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Johnny666666

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About Johnny666666

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    Nebula

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  • Gender
    Male
  • Interests
    Film-making, Audio, Photography, Music
  • Location
    Sheffield
  1. Hi all, sorry I've been away for a while but I've been busy with other things... One thing I have an interest in is making films and I've had reasonable successes on the amateur scene. In summer I began making a short documentary about buying a new telescope and capturing images with it, and I need to revive the project in order to finish it for certain competition dates. The idea was to film the setting-up and 'capturing' of images from the telescope, then add my processed images at the end. These would then have been updated with better images over the course of next year when I should have more time to get to grips with imaging DSO's. However, I'm running out of time (and favourable weather) and although I am reasonably certain I should finish the filming within the next few weeks, I have no images! So, if anyone would be prepared to send to me copies of some of their 'beginners' or 'enthusiasts' DSO images, that would be great. I am looking for a total of probably up to 10 images capable of being captured using a Skywatcher 150P or 130P-DS (because they are what I own) or their equivalent. I'm not looking for a 'perfect' image that shows years of study and experience with imaging, but I do need images of any DSO's from the Northern hemisphere that will make a potential audience say 'wow,' even if they are over-processed (the images that is, not the audience!) Unfortunately I can't offer anything other than a name mention in the end credits because I am an amateur filmmaker and paying for 'services' disqualifies me from competitions. The finished film will be in Full HD, so the larger or more defined the image the better. If anyone has any questions then please PM me and I'll get back to you as soon as possible. I can also give links to a few of my other films if required, as well as the first draft edit of some of the footage I have already taken of the telescope documentary. Many thanks in advance - John
  2. I think I've read several times that the EQ3.2 can just about manage 30 second exposures when set up well, so I don't think I'm far off maximum. I'll wait for another clear night and have a second bash at DARV, just to confirm I'm doing it correctly. Unfortunately I have no permanent position for the telescope so I have to put it all together and tackle down after the end of a session. It's no real hardship, just a bit of a pain. Once I've got the 15 - 30 second exposures cracked I'll start experimenting with stacking software, presumably detail can be teased out of faint images in a similar way that Registax does for planetary? Getting a decent exposure time for planetary images is not a problem but if I'm restricted to 15 - 30 seconds for DSO's at low ISO then *I* won't be able to see much DSO detail on screen, but will the software?
  3. Thanks, though you have give me more information and further things to try! In truth my exposures of 30 seconds are beginning to show elongated stars, and I was quite surprised at this when I thought the drift aligning was more accurate. The images I posted are 10 and 15 seconds, beyond this they do show signs of inaccurate tracking. If I can get longer exposures I can ease off with the ISO settings and get less noisy images. I'm not sure what you mean by: "A star to the east near the celestial equator, I use a star at least 20degrees above the horizon." Isn't the celestial equator exactly on the horizon due East or West, or have I got it wrong? Therefore would I be better to try and drift align on a star closest to the horizon or is it not that important?
  4. I think the stars I chose were pretty near to your suggestions, surrounding houses, fences etc means that 'low down' to the South is about 40 degrees for me, and West I am able to get a bit lower, probably quite close to 20 degrees above the horizon. Perhaps I should've made that clearer. I also think the two methods we are using are the same, though I stand to be corrected if I'm wrong. Bear in mind I don't use a computer or any software. I use the camera in Bulb mode, with the telescope tracking at single rate for a few seconds in order to create the blob of the starting position. When the motor controller is set to '2x' mode, pressing the 'W' keypad causes the RA motor to stop running (single rate minus single rate = stopped) creating the first star trail across the image, akin to not having any tracking. Then after a further minute I press the 'E' keypad, which causes the RA motor to run at 2x speed and the scope to slew East (single rate + single rate = 2x speed). This then causes the same length of star trail on the image but in the opposite direction. You need 2x speed (on my set up) to slew the scope East, single rate will just hold the star at the same point on the image, as it should do. If you look at my last DARV images, they are the same as yours, although not as accurate! The only thing I don't do is wait for 5 seconds before reversing direction, but only because this wasn't mentioned in the DARV literature I have. Hope this makes things clearer?
  5. Hi to everyone Following my last (abysmal) attempt at imaging M13 I thought I'd try again, but followed advice from friends on SGL and made a few modifications. Firstly I tightened everything on the tripod, then bought a Bahtinov Mask (what a brilliant piece of kit) and also the Skywatcher Auto Focuser to fit the single speed focusing rack on the 150P to eliminate vibrations when adjusting focus. I set up, levelled the tripod and polar aligned, then thought I'd have a go at drift alignment, as detailed by Robert Vice. Note: all the DARV images below are unprocessed apart from resampling the image size to about 30% and all exposure times were counted by brain with the times below added by checking the EXIF data... Below is my very first ever result, pointing South as low as I can see (10secs tracking, 60 seconds not tracking, 60 seconds tracking at 2x speed, ISO 800) Something was obviously amiss because there was no way the non-tracking and 2x tracking star trails could be aligned so I tried again for a longer exposure time, and reduced the ISO to minimum (10 seconds tracking, 130 seconds non-tracking, 130 seconds 2 x tracking, ISO 125)... Again, not a hint of the star trails drfting out, so I slew the OTA to the West and found a suitably low star. Again, the results looked exactly the same... I even listened to the motors to ensure they were stopping and changing pitch and everything sounded OK to me. Entirely unconvinced that simple PA using the reticle on an EQ3.2 mount could be that accurate, I decided to try something else: I exposed for much longer '2 x tracking' than I did 'non-tracking,' and the result below shows that the star trail does in fact move in one direction, then overlaps exactly and overshoots the initial 'starting' position of the star... Still not entirely convinced that simple PA could produce what appeared to be accurate results I decided to go for a very long exposure time! (10 seconds tracking, 260 seconds non-tracking, 260 seconds 2 x tracking, ISO 125) and this was the result: Somewhat pleased that I had at last encountered a tracking error I adjusted the Alt setting bolts by 1/4 of a turn (I had no idea what direction, I just wanted to see how much effect it had) and exposed again using the same settings. I also added a Baader Neodymium filter to the optical train to judge the effect it had on light pollution: The angle of deviation was less but the finishing point was now below the starting position so I had adjusted the bolts too far. I also think the image is more usable with the Neodymium filter (excuse the tree!) However, the clouds were starting to roll in so I decided to have a go at M13 again. I now have a RACI 6x30 finder (I just couldn't get on with the stock one) but I couldn't see M13 in it, and could barely see it using binoculars but I eventually stumbled across it. Focus was done using the Bahtinov Mask on a star somewhere along the Dec axis (I simply used the fine adjuster until I came across a suitably bright star) then returned to M13. The images I think are an improvement on my previous attempt in respect of both focus and issues with vibration. This is a 1:1 crop of the central part of a prime focus 10-second ISO 1600 image, with added Baader Neodymium filter and post-processed a bit to bring out more detail (and noise!) There is some coma towards the edges of the uncropped image but the central stars I think are much better: This is a 1:1 crop of a central part of a 15-second ISO 1600 image, using the Skywatcher 2 x Barlow lens and Baader Neodymium filter. I just wanted to see what it looked like when pushed harder, again I processed the image a bit to bring out some of the fainter stars: Overall, I am pleased with the results, and any suggestions would be welcome, regarding anything. John
  6. Thank you so much for your kind offer, David - I'll certainly keep it in mind I have a few simple mods I want to try at basically 'low cost' but in the meantime I'll have another bash at the existing set-up and see how I get on. I'm sure I'm doing something wrong somewhere and if I'm setting up on the patio again (I have very little choice) then I'll ensure I'm not moving anywhere when exposing. To be honest, I wanted a set-up that was 'intermediate' and capable of good results to see if the bug bit, then in a couple of years if I still feel the same way then I would like something far better. The GH3 is 'uncontrollable' from a laptop (unless I download some distinctly unstable dodgy looking 3rd party coding) or I have a tablet or smart phone, which I don't. So I would be looking at a camera or imager upgrade as well. It's a lot of expense and upgrades are hard to make future-proof - with the exception of my ability to now use 2" filters throughout my telescope and camera system, something else I need to look at because I do have a spare dovetail and camera lenses from a nifty-fifty up to 600mm. I'm just waiting for clear skies...!
  7. Hi and thanks for the replies Well, the mount seems to check out OK and any perceived stickiness is apparently nothing untoward (it's my first scope so I have nothing to reference it to!) We did notice that there was some play in the backlash of the Dec gearing which has now been dealt with although the RA motor seems fine. The RA lock has also been slightly adjusted to disengage more. I've said I'll go through a series of checks the next opportunity I have - such as any backlash or stickiness when operating either the Dec or RA motors and changing direction, and also see how smoothly the mount rotates when it is fully loaded. RVO have kindly said if I'm still concerned I can take the whole set-up to them and they'll check everything for me One thing I need to check when I'm observing is the small thumb screw that locks the hour setting scale on the RA axis. I never use this (or rather it is always slack) when following the astronomy shed polar alignment routine. However, when looking at the mount tonight I noticed it has inadvertently tightened up due to handling in transit, and this definitely makes the RA rotation less smooth. I'm also going to have a look at the video footage of Mars and Saturn I took on Saturday from the same location, because I remember walking away from the mount and back to it again, so this might show up any wobbles on the patio!
  8. Thank for the reminder - I often forget the planets are in their own orbit! Such is the curse of a newbie Hi Louise, Aside from the focusing issue I do trigger the camera from a 5 metre remote control, but I now realise I might not have been standing far enough away - or at least that's something I need to be aware of next time. The camera can be controlled via WiFi with an app for a smartphone or tablet, but unfortunately I have neither and the app/program doesn't work on humble laptops as far as I know. Off to RVO in a few minutes so hopefully they can do something with the mount, if that's the issue. I'll update later
  9. Thanks everyone :-) Yes I realise focus isn't brilliant - this is something else I am having issues with but I just wanted to capture something for the first time other than the moon or a planet as the exposures etc are quite different. It was more of an experimental shot to be honest to see how accurately the mount would follow the stars. I polar align using the astronomy shed technique and haven't really had any issues with it although I've noticed my videos of Saturn and Mars lately have been drifting across the camera frame over the course of a couple of minutes so again something isn't right there either. I was expecting to see star trails of M13 to be honest but would've expected to see them as perfect straight lines, not this kind of weird wobble. Unfortunately setting up on the patio is my only option if I want to view anything south (I had been imaging Saturn earlier) but I can set up on ground at an alternative location if I want to only look at anything north, so I might try this at some time. The mount definitely appears unevenly stiff when rotated in the RA axis. Even if the scope balance is some way off and I tap the weights to see which direction it moves, it sometimes only moves a fraction. Yesterday I put just the mount on a table with only the weights bar attached and unlocked the RA lock so that it rotated 'freely.' When I rotated the RA axis in one direction so that the weights bar was horizontal (90 degrees from 'home' position) and then released it, it freely swung back down to 'home' position. However, if I rotated the weights bar horizontal in the opposite direction (say, 270 degrees from 'home') and let go, nothing happened, it just stayed where it was. Even tapping it down resulted in it only moving a few degrees so it's definitely stiff around that area. I also use the dual motors to 'perfectly' align an object in the EP (I prefer this to using the fine controls because the motor buttons are all in my hand and I don't have to touch the scope) but when I change direction I can hear the motors change instantly but there is a delay before anything happens. I'm aware there might be some backlash in the various gears, but once this has been taken up there is usually a sudden movement and the object I am viewing darts across the EP. RVO have said that the mount might require some adjustment and have very kindly offered to look at this for me tomorrow as I said I wasn't keen on making any adjustments myself, so hopefully that (and a revised or more accurate polar/drift alignment technique) is all that is required. Oh, and a Bahtinov mask
  10. Hi to everyone, As it was such a clear night on Saturday I tried for the first time to image a DSO, namely M13. I had previously levelled the tripod and polar aligned as best I could (I'm not yet at the stage where I have had a play at drift alignment) but managed to grab a few shots. The results are disappointing to say the least because even a 5 second exposure shows what appears to be star trails. However, looking at the images in the cold light of day I'm not convinced that it's simply misalignment. I've attached an image of crops of M13, the left hand image was 20 seconds exposure, the right hand 40 seconds. I did nothing apart from adjust the exposure duration and the shots were taken immediately one after the other. The trails show up as a weird 'S' shape and actually change direction between each image. The mount is fitted with motors and I am aware they are not the best in the world however I would've expected better performance than this. The shutter was delayed so shutter shock shouldn't have been an issue and the set-up was on a patio so little chance of the ground moving. The camera was fired using a 5m remote cable, so again nothing was moving the mount apart from the motors. I have noticed that the mount has become quite 'stiff' and even from new balancing has always been an issue because I appear to be able to adjust the counterweights quite a fair amount in either direction before the scope swings off balance. Any thoughts or comments would be welcome as I would really like to start imaging DSO's to at least the best that my budget equipment is capable of, but I feel something is not quite right at the moment... Regards - Johnny
  11. Very interesting point about the extra thumbscrews! I have often wondered about the effect on the image all this stacking of adaptors has - I have sometimes noticed on the 150P a small amount of play, depending what combination of adaptors I use. With time I will replace some combinations with purpose designed adaptors. Sorry for the extra questions: You mentioned the Baader MKIII gives a 'better field' than the Skywatcher - do you mean quality of image or wider angle? I assume the 0.9x reduction of the SW CC gives a slightly wider field of view than the 130PDS would be capable of in prime focus? Spacing distance: is this the distance from the sensor to the front of the adaptor? I'm not familiar with M48 mode - is this a fitting you use to connect to your DSLR or is it simply a large standardised thread system for assorted astronomical paraphernalia? The m43 camera system has a sensor mounted much closer to the front of the camera than is usual (they have ditched the mirror) but unless I pay out £50 or £60 for a custom low profile T2 adaptor all adaptors I have seen move the m43 camera as far back as any other system - therefore I have a small issue with the 150P where the focussing tube is intruding into the tube assembly in order to attain focus.
  12. Cool! I didn't think there would be any issues but I just wanted to know someone else had tried it first! Many thanks
  13. Hello to everyone, I have a SW EQ3.2 mount which I've motorised, but I'm finding the cables inconveniently short between the handset and the motor. I believe they are RJ11 connections so I'm wondering whether anyone has tried using short extension cables, say 2 or 3m length? Many thanks in advance
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