M57 30 sec. image taken using C5 f/10 ZWO ASI178MM with StarAnalyzer 100. Original was 16 bit png, 3096x2080 pixels. resolution was 3.7 angstroms/pixel.
This is a grating only low resolution spectral image (no slit used).
This is fascinating! My first thought was that you would just get a wide smear. The slitless system really only works with point sources. Anything wider gets smeared out and the single wavelength is as wide as the original image.
What we are seeing though is two relatively clean versions of the original ring.
I strongly suspect that you will find that those two images are centered at 501 nm and 656 nm.
You have just measured the emission bands of HA and OIII. Way to science!
Image META information
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What we are seeing though is two relatively clean versions of the original ring.
I strongly suspect that you will find that those two images are centered at 501 nm and 656 nm.
You have just measured the emission bands of HA and OIII. Way to science!