tornado33
10-03-2006, 12:46 PM
Hi all
Here is an image of Eta Carina, taken with my modded 350D, and Baader 7Nm Hydrogen Alpha filter.
2x15 mins ISO 200. After dark subtraction and stacking I opened it in Photoshop and discarded the blue and green channels, only keeping the red channel (as thats all the filter passed).
It seemed odd using this filter as it is so dark nothing at all is visible in the viewfinder, and even Sirius is barely visible as the dimmest red dots. I focussed on Sirius, then moved to Eta carina and did a few short test images to gauge focus and also framing of the nebula.
My off axis guider has a pick off prisim outside the actual focuser tube so gets clear unfiltered starlight to guide with.
Scott
Here is an image of Eta Carina, taken with my modded 350D, and Baader 7Nm Hydrogen Alpha filter.
2x15 mins ISO 200. After dark subtraction and stacking I opened it in Photoshop and discarded the blue and green channels, only keeping the red channel (as thats all the filter passed).
It seemed odd using this filter as it is so dark nothing at all is visible in the viewfinder, and even Sirius is barely visible as the dimmest red dots. I focussed on Sirius, then moved to Eta carina and did a few short test images to gauge focus and also framing of the nebula.
My off axis guider has a pick off prisim outside the actual focuser tube so gets clear unfiltered starlight to guide with.
Scott