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Hi All, 

what filters are needed  for viewing planets and nebulas etc, also are the sun filters safe ? Seen a few people that make them from Baader sheets, I’d love to view a capture the sun but do worry about it. 

With my birthday & Christmas coming up I’m always asked what can I get you Dad, 

so an idea of items to improve viewing will be a great. 

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For white light solar viewing you can either use a full aperture filter made from Baader film or if you have a refractor you can use a Hershel wedge. Don't be tempted to use one of the old solar filters that screw into the bottom of the eyepiece. 

For the moon and planets there are two filters to consider, a neodymium filter and a variable polarising filter to dim the image if necessary. 

For nebulae the two options to consider are the UHC and OIII filters. 

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1 hour ago, Ricochet said:

For white light solar viewing you can either use a full aperture filter made from Baader film or if you have a refractor you can use a Hershel wedge. Don't be tempted to use one of the old solar filters that screw into the bottom of the eyepiece. 

For the moon and planets there are two filters to consider, a neodymium filter and a variable polarising filter to dim the image if necessary. 

For nebulae the two options to consider are the UHC and OIII filters. 

What he said ☝️

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I have referenced this to great effect https://www.cloudynights.com/articles/cat/user-reviews/accessories/astronomical-filters/filter-performance-comparisons-r1471#top

I have used a UHC filter on jupiter to great effect, really help add contrast and enhance colour.

One thing worth taking note of is that O-III filters are generally more effective on 6" scopes and above, on smaller apertures stick with a UHC.. Don't buy a cheap and nasty one off ebay. Look into them by reading reviews. 2 of mine are astronomik although the price of these is astronomical, especially at 2".

I also have a baader UHC=S however which is very utilitarian and is the one I have used on Jupiter to great effect but the Explore scientific range are supposed to be pretty good for the price tag if you are on a budget.  https://www.firstlightoptics.com/uhc-oiii-visual-filters.html

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Generally I agree Steve but I have found O-III filters work very well in smaller aperture scopes - down to 80mm. Quite spectacular views of the Veil Nebula with my 102mm refractor and good quality O-III filters. A UHC is a very useful tool as well of course but an O-III seems to make quite a few nebulous targets "pop" more in the eyepiece IMHO especially planetary nebulae and super nova remnants.

 

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2 hours ago, John said:

Generally I agree Steve but I have found O-III filters work very well in smaller aperture scopes - down to 80mm. Quite spectacular views of the Veil Nebula with my 102mm refractor and good quality O-III filters. A UHC is a very useful tool as well of course but an O-III seems to make quite a few nebulous targets "pop" more in the eyepiece IMHO especially planetary nebulae and super nova remnants.

 

I have never tried a O-III in anything less than 10" tbh John, so I will have to defer to your greater experience on this.  When I first got interested in nebula, I did a lot of research on many forums and other sites and the opinion or advice from most was 130 to 150 minimum aperture for O=III. I played safe when saying 6".

However using a frac you have no loss for a secondary, I doubt a 102 mak or newt would carry it off anything like as good as a 102 frac as used by yourself. So mny considerations.

So it would also depend on what type of ota you are using and not just aperture.  I cant remember the stats for light gathering loss for maks and newts when compared to a frac. 

TonyHaz I think it would be very helpful if you could advise what scope you are using as this will help give more specific advice to your needs.

 

 

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30 minutes ago, Davey-T said:

One thing I found with O111 it needs a dark sky to start with ( using 6" refractor )otherwise I just get nowt to see :grin:

Dave

Not the same as my experience interestingly. With my 102mm refractor (for example)- the Astronomik and Lumicon O-III filters show plenty of background stars, dimmed a bit but still present, and objects such as the East & West Veil segments and the Owl nebula with significantly more contrast than with a UHC and much, much more than with no filter at all. My back yard skies are OK but nothing special.

For a few years my only deep sky filter was an Astronomik O-III and it did everything I could wish for on nebulae with the 102mm - 250mm aperture scopes that I owned then. I had previously owned good UHC filters which made a difference, but not as much of a difference as the O-III made.

I showed my society mates the Veil Nebula using the Lumicon O-III filter, my ED120 refractor and a nice low power wide field eyepiece a couple of months back and they were rather amazed by the views.

I have also read such advice against using O-III filters with scopes of less than 200mm but I have to say that, based on my personal experience, I disagee with it :smiley:

The issue with a small mak not being as effective with such filters might be more to do with the exit pupil than the aperture of the scope or the central obstruction. Narrowband and Line filters (eg: UHC, O-III and H-Beta) perform more effectively within a certain range of exit pupils which the long focal length of mak might not deliver.

 

 

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was just editing my previous post as you posted John. 

Can I ask you did any of your buddies struggle with the reflection or eye placement when using the filter?

Only reason I ask is I have showed a few friends the benefits of O-III and some couldn't get to grips with the filter. Thinking back I am not sure 1 or 2 said they could but weren't being honest. 

 

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I usually have the filter on the end of the eyepiece barrel or (less often) on the end of the 1.25" - 2" adapter. I agree that with the filter in place, internal reflections can sometimes be more prevelant - this effect seems to be reduced by keeping the filter as close to the focal plane of the eyepiece as possible. For that reason I don't tend to put filters on the end of the diagonal barrel, for example. I also think that eyepiece eyecups should be positioned and working effectively to keep stray light off the top lens of the eyepiece as far as possible.

 

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I was just thinking about general light reflection tbh John. The surface as you know is very reflective due to the light inhibiting qualities of the filter. I found out for myself on first use this was very strange and difficult to get used to.

It was a 3/4 moon night and I was on the ring, as I looked into the EP the light reflected from my glasses onto the filter and then I had a glare which I then had to get my head around.  Took me a while to get used to this and have experienced it a few times when viewing with glasses on where light pollution is an issue. 

On the above mentioned night I offered the other observers (6 of us I think) chance to view with the O-III and at least 2 others struggled with it. 

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My Celestron, cased, eyepiece and filter set, came as a deeply-discounted offer associated with my Skymax 127mm Mak. purchase (OVL offer). The Plossl eyepieces get a fair amount of use, but the coloured filters rarely leave the case, and the Moon filter slightly more often. I have added a UHC.

I wear glasses to correct significant short-sight, and tend to wear them to set-up and align on targets, and then remove them for observing. My telescope optics have anti-reflective coatings; my glasses do not; and this is very obvious with an off-axis Moon.

Geoff

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What no-one has mentioned yet, is that you don't need any filters too see planets or nebula, they only enhance the view.

There are some nebula that respond better in certain wavelengths,  and for that, the advice above is top notch. 

For planets, different people have varying degrees of success with coloured filters to tease out certain detail. 

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44 minutes ago, rockystar said:

I should also say, that there are also a few nebula where a filter makes all the difference between seeing and not - but as a beginner,  I wouldn't worry about those to start with,  as thereis plenty up there

I agree but the Veil Nebula is, IMHO, worth the price of a filter on it's own. Without a filter there is little to see, nothing really in smaller scopes. With an O-III and a reasonably dark sky you can explore the segments of this fantastic complex of objects - several NGC's plus other bits and pieces :smiley:

All this can be yours !:

https://www.skyandtelescope.com/astronomy-blogs/explore-night-bob-king/explore-veil-nebula/

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I remember myself and a buddy viewing orion at a dark site on a fantastic clear sky with great seeing conditions and for both of us that night, the views of it were spectacular when viewed through my astronomic O-III. 

It changed from the non filtered, beautiful smoky wonder of the night and grew from filling about a half a degree in my 1 degree fov eyepiece to completely filling it with filaments of energy, shades and sharp edges. It honestly looked almost 3D. 

As john says, the cost and use of these is easily justified when you get results like that.

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21 hours ago, John said:

Not the same as my experience interestingly.

Probably because I've got so much LP in my back garden it's impossible to get eyes dark adapted :grin:

Lumicon O111 works well at dark sites.

Dave

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12 minutes ago, Davey-T said:

Probably because I've got so much LP in my back garden it's impossible to get eyes dark adapted :grin:

Lumicon O111 works well at dark sites.

Dave

Have you tried a towel over your head Dave? Looks daft, but does work!

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1 minute ago, Stu said:

Have you tried a towel over your head Dave? Looks daft, but does work!

I can't stand in the garden for 20 minutes with a towel over my head waiting :D I have tried pulling my bobble hat down over my eyes and snoozing for a bit then sticking my head under the cover which works OK.

Dave

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7 hours ago, Davey-T said:

I can't stand in the garden for 20 minutes with a towel over my head waiting :D I have tried pulling my bobble hat down over my eyes and snoozing for a bit then sticking my head under the cover which works OK.

Dave

How about a pirate patch? Aarrrggggghhh, me hearties! ;)

 

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I do use the Optolong CLS/UHC/OIII for.visual duties, great price, around 50eur in ebay. Even I have taken pictures with the uhc. This last one is my first option to use with all my scopes from the ed72 to the ES12 dobson

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