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  • bark at the.....



    and a close-up



    had a pop at the orion nebula, but by that time, the battery was dying in the RA drive motor ('tracks' the stars) so didn't get anything even remotely worthwhile.

    this astro stuff is a right old journey at the moment
    Last edited by devilgas; 14-03-11, 01:04 PM.
    Dave
    http://www.devilgas.com

  • #2
    Re: bark at the.....

    Can you run your motor off a 12v car socket? Reason I ask is that I run my scope off a 12v power pack the type you jump start a car with, it also has a couple of sockets on it which I plug into. runs the scope all night and more.

    I will post some shots of it along with my poor attempt at M42

    Stu

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    • #3
      Re: bark at the.....

      Originally posted by Goatsmilkuk View Post
      Can you run your motor off a 12v car socket? Reason I ask is that I run my scope off a 12v power pack the type you jump start a car with, it also has a couple of sockets on it which I plug into. runs the scope all night and more.

      I will post some shots of it along with my poor attempt at M42

      Stu
      not sure stu. it runs off a single 9v battery. i used the one supplied with it, but it was one of those mega cheap ones. will try a few duracels and see how they get on. haven't read the spec on the motor drive so don't know if it'll take 12v direct. failing that, i'll rig a 9v regulator to a 12v battery, or just build a 6 D cell battery box. the drive is pretty basic. it has sinlge pot to control the speed and a switch to alter drive direction.
      Dave
      http://www.devilgas.com

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      • #4
        Re: bark at the.....

        I have a 300mm f/2.8 telephoto and a 2x converter, so an equivalent of 600mm f/2.8 and on an Olympus body that's 1200mm equivalent (to 135 format full frame) but the moon still doesn't get anywhere near filling the frame.



        This was under-exposed by almost 2 stops, unfortunately, and although PP has improved it the detail is not very good if you crop more closely.



        I will have another go in due course

        Ian
        Founder/editor
        Digital Photography Now (DPNow.com)
        Twitter: www.twitter.com/ian_burley
        Flickr: www.flickr.com/photos/dpnow/
        Pinterest: www.pinterest.com/ianburley/

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        • #5
          Re: bark at the.....

          the reason, i guess, i'm getting such extreme magnification is because i'm using eyepiece projection to a lensless slr rather than a compact. with the slr, the focal plane is quite a bit further back than where an eye would normally be. consequently, the camera is seeing a much smaller proportion of the projected image. this does pose a problem in that the field of view is always very small. to get wide field, i'll need to piggyback the camera to the scope and then shoot through whatever lens.

          the other problem thrown up is how critical the focussing is. my shots above are a little soft. the other problem i've got is the weight of the camera tugging on the ep mount & focus mech. this means that the top & bottom of the photos are blurred.

          that said, this is my first foray into photography through a scope, so it's all a learning curve. i'd mentally put off getting another scope, but i think an 8" will be on the cards soon...
          Last edited by devilgas; 14-03-11, 01:05 PM.
          Dave
          http://www.devilgas.com

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          • #6
            Re: bark at the.....

            I have learned from my experience so far - and I will up the ISO a bit to force a faster shutter speed as even with my big Manfrotto 058 tripod and 029 Mark II head, everything wobbles visibly and the moon itself races across the frame (I don't have the luxury of motorised tracking!). And of course I will get the exposure right

            Ian
            Founder/editor
            Digital Photography Now (DPNow.com)
            Twitter: www.twitter.com/ian_burley
            Flickr: www.flickr.com/photos/dpnow/
            Pinterest: www.pinterest.com/ianburley/

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            • #7
              Re: bark at the.....

              the motorised tracking made a huge difference. it made getting yesterday's sun and moon shots that much easier. it's still a bit of a faff as i don't have the luxury of 8x forward & backward speeds, so therefore need to disconnect it (a few secs with a screwdriver), get my target lined up + a bit extra, then re-connect it. the bit extra allows for re-connect time. i can then switch the motor back on when my target is centralised. it's then just a case of fine tuning the speed control to get zero drift.

              motorised tracking won't work on a normal tripod as it cannot account for rotation etc. a normal tripod works in alt/az (x&y basically).
              the mount on my scope is something called an equatorial mount. you align it to the celestial sphere by zeroing the scope and aligning with the north star. then the 2nd set of axis work as alt/az (names get changed to right ascension and declination) but aligned in relation to the celestial sphere rather than the earth. ** note ** this is my cr*p description rather than a textbook reproduction

              when correctly set, the motor is attached to the RA which then moves the scope in such a way that the object is tracked AND the tube is rotated to keep the stars in the same plane.
              Dave
              http://www.devilgas.com

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              • #8
                Re: bark at the.....

                Originally posted by Goatsmilkuk View Post
                Can you run your motor off a 12v car socket? Reason I ask is that I run my scope off a 12v power pack the type you jump start a car with, it also has a couple of sockets on it which I plug into. runs the scope all night and more.

                I will post some shots of it along with my poor attempt at M42

                Stu
                remembered i had one of those 12v power pack thingies that will output at various voltages. dug it out and it's on charge. a small mod to the RA drive to fit a jack and should be job done
                Dave
                http://www.devilgas.com

                Comment


                • #9
                  Re: bark at the.....

                  Originally posted by devilgas View Post
                  remembered i had one of those 12v power pack thingies that will output at various voltages. dug it out and it's on charge. a small mod to the RA drive to fit a jack and should be job done
                  ...that's good as I'm looking forward to seeing more (please).

                  Regards. Barr1e

                  Comment


                  • #10
                    Re: bark at the.....

                    Originally posted by Barr1e View Post
                    ...that's good as I'm looking forward to seeing more (please).

                    Regards. Barr1e
                    tried to get out last night, but by the time i'd uploaded the weekends games to my www and sent stuff to the press, the clouds had started to appear and got progressively thicker.

                    the law of sod was proven yet again.
                    Dave
                    http://www.devilgas.com

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                    • #11
                      Re: bark at the.....

                      had a pop at the orion nebula (M42) earlier this evening. full moon made the conditions a bit more difficult, but finally managed to get something semi-recognisible. it's not going to win any awards, nor stand up to other images of M42.....



                      2No. 20s exposures at 1250 ISO, 'stacked'. what you're seeing is the heart of the nebula.

                      i need to be able to stack quite a few more images to bring out the detail that sits to the left and right of the image. i took a load of photos last night, but any movement on the scope from the breeze killed those images. still, it's a starting point
                      Last edited by devilgas; 19-03-11, 11:08 AM.
                      Dave
                      http://www.devilgas.com

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                      • #12
                        Re: bark at the.....

                        did some shots of the moon, but with it being very nearly full moon at time of shooting, they look very flat. i much prefer it with side illumination, as per the first shots, as it shows much more texture & detail.
                        Dave
                        http://www.devilgas.com

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                        • #13
                          Re: bark at the.....

                          Great shots dave, Ive enjoyed looking at your recent work of the outer world. Ive taken some shots tonight of the moon as it was really clear with a nikon 80-200 2.8, struggling for reach but im happy with the results.
                          Ash
                          http://www.ftmphotography.co.uk

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                          • #14
                            Re: bark at the.....

                            thanks ash.

                            having now got 'how to shoot through a scope' sorted i've actually got more reach than i thought would be possible, the advantage being that i can get some impressive levels of detail (when the focus is right).

                            this was one shot from last night. chosen as it reveals some crater detail - that's where my attention lies with the moon....



                            again, the edges are fuzzy due to the camera stressing the focusser. i'm going to have to find a way to relieve the weight of the slr somehow. might be a job for later this morning. frankenscope will be born!
                            Dave
                            http://www.devilgas.com

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                            • #15
                              Re: bark at the.....

                              There was someone on here a few months back asking for advice on digiscoping, cant remember who it was. I wouldnt mind giving it a go myself.

                              This is my attempt from last night, heavily cropped but about as good as Im going to get with an 80-200 I think.

                              http://www.ftmphotography.co.uk

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