baggywrinkle

This image appeared in this weeks Economist. If it were not for the regime North Korea would seem to be a good place for astro photography... I have lived in both Tokyo and Shanghai and can attest to the light problems there.

I have the AZ GTi and have used with an Altair 102mm refractor. It did not protest. The tube weighed in a 5.5Kg with a diagonal and finder.

The waxing Moon last night. Despite the very high cirrus clouds the seeing was pretty good. All on the 12" Meade. Cannon 650D for the whole shot and the AA178C for the detailed shots, no barlow used. Pretty pleased as I got craterlets only 2 Km diameter on the base of Plato showing nicely.

After being in Oxford for the Society of History conference I got home and had some clear skies. Same setting and cameras as for 10th April.

Thanks for that info....'sits back and thinks....' Mmm new camera. The Meade 12" is an F8.

I agree with the above, be less aggressive with the wavelets. My rule of thumb is the if you start with sliders 6 & 5 you can wind these up to 50% or more, after that 3 &4 then less with 1 & 2. I alter the sliders in pairs and perform a 'Do all' between to see what the effect is and what noise is being introduced.

Some grabs from last week, had to wait until this Sunday to process as I was away at a Socieity for the History of Astronomy Conference in Oxford..that was superb My usual set up, all done on the Meade 12", the whole shot a 4 panel mosaic using a Canon 650D, the detailed shots using an AA 178C camera with and without a 2x Barlow, The seeing was a 4 on the Damian Peach scale. The shots using a Barlow are a bit soft which is an indicator that I was on the edge due to the atmospheric interference in the unstable skies over the UK.

One of the deep interests I have in the history of astronomy is that of the Far East, having lived and worked in both Japan and China. The Science Museum in London has a lovely example of a start chart by Shibukawa Harumi from around 1698. Not having the spare £5-8K for an original I decided to buy a repro. This one mounted on canvas, I am very pleased with it. This is of the central section of the chart and shows the stars and their asterisms used from around 1100 to 1922 until the IAU 88 were formulated. You can see one constellation that is familiar to our eyes, for us the Plough, for China , Korea and Japan it is the Northern Rice Ladle Though the charts asterisms and names are based on those used by the Chinese from 500 BC, this, the Japanese, star chart, the Tenmon Bunya no Zu was the first star chart that corrected what it saw as errors by the Chinese.

I bought the SW SA tripod to use with my Star Adventurer mount and thought it might have big vibration/wobble issues. With the Star Adventurer I am generally using my Canon or Sony cameras for widefield and I have also used it with a Coronado 60mm Solar scope as well as a 70mm Altair Starwave refractor I have not had any big issues with regards vibration. I can say the same with the AZ GTi on the SA tripod and a much heavier tube on Wednesday night. If the Star Adventurer tripod is used with the EP holder plate fully clipped in position it is reasonably stiff. I bought is for grab and go and have taken it to New Zealand because of the light weight I can appreciate the EQ5 and Berlebach adapter you are using would be incredibly solid.

I thought it quite quiet, a whir rather than the sound of a tank track. Certainly quieter than my LX850!

Skywatcher AZ-GTi mount I recently bought one of these as a simpler alternative to my normal outreach set up and as a potential grab and go setup to take on holidays. It has had good reviews and that was another reason for buying. The other night with a full Moon preventing too much work with the big telescope I gave it a test run and I was very impressed. Having previously read through the totally inadequate manual, downloaded the free Synscan Pro software to my android phone and watched the YouTube video I felt I was ready for the great outdoors and a live test. The mount can also be operated with a Skywatcher standard Synscan handset which is a nice touch if you run your mobile/tablet down….or forget it. BTW the You Tube video (Astronomy & Nature) is excellent and fills it the holes the manual does not. The manual says the payload is 5Kg. My Altair Astro 102 mm Starwave weighs in at over 5.5Kg with a camera attached. Throughout my test this did not seem to worry the performance. This was all mounted on a Skywatcher Star Adventurer tripod with the extender. The SW SA mount deserves its own review, I have found mine stable even though lightweight. With a full Moon and scudding clouds, I decided on a one-star alignment. I levelled the OTA and pointed it north turned on the power and then linked the android software with the mounts own built in WIFI. It all linked up seamlessly even though there was a message ‘ WIFI might not be available’, I ignored this. As it was night the software defaulted to red light. It is easy to use, though confusingly the Solar System object selection is found under the Stars tab. I chose Sirius as my one star. Another criticism on the software was that I had previously downloaded it to my mobile from the Skywatcher web site and then had to make another massive download for updates to the software as it would not initially link up to the mount wifi. This was when I was indoors and familiarising myself with the set up. Why cannot Skywatcher just get the right package up on their website? The AZ-GTi takes its time date and position from your mobile or tablet, it then slews to the chosen target and tells you when it thinks it is pointing at the target. You then use the directional keys to centre it and press enter. Even with an excess of load the motors did not sound as though they were straining. A slight criticism here was that when hitting the down movement key I would often somehow hit the home button on my phone. Recovering from that was not a problem though. The initial alignment was quite good and once centred I sent it to look for the Moon which it duly did and landed the Moon in the centre of my live view screen. I then left it tracking for 10 minutes on its own to see how good it was. It was very good, the Moon was just off centre when I came back. Next, I keyed in M45 and away it when and was only just off centre, which I thought remarkable for a single star alignment. I also tried Alcor & Mizar with the same result. Had there been less cloud I might have tried a two-star alignment to get better accuracy. As this was being used only in AZ mode I would not try longer then 20 secs for deep sky, but it will be perfect for late cycle Lunar shots when the Moon is too low for study from my observatory. There is an option in the software to mount and use the AZ-GTi in an equatorial mode. I was concerned that the weight of the OTA & camera might overburden the AZ GTi and the SW SA mount and when focusing the wobble would not die down. I need not have been worried, the wobble damped out very quickly. I thought this was a good set up, it also folds down very nicely and would pack easily into a back pack or suitcase for flying. The AZ GTi is 1.3Kg and the SW SA mount with the extension weights 2.75Kg. There is a selection in the menu to allow you to use the AZ GTi for solar observing which is quite useful. I have not tried that yet. Skywatcher have made that menu accessible only after answering a simple mathematical question which should ensure you could not accidently engage it and inadvertently point your scope and damage your eyes. You can power from a power pack but on this occasion, I used 8xAA batteries. What I liked: A compact grab and go mount with a decent payload capacity, the WIFI worked seamlessly. What I did not like: Lack of documentation. This could be a more serious problem for a beginner or less experienced person. Conclusion: A very nice travel mount with some very powerful tools in the software. I still love my Star Adventurer but that is more for photography than for a night under the stars doing visual.

The Philips Guide to the Moon is worth the money. Some decent maps and a day by day account of what is being revealed along the terminator. I regularly image the Moon and it never disappoints for new details being revealed. It takes just over 18 years to complete the Saros cycle. This is where the orientation of the Moon due to its libration on NS and EW axis' caused by its rotation around the Earth presents the details in exactly the same position to our viewing. The Mak 127 is a good lunar instrument. Don't over power it. I have found for visual zoom EP is a good starter to establish what max power can be used on a particular evening due to seeing condition. Then you could swop to a dedicated ep that gives better contrast.

The other thing I have tried on the last three opportunities when processing the images with Autostakkert at the stacking stage was to apply 1.5 drizzle. It makes for a slower stacking but it improves the smoothness without loss of resolution. I have also noticed that images processed this was when sharpened with wavelets in Registax can have the sliders used a bit more aggressively without bring in too much noise or artefacts.

It was the best I have seen it in a while. I am beginning to appreciate the weather forecast that mention the jet stream movement. It had moved north so the seeing in the south was better....sorry Scotland.

The Moon captured on Sunday night. Again windy, so the dew shield was off the 12" Meade. Seeing was very good, around 4 on the Damian Peach scale so I was able to attempt some higher magnifications using a 2x Barlow on the Altair 178C. All images (expcept the whole shot) 1000 frames with the best 25 -40 % stacked. Whole shot a 4 frame mosaic using the Canon 650D at prime focus.