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Great.
I gave a similar, though much less detailed talk to my local society a few years ago, I would loved to have been able to listen to your talk in advance of that to help me prepare. Sandra is always very helpful though so I picked her brains for ideas and images.
Thanks for sharing. Great stuff.
James
I got hold of a Sunagot Delus Slide Duplicator second hand online. It looks like it was made in the 1970s or 1980s, so pre-digital cameras, so a bit confused what it was designed for.
Anyway, it works a treat on my Canon 6D. It is not easy to fit the full image of the slide onto the sensor even when the zoon is set to 1x (the minimum). I tried adding an extension tube but then I can’t achieve focus. It is possible to fit it all in the frame, but it takes a bit of time. Some images need a bit of processing on the PC once captured as the contrast and saturation can be off as the image of NGC 604 below shows, but others like Mars come out well straight from the camera. So in all I am VERY pleased with this method and look forward to digitising some slides to help someone prepare for a talk, and also to keep their slides for prosperity sake. [the slides below are comercially available ones I also got second handfrom ebay to do some testing; NGC 604 The Planetarium Armagh; Springtime Dust Storm Swirls at Martian North Pole, The Planetarium Armagh; The Sun, slide 679/10 Astronomy Slides, Rickitt Encyclopedia of Slides 1973]
Thanks for the ideas.
Wow.
Never thought about using my DSLR! I’ve just ordered one from ebay. I will report back! Many thanks again.
James
6 and 1 are not dissimilar in form, which should give you an idea of where 6 resides in the overall scheme of things.
7, I think the clue is the initial plateaux phase of the plot.
8 I think is just difficult!
Sorry.
Thank you.
Thanks all. A non-astronomy friend is going to lend me something to try out, so I will report back. I am surprised the flat bed scanners (I have one) would have sufficient resolving power to convert a 35mm slide into a reasonable quality image, this may be something I could try with my own scanner.
Thanks all again.
James
I did the star count last night and could count 12 stars from my back garden; 10 were easy to see, 2 were with averted vision. Will be interested to see the final national results.
James
Lots of ideas above. I think this book is good as it shows you what features are visible throughout the lunar month. Secondhand copies can be sources online for under £10.
Excellent.
I thoroughly enjoyed it. Best of both worlds; I got to hear the talks and stay away from the stinking capital. Well done all involved; I too watched on you tube. I think it worked well for 3 hours or so; I’m not sure I would have sat and listened to a full day. I especially enjoyed the SkyNotes, a very entertaining and informative edition; just far too much on variable stars 😉
James
Excellent.
Great to be able to see the talks from home.
Might be useful if the slideshow of images playing at present were to have some text saying “we are having our coffee break, the video feed will return at about 16:15” or the like.
Great stuff.
James
Thanks Martin. This was 120 x 30seconds, so an hour in total. I’m going to wait until it is higher in the sky and try for 60 second subs, and maybe try without the LP filter. I think the LP filter is also cutting out a good proportion of the cometary photons.
I’ve got an ZWO 224 (colour) but it’s not cooled so I suspect it would be vastly more noisy than my Canon and not significantly more sensitive, but maybe worth trying that too, but I suspect 30 seconds on the ZWO would be VERY noisy.
Food for thought, thank you.
James
Give up…
Will try again in 10 days when higher in the sky and I can take longer subs. Stack below from DSS trying to focus on the comet and the stars. FoV 5.93 degrees x 3.95 degrees; focal reducer flattener is designed for cropped sensors, not full frame sensors which is why I think there are still some obvious gradient rings from some vignetting despite making some flats.
Video of the comet moving over one hour also available here, but 200MB:
https://www.dropbox.com/s/gvtr6kk4mmoouio/IMG_7940_pipp.avi?dl=0James
I think the fundamental issue with my data is:
– subs too short, I will try 60 second subs, but not guiding so will have to get the PoleMaster out
– I stupidly shot in JPEG and need ot shoot in RAW
– I think the comet will be better when higher in the sky.
Here is one of my many stacks, where I forgot to identify the comet as a comet and it’s just stacked on the stars!
James
More info…
Canon 6D with an IDAS LP filter, on WO Meg 72 FD with WO 0.8 focal reducer; lots of darks and flats too.
Peter Hadland Davis (born 1918) was the son of Frederick [or Frederic] Hadland Davis (born 1882/3). So that link is confirmed.
Ian, you certainly don’t need a college education or an in-depth understanding of maths to use a computerised telescope. It is something which is much easier to learn from someone else, hands-on, than trying to read a manual though. If you have access to a local club or society I would strongly encourage you to get acquainted with them and get some help. Understanding some basic maths is useful for some aspects of astronomy, for celestial coordinates, working out magnification etc, but you’ll get by fine without it. Having an open mind, patience and a willingness to learn something new is far more important, as some computerised telescopes are not always as intuitive as they could be.
Good luck.
James
My 14mm Samyang has some aberration at the edge when the iris is wide open; I’d just assumed this was the common given the enormous field of view and the relative affordability of the lens.
James
