Multispectral StarlightLive Captures Step-by-Step

[Robrj]

Very nice Martin!  My wife just looked at it and said "oh oh, more gadgets!"

Which adapter is that?

[Martin Meredith]

The adaptor is this one from TS but I imagine there are equivalents nearer to home. Note that with the SX filter wheel you have to also specify the right adaptors when buying the filter wheel itself (they come as part of the deal). I asked for T adaptors front and rear. I use a T to 2" tube to connect the filter wheel to the drawtube.

Martin

 

 

[Robrj]

On 12/2/2016 at 22:39, Robrj said:

I bought the Orion Extra Narrowband Set (Ha, OIII & SII).  I don't have a filter wheel.  I'll just be doing it manually for now.  I have a newtonian so I don't think a filter wheel will work. 

I posted this on CN as well:

I had my first go at Multispectral EAA with Starlight Live and the Lodestar X2.
Orion Skyview Plus on the AVX, 0.7x focal reducer and filters (S-II, H-Alpha, O-III)

NGC 2392, the Eskimo Nebula  (SHO) 15x10s S-II, 15x10s Ha, 10x10s O-III

Since I don't have a filter wheel, the biggest challenge was making sure the camera was in the same orientation after changing the filter. I put a parfocal ring on it so I could get the same depth in the focuser.  My method was to pause the camera, bring up the focus tool and zoom in on my object and make note of it's position.  I would take the camera out, change the filter and then put it back in and adjust the position (roll the camera) so it was close to what I remembered.  I also took the opportunity to focus it.  I wanted to have them all be the same exposure but on O-III, I could only get 10 stacks.  I tried going back to the focus tool to refocus or reorient the camera but it only got me a couple more stacks.  It was pretty dewy out as well.  I noticed a lot of it on my secondary when I broke down for the night.  
 

[Dom543]

Rob,

From here everything will be only easier. Martin uses a filter wheel with his Newtonian and a photo of his setup is on the last post of the first age of this same thread. I use a manual filter drawer from TS that requires only 15mm back focus. If you attach a T-threaded 1.25mm eyepiece holder (also available from TS) on the camera side, then you can push the Lodestar very close to the filter. I am sure that you will be able to reach focus.

Good luck!  --Dom

[Robrj]

I bought a cheapo 3 position filter wheel from Amazon for $30 and gave it a run last night along with my Celestron 70mm Travel Scope on my SLT mount.    Focus seems good through the filter wheel and holds when I switch filters.  I just have to be careful not to move it too abruptly as the focuser isn't that good and can move.  I was having issues with stacking so these took quite a while to get.  I'm thinking it might be the mount.  I could usually get one channel to stack but when I switched to a different filter on a different channel, it wouldn't continue the stack.  If I reset the stack and restarted with the new filter, it would stack until I changed filters again.  But eventually it started working.    I also had to constantly remind myself which filter was in which position.  My wheel isn't numbered so I'm going to have to mark it in some way to help me tell which filter I'm using. 

Here are two M42 done with the Lodestar X2M and the filter wheel.  Exposure details are on the "Technical Card"

HOO

 

SHO

 

 

[roelb]

On ‎29‎-‎12‎-‎2016 at 21:09, Robrj said:

I bought a cheapo 3 position filter wheel from Amazon for $30 and gave it a run last night along with my Celestron 70mm Travel Scope on my SLT mount.    Focus seems good through the filter wheel and holds when I switch filters.  I just have to be careful not to move it too abruptly as the focuser isn't that good and can move.  I was having issues with stacking so these took quite a while to get.  I'm thinking it might be the mount.  I could usually get one channel to stack but when I switched to a different filter on a different channel, it wouldn't continue the stack.  If I reset the stack and restarted with the new filter, it would stack until I changed filters again.  But eventually it started working.    I also had to constantly remind myself which filter was in which position.  My wheel isn't numbered so I'm going to have to mark it in some way to help me tell which filter I'm using. 

Here are two M42 done with the Lodestar X2M and the filter wheel.  Exposure details are on the "Technical Card"

HOO

 

SHO

 

 

Fine details...

[Robrj]

I managed to snag a used 7-position Starlight Xpress USB filter wheel (T-thread)  about 6 minutes after it was posted for sale! 

[MrOD]

Robrj your M42 reminded me some of my first eaa experiences. ETX-70, Analog cctv, like 50m of wires and tons of fun

And now we have such wonders like SLL and digital cams - pure magic.

PS. Just realised this is multi-spectral thread - sorry

[RobertI]

On 30 January 2017 at 15:21, Robrj said:

I managed to snag a used 7-position Starlight Xpress USB filter wheel (T-thread)  about 6 minutes after it was posted for sale! 

Congratulations on your purchase! I bought a 5 position and wished i'd bought a 7 position. I look forward to seeing more multispectral results.  

[Guest]

Fantastic guide , thank you so much.. I must try same with my C9.25 + Alan Gee Telecompressor Mark II and my SX LODESTAR..

Cheers

 

Martin

[Robrj]

On 12/3/2016 at 00:40, Martin Meredith said:

Hi Rob

I use a filter wheel with my Newt. Focus is a bit tight if I screw the Lodestar on to the FW directly, so instead I use an adaptor that allows me to slide the sensor as close as I can to the FW and it is now fine, with plenty of focus range, at least for this Newt.

I started with a manual wheel but bought the 7-position SX wheel over the summer and haven't looked back. Manual is fine but the USB controlled wheel makes it much faster to gather data (and no chance of moving/vibrating the scope). If you do go in this direction I'd choose one with the largest number of filter slots you can as they all have their uses e.g. I use one covered with a piece of flocking (Don's suggestion) which allows me to take darks without getting up. 

Martin

 

I stuck my filters (S-II, H-Alpha, O-III, Optolong CLS-CCD) in the filter wheel.  Since I really didn't have a filter to sacrifice for darks, I purchased a  dark blank from Scopestuff ($17) (http://www.scopestuff.com/ss_dfr1.htm).    I have two slots left.  Any recommendations for the final slots?  I'm thinking,  just leave one open for non-filter shots.

[Martin Meredith]

Congrats Rob. If you're interested in spectroscopy, you could add a suitable grating to one of the slots. I have one but the weather has been foul recently and no chance to try it out. The open idea is good but if your other filters (or some subset of them that you'll use a lot) are parfocal, it is worth getting a clear filter that is parfocal with them, otherwise you'll be refocusing (e.g. if you want to overlay straight-thru mono with H-alpha, which is fun, you'd find yourself refocussing). Other options: if you fancy doing some photometry, you can get B and V filters. I'm short of slots since I keep the RGB in all the time in case I come across a nice cluster.

Martin

[Robrj]

1 hour ago, Martin Meredith said:

Congrats Rob. If you're interested in spectroscopy, you could add a suitable grating to one of the slots. I have one but the weather has been foul recently and no chance to try it out. The open idea is good but if your other filters (or some subset of them that you'll use a lot) are parfocal, it is worth getting a clear filter that is parfocal with them, otherwise you'll be refocusing (e.g. if you want to overlay straight-thru mono with H-alpha, which is fun, you'd find yourself refocussing). Other options: if you fancy doing some photometry, you can get B and V filters. I'm short of slots since I keep the RGB in all the time in case I come across a nice cluster.

Martin

Would a clear filter be the same as a luminace filter?  I have an Astronomik L filter that I use with the ASI185MC and the Orion 50mm to reduce star bloat.

[Martin Meredith]

Hi Rob

The different between the Luminance and Clear, at least for the Baader filters, is that the former restricts IR and UV. I guess the idea is that the band edges match those of the R and B filters when doing RGB imaging.

See here for a response figure comparing the filters.

Since I use a reflector I tend to use Clear when observing galaxies in mono, although I imagine there are some advantages to using the Luminance to reduce bloat for an achromat, say. 

Martin

 

[Robrj]

I gave my filter wheel it's first light last night.  SOOOO much easier.  I love it.  Orion Skyview Pro 8" 

M42 in SHO (S-II:10x30s, Ha:60x5s, OIII: 60x5s)

M42 in HOO (Ha:43x5s, OIII:60x5s)

partial Rosette Nebula in SHO (S-II:5x60s, Ha: 5x60s, OIII:5x60s)
 

M1 in SHO (S-II:10x30s, Ha:10x30s, OIII:10x30s)

partial of IC443 in SHO (S-II:10x30s, Ha:10x30s, OIII:10x30s)

[RobertI]

Some great result there, I love the Crab! 

[Martin Meredith]

Glad you're enjoying the filter wheel. It really is so much easier than a manual one. The Crab is one of the few things I've found so far which has enough sulphur to make S-II a worthwhile purchase (well, my excuse is that it came with the narrowband set)! Another benefit of narrowband is reducing the star saturation, nicely demonstrated in your M42.

I'm waiting for clear night to get my RGB filters working on the Puppis open clusters.

Martin

 

[Robrj]

Here's a multispectral shot I did of the Tadpoles in IC410 (10x30s in each filter: S-II, H-alpha, O-III):

 

I'm looking for a simple way to focus and/or plate solve with narrowband filters.  I would like to be able to jump to a clear filter and plate solve or focus and then go back to the narrowband (mostly plate solve without focusing).  I tried a clear filter but it doesn't seem to focus at the same point and Orion doesn't sell a clear or luminance filter that's parfocal with their narrowband set (at least not that I'm aware of).  Would putting a short extender on the clear affect the focus (e.g. 1/4" extender) to where I might be able to make it parfocal?  What do you guys do?

[stash_old]

10 hours ago, Robrj said:

Here's a multispectral shot I did of the Tadpoles in IC410 (10x30s in each filter: S-II, H-alpha, O-III):

 

I'm looking for a simple way to focus and/or plate solve with narrowband filters.  I would like to be able to jump to a clear filter and plate solve or focus and then go back to the narrowband (mostly plate solve without focusing).  I tried a clear filter but it doesn't seem to focus at the same point and Orion doesn't sell a clear or luminance filter that's parfocal with their narrowband set (at least not that I'm aware of).  Would putting a short extender on the clear affect the focus (e.g. 1/4" extender) to where I might be able to make it parfocal?  What do you guys do?

Hi Have you tried using something like Astrotortilla on the above pictures using a dummy mount on something like CDC - you will need to place CDC somewhere near the object  - If Astrotortilla can plate solve then ,assuming it can control your mount this will give you a "platesolving" route. Important to set up the software correctly in terms of FOV etc and the number of Cat files (some of which are large). I dont use it now, Use Platesolve that is integrated with APT, but I had good plate solving with 20secs  - just a thought !!   Maybe a future upgrade to Pauls Software :-)

[Robrj]

On 3/3/2017 at 02:45, stash_old said:

Hi Have you tried using something like Astrotortilla on the above pictures using a dummy mount on something like CDC - you will need to place CDC somewhere near the object  - If Astrotortilla can plate solve then ,assuming it can control your mount this will give you a "platesolving" route. Important to set up the software correctly in terms of FOV etc and the number of Cat files (some of which are large). I dont use it now, Use Platesolve that is integrated with APT, but I had good plate solving with 20secs  - just a thought !!   Maybe a future upgrade to Pauls Software :-)

I use Astrotortilla with APT.  I have the basic version of APT and didn't realize that it has plate solving built in.  My setup connects Astrotortilla with APT.  When I click solve, it grabs the image from APT.  The issue I think is that it's dimmer when I use it with one of the filters so I don't get many stars, especially with the lodestar.  It plate solve fine with a filter like my Optolong CLS-CCD filter but extra narrowband filters are tough and the results are mixed.  Sometimes it solve fine but others it fails quite a bit regardless of my sigma settings (low object registration).  Focus with a Bahtinov mask is tough too as it's very dim and hard to see the spikes.

[stash_old]

21 hours ago, Robrj said:

I use Astrotortilla with APT.  I have the basic version of APT and didn't realize that it has plate solving built in.  My setup connects Astrotortilla with APT.  When I click solve, it grabs the image from APT.  The issue I think is that it's dimmer when I use it with one of the filters so I don't get many stars, especially with the lodestar.  It plate solve fine with a filter like my Optolong CLS-CCD filter but extra narrowband filters are tough and the results are mixed.  Sometimes it solve fine but others it fails quite a bit regardless of my sigma settings (low object registration).  Focus with a Bahtinov mask is tough too as it's very dim and hard to see the spikes.

Actually there are 3 plate solving routes in APT - Astrotortilla,Platesolve and All Sky plate solver - the latter 2 are called from within APT if you have the mount connected to APT. Not sure which version they are in but at £19 per year its a bargain(of course you dont need to buy it every year!). With the APT inbuilt Platesolve  I now get my solving down to about 7s using SSD, managed Cat files, but it will also do "blind solving" but takes a lot longer as it doesn't have a starting point(DEC/RA of your scope). Sounds like you need a filter wheel and do plate solving using the clear(none) filter. However as you say it doesnt work every time but its better than me at looking at a sky map   Best of all it repositions the object in the centre of FOV.

[Robrj]

On 3/5/2017 at 05:01, stash_old said:

 Sounds like you need a filter wheel and do plate solving using the clear(none) filter. However as you say it doesnt work every time but its better than me at looking at a sky map   Best of all it repositions the object in the centre of FOV.

I have the Starlight Xpress USB filter wheel and a clear filter.  The problem is the filter isn't parfocal with the Orion Narrowband filters, requiring a refocus if I want to plate solve and then again to see the object through the narrowband filters.  I picked up a 1/4" adapter but it makes the filter too thick and it won't fit in the wheel.  I'm going to try and build the Arduino Nano focus controller mentioned on this forum.  Seems like that might be the best, low-cost way around the problem.  I have all the parts now, I just need to put it together.

[Robrj]

Did some more multi-spectral last night.  Orion Skyview Pro 8"/AVX w/Lodestar X2M

NGC 2359 SHO (5x60s each channel)  (Thor's Helmet)

NGC 2359 HOO (5x60s each channel)

NGC 2348 HOO (9x20s each channel)  (Planetary Nebula in M46)

NGC 2348 SHO (9x20s each channel)

NGC 1931 HOO (5x60s H-Alpha, 4x60s O-III) (the mini-Orion Nebula or the Spider)

NGC 1931 H-alpha (5x60s)

IC 417 H-alpha (5x60s) (the Fly)

[Martin Meredith]

Very impressive given the conditions moon-wise! I struggled with Thor's Helmet.

Martin