My equipment
I'm using the following equipment:
- Meade 8" LX200GPS
- Meade wedge
- Meade balance weigth system
- SBIG ST2000XM with CFW8a filterwheel
- SBIG LRGB filterset
- SBIG AO-7 adaptive optics
- self made lightbox
- Pempro software for periodic error reduction and polar alignment
- Orion dewshield
- Dew zipper
The image on the left shows this setup in my backyard. Since I don't have a permanent setup I take the whole system out during clear nights and place the scope in three self made place holders which are plugged into holes drilled in the pavement. The placeholders are made of stainless steel and I normally leave them outside. In this way I can preserve my polar alignment for one imaging session to the other while still taking all equipement back inside everytime. Checking the polar alignment is done by using Pempro once in a while. Applying this procedure works really well and allows me to setup everything in less than 15 minutes. The placeholders were designed by my father in law and myself and made by a friend. If you have any question about these placeholders just mail me via the contact section.
Another self made and very use full device is the lightbox. This lightbox is used to take flatfields in an easy way with very good quality. See the tutorial section as an example of working with flatfields. The impact of flatfields on your deep sky images is huge. The lightbox is made of polystyrene, plastic glass, some white LED's, a light diffusing sheet, tape and a transformer. The design of the box is by myself,my father created the electrical part by using a transformer of a broken baby phone. If you have any question about this lightbox just mail me via the contact section.
Pempro is used to fine tune the rought polar alignment and most of all it's used to measure the Periodic Error (PE) and program the PE curve into the LX200 resulting in a significant lower PE. The two screenshots show the measured PE before PE correction (left) and after applying 4 correction runs (right). The initial PE of 18,54 arcsec peak to peak was reduced to 6,35 arsec peak to peak by using Pempro.
According to Meade the limiting photographic magnitude of my 8" LX200GPS is about 16.5. I have measured this limiting magnitude using a quick image of M27 I took in July 2008 (see Photogallery). I used the online library of ESO to get a DSS image of the same portion of the sky and make a comparison. My images is shown below at left, the ESO image at rigth. The latter is somewhat grainy, maybe due to the fact that it is provided in a compressed form. I used the photometry feature of TeleAuto to the determine the magnitude of the weakest objects in my image based on known reference stars. The result of this test is that even a single 5 minute exposure under an average Dutch (suburban) sky reveals objects of magnitude 16.4. Close to the mentioned limiting magnitude. I will try this again with real clear skies and longer exposures.
