Month: May 2020

Back in May of 2005, 15 years ago, I got my first astronomy specific camera: the Starlight Xpress SXV-M8C one-shot color camera. Prior to that I was using my Canon 40D DSLR for astro photos. The 40D was a good camera in general, but too grainy for the long exposures needed for astrophography.

One-shot color cameras like the M8C include the Bayer color filter matrix over the sensor, just like regular photography cameras do. The good part of that is that a every exposure is a color image. The bad part is that the built-in color filters reduce the camera's sensitivity and require longer exposures than a monochrome camera does.

I took this 2-hour exposure time photo of Galaxy M81 with the M8C a couple of nights ago to honor it's 15 year anniversary. It can still produce a nice image!

Early predictions for Comet SWAN (C/2020 F8) suggested that it could brighten to naked eye visibility and be a showpiece object. However, early comet predictions are often overly optimistic.

As feared, it hasn't brightened as hoped. But there's another problem that impacts me taking a picture of it. The comet is staying low on the eastern horizon as it travels northward. The way my observatory is positioned, its roof blocked visibility of SWAN until it was above 9 degrees of elevation. By then the sky had already started its dawn brightening. That means the sky is masking the dimmer parts of the comet's tail.

To get an image while SWAN is still in a darker part of the sky I'd have to move outside of the observatory, maybe on the driveway where there's a better view of the low NE sky, and use my small portable telescope mount.

Maybe... we'll see.

Update on Comet Swan

On May 18th I did take another picture of Comet SWAN. Unfortunately there were cloud layers on the eastern horizon that blocked the comet most of the time. Just as the sky started to brighten, SWAN went between two cloud layers and I got a picture of it just seven degrees above the horizon. Go to the Solar System astrophoto page to see it. The comet was still small though, so it just didn't blossom as hoped.

The roof controller Peter and I are designing for our observatories is continuing to evolve. Peter has it installed and working in his observatory!

A current sensor has been added to the hardware so that the system can monitor the roof's motor current draw and auto-stop on either an under or over current event. A real time clock (RTC) and a SD Card interface was also added to allow status logging.

Roof control and status monitoring is via a web page interface. This page will continue to evolve as new features are added. An example screenshot is shown below.