Archive for the “mini-WASP Array” Category
The creation and use of the New Forest Observatory mini-WASP array
Although I cannot use the Altair finder as a guidescope as intended, I can still bolt it onto the top of the array with the video camera. I can then use this for the occasional polar alignment check, or to take the odd wide field video clip as/when required. Picture to follow.
Well although I was clouded out last night I still managed to image asteroid 2012 DA14 through the thinnest part of the cloud A single solitary one-minute exposure as the asteroid was moving through Draco at 22:51. The planetarium screen shot shows the region of Draco with three stars arrowed – these are the corresponding three stars arrowed in the mini-WASP image. Nothing to shout about, but at least I got a record of the thing – and it was a huge bonus when I thought I’d got nothing.
There is a large circular emission nebula in the head of Orion centred on Meissa. This huge H-alpha region lies just above Betelgeuse and Bellatrix and actually spans the region between those two stars – so this is a huge emission nebula, although it is also very faint. This image is centred on the star Meissa and although it is composed of 8 x 20-minute subs using all 3 cameras on the mini-WASP array – the emission nebulosity is barely visible. I do remember the difficulty in dragging out faint nebulosity with the Sky 90/M25C combo so this was not unexpected. I need to move the H-alpha filter in place on the Sky 90 and see if I can pick up more of the nebula. This will be next outing if the skies ever clear.
This is the Carbon star 4-Omicron 1 Orionis which lies close to Aldebaran in the constellation Orion. SAO94176 has a magnitude of 4.71 and so is naked eye from a reasonably dark site.
This is a mini-WASP array image using 11 x 5-minute subs from all 3 cameras.
Feb 10 2013
I fitted an Orion finder/guider scope to the top plate of the mini-WASP array today. Well it was raining and I had nothing better to do. However there is a purpose in the madness. I will simply swap the guide camera over from the Megrez guide scope (leaving the Megrez in place) and see if I can get decent guiding with the Orion guider – if I do get decent guiding then I can think about moving on to step 2. Before step 2 however, I should mention something about my Orion guide scope. If I turned the scope through 180 degrees in a vertical direction – something rattled – clearly not good! Tracked it down to the front lens actually moving in the cell as the tube did not push up against the lens to hold it in place!! Would not have made a very good guide scope with the lens moving as I panned across the sky. Easily sorted – I made a “washer” out of a short piece of thin electrical wire – this was sufficiently thick to hold the lens in place against the finder tube. O.K. so next step was to drill and tap a couple of holes in the top plate to take the dovetail holder for the Orion guider. This was not without incident and led to a broken tap and a broken screw Never mind – carry on. Managed to fit the Orion guider firmly to the top plate and I’ll check to see if I can get it working next outing. However, if it does work, it cannot stay fixed on the top plate as the whole array is then too big to fit the dome aperture. I will need to “undersling” the guide scope from a cantilever fitted to the top plate so the guide scope sits between the top pair of mini-WASP imaging scopes. The Megrez 80 guide scope will be removed and replaced by a TS 80mm triplet APO imaging scope. The vacant TS 80 position will be taken up by my second (now fully collimated) Sky 90/filter-wheel/M26C/Robofocus. All I will be missing will be a 4th M26C and Robofocus for the TS 80 – all in good time. And at that point – that will be it – I won’t be able to add anything else to the mini-WASP framework so that will be its final incarnation. The configuration will be the 2 x Sky 90s in landscape mode, both imaging the same FOV. The 2 x TS 80s will be in portrait mode with their FOVs overlapping (mosaic) so that they cover the FOV of the Sky 90s. Hopefully that will then be the end of any further changes/modifications to this project which has driven me up the wall!!
All I wanted to do was drill and tap 4 holes in the top plate of the mini-WASP array to take a dovetail fitting that will hold an Orion finder/guider scope. 4 holes drilled, three tapped when the tap broke in the 4th hole – never managed to do that before. Got the tap out – no bother, it was most of the way through, so I’ll just put an M4 screw in and finish the job off. Turned the head completely off the screw with virtually no force – never done that before either. Just as well it will do fine with three screws, I’ll drill the broken screw out another year
Got a few clear hours a couple of nights ago and set up the mini-WASP array on the Meissa nebulosity – all 3 cameras/scopes up and running for this one Got 8 x 20-minutes of RGB on each camera, so although I only imaged for 160 minutes I actually managed to grab 8 hours worth of data. Now that’s what this project has been all about