Moon Filter Question

[scitmon]

Hi all, 

I've been a happy owner of a SW ED80 pro for a couple of weeks now and I just want to check I'm using my 2" Baader Moon filter correctly.  When using my Explore Scientific Barlow and an Eyepiece, I am screwing the filter onto the base of the Barlow lens.  Now this is a heavy piece of kit, and when I insert it into the diagonal, all of that weight is resting on the filter.  Is this ok to do or am I using it incorrectly?

[Putaendo Patrick]

Isn't the weight being supported by the neck of the Barlow? If the bottom of the Barlow or the filter was touching something, it would be hitting the mirror of the diagonal - and I doubt this is the case.

You shouldn't have any problems (I think)

[Ant]

I agree with Patrick.

An alternative... Can the filter not screw into the diagonal? Then you have it in place regardless of the barlow / EP combo your using? 

[Louis D]

One more alternative.  Get an entry level binoviewer and a pair of 25mm/26mm plossls.  You won't need a moon filter because the light is split in two, and both eyes see the moon at the same time, so they don't get overwhelmed by the massive difference in brightness between the left eye and the right eye.  I have never seen more detail on the full moon than with a binoviewer.  It's so natural.

[Ruud]

Have you tried observing the Moon without a filter? You may find that shows you the Moon just as well.

[scitmon]

4 hours ago, Putaendo Patrick said:

Isn't the weight being supported by the neck of the Barlow? If the bottom of the Barlow or the filter was touching something, it would be hitting the mirror of the diagonal - and I doubt this is the case.

You shouldn't have any problems (I think)

No, there is a ridge in the diagonal (see pic) that it rests on. 

I can screw the filter on the other end of the diagonal that goes into the focusser, i guess that would be preferable?

 

[laudropb]

Yes. I think it is best on the diagonal.

[alanjgreen]

Yes. Thats where it goes (on the other side of the diagonal as in your last picture).

Now you can change eyepieces as often as you like and the filter remains in place all the time better than on and off, on and off in the dark!

If you buy a nebula filter then buy one that is the same size as your diagonal and put it exactly where you have the moon filter now.

[John]

10 hours ago, Ruud said:

Have you tried observing the Moon without a filter? You may find that shows you the Moon just as well.

Thats my thinking too !

I don't need or use a moon filter with any of my scopes from 4" to 12" in aperture.

[Dave In Vermont]

You can also get a 2-piece variable-polarizer as a Moon-Filter. These, by rotating the two-parts together, vary the light-reduction from 1% to 40% transmission. Then you can screw one half in the diagonal, and the other in an eyepiece. Then to vary the dimming-effect, all you need to do is rotate the eyepiece in the focuser.

This works best for me for very bright objects.

Dave

[LukeSkywatcher]

21 hours ago, scitmon said:

No, there is a ridge in the diagonal (see pic) that it rests on. 

I can screw the filter on the other end of the diagonal that goes into the focusser, i guess that would be preferable?

 

Yep. Thats where to screw in the filter (if you so decide). As Ant said above.......it leaves you the option to change EP's without having to remove the filter every time. Same rule applies for any filter you decide to use. Just dont go stacking filters. They all do different jobs and you'll be messing about with the light waves. 

[LukeSkywatcher]

15 hours ago, Dave In Vermont said:

You can also get a 2-piece variable-polarizer as a Moon-Filter. These, by rotating the two-parts together, vary the light-reduction from 1% to 40% transmission. Then you can screw one half in the diagonal, and the other in an eyepiece. Then to vary the dimming-effect, all you need to do is rotate the eyepiece in the focuser.

This works best for me for very bright objects.

Dave

This is what i do when observing the Sun with my Hershel wedge. I also use the correct ND3.0 filter (safety is paramount), and a solar continuum filter (brings out finer detail).

*NEVER attempt to look at the sun without the use of proper safety filters such as an ND filter or other types of safety filters...........you WILL damage your eyes and even risk going blind*

Observing the Moon without any filter is perfectly safe. Its just a matter of personal preference.

[John]

My moon filter is left in the eyepiece case most of the time - I don't seem to need it even with my 12" scope.

[scitmon]

Thank you all for the clarification.  I'll experiment without the filter (I wasn't really asking about that, just its positioning), I guess it depends on how much of the moon is lit as well.

[LukeSkywatcher]

17 minutes ago, John said:

My moon filter is left in the eyepiece case most of the time - I don't seem to need it even with my 12" scope.

I sent mine to live in Dallas (USA). It wasnt worth asking for any money for it, so i popped it (in its case) into a padded Jiffy envelope and sent it off.

I havent heard from it since. 

LOL.

[John]

20 minutes ago, scitmon said:

Thank you all for the clarification.  I'll experiment without the filter (I wasn't really asking about that, just its positioning), I guess it depends on how much of the moon is lit as well.

Using higher magnifications dims the Moon to a comfortable level I find.

[LukeSkywatcher]

41 minutes ago, John said:

Using higher magnifications dims the Moon to a comfortable level I find.

Not to mention closer views. Win/win.

[Dave In Vermont]

I find the filters help to 'eek' out better light/dark topography on the lunar surface - making shadows more pronounced. I wouldn't say that one should have a filter for the Moon, let your own eyes be your guide.

But the variable-polarizer works on other celestial objects than the Moon alone - as LukeSkywatcher has shown. It's also a favorite of mine for Venus.

Dancing in the Shadows -

Dave

[LukeSkywatcher]

31 minutes ago, Dave In Vermont said:

I find the filters help to 'eek' out better light/dark topography on the lunar surface - making shadows more pronounced. I wouldn't say that one should have a filter for the Moon, let your own eyes be your guide.

But the variable-polarizer works on other celestial objects than the Moon alone - as LukeSkywatcher has shown. It's also a favorite of mine for Venus.

Dancing in the Shadows -

Dave

Ive never tried my variable polarising filter on any planet (let alone on Venus, the brightest). Ive read about people using one. I know its not going to bring out any detail, but dimming the view just might allow for this. Me and coloured filters just dont dont get along. I notice no difference in anything.......apart from the colour change.

[Louis D]

1 hour ago, LukeSkywatcher said:

Me and coloured filters just dont dont get along. I notice no difference in anything.......apart from the colour change.

I've found an 82A light blue filter helped with feature contrast on Jupiter and a 21 orange filter helped slightly on enhancing contrast for dark features on Mars.  A moon & skyglow type filter on Jupiter creates some interesting effects.  I'm not sure anything looked better, but it was entertaining.  I've tried all sorts of other color combinations, but nothing else seemed to improve anything.

[LukeSkywatcher]

23 minutes ago, Louis D said:

I've found an 82A light blue filter helped with feature contrast on Jupiter and a 21 orange filter helped slightly on enhancing contrast for dark features on Mars.  A moon & skyglow type filter on Jupiter creates some interesting effects.  I'm not sure anything looked better, but it was entertaining.  I've tried all sorts of other color combinations, but nothing else seemed to improve anything.

Ive bought 2 sets of coloured filters over the years. The 1st was with my eye opener EP kit for my 90mm refractor). I gave them away. When i bought a 200mm SCT.........i bought another set and have not used then but once.

[Dave In Vermont]

I was reading some reviews of the Baader OIII-Filter last night. And I ran into a total surprise: An OIII-Filter used on Jupiter! With claimed great results.

I doubt this is dependant on the brand of OIII one uses - but as the Baader OIII has a narrow-bandwidth, I'll be able to try it with the narrowband Baader, and wider passband Astronomik OIII. I'm convinced these will produce different effects, but I'll remain objective in my experiments - as best I can - and avoid a 'winner v. loser' prize.

Dancing in the dark,

Dave