Moon filter? Other options?

[rach2k]

Sorry to post about an already much discussed topic, but I can't really find the answer.

I saw the moon for the first time through a telescope last week, and it was stunning! Properly awe-inspiring! The first time was just around sunset on Monday. Then on thursday, it was higher in the sky, and larger...and brighter. I bought a neodymium filter (my first accessory!) as it seemed to come (mostly) recommended here. I imagine that a lot of the detail and contrast I saw was down to it. People here seem to mention it (partly) as a moon filter, but it didn't cut the brightness down to what felt like a bearable level. I could look at the moon for no more than a few seconds, and then it felt really strange when looking away for a few minutes. 

Is there anything that can cut the glare down further, without losing contrast? Or am I just weirdly overly light sensitive, to find the moon too bright to look at when it's still a couple of days from half full? This was with my eyepiece with higher magnification, a 10mm.

I have a skywatcher dobson 10". There's a plastic cap over the tube with the primary mirror , and that has an opening in it. I've found (through googling) that just removing this, rather than the whole cap, will cut down on light allowed in. How does that work though, as surely the rest of the cap will be between the secondary and the primary mirrors? 

[knobby]

Just rotate it so the opening is between the spider vanes and it will be fine , give it a whirl, its free ... Also , whacky but try sunglasses

[John]

If you leave the cap on and just use the small hole you will reduce the brightness, contrast and resolution of the scope to that of around a 2 inch aperture. So the Moon will be easier on the eye in one sense but most the benefits of your 10" aperture will be lost.

I don't find I need a filter even with my 12" scope but others may feel more sensitive about this (though you can't damage your eye) so I guess either a neutral density or polarising filter might be OK. At least that would preserve much of the potential of your 10" aperture.

[rach2k]

Really? You can't damage your eye? A friend has been warning me of the dangers of photokeratitis - a friend of his warned him about it. Admittedly googling that and moon didn't seem to turn up anything.

I'll try sunglasses (and the cap) before spending money on another filter. I read somewhere that the neodymium one lets in about the same amount of light as an ND96 one, so there'd be no point...although I may well have misunderstood.

[John]

The moon just reflects light, it does not emit any itself.

[Scott]

the only real damage the moon does is ruin your dark adaption .

[John]

the only real damage the moon does is ruin your dark adaption .

Thats true. I don't tend to go searching for faint objects when there is a bright moon in the sky though because they will be washed out and far from their best due to the moonlight.

[Grotemobile]

http://www.firstlightoptics.com/moon-neutral-density-filters/variable-polarizing-moon-filter.html

This is what I use on the moon,

& sometimes on Jupiter.

Steve.