Using digital finder charts at the eyepiece


Three times a year I leave the rainy, lightpolluted Netherlands to observe under dark skies in France. This summer (2010) I even went to Spain, to visit RETA, a starparty in Aras de los Olmos. Before leaving for an observing period, I used to print many finder charts, put them in plastic folders and ring binders. And besides that I had to take observing guides to the observing site. But all that belongs to the past from now on. I bought an e-book reader with more then enough capacity to contain all charts and guides I need at the eyepiece (I did *not* copy the books shown in the photograph above). In the photograph above you can see what I mean: to the left the ring binders and books (sometimes I take even more), to the left the e-book reader (Entourage Edge). Actually, this is more then an e-book reader. The left screen is an e-book reader, the right one is a 'tablet' I use mostly for email and internet.

The e-book reader part of the 'Edge' has no illumination and the other screen can be shut down, making it possible to read the charts, etc., with a faint red light, just like I used to when using printed charts. It's even better than printed charts, because of the zoom function of the reader.

The photograph above shows the whole 'Edge', with its two screens. It is easy to fold the screens 'back-to-back', making it even smaller. The e-book screen measures 9.7 inches diagonally, large enough to be able to read the charts comfortably.
The photograph above is a close-up of the e-book reader screen, showing a finder chart for Arp 73. Using the small arrows below the chart it's possible to proceed to the next/last page or go back to the former/first page of the file. The # brings up a small window, in which one can enter the page one wants to go to. The first page of the file is an index page, from where I can go to every page I like. The order of the finder charts matches the order of the objects in the laptop of my 'Bartels driven' 20 incher. So the only actions I have to take when I am ready for the next object is pushing a handpad button to let the scope slew to another object and press the forward arrow to let the reader do the same.

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Email to: Jan van Gastel