When I bought my first Telescope in 2011 I also bought a BAADER O III filter(10nm) and Light Polution Filter. I had never tried out the O III filter until a few nights ago. The moon was full so I would typical avoid deep sky objects. I decide to try the O III filter because it is a narrowband filter. I decided to image the Crescent Nebula with my 8″ EdgeHD scope at F10 (2032mm FL). I had previously imaged this nebula a few weeks ago using my OPTOLONG L-eNhance…
Category: CaLIGHTs
Issues or posts specific to CaLIGHTs Astronomy LIGHT frame calibration Tool
CaLIGHTs Version 3.1.7.00 released
Release Notes Latest Revision 3.1.7.00Image Preview You can now use the PgUp and PgDn buttons to switch back and forth between image previews. Image Preview I have added a new feature called Shift HFD Rnd Angle. This feature performs analysis of your displayed LIGHT frame. It will make a copy of your LIGHT frame and then analyze the stars in your LIGHT frame. The results of the analysis are used to modify the copy of your LIGHT frame and also to display the results in the title of the image.…
Star Eccentricity and Guiding Accuracy
The Pix Insight documentation specifies that most people would consider a star to be round when the Star Eccentricity is less than 0.42. The equation for Star Eccentricity is a bit convoluted but a star eccentricity 0f 0.42 is also equivalent to a Star Aspect Ratio of 0.91 or a Star Flatness of 0.10. I have chosen to have CaLIGHTs calculate what I call Star Roundness(%) which equals the Star Aspect Ratio multiplied by 100. So a CaLIGHTs Roundness value of 91% equals a Pix Insight Star Eccentricity of 0.42.…
Narrowband Color Shift in my Astrophotos
Revised Feb 5th, 2022 Recently I noticed that, in my narrowband astrophotos, the red color of the stars in my calibrated LIGHT frames seems shifted a few pixels. The blue pixels are also shifted but by a much smaller amount. I decided to invent a visualization tool for CaLIGHTs that makes it easy to study this color shift. In CaLIGHTs V3.1.6 I introduced a feature called SatGuard. This feature requires CaLIGHTs to be able to identify bright stars and determine what pixels need to be modified. I had already created…
My LIGHT Table Solution
In 2021 I bought a LIGHT Table on Amazon which I believe works very well. It also caused me to develop a method for taking FLATs that is quick, accurate and easy. Background A key aspect of Astrophotography is taking quality FLATs. Vignetting caused by lens or telescopes is not simple. Even though your telescope, focuser, filters and camera all look like they are perfectly aligned…they typically are not. The center of your LIGHT frames is not always the location where the vignetting is at it’s minimum. This “sweet spot”…