This is an image which I gathered data on in 2017 along with my friend Dean. The Bat nebula and Ou4 have been imaged many many times by nearly everyone. This is our attempt. We used 2 scopes from three different locations and collected Ha and OIII data. The first set of data was from my backyard with a Stellarvue SV70T and QSI 583 camera. The second set came from the Okie Tex Star Party where both of us collected data during the week. One set from my SV70T and QSI 583 and the second set from Dean's Tak FS60C and a QSI 640. Lastly we both continued to collect data from our homes until Nov 2017. I originally uploaded the processed image to my website (http://www.starscapeimaging.com/page212/index.html) back in 2017.



Recently with the new Normalize,Scale,Gradient script in PixInsight I reprocessed the image. A shout out to Adam Block's video's about the NSG script. If you have access to his tutorials, check these out. This image is the result of that rehash of the data this month.

Text from my original posting on my website: This image of the Flying Bat nebula and the squid nebula was undoubtedly the hardest image I’ve tried to process. The image was taken in three steps, at home, the Okie Tex Star Party in Kenton OK in Sep and my friend Dean's home in Ky using two scopes. I started taking a few Ha exposures at home before I left for the Okie Tex star party using the Stellarvue SV70 and continued imaging using the SV70 at Okie Tex. My friend Dean also imaged this object and provide me a bunch of Ha and OIII exposures with his Tak FS60 and all were combined into this composite image using PixInsight. The squid nebula, Ou 4, is extremely faint and is shown here at close to its relative brightness. It looks like a ghostly blue green transparent aberration. It was only recently discovered in 2011 by French astro imager Nicholas Outters and has a elongated bipolar shape. It’s virtually invisible in normal RGB or Ha exposures and only faintly visible using a OIII filter. This image combines 12.3 hrs of Ha and 24hrs of OIII exposures. The image scale is 5.98 arcsec/pixel.

A somewhat new processing flow was tried. Below is a summary of the steps for those interested. I also tried to keep Ou4 a bit ghostly as it is.

I know there has been a lot of concern/criticism and healthy discussion about Topaz De Noise AI. Rightly so, as it can be used in a way to create something from nothing. Added detail can be a problem when using too much sharpening. One has to be very careful about any application of sharpening at this step. The key, turn sharpening off or down to 1. Also, don't do it on images with stars. So, I used Topaz on this image with little to no sharpening. I blinked the before and after many times to see if and where anything was added. I couldn't find it but it did do a great job getting rid of the noise, similar to the several tools in PixInsight applied the right way. So, I'll let you judge for yourselves.

Processing steps : This image was processed with PixInsight. Topaz De Noise AI was used as an intermediate step to de noise a starless image.

The subframes were reduced and cosmetically corrected using the Batch preprocessing script of PixInsight. Registration was done using the Image registration tool.

The registered images were run through the Normalize, Scale, Gradient (NSG) script in PixInsight to correctly account for the different sky conditions, scopes and camera's

The master Ha and OIII images were created using the PixInsight image integration tool.

The masters were gradient corrected using dynamic background extraction

The linear Starnet script was used to create starless versions of the Ha and OIII masters and the script was also used to create a star mask using the Ha image.

The starless Ha and OII images were combined into a HOO color image and the normal Ha and OIII images with stars were also combined into a HOO image.

The background neutralization tool was used to color correct the backgrounds of both images

Both HOO images were noise rejected using TGV De Noise in the linear state

Both HOO images were stretched using the histogram tool.

The starless HOO image was saved as a tiff and opened in Topaz Labs De Noise AI and noise rejection was applied at level 4 and the image was blinked and inspected to make sure no spurious details were added.

The starless HOO image was brought back into PixInsight and the star mask made earlier applied to the starless image. Pixel math was then used to write the HOO image with stars to the starless image transferring the stars to the De Noised starless image

Several iterations of curves were applied enhance the nebula

Adam Blocks star de emphasis technique was used to tone down the multitude of medium to small stars giving more visibility to the nebula.

Several more iterations of curves and color saturation were applied to various parts of the image and the image was saved as a jpeg.