Spectro-newbie question

[Grue]

I am still in the basement -- havent gotten to the ground floor yet, as there is so much to read and understand.

I am thinking about what scope to use/get for Spectro and have the following questions:

1) Does C.A. from an achro scope affect spectrum analysis / processing?  Are APO scopes preferred?

2) Do diffraction spikes, say from an RC scope affect spetrum analysis / processing?

Thanks in advance!

--Rick in NWA

[Merlin66]

I assume you're thinking of starting with a grating?

If so, then yes a good APO gives excellent results, as does a reflector (f5 or so). An achromatic refractor still gives reasonable results but the spectrum image will suffer from "fishtail" where the CA causes some distortions especially down in the blue/ UV...

The spider diffraction spikes don't cause any real problems.

[Grue]

I assume you're thinking of starting with a grating?

If so, then yes a good APO gives excellent results, as does a reflector (f5 or so). An achromatic refractor still gives reasonable results but the spectrum image will suffer from "fishtail" where the CA causes some distortions especially down in the blue/ UV...

The spider diffraction spikes don't cause any real problems.

Yes, indeed I've puchased the Star Analyser 100 and the adapter for some initial spectra with my DSLR.

I thought that a spectra thru the achro would be distorted and harder to identify any absorbsion lines due to the lack of convergence.

I wasn't sure about the spider spikes tho.  I like that term, heh.

Thank you for the response!

--Rick in NWAr