Author Topic: Which moon filter for 127mm mak?  (Read 177 times)

acoplochop

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Which moon filter for 127mm mak?
« on: December 26, 2017, 09:30:08 AM »
I have a 127mm Mak-Cass on the way.  Bought it for viewing planets, double stars, the moon, and globulars.

I have not ever possessed a moon filter before.  Looking at Agena Astro's website, they are available in different heights of filter level, 12.5%, 25%, 50%, or so I could purchase a changeable filter.

What do you all suggest?
Are the 12.5%, 25%, and 50% versions for different stages of the moon?



Roger Dixon

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Re: Which moon filter for 127mm mak?
« Reply #1 on: December 28, 2017, 02:14:46 AM »
I've found I prefer a color filter over the neutral density filters for lunar observations. I particularly like the #85B Salmon colored filter. The 85B has a 55% transmission. The #56 light green (53%) and the #21 orange (46%) also do a nice job on the moon.

Dave

lodbelimfo

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Re: Which moon filter for 127mm mak?
« Reply #2 on: December 28, 2017, 08:42:58 PM »
Quote
I have a 127mm Mak-Cass on the way. Bought it for viewing planets, double stars, the moon, and globulars.

I have never owned a moon filter before. Looking at Agena Astro's website, they come in different levels of filter level, 12.5%, 25%, 50%, or I could buy a variable filter.

What do you all suggest?
Are the 12.5%, 25%, and 50% versions for different phases of the moon?


Why are you thinking of purchasing a moon filter?

Jon

Rick Perrigo

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Re: Which moon filter for 127mm mak?
« Reply #3 on: December 29, 2017, 03:56:44 AM »
I just use a pair of sunglasses. They work perfectly, and I'm the coolest astronomer in the county!

Jason Kaltwasser

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Re: Which moon filter for 127mm mak?
« Reply #4 on: December 29, 2017, 10:17:30 PM »
Quote
I just use a pair of sunglasses. They work perfectly, and I'm the coolest astronomer in the county!


I used to do that. My wife thought I looked ridiculous coming inside at night with sunglasses on.

Unfortunately I need prescription sunglasses so the last pair I got did not seem to have the same optical quality as the previous pair so I have since gone to color filters.

Dave

David Schwartz

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Re: Which moon filter for 127mm mak?
« Reply #5 on: January 01, 2018, 02:27:31 AM »
Quote
Quote

I just use a pair of sunglasses. They work perfectly, and I'm the coolest astronomer in the county!


I used to do that. My wife thought I looked ridiculous coming inside at night with sunglasses on.

Unfortunately I need prescription sunglasses so the last pair I got did not seem to have the same optical quality as the previous pair so I have since gone to color filters.

Dave

I do not use filters for the moon, I just let my eye adapt to the brightness. But I can see there might be some use in color filters.

Jon

Pat Young

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Re: Which moon filter for 127mm mak?
« Reply #6 on: January 04, 2018, 01:40:31 PM »
Binoviewers cut down the light perfectly.

ramapali

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Re: Which moon filter for 127mm mak?
« Reply #7 on: January 08, 2018, 04:29:04 AM »
I'm using a 6inch mak at f12 and even with the slightly larger than 3mm exit pupil the moon is nowhere near being too bright that a moon filter is needed, even when full.

pregdefciato

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Re: Which moon filter for 127mm mak?
« Reply #8 on: January 08, 2018, 03:52:41 PM »
Hi.

Tried a bunch of filters, but as Jon and Gene, now I just let my eye take the hit. It's funny when going back in the house, the observing eye feels like it's been spray painted black...

For a while, I used the orange filter that came with the Celestron eyepiece and filter set. Cuts just enough light and makes it look like it's all made of cheese!

I hate to say this, $$$ wise, but that angry cat avatar above is on to something. I happened to have two cheap identical 25 'Plossl's that came with telescopes (Orion Sirius/Celestron), so I bought a Celestron binoviewer. With a large Maksutov (the 180 mm), best and most comfortable way to look at the Moon. You'd think 25 mm would be lowish magnification, but the combination of slightly longer focal length due to longer light path and two retinas processing images, I saw as much as with one 10 mm eyepiece. Now I have a single 19 mm Panoptic somewhere, all lonely...

--Christian

cormuresa

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Re: Which moon filter for 127mm mak?
« Reply #9 on: January 10, 2018, 01:03:43 AM »
Quote
Quote

Quote

I just use a pair of sunglasses. They work perfectly, and I'm the coolest astronomer in the county!


I used to do that. My wife thought I looked ridiculous coming inside at night with sunglasses on.

Unfortunately I need prescription sunglasses so the last pair I got did not seem to have the same optical quality as the previous pair so I have since gone to color filters.

Dave

I do not use filters for the moon, I just let my eye adapt to the brightness. But I can see there might be some use in color filters.

Jon

I mainly use them because I think they sharpen up the view - even with the SW120ED I find the image to be a little sharper with the 85B Salmon filter and the 56 green. The 21 orange causes a lot of finer features to really pop. As a bonus they do take the edge off the brightness.

Dave

Kyle Montes

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Re: Which moon filter for 127mm mak?
« Reply #10 on: January 10, 2018, 07:34:44 AM »
Taylor, I have a 127mm Mak and really like it for planets and the moon, and a few deep space objects. I keep mine in the garage for easy and fast setup on an Alt-Az mount.

The ND filters you are considering are a good option. The different levels of transmission are for the different phases of the moon. There are also variable polarizing filters, but I did not find the detail as sharp as the NDs. Color filters are another option, and I have used them before. I have also tried sunglasses but just didn't like using them. Of all the filtering options I have tried the ND filters gave me the sharpest and views and good contrast enhancement.

For the past several years what I have been doing to observe the moon is to turn on the backyard lights. I even do that for observing Jupiter and Venus. As a bonus, not being dark adapted allows the eyes to see color much better. The moon does have color, albeit very subtle.

Enjoy your Mak, they're great little instruments.

Ed D

Edited for clarity of content.

John Abreu

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Re: Which moon filter for 127mm mak?
« Reply #11 on: January 11, 2018, 03:52:35 PM »
Quote

Ed:

I am confused here. First you say that now that you just turn that n some lights so your eyevis no longer dark adapted and then you say the moon is too bright to observe with in large scopes..

The moon is no brighter in my 25 inch than it is in my 4 inch, its just larger. The eye naturally adapts to the brightness.

Jon

Roger Evans

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Re: Which moon filter for 127mm mak?
« Reply #12 on: January 12, 2018, 07:13:52 PM »
Quote
Quote

Quote

I just use a pair of sunglasses. They work perfectly, and I'm the coolest astronomer in the county!


I used to do that. My wife thought I looked ridiculous coming inside at night with sunglasses on.

Unfortunately I need prescription sunglasses so the last pair I got did not seem to have the same optical quality as the previous pair so I have since gone to color filters.

Dave

I do not use filters for the moon, I just let my eye adapt to the brightness. But I can see there might be some use in color filters.

Jon

I don't use a moon filter either. I guess, I am too lazy to put it on. But this is what happens to me when I don't use any filters for the bright objects: after looking through the eyepiece for about a minute or two, and when I move away from the scope, I see a dark spot in my vision. Is this normal? It's like looking at a bright flashlight straight on. A dark spot is there for about 30 seconds or so then it is disappear.

William

Yung Pryor

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Re: Which moon filter for 127mm mak?
« Reply #13 on: January 13, 2018, 02:07:31 AM »
I've tried looking at the moon before without a filter, in several scopes, 120ED, C8, C5, its painful. It may work for some, but not for me.
Thanks for the feedback all. All of those filters are relatively inexpensive, I'll give some of them a try and see which works best.

curnarenche

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Re: Which moon filter for 127mm mak?
« Reply #14 on: January 13, 2018, 02:28:01 AM »
Hi.

A few related comments:

--William: here's what I wrote earlier:
"(...) now I just let my eye take the hit. It's funny when going back in the house, the observing eye feels like it's been spray painted black..." So don't worry.

--Taylor: a variable polarizer is two filters stacked. I bought a 40$ one, and it makes a ghost image of the Moon. So to add to Ed's comment, a good one might cost more--be warned.

--The regolith that is on the Moon surface is a fine dust but still rough on a small scale and acts like retroreflective paint (but not via the same mechanism: 'shadow hiding' vs transparent beads). This gives rise to the 'opposition effect' where the full Moon is brighter, as much as +40%, than one would expect just from the geometry of a smooth surface. So for some people, a filter might be better on those nights.

--People often recommend a green or orange filter when observing low-contrast detail on the Sun in white light, to reduce chromatic effects from optics, atmosphere(s), eyes, ???... Such a filter might help too for the fuller phases of the Moon, as others have stated. I think this makes a strong case for a yellow/orange filter.

--Christian