First Attempt at Remote Imaging.

Another long gap since I've done any imaging but in this time, I've been working on my Wheelie Bin Observatory so that I can sit in the comfort of my house while trying to image. To achieve this, I've connected my desktop (in the house) and laptop (in the obsy) to dLAN adaptors which give me a network over the mains wiring. I use RealVNC remote desktop software to control the webcam software, the electric focuser and the slewing of the telescope (via Cartes du Ciel). The webcam output refreshes on the desktop screen about once a second making it difficult to achieve a good focus.

During this first attempt at remote imaging, the seeing was abysmal and I was plagued with cloud drifting across the field of view. Between the bad seeing, the cloud at times and the slow refresh rate of the webcam output it was almost impossible to get a decent focus. In my haste to get started, I'm pretty sure now that I left the webcam on autoexposure so the exposure changed from one pane of the mosaic to the next. Not a good idea but Microsoft ICE which I used to create the final mosaic made a sterling attempt to balance the exposure from frame to frame.

 Each pane of the mosaic was produced from a 60 second .avi file at 15fps, 900 images in total. I didn't mean to capture at 15fps and couldn't understand why I was unable to change to 10fps but I think now that it was due to the autoexposure being left on. The images were aligned and stacked with Registax5 using an iterative process which creates an image from a small number of frames, realigns the images to create a better image and then realigns with that image until the final image is obtained. This image is then sharpened using a sparing amount of wavelets in Registax before all the images are processed with MS ICE to make the final mosaic.

 

Two small versions of the final mosaic, one with labels to the major features.

 

This is not quite full size so that it will fit on the screen. Quite a few errors can be seen where MS ICE had to cope with poor coverage of the terminator so joins can be seen and adjusting for poor exposure matching led to the sky being too light at the south end of the image.

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