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I’m happy to give it away to a member and even pay carriage out of BAA funds. I’m just trying to establish what interest there is in it.
You should get very good results from your setup Tony. Have a look at FireCapture (which is free) for video capture with the ASI764MC. I don’t know how it compares with SharpCap for this purpose, but I use FireCapture. The exposure required is likely to be in the 0.001s range, but in FireCapture you can assess this using the live histogram. You ensure the camera levels are about 75% filled. Gain should be quite high. You capture a video between 30 and 60s length as an SER file, then align in AutoStakkert! using the ‘surface’ alignment function and a grid of alignment points, then select say the best 50% of frames to stack. You can then sharpen the image in another program, or try the sharpening function in Autostakkert!.
One thing I do which I find is beneficial is to use an IR-pass filter on the camera (either in a nosepiece or a filter wheel) in addition to the objective solar filter. (I don’t have the Seymour, I have Thousand Oaks). This steadies the seeing. The result will be a red image. Other people use the Baader solar continuum filter (which is green). Basically you will always improve the seeing by excluding blue light. You can capture the data in FireCapture in mono (no de-Bayering).
Best of luck.
The answer to the question is that we do not publish them on the website. We used to publish them consistently in the Journal, but this has not been done for the past few years.
I think we should (at least going forwards) publish the reasons for all awards both in the Journal and on the website, but I don’t think we should publish the original citations exactly. They are essentially private documents, intended for committee consumption, and not necessarily written with a view to publication.
If we could get round to summarising, and publishing past citations on the website as well, that would be good. If we do, I’ll make sure we start with Denis’s!
David (President)
I am glad the effort (and expense) we went to in order to live-stream the meeting is appreciated.
This feedback makes me more determined that all future London meetings will be streamed. Those held in other locations may or may not be practical to live-stream, and I doubt we would do it with a multi-day event like Winchester.
The Christmas meeting can now be watched on the BAA YouTube channel.
David (President)
The Takahashi Epsilon 160ED retails now at £3,500. If this is not an ED version it is worth less, and being at least 10 years old obviously reduces the value, but they have a very good reputation, so I’d say if the mirrors are in good condition it should be worth at least £1,500.
Thanks for the review. It sounds fair. It is a common observation that the proofreading of Springer’s astronomy books has been poor to non-existent in recent years. Some of them are good, if they have a careful and dillligent author who writes well. It appears this one is not an example of that.
The Board has been in correspondence with the Galloway Forest Dark Sky Observatory with a view to helping them rebuild.
David
Very interesting Paul.
By the way, I showed your picture of the volcano going off behind your observatory near the end of the Sky Notes in the October meeting.
I hope things have calmed down.
David
Be assured that this idea is still under consideration and nothing has been finally decided, nor any possibility rejected.
We did subsidise members’ access to commercial remote telescopes in the past, for projects approved by Section Directors. The take-up was very low.
Any insistence on ‘research only’ is also likely to lead to very few people using any facility that is set up.
Variable star, cometary/asteroid and planetary research all have rather different hardware and software requirements.
So the whole thing is not straightforward, and, as has been pointed out, there are plenty of risks and pitfalls. But they could possibly be overcome.
In the next few months I wish to gather together ideas such as this, suggested by members, for ways of spending our funds to benefit observers. Ultimately Council will make a choice, and decide which, if any, projects to pursue.
David (President)
See also my article in the Journal, 2019 December
A better title would be something like ‘Optical aberrations: identifying and treating them’.
The word ‘aberration’ in general means something abnormal. So an ‘Aberrations in amateur astronomy’ would mean anything abnormal in amateur astronomy – like someone claiming to speak Venusian.
David
It’s water in the camera. Common problem in the UK: telltale point is pattern changing as the camera cools.
You need to dry the camera out. Putting it in a warm, dry place for some days might suffice, without having to take it apart.
My preventative solution to this is to keep a dew heater round the nose of the camera and switch it on at least 15 minutes prior to imaging. Sometimes I’ve kept the heater on for days to dry the camera fully.
Thank you all for your replies. There are some useful leads there, which I will be able to distil into a (hopefully) useful reply to the original enquirer.
Thanks Jack, I’ll put it in the next E&T News. But I’ll keep it separate from the cats, as it would poison them.
All the images in this set showed the interesting terminator irregularity in the S hemisphere. It is clearest in the first image, R from 02:38, and I have given an enlargement of that one. Comparing with other published images from the same night, I believe this is due to straight N-S ranges of cloud over the Tharsis Montes casting shadows. The irregularity seen here is a combination of a bright line of cloud catching the light, and its shadow preceding, with another high bank of cloud to S just going over the terminator.
Thanks David, that is very helpful. Is your email still the Freeserve one? I’ll get in touch with further details.
Don’t try contacting the first website that Daryl quotes. People who have been involved with BAA for a while will know why.
The bolts that are supplied with the telescope are about 2″ long, smooth-shanked and threaded with a ¼” Whitworth thread in the top ½”.
They work by the thread engaging with the mirror cell while the unthreaded section passes through the hole in the back of the scope and the knob clamps tight. Owing the varying mirror position at different focus points, I am not sure if they would succeed in in locking the mirror at any point in its focus range, or not.
Assuming they do, and assuming you are using one optical configuration with camera at a fixed distance out in a Crayford or similar focuser, I don’t see why you should not lock the mirror in position with these screws after you have established the approximate focus point for the mirror, with the Crayford in the middle of its range, to give a bit of temperature compensation around that point. However, I have not tried this. I tend to do my critical work around the same part of the sky, the meridian, so the collimation does not change much.
