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Posted by Graham Relf at 16:36 on 2011 Jul 14
On my own site I show how to take non-trailing photos with a simple camera on a fixed tripod, stacking with my own software which you can download. The page is here. On subsequent pages I show how you can go on from there to DSLR, equatorial mount, and so on.Sometimes I don’t have my equatorial mount available, only DSLR and fixed tripod. So here’s an example of a photo I took of Comet Hartley and the Perseus double cluster last year, on fixed tripod: here.I do recommend you experiment with the simplest equipment first. You will be amazed what today’s cameras enable you to do (with a bit of software).
Posted by Callum Potter at 16:18 on 2011 Jul 14
Hi Opu,you could make yourself a ‘barn door’ or ‘scotch mount’ – it is a very simple device for tracking at the siderial rate, and quite portable. There are many internet sites that explain how to make one, and there is also an article in the latest Sky and Telescope (August 2011) with a very minimal design (but a bit US centric).Also in the August 2011 S&T is announced the Vixen Polarie tracking mount, which looks somewhat more compact than the astrotrac, but is not yet available to buy.Finally there is also the Orion Min-EQ Tabletop Equatorial Telescope Mount for which a drive is an optional extra. I am not sure how good the tracking is (not the best I am sure), but might be adequate for short exposures (up to a minute maybe).Or there is always the option of a small equatorial mount head, like one of the EQ range, or a vixen polaris.I hope this helps.Regards, Callum
Posted by Naimul Islam Opu at 15:25 on 2011 Jul 14
Andrea… many thanks for the suggestion! I like the software, the link is very useful for me… indeed! ahh the problem with LX90 is the weight I cant move with thats kind of tracking device from up Himaliyan regeion to Bay of Bengal 🙂 I’m trying to find out something easy to carry with backpack, I think a decent tripod will not surve my pourpose coz i want to visualize the backgroud of the sky, Milky Way, other deep sky objects as much i can able to show in to the frame… also i will use 16mm lens, 24mm lens, 28 etc… clear skies! Opu
Posted by Andrea Tasselli at 11:52 on 2011 Jul 14
Sorry, diregard my last suggestion. Obviously you can’t do that. I must had the brain in black-out.Andrea T.
Posted by Andrea Tasselli at 09:50 on 2011 Jul 14
Hi Opu,You don’t need any equatorial platform to get deep sky images with a 28mm lens, just a decent tripod (or you can use the one of your SCT adding a bracket for cameras to the tube) and a remote to operate the camera. You can shoot for up to 15s around the celestial equator (and longer toward the poles). You then stack the set of images using the procedure and software described here:http://astrosurf.com/buil/iris/new430/new430_us.htm (scroll toward the bottom)Alternatively, you could use the LX90 in a fashion if you can lower one leg enough for the tube to point to the North Pole and adjust the position in azimuth of the mount. This is a kind of makeshift equatorial that could potential provide up to 1 minute exposure time (that depends on how accurate your tube axis is pointing to the pole). This should be feasible at your latitudes since the tube inclination is moderate.Andrea T.
Posted by Naimul Islam Opu at 06:36 on 2011 Jul 14
Hello Andrea, my planning to take some wide angel sky photograph, spacially Bangladesh Night sky with long exp.@24mm. so I bought a DSLR sony alpha 200 with some prime lense, I want to shoot from the Himaliyan ground sky (N) to Bay of Bengal (S)… its a very amazing sky beauty, thanks – Opu
Posted by Americo Watkins at 22:51 on 2011 Jul 13
James, thanks for your comments.Do you find collimation stability and any mirror shift a problem? Particularly after any slewing or median flips.I know these can be problems with sct’s but have the newer versions improved on this. I know Meade have a mirror lock. How about the celestron’s. I plan to use an automated draw tube focus.Cheers eric
Posted by Americo Watkins at 22:45 on 2011 Jul 13
Evening Richard Thanks for your comments and advice. I believe I may have replied to you individually rather than as a post on the forum.I’m just wondering about the flat fielding discontinuity as a result of the meridian flip as mentioned by Richard, the results of which might expain Bruce Gary’s remarks in his book "Exoplanet observing for amatuers p.14 2nd Ed. "but the meridian flips invariably produce shifts in the exoplanet light curve and this can be annoying" or maybe not.Would I be right is saying that due to the shift that each of the pixels would not cover exactly the same field therefore the flat fielding would not be identical to the earlier images and hence affect the photometry results.BTW have results for Emma (NB/2) ready just need to work out some mid-point times for stacked images.Eric
Posted by Andrea Tasselli at 08:31 on 2011 Jul 13
What telescope or lens are you planning to use? And what imager? BestAndrea T.
Posted by Andrea Tasselli at 08:27 on 2011 Jul 13
For what you want to do I’ll go for the largest aperture you can afford. Contrary to others’ hints the Meade optics are not bad at all and as far as the field covered is reasonable the image is acceptably flat. More importantly, the Meade ACF optics are liable to be reduced (i.e. made faster) far more effectively than the EdgeHD and are more robust in collimation. If I may add a suggestion is to limit yourself to a 14" in both cases as the 16" is really a behemoth and I wouldn’t want to think how to deal with it alone. Another good thing about the Meade is that they’re cheaper than the EdgeHD.Andrea T.
Posted by Naimul Islam Opu at 04:24 on 2011 Jul 13
Many thanks Paul… no i am not using it with my 8" CPC just planning for wide angel DSLR astrophoto… I saw the link of ‘astrotrac.com’ its quite impressive! 🙂
Posted by Nick James at 21:31 on 2011 Jul 12
Eric,Despite Richard’s advice I wouldn’t spoil a good Celestron by putting it on a fork. Meridian flips are not a big deal with modern GEMs such as the ME and, in my humble opinion, the advantages of a GEM for imaging in terms of balance, flexibility and sky access far outweigh the minor inconvenience of a meridian flip. There is certainly no reason why flat fields should be different one side of the meridian than the other since the instrumental flat doesn’t change and any sky gradient over a narrow field wouldn’t be handled by a library flat anyway.I’m biased since I have a C11 on a CGE but I would go for the Edge-HD Celestron and the ME. Celestron have a reputation for better optics than Meade and the ME will outperform any other mount you might reasonably buy.Nick.
Posted by Paul A Brierley at 19:49 on 2011 Jul 12
Do you want to use this with you’re 8" CPC? Or are you after an alternative?Firstly, if you wanted to use it with you’re current set up. Then you can buy an Equatorial wedge. This will then convert you’re existing Alt/Az mounted SCT, into an equatorial, and it will then be suitable for photography.But if you wanted to just use a DSLR then the Astrotrac is easier.http://www.astrotrac.com/Default.aspx?p=how-it-worksThis is an updated version of the tried and tested, barn-door mount and is very simple to set up and use.If have not done any astro-imaging before. Then I would recommend buying one of these first and see how you get on. Have a look at there gallery page and you can see for your self, just how versatile the Astrotrac is.
Posted by Les Hewitt at 15:21 on 2011 Jul 12
I’m more into deep sky at the moment, but not to the point of excluding anything else that is worth observing. In short, I’ll do anything lol.Someone told me that the next meeting is in November (I think) and I should be there. The Winchester Weekend sounds interesting. I’d be willing to go but would need to know more about it.What I’d most like though would be to take my monster Meade away from city/town lights and get some serious observing done. Only problem is I dont have transport. Help with that will be most gratefully appreciated.Les
Posted by Callum Potter at 10:00 on 2011 Jul 12
If you go to Amazon via the Amazon logo on This Page then things you buy will be accounted to the BAA Amazon affiliation (actually anything you buy from Amazon – not just books).Callum
Posted by Gary Poyner at 22:02 on 2011 Jul 11
Hi Paul,Yes certainly I could act as a mentor to your telescopic observing. I don’t do many binocular stars at all, so Tony would be ideal for this as he doesn’t do telescopic stars!You have my e-mail address. Just drop me a line when you need advice and we’ll take it from there.Look forward to meeting you at the section meeting!Gary
Posted by Richard Miles at 20:55 on 2011 Jul 11
I’m sure you’ll enjoy it – Each chapter is more or less stand-alone and so you can devour them one by one!Richard
Posted by Paul A Brierley at 20:43 on 2011 Jul 11
Hi Roy-Gary.I’ve seen it and bought a copy.I have also signed UP for circulars in pdf format, and joined the section. You might have, already had, an e-mail from Roger about this next question. I wonder whether you, and possibly Tony Markham could act as mentor’s?Tony lives only Ten miles from me in Leek. And he would be the ideal person to arrange a practical, visual, observing session with.I will also be attending the meeting in October in Eccles.
