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I’ve had a useful email conversation with a technical person at Lunt. This is a summary of their suggestions which I have yet to try asI’ve not had time nor a clear day! It has a new blue filter in which I replcaed before the April 2024 total solar eclipse.
Now, may I ask with the double stack removed, do you also experience such views? It is certainly true that a double stack can really make your image extra special but if not tuned correctly, can also consistently be at odds with the primary etalon.
What I might recommend here, might seem like a step backwards. When I test double stack units, for the LS50THa or otherwise, I of course start with my scope in single stack mode. I tune and adjust until I am at the best point, and then I introduce the double stack. From there, I make sure my double stack is at rest (that is, no tilt introduced through the tuning wheel) and begin to tune from there. There are times when double stacks need a little something else. If I was testing your LS50THa, with this LS50c, the first thing I might do is go through the entire range on the LS50c that is attached and find my absolute best view while tuning that (after having tuned the primary without the double stack attached). If my field is much like your picture, my next thing I do, is to attempt to retune the primary etalon. At times, a little adjustment on the primary can really go a long way to making the double stack image what I would like it to be. From there, I would lastly try rotation of the double stack unit itself. This may seem the most precarious, but of course you have multiple threads securing it, and you wont need to during any more rotation than the initial 360 degrees, as anything past the first complete turn will put you at the same physical position in terms of lens tilt, but with just less thread to hold the filter onto the telescope.
Very often, customers who are experiencing a lack in quality views with their double stacks will find some relief between these suggestions.
Lastly, I am uncertain how old your telescope may be- but have you checked the BG (Blue glass) optic in your blocking filter as of late? This would be the blue glass element found under the nose tube that is introduced into your focuser. It should be perfectly clear, and without occlusion. Some of our older scopes have an uncoated version of the BG, while the new ones have a coated version. In either case, it should be 100% clear.
Thanks both.
The Lunt website talks about the issue, but gives conflicting advice on a solution. At one point says the B600 is fine for imaging with the 50mm Lunt, but then in the next paragraph suggests one should go to the next blocking filter up for imaging. I’ll email them, as they have been helpful in the past. It also sounds like tilt may be an issue, so something else to explore and MUCH cheaper to rectify!
Thanks.
James
Yes, another one of that era gone. Sad indeed.
I never met Storm but we had emailed, mostly me picking his brains about things from the past, and he was always helpful, even when the topic related to Patrick Moore! I don’t know the full story of the bust up in the BAA with Storm and Patrick and others apart from what I’ve read in Martin Mobberley’s books.
Storm’s knowledge of weather phenonomena was amazing and I’ve got several of hie weather books. We most recently corresponded about Cecilia Botley who like Storm was also interested in the weather. I had emailed him last week about a book he had translated (Atlas of Great Comets by Ronald Stoyan) saying what a great book it is and would he pass my thanks onto the author. I never recieved a reply.
I look forward to reading more about his life as and when someone writes a biographical article about him.
James Dawson
Thanks for all the comments.
I will download Astro surface and have a play with that but in the meantime I’ll stick with AS!4 and Wavesharp which both appear to process very quickly and seem to use all available processing power.
James
Looking at this again on my desktop PC (rather than my laptop), I think the bottleneck is the software. Registax only seems to use one or two cores of the CPU and then the utilisation of these appears to be about 50%, whereas if I use Autostakkert it uses all cores and utilisation for each goes up to near 100%. This is despite altering Registax to use “8 CPUs” in its settings (this PC has 12 cores). I just need to now teach myself how to properly use Autostakkert and just use Registax for wavelets though their Wavesharp software seems much better at this.
James
Thanks Grant.
Windows 11, 32 GB RAM, nothing else major running. Task manager doesn’t suggest the bottleneck is CPU, RAM, GPU, disk, WiFi… so I wonder what is the limiting factor which causes software to not run quicker?
In fact, I’ve got several on Amazon too if anyone is interested; most have been given to the Society for the History of Astronomy and they just need to go to good homes.
Jack there is a video of a chap making adjustmetns to one of these mounts, and also a thread on cloudy nights describing adjustment of the slop in the system, these may help you:
https://www.youtube.com/watch?v=zvf8SJiXZOg
https://www.cloudynights.com/topic/382939-vixen-porta-mount-repair/
James
Bill if this meets your requirements in terms of capacity and connections, then it looks good; it seems to be £20 cheaper on Amazon. The others out there seem to be significantly bigger and heavier.
Bill there are countless options out there. As Jeremy says, you need to work out how much power you need between recharges and go from there. Much more expensive than lead acid though, and still needs to be looked after and recharged appropraitely and regularly. There is nothing wrong with lead acid batteries, though twice the weight of lithium, as long as you take care of them.
Thanks Paul. If the solar panel is on the dome, that makes sense. I’ll discuss the idea with the others. Thank you.
Mel, thanks. We want something which will hold it whenever someone takes their hand off the crank handle; if they let go it runs away as described above. The U bolt idea is good though for holding it; we use a rope at present which does something similar. But thank you.
Paul, that is a good idea. Our shutter is pretty heavy so it may need to be a chunky battery. How do you go about charging up that battery? We’d need someone to remember to connect it to the charging circuit unless we always parked the dome in azimuth in the same position and set up a positive and negative contacts at specific locations on the dome and the on the rim of the supporting wall. But an interesting idea.
James
I think it would be too slow Bill unless we motorised it but getting power to the dome at any position in its 360 degree rotation would be difficult.
And posted this on SLG: https://stargazerslounge.com/topic/427185-ratchet-mechanism-for-opening-slit-in-dome/
Alex, thanks for this. The image you have created is much more akin to what I was hoping to get. You’ve managed to bring out the tail in lots more detail and there is structure visible within it, without blowing out the nucleus. I can still still the impact poor flats are having on the data, but I am really impressed. I’ve made an animated gif to show the image you could get out of my data vs the image I got out. Given it is the same data, I think there is something you are doing in the stacking process and in the post-processing step which I am not doing. Maybe sometime I can watch what you do and learn from that. I am so grateful for your time.
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Thanks both. My flat panel is an illuminated artists sketch pad from Amazon; I wonder if I should have just made the pad brighter so that I could have reduced the exposure length which may have avoided the flickering. I’ll experiment.
The DSLR doesn’t use counts so I used the histogram and aim for a range between 25-50% and take 5 or so at each setting to later review on the PC and use – I only use one exposure batch, not flats from different exposure settings.
Thanks again.
James
I suspect no one definitively knows. You may have to conduct experiments with an existing solar farm.
I suspect day time seeing could be impaired as thermals rise off it.
The panels and metal frame structure will release heat quite quickly in the winter I suspect, but large areas of concrete, tarmac, buildings etc will release their heat more slowly which could impair seeing conditions.
Security lighting at night could also be problematic.
