Improving the guiding during August 2013… and results

Yes, guiding is one of the big challenges of astrophotography, … and more for some of us who cannot afford the great, state-of-the-art, but very expensive, mounts out there.

It’s been some time since I introduced an alignment run every night, as part of my routine. I do so with Pempro, a great utility. Although this step takes valuable time off of my session, it really pays off, as guiding is smoother. As it’s commonly said, the best guiding is the one that isn’t needed at all.

The result of my improvements are two images. The first is M27, the Dumbbell nebula in Vulpecula:

M27 detail

  Go to this object description and this image technical detail.

And the second is part of the Sharpless 2-132 complex in Cepheus:

Sharpless 2-132

  Go to this object description and this image technical detail.

In both sessions, guiding worked pretty well. So well that the declination correction gave way to the RA correction as the main factor. My stars are leaving behing the vertical bloated shape, … only to adopt now a less serious horizontal little elongation  :-)

The M27 image is a composite made with regular RGB filters. As some planetary nebulae, this beauty doesn’t take advantage of the H-alpha filter, unless you shoot using a complete narrowband set. This is due to the main OIII signal, which radiates in the blue-green part of the visible spectrum, being the traditional H-alpha signal weaker.

Processing has focused on getting the most out of the fine detail inside the nebula. It included deconvolution, with custom star mask and a luminance mask to protect both stars and background. A bit of sharpening and shrinking was applied to the main stars.

Bright as it is, this target only needed 1200 seconds of light through each filter, in a moonless, clear and quiet night.

On the other hand, Sharpless 2-132 clearly benefits from the H-alpha filter. Is the kind of nebula made of hidrogen, that radiates from ionization by nearby stars. So I imaged it with this narrowband filter, plus the regular RGB. As always, I built a synthetic R channel, from the normal R and the H-alpha one.