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Posted by A R Pratt at 10:44 on 2012 Sep 07
Hi Martin,Some skilled exponents of Registax have written detailed descriptions of how they process their images, but these can be very complicated and confusing for the beginner.Paul Maxson has written a nice tutorial on getting started with Registax 6http://www.astronomie.be/registax/previewv6paul.htmlRegistax 6 runs very quickly on a multi-CPU-core computer.Good luck, Alex.
Posted by M C Butcher at 09:59 on 2012 Sep 07
Alex, Many thanks. I’ve downloaded Registax. I now need to learn how to use it! All I need now are some clear skies, never mind we can’t have everything.I am most grateful for your help.Martin
Posted by A R Pratt at 11:08 on 2012 Sep 05
Hi Martin,Yes, the photos were taken at prime focus of the 20cm aperture f/20 Mak-Cass. I also have an Apo Barlow lens with built-in T-mount adapter, which gives more magnification.Lunar images at 4000×3000 pixels are beautiful to look at, and are nice to use in presentations.A time delay of a few seconds between exposures shouldn’t be a problem for most lunar images. For example, the shadows cast across Plato during sunrise can be seen to change over periods of 15 minutes or so, but if you can take a series of images within 3 or 4 minutes they should be OK.Registax is free to download and use, and its website has some good tutorials to get you started.Cheers, Alex.
Posted by M C Butcher at 09:52 on 2012 Sep 05
Alex, Very many thanks, I’ve had a look at your image in the LSC which is a delight. I can achieve results almost as good but it is more by luck than judgement and my question was aimed at improving my success rate a making my astrophotography more a science than an art. Whilst I realise that your photo was at f/20, was that at Prime Focus or using Eyepiece Projection? I presume the former but it would be interesting to know. Obviously I will need to get a copy of Registax to have a go at the stacking. Many thanks for your help.Martin
Posted by M C Butcher at 09:38 on 2012 Sep 05
Andrea,Thank you. The Canon 40D also has the ability to take images in quick succession which I have tried, so far without success as the mirror moves up and down between each exposure. Your point about collecting all the images within a shortish timeframe is understood. Do you know how to calculate the maximum period over which to take the images before the rotation will start to impinge on the image?Martin
Posted by M C Butcher at 09:35 on 2012 Sep 05
Roy,Many thanks, I forgot to say that I do use a remote control release anyway. But thanks for the rest of the advice, registax would seem to be worth a try.Martin
Posted by Steve Holmes2 at 22:57 on 2012 Sep 04
Well – Wednesday is the Big Day, apparently! Richard Miles tells me that Council will be debating the JBAA Papers topic then. I had hoped to liaise with him a bit more about the details but he’s been quiet for a few days, possibly because of an "incident" with his PC caused by a power surge (as discussed elsewhere on the Forum!).However, let’s hope Council have a fruitful discussion and take on board something of what has been debated here. There’s clearly a lot of interest in the topic, judging by the "views" total (will we make 500?), so it would be a shame if nothing positive came out of it. If there’s anything "for public consumption" that I get informed about I shall, of course, be back on the keyboard.Steve Holmes
Posted by A R Pratt at 21:08 on 2012 Sep 04
Hi,As well as lunar imaging with colour and mono webcams, I also use my Canon EOS 500D on my 20cm f/20 Mak-Cass ‘scope.Likewise, I use mirror lock and the self-timer delay. The mount is driven at lunar rate, I carefully align and focus on an area of interest using Live View, then I take up to 30 shots with the self-timer option, pausing a few seconds between each shot, to allow vibrations to die down.BMPs are then stacked and processed via Registax.An example is given on page 15 of the 2011 May Lunar Section Circular. (This is just a small crop from the original.)It’s nice to work with large images instead of 640×480 pixels from some webcams. I occasionally add my Apo Barlow lens (with T-mount) to increase the magnification.Clear skies, Alex.
Posted by Andrea Tasselli at 20:52 on 2012 Sep 04
If I remember well the D40 has burst capability so that you can take a number of shots very quickly. I would use it if available. The trick is always to take the greatest number of shots in the shortest time available by the body you’re imaging. For the moon this is set by the speed of the advancing or retreating shadows more than anything else, which should be in the several minutes at least (shortest when the moon is closest to the sun and longest when it’s in opposiiton to the sun). The best way to use the shots you’ve taken is always to allow a program such as Iris or (alas) Registax to quality-filter, align and stack them up. Use the final stacked-up image to do all the contrast enhancements required.Andrea T.
Posted by Roy Hughes at 12:24 on 2012 Sep 04
I would think that using the Self Timer is very much second best to using the Remote Release cable (£6.90 on eBay) – you should be able to squeeze off more and steadier shots, improving your chances.Don’t know Images Plus. I use the classic sony webcam on luna craters. Then Registax for stacking and it works great. Watching it do stacking and alignment in real time is mesmerising. As Registax is free I’ve never felt the need to use anything else. Might be worth a try?
Posted by Americo Watkins at 15:58 on 2012 Sep 03
thanks David,I know a couple of people who also use these and they seem to work. Will take a look at them.Eric
Posted by Grant Privett at 15:11 on 2012 Sep 02
Lovely Uranus images at 685nm. Certainly highlighted the differences between different nights…
Posted by D A Dunn at 16:51 on 2012 Aug 31
Hi,Just a comment. Living in rural France as I do we suffer from all manner of voltage fluctuations. On my computer network I have 2 UPSs. One for the network drives and one for the "master" computer. They will hold the system up for at least 15 min. They also block any spikes on the line. I am sure they would also protect any other sensitive equipment.RegardsDavid
Posted by Anthony Rodda at 22:16 on 2012 Aug 28
I tried several packages recently before buying AAv5.I already had CCDSoft v5, AIP4WIn and Guide. Agree completely with the sentiment that no one package does it all.I use SX and Sbig cameras mainly for photometry. AA has IMHO very easy calibration and colour procedures and the camera control is good.What I really like is the astrometry and photometry "calibration" of images using the inbuilt (GSC & USNO) star atlas.Just being able to open an image and plot RA and Dec with photometry readings direct with a few mouse clicks is impresssive.RgdsTony
Posted by Callum Potter at 18:00 on 2012 Aug 25
Hi Paul (A),I have been copied on a number of Uranus (and Neptune) images taken by Marc Delcroix et. al. at Pic du Midi using the 1m scope.If you have not seen any of these, i can probably forward them on.Or i think you can find them at:http://www.astrosurf.com/delcroix/index_en.htmgo to Planetary Images, then Galerie d’Images, then scroll down.Callum
Posted by Paul A Brierley at 16:22 on 2012 Aug 25
Dear Paul,Now Uranus is out of the murk, I’m seriously tempted to have ago. At observing this under observed planet.I have a modest 250mm 1200fl F4.8 Newtonian, with some good quality Vixen LV’s and a x2 Barlow. The highest practical power with this equipment, when the seeing allows. Could be x400 and on rare occasions x600. So I should see the planet as a tiny disk. Whether I can resolve any cloud belts is another matter. However I will let you have any observation’s and drawings if you wish.
Posted by Paul A Brierley at 20:25 on 2012 Aug 24
What about Nebulosity. This is another very good program, written by Starklabs, who also write PHD.A friend of mine has a H18 and he uses Nebulosity all the time.It is very cheap. Compared with AstroArt
Posted by Andrea Tasselli at 20:18 on 2012 Aug 24
I can’t say about AA as I always found it a bit akward to use but difference in functionality between SX software and MaximDL could be greater. Sufficient to say that I can guide with one and I can’t with the other.Andrea T.
Posted by Steve Holmes2 at 01:22 on 2012 Aug 24
Excellent! Two more meaty contributions to reply to. Andrea’s first:-If the Association’s Charter does indeed refer only or mainly to the promotion of observations then there might well be reasons for certain classes of submission to be turned down. However, to have a submission rejected because it is "contrary to the Bye-Laws" is quite different from having it initially accepted and then rejected after review. Submissions in the first category should be rejected by the Papers Secretary or JBAA Editor, and of course there should be information about this in the Guidance to Authors so that prospective authors will not waste their time writing inadmissible papers. However, once a paper has passed this hurdle it has clearly been deemed "appropriate to the Journal" and thus suitable for publication if its content is acceptable.Andrea’s comment a) simply affirms the point I was making at the time: judgements of this sort about the acceptability of a submission can only be the opinion of the person making them, not of the whole membership. This is exactly the reason why perceived popularity must not be a criterion for assessing papers. His comment b) contains what I assume is just a "slip of the pen", when he refers to the popularity of "articles" when I was actually talking about "papers". However, what he ends up by saying is perfectly correct – the popularity of "articles" i.e. submissions of a general or journalistic nature, should very definitely be the concern of the Editorial team as that is what makes the Journal interesting as a whole. It does not apply to "papers" though. One does not subscribe to a solely paper-publishing Journal for the pleasure of reading the papers, but because one feels that information will be gained from them. The JBAA is somewhat different, in that it contains both "articles" and "papers" but, as I have said on a number of occasions, the two classes of submission should not be confused. And no, it is obviously not the case that merely having scientific content grants to a submission the right to be published – but then, I’ve never claimed that it does!Comment c) is, I think, covered by my preamble. Whether or not a certain class of submission is acceptable is a matter for the Association as a whole and the JBAA Editorial Team in particular, but exclusions must be made explicit, not implicit.Finally, I am at a loss to understand why Andrea thinks that amateurs attempting to measure up to professionals is "ridiculous" and "snobbish". We clearly cannot equal the volume or span of their work but we can certainly aim to equal its quality and most particularly (and this was the actual point I was making) their professional standards. The reason why we should all strive to do so may be "beyond" Andrea but I hope it will be only too obvious to the bulk of the membership.Moving on to Richard’s excellent contribution, may I say how pleased I am that someone is at last taking a constructive view of all this and accepting that, just possibly, there might be areas where process improvements can be made. I am also gratified that he found my paper interesting!The suggestions in his last [main] paragraph are all good ones which I feel should very definitely be considered by the Association. As he says, there may be other ways of doing things in this online age. His mention of the other already-existing BAA publications reminds me to highlight my view that some of these might be a better place than the Journal to publish submissions which are not really papers under the standard definition. I do recognise that cost would be an issue if the existing Journal were to be split though, so would re-iterate that publishing both papers and articles in the one Journal is fine as long as the two are not thereby confused.Finally, I would of course be delighted to publish my paper at "arxiv"! I had rather assumed that this archive was the domain of professionals but, taking my cue from my response to Andrea, I would be very keen to use Richard’s expertise to help me stand alongside them – many thanks for the offer. If he could email me some further information at steve.britastro@holmesfamily-UK.net we can see what might be possible.Steve Holmes
