Forum Replies Created
-
Posts
-
The C11 on its own, assuming it is not damaged in any way, will sell easily for £1000. You could ask for £1500 but I don’t think it would sell. Part of the issue is that not many people can take a scope of that size, of if they can they may want the HD version.
What is the motorised focusser?
No idea about the Tak.
There is a second-hand copy on Amazon.co.uk for £48.50 – they might deliver to the USA.
https://www.amazon.co.uk/dp/3540199802/ref=olp_aod_early_redir?_encoding=UTF8&aod=1
Alan,
I got a copy of this book maybe a year or two ago as part of a job lot of books. I flicked through it at the time and saw some equations and complicated graphs and decided it was too advanced for me, so I stuck it on a shelf… I’ve now looked in it in more detail on your advice and it is a remarkably accessible book. Yes there are equations and in places, it goes off on another level, but there is a good proportion of the book which is very helpful and informative. Thank you for making me get it off the shelf.
James
Thanks all for the replies. Some very useful additions to my list.
I’m planning to keep it simple (like me) and concentrate on the errors and aberrations which are common and [relatively] easy to resolve. I’ll get someone to talk about star testing to make people aware of the more advanced methods of testing optics available.
Thanks.
James
Here are the answers to the quiz:
https://hidrive.ionos.com/lnk/VZUDuoge
We discussed the answers and the other options in our online meeting on Thursday which can be watched on YouTube:
https://www.youtube.com/watch?v=5Ck0jXq_uuk&t=3178s
We’ve since learnt at least one of the questions has an error; there is a Mare Australe on Mars as well as on the Moon. The number of principal stars in the asterism of Cepheus is also being debated… 48 unambiguous questions out of 50 isn’t bad I don’t think!
James
Can you post a picture of the bit which is stuck?
Have you used this site to help you:
http://www.astro-baby.com/EQ6%20rebuild%20guide/EQ6%20RA%20strip%20down.htm
James
David, we can probably help out. We’d need to test the data transfer rate from our observatory over 4G else could set up a 14” or 11” SCT from someone‘s garden.
JamesThis is going to be a tricky one. We’d planned to try and observe the occultations of Venus, but I was undecided what filters to use, and I need to make a longer sun-shield.
James
Taken at 01:34 UT 30.05.2020 with Canon 6D at prime focus on Celestron C11 (15 second exposure, ISO 800); excuse the hot pixels; a cropped version with brightness stretched to show it easier. Have the raw files.
 30.05.2020(BAA).png)
 30.05.2020(BAA)stretched.png)
Gary / Jeremy, I’ve never made a meaningful observation of anything the VSS is interested in. What sort of settings would you recommend For a DSLR at prime focus? I think the FoV will be too wide with my 80mm refractor so May have to jump right up and use my C11 and Canon 6D. I think I can get to a site with a low northerly horizon that isn’t too light polluted; but 3am though, whose idea was that?!?!?! 🙂
Thanks for all the comments and links. It is fascinating. I’m not intending to image or observe near the Sun, I was just interested to see what sort of results the serious amateur can achieve so close to the Sun. Some of the images in the article Alex links to look far too close for comfort!
Thanks.
James
Chris, that is really impressive, thank you. Looking at those dates/times on Stellarium, it is really impressive at how close to the Sun 6 degrees is. Do you take any measures to extend a dew shield of the like to reduce the glare of the Sun into the optics?
James
Yes, with fewer aircraft and fewer cars around, the sky conditions may improve.
With regards air “quality”, I’ve been watching the UK Air Information Resource and not seen any particular downward trends yet. The data below is for the last 7 days for Canterbury, but back data for several years from numerous sites around the country exist:
https://uk-air.defra.gov.uk/data-plot?site_id=CANT&days=7
James
There are typos in the booklet too unfortunately:
https://shop.royalmail.com/visions-of-the-universe-prestige-stamp-book
There are a few, some:
The Cambridge Star Atlas (2011), copies available for under £10.
Uranometria 2000 volume 1 (1987), copies available for £25.
Sky Atlas 2000.0 (1985), cheapest seems to be about £40 but it is lovely.
Star Atlas of Reference Stars and Non-stellar Objects (1969), copies £50.
Interstellarum Deep Sky Atlas: Desk Edition (2014), copies £65 or so.
Millennium Star Atlas 3 Volume Boxed Set (2006), £600 or so…
The first two are fine; you can probably find a way to look at them all inside online somewhere. I really do like Stellarium though which is usually my first port of call, with all the added star databases loaded in.
