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2" Barrel


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I am in the process of upgrading my eps.  My short-term goal is 3 eps - 6mm Delos, 13mm Nagler T6, and 26-ish mm.  The low power eps that I am interested in have 2" barrels and the medium and high power eps have 1.25" barrels.  I don't care to purchase new 2" filters, so, I guess my question is - would one typically be using the 26mm ep over the other two to view any of the nebulae or any other objects that are enhanced with a filter?  Alternatives? 

Keep in mind that I am a rookie!

Scope is a 10" Dob f4.7

Thanks

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Nice telescope, and WELCOME to SGL. :)

I'm not a filter user, but typically there is much hype about 2" EPs. I use my one and only, for immersion wide field use, ie get more in. But some of the v/good 1.25" can have even wider fields. (I love my 2" 32mm EP)

The problems with nebulae for me, is that no matter what, visually I will never see the colour that can be gleaned from AstroPhotography, our human eyes simply don't transpose the wavelengths.

If you are looking to use filters for whatever reason visually, apart from LP reducing I wouldn't bother, however for AP........with a big Dob I still wouldn't bother, the mount is not designed for AP.

With a 10", I would look for even shorter, 32 - 40mm 2"EP for an immersive  wander around the sky.

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Proto Star, I'm just interested in viewing, for now.  Later on, I might get a different scope for AP.  Yeah, from what little experience I have, the UHC filter doesn't produce dramatic results.  However, I've only used it on a couple of objects. 

What are some good 1.25" LP eps with wide fields?  I don't have an abundance of cash, but don't mind spending a little to get good quality.

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UHC and O-III filters are very effective on some nebulae - dramatically so on a few such as the Veil nebula.

With an F/4.7 scope you want wide fields to be of pretty good quality so the stars stay reasonably well defined across the field of view. In the 1.25" fitting the 24mm Tele Vue Panoptic is one of the very best and would be on par, quality wise, with the Delos and Nagler that you are also planning to get. More saving though as the Panoptic is an expensive eyepiece, as are the Delos and Nagler of course.

An alternative might be to look at less expensive but still well regarded eyepieces such as the Explore Scientific ranges which can still cope with an F/4.7 focal ratio pretty well.

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UHC and O-III filters are very effective on some nebulae - dramatically so on a few such as the Veil nebula.

With an F/4.7 scope you want wide fields to be of pretty good quality so the stars stay reasonably well defined across the field of view. In the 1.25" fitting the 24mm Tele Vue Panoptic is one of the very best and would be on par, quality wise, with the Delos and Nagler that you are also planning to get. More saving though as the Panoptic is an expensive eyepiece, as are the Delos and Nagler of course.

An alternative might be to look at less expensive but still well regarded eyepieces such as the Explore Scientific ranges which can still cope with an F/4.7 focal ratio pretty well.

I was actually looking at the 27mm Pan, which is a 2".  If I calculated right, it adds 0.17* fov over the 24mm 1.25".  Is that a big deal and would there be any other disadvantages?  They are all about the same price, I just want to get the best piece without needing to buy more filters.

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My choice of EPs for your  scope ( possibly my future upgrade, but more likely a 12" ?)  could be the 6mm and  17.3mm Delos and possibly a Panoptic of 35mm, that is if I were to stick to a 3 EP set-up.  A 6mm & 13mm would be too close, should I  ever opt for a Barlow, as a cheaper upgrade, over a new EP!

With my present  signature EPs I enjoy the 32mm but wouldn't dream of filtering the EP. I would only use a filter for visual use, just to enhance the specific features,  and I frame my subjects quite tight, so an #80A Blue for Jupiter for example, using my 6mm SPL or 5-8mm BST's would, in my books,  be suitable. There isn't much up there, large enough to fill that field of view, that would look good under a 70° afov view for my purpose.

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FWIW, I went the other way - I got a 2" to 1.25" adapter that could take a 2" filter, so I could get and use 2" filters with my 1.25" eyepieces. My 2" OIII filter cost a fortune - bit it's very good, and now I can use it with any of my eyepieces. 

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I was actually looking at the 27mm Pan, which is a 2".  If I calculated right, it adds 0.17* fov over the 24mm 1.25".  Is that a big deal and would there be any other disadvantages?  They are all about the same price, I just want to get the best piece without needing to buy more filters.

If you are going to go to 2" you will want to use 2" filters, believe me :wink:

I follow the same path as Andy and use an excellent quality 2" filter with 2" and 1.25" eyepieces using either the threads on my 2" diagonals to hold the filter when using refractors or the thread on my 2" to 1.25" adapter whem using my newtonian. When I'm using 2" eyepieces I use the filter filter directly on the barrel of the eyepiece with the newtonian.

The Panoptic 27mm is a fine eyepiece though.

I only use filters for nebulae enhancement myself - an O-III filter generally.

With an F/4.7 focal ratio I would be limiting my max focal length eyepiece to 30mm to keep the exit pupil at an effective size.

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Nice telescope, and WELCOME to SGL. :)

I'm not a filter user, but typically there is much hype about 2" EPs. I use my one and only, for immersion wide field use, ie get more in. But some of the v/good 1.25" can have even wider fields. (I love my 2" 32mm EP)

The problems with nebulae for me, is that no matter what, visually I will never see the colour that can be gleaned from AstroPhotography, our human eyes simply don't transpose the wavelengths.

If you are looking to use filters for whatever reason visually, apart from LP reducing I wouldn't bother, however for AP........with a big Dob I still wouldn't bother, the mount is not designed for AP.

With a 10", I would look for even shorter, 32 - 40mm 2"EP for an immersive wander around the sky.

I find UHC and OIII filters very useful under the right conditions. Ironically, I think that if you are not very well dark adapted, they are of less benefit and can even dim the image too much. I do not find them that much use at home because it is very hard to get properly adapted given the LP levels.

I actually get best use out of my OIII when I get out under dark skies with a 4" frac and a widefield 2" eyepiece eg 31mm Nag. Under these circumstances objects such as the Veil and North America nebula look fabulous, as do other smaller objects such as M57 and 27.

Of course, you never get photographic images visually, but can still get some pretty amazing views

The 24mm Panoptic would be quite a good compromise option though if wanting to stick with 1.25" eyepieces and filters

Stu

Sent from my iPhone using Tapatalk

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I already own a UHC filter, a variety of colored filters, and a 13mm Nagler (en route), all of which are 1.25".  So, at this point, I guess something in a 1.25" will be in order.

I appreciate the input.

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