There's an old saying, 'If you want to give the gods a laugh tell them your plans for the future'.
My plans were along the lines of spending the very light nights setting up and testing ASCOM, PHD2 and other software and practising my post processing. What actually happened was that my laptop died, taking with it all of the settings that I'd struggled to figure out - but hadn't noted down It also had lots of personal data that hadn't been backed up recently so a new laptop and dozens of ho
'Calculating the Cosmos' by Ian Stewart and 'The Universe Next Door' a New Scientist compilation are both extremely enjoyable reads and have kept me going in between the'dark clear nights' here on the east coast. So having time on my hands this summer, I prepared a digital image and poem in 'homage' to two of my favourite pursuits: reading books on cosmology I barely understand and eating shellfish most people tend to avoid.
'Winkles in the fabric of Space-Time' - mixed media - Geo
I'm hoping this is my final and hence "Ultimate" generation of all sky cameras. Based on the ASI185MC CMOS astro camera and Fujinon fish-eye lens of 1.4mm focal length and f1.8. Image capture is provided by a Raspberry Pi 3 in conjunction with INDI drivers. This is used with KStars/Ekos client software running on a Linux Mint desktop indoors. Communication is via Wi-Fi. The astro camera is an uncooled version but I have added a Peltier TEC cooler. This cools the camera down to something li
I'm starting with an empty area about 10 x 4 metres between sun lounge and observatory in front of living room window and facing roughly south. I have killed off most of the weeds and grass by covering with an old tarpaulin for a year or so. This has also stopped the ground from drying out and making it easier to dig. In addition to providing a path to the observatory, this will provide flowers and shrubs to see from the living room window. Plus a small pond and fountain. The latter is som
Well I have been studying the various ways of looking at the night sky now for the last 9 months or so , after wanting some means to do this for a long time and finally have the time to put some cash into it.
So here in this blog I will attempt to document my path and try and keep myself on track.
My main interest is astrophotography so I will start with the equipment I have or intend to obtain , with comments
Book: Make Every Photon Count: Bought on recommendation of folks in
Having wanted to do astronomy properly for decades I finally took action late in 2017 and bought a pair of Canon 15x50 image stabilised binoculars. I was absolutely blown away with what I could see using these from my garden with what I now know are Bortle 8 very light polluted skies. For the first time in my life I saw the Orion Nebula M42 - only as a small cloudy area but I knew there was more to see with better optics.
When I saw the Pleiades, directly overhead, for the first time I knew
This was taken 8th April 2016 from an apartment in Hamilton Island, Australia. The equipment I used was a Samsung Galaxy S5 and an old but good quality pair of binoculars left by the owners. The skies were incredibly dark and we were able to attend a talk by a local astronomer who guided us around what could be seen with the naked eye.
I was delighted last year when I used Stellarium last year to look at the view on that date and confirm that I had indeed captured Jupiter and 4 moons
The aluminium tripods that come with a majority of beginner and mid-range scopes have had a bad name for years as being poorly made, sloppy and people have tried various ways to make them sturdier such as filling the legs with sand, lead shot, or even expanding foam.
I just read an account the other day of where a person was fitting steel rebar into the legs to see if it will help…
The only problem with these solutions is that you end up with a very heavy cumbersome tripod that is really no
I've been mainly working on the stack inspector this week. The idea is to be able to quickly inspect the entire stack, rejecting bad subs (this also applies to calibration frames, though fuller support for calibration is the main task for next week). The stack inspector also allows animation of the subs and/or stack, making it easy to diagnose tracking issues etc. There's the option to restack based on an arbitrary sub in case the keyframe chosen isn't too good. One thing I'm finding a great sur
Having played with water cooling for astro cameras and seen this applied to 3D printers instead of fan and fins for cooling hotends but at high cost, I though I would like to try myself. I have reasonable DIY skills Some filament types benefit from a heated chamber and warm air is not so good for cooling. This is one example where water cooling is particularly beneficial. Another benefit should be reduced weight for the X carriage permitting faster acceleration and deceleration for fast pri
Since shortly before xmas I've been developing a piece of software to support electronically-assisted astronomy (EAA). Realistically it is still some months away from release, but the main design elements are getting close to being fixed so I think now is a good time to document what I'm doing in the hope that any comments or suggestions might be taken on board before the thing fossilises too much.
The tool -- codenamed Jocular -- aims at promoting observation, but getting the most out of t
Toot and I had a great time in Norwich last night. Dr Michael Foale CBE gave a talk about his life as an astronaut to a packed audience at the University of East Anglia. What an accomplished, kind and measured man. A couple of hours in his company passed very quickly. He has great interpersonal skills and although we only spoke to him very briefly, both my partner and I felt we had 'met him' rather than just 'heard him' speak.
What an exciting, if not at times scary, life and career he has
In an earlier post I examined the noise in single dark frames over a range of exposure times. My conclusion was that the Nikon D7500 was a lower noise camera than the D5300. This was also backed up by an examination of master bias frames that again strongly favoured the D7500.
The first image I attempted to produce with the D7500 exhibited very strong streaks in the noise.
I had been in the habit of not using dark subtraction with the D5300 as it has very
Christmas upright Armchair Astronomer 'transforms' into horizontal Settee Astronomer without any visible expenditure of energy as Moon obliges by rising almost directly in front of his sitting room window. I could get to like this 'indoor astronomy' as it offers a warmer winter alternative for the older stargazer.
Sir John Herschel at the Cape of Good Hope
Having spent the years 1825 to 1833 cataloguing the double stars, nebulae and clusters of stars visible from Slough, in the south of England, John Herschel, together with his family and telescopes, set sail from Portsmouth on the 13th of November 1833 bound for Cape Town. As detailed below, in an extract from his book, the family enjoyed a pleasant and uneventful voyage and arrived some 5 months later at Table Bay with all family and instrument
Every Autumn our local pub organises a charity auction evening. As one of the lots I offer a voucher for 'An evening of Astronomy'. This blog shows the outcome of the last winning bid as posted on the local website, warts and all.
Cashing in on photons
A short article on an outreach at the Bishop Monkton observatory
Sunday the 22nd of October 2017, a week after the annual auction at the Lamb and Flag, the owners of the Astronomy Evening voucher from 2016 made it to
Below is a comparison between single dark frames taken with the Nikon D7500 and D5300 with exposure durations varying from 1 sec to 240 sec ( my usual main light frame exposure ) all at ISO400.
Firstly a graph of the standard deviation of the noise in the dark frames versus exposure time:
The standard deviation of the noise is a fairly constant 2 ADU less for the D7500 compared to the D5300 ( pretty much the difference in the read noise between the two )
However, the differen
The Nikon D5300 has a well-earned reputation as one of the lowest noise DSLR cameras used for Astrophotography. Now that I have a new Nikon D7500, I was keen to see how it compared to the D5300 in terms of the level of read noise and the extent to which that read noise is non-random ( and thus needs to be removed using a Master Bias frame to prevent it summing up during image integration).
So here goes ...
A single bias frame Nikon D5300: ISO400, 1/4000th second:
It was love at first sight when I first laid eyes on the gorgeous noise curves of my dear Nikon D5300; young and beautiful with a great body and a large sensor, I was smitten. Now, well, what can I say... my roving eye has spied a new beauty; younger with heaps of energy that should go all night and , whilst I do prefer larger sensors, I can’t stop thinking about the noise curves hidden beneath that lovely new body...
I struggled with my guilt for ages, I really did, but the time has com
Just got back from Iceland having enjoyed a few days sploshing about in the geothermal waters, looking at waterfalls and geysers and eating lots of cod. As you can imagine, we were very excited at the prospect of seeing the Aurora Borealis. Unsurprisingly, nights went by under a dense blanket of cloud. Then, on the morning of the last full day of our holiday, the sun came out and so did we. After a full 10 hours traipsing about a glacier and investigating basalt columns on a black beach we ret
This is my latest generation of all sky cameras and based on the ASI178MM followed by ASI185MC CMOS astro camera and a Fujinon fish-eye lens of 1.4mm focal length. Although rated at f1.8, this lens lets a lot more light through than this would imply. Image capture is provided by a Raspberry Pi 3 in conjunction with INDI software. This is used with KStars/Ekos client software running on a Linux Mint desktop indoors. Communication is via Wi-Fi. The Mark 6 ASC has proved inadequate after being