View Full Version : Sh2-157 in HST palette

2012-Sep-09, 09:25 AM
Hi All
I've been working on this for the last few weeks in between work and weather, it is of Sh2-157 (also known as the lobster claw nebula), I managed to get 12x30 minutes Ha, 14x30 minutes OIII and 9x30 minutes SII (would have got more SII but the whole sky misted up in the space of five minutes, reminiscent of the film "The Fog"). These were then colour combined according to the wavelength ordered palette so SII:Ha:OIII = R:G:B.
It was taken with a FSQ106ED at f5, FLI ML8300 on a Paramount ME using a lodestar to autoguide with dithering. Processing consists of levels, curves, colour balancing and contrast adjustments.
The Ha and Ha/OIII versions can be seen in the image gallery on my website http://www.imagingtheheavens.co.uk along with a much wider field version
Below is a link to the full size version
Thanks for looking
Best wishes


2012-Sep-09, 09:26 PM
Looks good. SII seems stronger than in many nebulae.

You used to use a TMB 115 and several different Starlight Xpress cameras. Now its the FSQ and 8300 chip camera. How do you like the change? I've heard the FSQ is hard to keep in focus when the temperature changes. Any issues there? My LX200R is a nasty with rapid temperature drop here. I need to think about wide field though I can't seem to begin to cover the narrow field stuff on my to-do list.


2012-Sep-10, 07:49 AM
Hi Rick
Thanks for the comments, the FSQ106ED and ML8300 is a fantastic combination and I will be adding a ML16803 to it next year. As you mention the focus changes with temperature variations are a nuisance especially with a smaller CFZ, but I have found that I've only ever needed to change focus once during the night (this is in addition to checking focus after meridian flips and when changing filter, although I generally only ever shoot one filter in an evening)
Best wishes