Helix NGC7293 done last nite ..Saturday.. using two Lumicon Minus-Violet filters , one was a 2in. and the other was a 72mm filter attached to a TeleVue .8XReducer/Flattener thru a 152mm A+M Refractor . I was trying to see if the Minus-Violet filters would suppress the 373nm Sky Glow . The first image was 555secISO1600 and it was a yellow-white over-bright .. so I then did a 195secISO1600 and that was easier to see the Helix and I did seventeen of them . In Canon Digital Photo Professional V4 I got them all to show the Helix and then I made them 16BIT TIFFs and put them into "ImagesPLus" and 'stacked' all eighteen images with SigmaClipAverage tdDev 2.45 . It took awhile to get the haze that was trying to get into the reddish eyebrow part out of the image .. and here is the result . I don't know which images show the reddish area outside of the main Helix but all together they seem to show it a little bit . The Moon was rising for the second half of the exposures and light was entering the images .x I did a Two Star Align with Enif and Marfak and both have small stars in the image to 'Live View' focus on like I did with Enif and then to the Helix .x I have a Baader 7nm Hydrogen Alpha filter and it was oily and wouldn't cleanup until I used a Zeiss Lens Cleaner packet from Walmart and clean cottonballs to clean off the moisture and the oily smear stain was removed ... otherwise I couldn't get it clean .x
