Roy@Aldermaston Posted June 20, 2011 Share Posted June 20, 2011 I've just bought an Antares X0.5 focal reducer to use between my LX modded SP900 NC and the SW 200 PDS, but its impossible to get enough inward focus. Has anyone found a solution to this problem that doesn't involve moving mirrors, or similarly drastic measures.Roy Link to comment Share on other sites More sharing options...
The Sailor Posted June 20, 2011 Share Posted June 20, 2011 A diagonal? I have had this problem and has helped me.Jim Link to comment Share on other sites More sharing options...
Roy@Aldermaston Posted June 20, 2011 Author Share Posted June 20, 2011 Jim,I'm probably being a bit thick, but how will that work with a 200PDS?Roy Link to comment Share on other sites More sharing options...
The Sailor Posted June 20, 2011 Share Posted June 20, 2011 Have I jumped in too quick , sorry Roy. I use a diagonal on both my SW refractors as I cannot reach focus without.Jim Link to comment Share on other sites More sharing options...
astro mick Posted June 20, 2011 Share Posted June 20, 2011 Hi Roy.I dont know how much inward travel you would need to attain focus,but an option(Although a little pricy) would be to change the Focusser to a Low Profile one.Several companies including Rother Valley Optics sell them.If you want to go down this route,i would discuss it with them as to suitabilty.Other than that its moving the primary further up the tube.Regards.Mick. Link to comment Share on other sites More sharing options...
Roy@Aldermaston Posted June 21, 2011 Author Share Posted June 21, 2011 Hello Mick,Moving the mirror is the one thing that I wanted to avoid, but there may be an easier albeit more expensive way to solve this.RVO sell these (http://www.rothervalleyoptics.co.uk/2in ... d2911.html) and used with one of these (http://www.teleskop-express.de/shop/pro ... wtons.html) it may be possible to increase the inward travel enough to reach focus - I hope. If you have the time to look at the links let me know what you think.Roy Link to comment Share on other sites More sharing options...
astro mick Posted June 21, 2011 Share Posted June 21, 2011 Hi Roy.Unfortunately the links dont work,so i dont know what your looking at.If you want to try again,or tell me what they are i will try and find them.Mick. Link to comment Share on other sites More sharing options...
Roy@Aldermaston Posted June 21, 2011 Author Share Posted June 21, 2011 Sorry for the duff links Mick, but in any case I've decided that this might do the trick for fewer pennies. TS-Optics 2" to 1.25" telescope adaptor, 1.25" reducer: Amazon.co.uk: ElectronicsI've checked the link and it seems to work.In the meantime I've come across a work-around which involves unscrewing the 1.25" barrel from the 2" threaded adapter and refitting it the other way round, so that it extends into the focuser rather than extending outwards. The only disadvantage is that the thumb screws on the 1.25" barrel can't be used to secure the camera nose piece, so I'll need a cable tie to stop the camera from flopping around, but it will do as a stop-gap.I'll try it out tonight.Roy Link to comment Share on other sites More sharing options...
astro mick Posted June 21, 2011 Share Posted June 21, 2011 Hi Roy.That adaptor may work a treat,and as you say for little money.I dont quite follow your interim fix,but if it works,great.Let me know how you get on.Mick. Link to comment Share on other sites More sharing options...
Roy@Aldermaston Posted June 22, 2011 Author Share Posted June 22, 2011 The trick to get more inward focus travel worked perfectly with the SP900NC and X0.5 reducer. Plenty of travel in both directions. My description of the mod was too confusing so I've added a PDF file with pictures. I can't take credit for the method and pictures, which were posted on another site. I don't remember who first came up with the idea, but I'm very grateful and hopefully the author won't object to my posting it here.RoySkywatcher Inward Travel Mod.pdf Link to comment Share on other sites More sharing options...
jnc71106 Posted June 22, 2011 Share Posted June 22, 2011 how about using a barlow with the webcam as this moves the focus point out thus enabling you to get focus thats what most people use myself included when there isnt enough inward traveljake Link to comment Share on other sites More sharing options...
Roy@Aldermaston Posted June 22, 2011 Author Share Posted June 22, 2011 Thanks Jake,What I was was trying to do by using the focal reducer was get a slightly larger field of view, partly to make it easier to frame the object. The method that I described was only a temporary fix while I am waiting for a low-profile 2" to 1.25" adapter to arrive.Roy Link to comment Share on other sites More sharing options...
jnc71106 Posted June 22, 2011 Share Posted June 22, 2011 Ah yes should have read the first post a bit better Jake Link to comment Share on other sites More sharing options...
Roy@Aldermaston Posted June 22, 2011 Author Share Posted June 22, 2011 How clear are the skies around Basingstoke, we get a lot of LP from Newbury, Reading and AWE.Roy Link to comment Share on other sites More sharing options...
jnc71106 Posted June 22, 2011 Share Posted June 22, 2011 How clear are the skies around Basingstoke, we get a lot of LP from Newbury, Reading and AWE.RoyFrom my garden north is not great because of the town centre. Can barely make out Polaris most nights but it's not to bad overall really Tried to convince the OH to move to sark but she won't have it Link to comment Share on other sites More sharing options...
Roy@Aldermaston Posted June 22, 2011 Author Share Posted June 22, 2011 Sounds good, keep trying Link to comment Share on other sites More sharing options...
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