to see for oneself the effects. I do this with my st120 and st80 at lower magnifications on the moon and enjoy the views.

Agreed. It is another option :smiley:

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Philip R    665
On ‎11‎/‎11‎/‎2017 at 11:35, Stu said:

That is very true. One possible option, which relies on having enough back focus is to put a short 1.25" extension in which you screw one half of the polariser to, that way you can still add the second part to the eyepiece and rotate it to get maximum brightness.

post-4682-0-11788500-1428586852.jpg<--- i.e. something like this.

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Charic    2,011

I bought a cheap  metal framed glass Moon filter, probably used it once, but its there if I need it!

I have also tried wearing sunglasses, sometimes I do find the glare too bright, and as ronin quoted, makes for a fun situation when walking around the garden!

Also this is where a cloudy night is welcome, if thin enough, the clouds make a good filter?

On the brightest nights, the method I favour most is to leave the main dust cap in place on the top of my telescope and remove the smaller 2" cap, yes the focal ratio changes from f/6 to f/24,  but on the big bright Moon, its not something I tend to worry about for that particular target.

Edited by Charic

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