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#1 Tom Andrews

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Posted 30 October 2012 - 10:23 PM

I'm 100% video astronomy now and want to buy filters. I've never owned/used filters so I've been researching this forum and the CCD imaging forum to see what people are using. There seems to be a wide array of filters used.

I have the Mallincam Xtreme and 3 scopes: C11, Meade 8" EMC OTA and an Orion SkyViewPro 5" Mak. I'm not interested in imaging other than taking snapshots of the objects I'm viewing. I'm willing to buy as many as needed to cover the gamut of object viewing. I live in an orange zone.

I'm leaning toward the IDAS filters: LP (P2), Nebula (V4) and UV/IR.

The Lumicon versions are less expensive though have slightly different options: Deep Sky, UHC, OIII, H-Alpha, H-Beta, IR.

Then there is Astonomik.

Is there an advantage to spending about the same amount of money and getting the more individualized Lumicon or others' filters? Or do I have no idea what I'm asking which would not be surprising since I know very little about filters?

And does anyone recommend any others?

Thanks!

#2 wolfman_4_ever

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Posted 30 October 2012 - 11:59 PM

Have you read Jim Thompson's wonderful article on Filters and Video Astronomy? (google)

Your not going to use just one.. been there done that.. Full moon? Visual HA, IR Pass, Deep Red... Nebula? Visual OIII, HB, HA Just LP? IDAS, Deep Sky, UHC, Astronomic UHC, UHC-S, Baader, etc. Galaxies? IR pass UV Cut, LP filters Clusters? UV and IR cut.. etc, etc, etc..

It all depends on your object.. Galaxies have a lot of IR.. Bright Nebulas Like Veil have OIII.. etc

#3 GlennLeDrew

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Posted 31 October 2012 - 09:38 AM

With your scopes, the UV/IR filter is not needed.

A good light pollution filter which 'notches out' the principal emission lines of sodium and mercury light, while passing as much other light as is useful, is an absolute must.

For emission nebulae of lower surface brightness, a narrow-band H-alpha is really useful.

If you could find a nebula filter which passes the H-beta/O-III group *and* H-alpha, that would be the bee's knees, as then you would have access to all the important nebular emission lines, while blocking virtually all other light. But such a beast might be hard to find.

In lieu of the foregoing, a UHC type filter does pass the H-beta/O-III group, which are the emission lines which the eye sees (H-alpha is virtually always of too low surface brightness for visual detection.)

#4 biomedchad

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Posted 31 October 2012 - 10:30 AM

i have

astronomik uhc, mallincam ir, baader uv/ir and astronomik ha

#5 ensign

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Posted 31 October 2012 - 05:47 PM

I use the Orion imaging skyglow filter as a general purpose light-pollution filter. Works great!

#6 Lenbo

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Posted 31 October 2012 - 06:18 PM

Hi Tom. Most of time I use an Astronomik UHC. I also have a Lumicon Deepsky and an Orion HA and the Mallincam IR. The Astronomik is usually on the front on my MFR5 in the VRC8. I add the IR when I use the Xtreme in my Stellarvue ED70. I have a Lumicon UHC from my pre camera days but it didn't work very well with the Mallincam. Like you I am in an orange zone. Len

#7 A. Viegas

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Posted 31 October 2012 - 08:29 PM

Hi Tom,

I insert my MCX into an orion 5 position 1.25" filter wheel with Lumicon Deep sky, UHC, Astronomik h-Beta and Mallincam I.R. filter - this leaves me one open slot for No Filter viewing. Generally I think you will just have to experiment, but I have gotten good results with this batch of filters on various DSOs and in various light pollution and full-moon glow situations. I recently got a very nice Helix Nebula in H-beta and a great NGC 6960 in UHC... meanwhile i find the deep sky a great all around galaxy filter and on globulars the Mallincam IR is great. My advice is if you have any 1.25" filters already try using what you have and then just wait until something shows up on Amart or here on CN... I bought two of my filters used and frankly I regret paying full price for my other filters... If you can borrow any from friends or your local club to experiment that is not a bad idea either...

But believe me the key investment is the filter wheel... you do not want to screw on and off each filter on the MCX, for $90 its a great low cost convenience!

Cheers,

Al

Here is the Helix in H-beta -- 300 second exposure C8 @ F4 AGC at 2 no APC

Attached Files



#8 Tom Andrews

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Posted 31 October 2012 - 10:12 PM

Have you read Jim Thompson's wonderful article on Filters and Video Astronomy? (google)


Thanks Dave. I hadn't read it but I did today. A lot more depth but in the same vein as the charts found on the Lumicon, Astronomik and Hutech websites. Good stuff.

I realize that I worded my post poorly. I was looking more for which brand(s) people preferred and why. I know I'm going to need an OIII, LP, H-Beta and probably UHC. I just didn't know why people picked one brand over another. Jim's research helped answer that for me and confirm my choices.

Thanks to all the input given here, it is all useful and appreciated.

#9 Tom Andrews

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Posted 31 October 2012 - 10:45 PM

With your scopes, the UV/IR filter is not needed.


Thanks Glenn. I had read one of the recent threads on this forum (Mallincam star shapes) where UV/IR filters were discussed for star bloating. It seems that not everyone agrees with whether they help or not. I had already decided not to get one at this time. The star bloat bothered me at first until I noticed that almost every image I saw had bloated stars. However, then the recent pictures by MPGXSVCD on the Astro Video Image Gallery thread has beautiful stars, not nearly as bloated as mine. But I don't know what he's using to achieve that.

#10 Tom Andrews

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Posted 31 October 2012 - 10:51 PM

But believe me the key investment is the filter wheel... you do not want to screw on and off each filter on the MCX, for $90 its a great low cost convenience!

Cheers,

Al


Thanks Al. I guess I need to keep the wheel in mind. For now, I plan to use one filter per night and only view objects that will work best in that filter. The main reason for that is I'm viewing remotely from inside the house and I don't want to keep going out to change filters. When summer comes back around and I'm outside again, the wheel could be well worth it.

#11 GlennLeDrew

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Posted 01 November 2012 - 09:24 AM

Tom,
MPG...'s camera is a Panasonic camera with *lots* of pixels; it will deliver a vastly superior image of star dots compared to the very much coarser (but vastly more sensitive!) Mallincam.

Al,
That Helix looks like it was taken through an H-alpha, as it has the very same red as I've gotten with mine. An H-beta image should look blue-green, and of poorer contrast (dimmer) due to that emission line *always* being weaker than H-alpha.

#12 A. Viegas

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Posted 01 November 2012 - 01:41 PM

Glenn,

You are right, my mistake in typing it was h-alpha 12nm I believe...

Al






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