Filter positions

[TheDecepticon]

Hi!:D

I want to get into narrow band, love the colours etc, so I want to use my LRGB 5 position filter wheel.

All good, first three slots will be Ha, SII and OIII. What would be the recommendation for the other 2 slots? Green and Blue, so I can use Ha, G & B to do LRGB style images with Ha,Ha,G,B?

I just wanna cover as much ground with the one wheel so I don't have to buy another wheel and always have to swap stuff around.

Cheers!!:)

[gbeal]

What size filters?
If 1.25" then consider changing the CFW, I used a Starlight wheel which had 7 slots, making, LRGB, plus the 3 N/B all in the one wheel. Very convenient.
Gary

[TheDecepticon]

Filters are 2 inch and I do not want to increase the weight, I want to work with what I have.

[jase]

Hmmm tough call. I think on the 5 position wheel, I would end up going with;

1. Red
2. Green
3. Blue
4. Ha
5. OIII

You'll have fun in collecting Ha and OIII data. SII will test you as its hard to dig for signal on certain targets. I suspect you'll find it difficult to use narrowband Ha as Red to match broadband green and blue filters. Stellar profiles of narrowband data typically yield a much lower FWHM value than broadband.

You might find it easier to swap out the filter wheel carousel as opposed to replace the filter wheel all together. That way you can have a narrowband and broadband set.

[TheDecepticon]

Thanks Jase, good info. I'll think on it a bit harder.:thumbsup:

[Terry B]

The only problem with these combinations is that you are restricted to only imaging bright Ha containing objects. No lum filter for galaxies etc.
I had a similar problem with using photometry filters and colour filters. I eventually got a bigger filter wheel to solve the problem.

[JohnG]

That is what I ended up doing, changed from the CFW-8a on the ST2000XM to the CFW-10, loaded up the ClearLRGB and Ha (6 and 12Nm) O111 and S11. Makes it all very easy.

Cheers

[Terry B]

Yes. I also bought a CFW-10
my filters are BVRIU Lum GR Ha and a star analyser grating.
I can use the photometry B for colour imaging if I need.

[TheDecepticon]

Thanks guys.

I have a Moonlite focuser with high res stepper which will carry 8 pounds, according to the specs, so a bigger wheel should be ok, just don't have the money for it at the moment, so I'm trying to cover as much ground as possible with what I have already.

Im only using a 110mm scope, so at the moment, I don't do galaxies. When I move to a bigger scope, I might change filter wheels.

:)