Baader Mark III Hyperion Zoom and 2" Light Pollution Filter

[bwells]

I have been reading so much about Astronomy and imaging.  My wife and I got an Celestron Edge HD 800 for a Christmas present to each other and then ended up never finding time to learn it and use it properly.  A combination of our lack of time plus needing good skis and tolerable weather ended up pushing us to just this year to finally get the telescope out.  for several months, I have been cramming to learn as much as I can about the wonderful new hobby. 

I have master many things with my telescope!  I have successfully aligned the scope using polar alignment and the 2 start alignment and calibration stars and using the All-Star Polar Alignment.  I am using my Canon 50D, paired with the Hyperion Mark III Zoom doing eyepiece projection photography.  I also did some Prime photography as well.   

I have had success using PHD Guiding and I have gotten a few decent photos of the moon and the Eagle Nebula.   The problem I ran into was light pollution from the town a few miles from my home.  Even though I am in Old Town, Maine, from my yard, the slice of sky I get is west and sits right on top of Bangor.   So when my exposure times got up to 3 minutes or more, the sky has an off-yellow glow.   So that prompted me to consider trying the Orion SkyGlow Imaging Filter.  I have a new 2” Skyglow filter and this is where I am stuck.  So, let me as a few questions to help me keep up my momentum!

• My star diagonal is 1.25” and I am using the 1.25” nosepiece.  So one thing I have read is that I cannot use the 2” filter with the 1.25” nosepiece on the Hyperion Mark III.  But I wonder if that problem still exists.  I am not even getting to the point where that issue is apparent to me yet.  When I remove the 1.25” nosepiece cover and ring behind the nosepiece cover, I get to a point where I am nervous about trying to unscrew anything more, but with the nosepiece protruding out, there is no way I can insert a 2" filter.   The next “thing” looks like it *should* come off, but turning it shows it just spins and does not actually get any looser or unscrew.  Can someone tell me how I can put a 2” filter into the Hyperion Mark III using the 1.25” nosepiece?  Or tell me this will not work so do not bother. 
• A more general question I have is how do you recommend I use filters with my setup?  For now, I am wanting to use the Orion Skyglow light pollution filter, but there are plenty of other files I would like to use.  I am not clear if I should use 1.25" or 2" filter with my Celestron 8" Edge HD.  Then, if I select a filter, how to I use the filter when I am doing  prime photography, eyepiece projection or a-focal photography?  I understand most of the equipment I have and how it goes together.  I can see how using a 2" diagonal would improve the strength for using my camera.  But I do not know if I should pursue finding a way to use a 2" diagonal or not.  When I do imaging, I am making sure my camera is positioned so it is up right and not hanging off the mount. 

So, I was about to return the 2” filter and get a 1.25” instead, but I wanted to be absolutely sure I cannot use the 2” before I return it.  I read that if I use a 1.25” filter for imaging, I will see vignette around the edges.  But I have no idea if that would really be noticeable and matter to me in the scheme of things.

Thank you for your help!

Here are a couple of my first shots using my system over the past two weeks, as I continue to learn and work the kinks out.

Also, I am attaching photos of the eyepiece to show you what I am doing and seeing to help me understand what I should and should not try to do.

Bryan

[brantuk]

The bit you want to unscrew is on an opposite thread and it is tight cos it holds everything in the main body - so don't point it down when it does come off. If you hold the field stop ring when undoing it - it undoes quite easily and allows you to fit a 2" adaptor which has an internal thread for 2" filters. Hth