Dave Smith

I do like that detached prom. Dave

I would love to have captured a full animation on Tuesday but (1) I didn't know it was happening (2) the clouds kept interrupting which prevented regular timings, so I did keep taking images at random when the cloud permitted. From those these four do give a view of the event. Rough measurement indicates to me that it was erupting at probably in excess of 100 km per second. Maths at the bottom. Size of Earth 4mm diameter of Earth 12 740 km Distance on screen CME moved in 33 minutes 70mm So Speed of CME = 70/4 Earth diameters in 33 mins = (70 X 12740)/(4 x 33 x 60) km/s = 112 km/s Dave

You are so lucky Nigella to catch it from the beginning. I was out before it started and did an image of the whole Sun but no sign at that stage. By the time I had gone round the limb imaging the small proms I came across it when it was quite huge so like you continued to take many images. Also, like you it was my first CME. We are just so lucky and privileged to experience that. Dave

I also have many images of this decaying but still to be processed. They may eventually appear on my website https://mysolarpics.co.uk Dave

White light with Megrez 90 and Lunt wedge Hydrogen Alpha through Lunt 80mm Dave

Very nice 👏 Dave

That is impressive. I did get one in April but no exhaust trail.

Finally have it the right way up. Dave

This view is as seen through my scope. i.e. laterally inverted. I don't know how to invert an animated gif or movie file. More images in white light and hydrogen alpha from this morning and before can be seen at https://mysolarpics.co.uk Dave

Well thank you very much every body for you advice. I seem to be back in business, the new lead seems to have much better contact with the Quark. The lead a microB to standard USB came as a pack of 3. https://www.amazon.co.uk/gp/product/B07HPZVT2K/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&th=1 I only need the one so if any one who gave advice would find one useful then send me a PM and I will happily post one FOC. Here is my first image of this morning. I was very lucky with that arc prom as when I came back to have another look it was gone. Dave

I do like that. Great idea and looks far more secure. Dave

If a new lead does not solve it then that will be my next thing to try.

The good news is that it was working fine this morning. I only had a brief glimpse of the Sun as it is mostly cloudy but I could see surface detail and a prom before re-clouding. So it looks as if I have a connection problem. I tried out in my observatory early on but it showed no sign of warming up even when I changed to a mains powered power supply, but the same lead to he quark. I have now ordered a new USB to microB lead which can get power from my USB hub. Thanks again for all the suggestions. I'll keep you posted. Dave

When I took mine outside today it stayed green but the clouds became rather threatening so all is packed up again. Dave

Thanks for all the helpful comments and also the link to SolarChat. I tried plugging it in again and the light was still amber after half an hour and no sign of any warming up. So I brought in indoors while having a late breakfast. I left it plugged in and to my surprise found the light was green and the red section felt a nice cosy warm. I then turned the dial and it has since returned to green. So I am now desperate to try it on the scope with the Sun but, of course, it is cloudy. To answer earlier questions, the disc of the Sun did look featureless apart from sunspots and before this there had been no degradation of the image. I will report back once I am able to get a glimpse of the Sun.

Hi Dave, I'm not too sure about that. Thefirst time it stopped working it didn't change to green. When I next tried it was a lovely green and I hoped it would then work but alas not. I did try again but not really green. Dave

I have used my Quark successfully for a few years but it has suddenly stopped tuning to see in H-alpha. Nothing has changed in my setup and I am using the same battery as ever. The light comes on but the view as seen by my camera only gives the white light view. After 10 minutes plus there is no change. Has any one experienced this before? It looks terminal to me. I suspect it has gone into a big sulk because behind it's back I have ordered a Lunt 60mm ! I would be grateful for any ideas. Dave

I use an Atik 460Ex with a photometric V filter. I am sure however many CCD cameras would be suitable. One consideration would be the field of view to ensure enough comparison stars are in view. My main interest was once imaging so I do have a filter wheel with sufficient places to take LRGB and Ha,O3,S2 as well as the V. You can screw a single filter onto the end of a CCD camera so a filter wheel is not essential. I used to use an Atik 314 Both Atiks are low noise and I find it only necessary to cool to -10 degC . The chip of the 460 is double the size of the 314. By the way it is not essential that yoou but a V filter straight away. Useful work can be done unfiltered. It is worth getting one once hooked. They are not cheap. I hope that helps a little. Dave

Hi Steve It is better if the comparison stars are of similar magnitude to the target star if possible. I've just had a look at the aavso chart for S Cas and can see that it could be tricky. One of the brighter comparison stars have a few faint ones very close by. Dave

Hi Steve The purpose of defocusing is to help insure that the star image, and the comparison stars are not saturated. I don't go out of my way to defocus but don't worry too much about being in focus. It is important that you check that it is not too close to saturation. S Cas has a very long period, you may find it more interesting to try a star with a short period so that you can detect change. Ther are suggestions on the BAA VS web site. Dave

What mikeDnight has said is very relevant, You can alternatively study eclipsing binaries which have a regular periodic pattern so that you can get the full picture over a number of nights. I have mostly been looking at HADS stars that have a cycle of only a few hours and so it is possible to get one or more complete cycles in one session. See here for ideas https://docs.google.com/spreadsheets/d/1oGA2HaEHE8L6eX19ZoHqQQTu0LYV56HX3Srg7oCtOHo/edit?hl=en&hl=en#gid=883500896 Dave

I've never done that as the stars i have been looking at vary quite rapidly. I was advised that for longer period variations to just submit the individual readings. Dave

Hi Steve, I don't use that method at all. I get the comparison stars from aavso. If that doesn't work I get comparison stars from a star chart program "Guide" which has the UCAC3 star database. Usually the charts from aavso are sufficient. Personally I don't put the magnitudes in at the AstroImageJ stage but later when putting the data into the BAA spreadsheet Hope that helps. Dave

Hi Steve. With SGPro it slews to where it thinks it should but then takes an image, plate solves it and then makes a correction. It will do this until target is in the centre as accurately as you choose. Dave

I find that the plate solving facility in SGPro brilliant for getting the star right in the middle of the FOV. Dave