Aart's Blog

Because the 26mm eyepiece does not fit in the Meade basic camera adapter, and the 9.7mm eyepiece has too much light loss in my modest Meade ETX-90EC, I purchased a 15mm eyepiece. This eyepiece fits comfortably in the adapter. Less magnification than the 9.7mm eyepiece, of course, but therefore also less light loss. Below already a quick result (taken at dawn) together with two pictures from the September 7 posting (taken during the day) for comparison. The slight curvature in the picture is a bit worrisome, still have to look more into that. Can't wait though to try some real astrophotography with the new eyepiece. prime focus (rear port) 9.7mm eyepiece projection (adapter) 15mm eyepiece projection (adapter)

Since the moon is back at a normal hour, I could do some more experiments with astrophotography. Below a comparison between prime focus and 9.7mm eyepiece projection photograph of the moon using an Meade ETX-90EC. Disappointing result for the latter, since a digital zoom on the prime focus photo is much more clear.

If you are following me on Facebook or Google+, you probably noticed that lately I have been less busy with chess programming . Instead I have been spending  free time at my Meade ETX-90EC telescope getting familiar with astrophotography . Here are some of my first pictures using prime focus configuration (single shot manual exposure, using mirror lockup and remote control to minimize vibrations).  I really like the clarity of the moon picture and was happy seeing the ring of Saturn so clearly. I also tried eyepiece projection configuration , but found this extremely challenging. Due to the inherent light loss at higher magnifications, it is very hard to find and focus the object (hints from experienced astrophotographers welcome!). Today I have been experimenting with the different configurations during daytime. Below you see some sample pictures of my neighbors house number sign, taken with the camera's 300mm telelens for reference and three ETX configurations (n

More engines were added to the Chessbase compatible engines for Android package . Many thanks to the engine authors for their explicit permission.

I am about to release a next version of Chess for Android that recognizes engines in the Chessbase compatible format discussed in the previous blog posting. The new version is available as direct download or from Google Play . With this release, all engines installed in this format (either the engines that ship with the Chessbase for Android application itself, or engines installed in this format, such as my own Engines.apk package) are available for direct import in Chess for Android as well as in the latest Chessbase for Android . Together with sharing capabilities, this greatly enhances the 'chess ecosystem' on Android, since chess GUIs can now be used interchangeably in a much simpler manner. As before, engines authors that want to be included in the package can drop me an email.