View Full Version : M31 with Televue/FLI prototype imaging system

2013-Sep-10, 08:02 PM
As the moon wasn't present I thought I'd have a go at some LRGB and I was able to complete M31 in three nights with some cloud interruption in between. M31 just about clears the roof of my house so I am able to image it as soon as it gets dark. This was taken with the Televue/FLI prototype imaging system that I am testing at the moment which consists of a NP127is (without the mechanical manual focuser), a custom built spacer tube with built in adjustable tilt and focusable field flattener, this is attached via zero tilt adapters to an Atlas focuser, Centerline filter wheel and Pl16803 camera. (details on the system can be seen on my previous post of the veil nebula).
Exposure times were
26x10 minutes Luminance
12x10 minutes Red
8x10 minutes Green
11x10 minutes Blue
Auto guiding was by a Officina Stellare Falco guide scope and SX Lodestar with dithering.
The system is proving to be very easy to use and the focus is very stable with only one adjustment necessary during the night.
Due to light pollution there were varying gradients on the different master frames so I dealt with the gradients before colour combining.
I am particularly pleased with the result as I've managed to pull some detail out of the dust lanes in M110 which can be seen better in the full size version at the following link
Depending on time and weather I may add some Ha to this but I have heard varying tales as to whether it is worth it with this subject.
When I've a bit more time I will post some pictures of the system on my website
Thanks for looking
Best wishes


2013-Sep-11, 06:47 PM
What a picture!

What exactly are you recording in the luminance exposures?

2013-Sep-12, 08:24 AM
With luminance you are basically recording unfiltered data in monochrome so the luminance channel has the main detail. A luminance filter is basically a clear filter with infra red block. Some people in heavily light polluted areas sometimes use a CLS or IDA filter in place of the luminance but I just use the luminance
Best wishes

What a picture!

What exactly are you recording in the luminance exposures?

2013-Sep-13, 08:38 AM

2013-Sep-14, 02:38 AM
Nicely done!