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Lonestar70

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Everything posted by Lonestar70

  1. Hi Martin, Yes, I agree... cigarette connectors are very unreliable. I second the use of the 3pin (or more) XLR connectors... I use them for most of my power and data cables. As Chris has stated... the Anderson Powerpole connectors are also a great option and can be stacked to form multipole connectors if required... they are used a great deal for Radio controlled models (electric flight etc) and also for amateur radio. They are readily available in the Uk from the following: - http://www.mardave.co.uk http://www.northern-connectors.co.uk http://www.amazon.co.uk/Power-Pole-Connector-Black-Anderson-Sermos/... http://www.torberry.co.uk/powerpoles.php They are also available from various ebay suppliers. Hope this helps. Best regards. Sandy.
  2. Hi Riggy, I also use a Nikon DSLR and have found that mirror vibration is, for all intents and purposes, not a problem. As with most modern DSLR's the mirror mechanism is a very gentle affair... so don't worry about it. As for a dew shield... if you already have the standard Nikon flower petal type lens hood fitted then all you need is a cardboard tube (preferably black on the inside) that fits snuggly over the shield... make it so that it extends about 1 1/2" - 2" past the outer end of the lens hood. It does not really need to be insulated, but it would do no harm to cover the outside of it with some dark material (thin foam or velvet cloth). A couple of other points: - Shoot your frames in RAW mode... JPG is far too lossy and can also introduce conversion noise. Turn OFF in camera long exposure noise reduction. If you are using a high ISO (above 800) then also turn OFF high ISO noise reduction. Take some DARK exposures at exactly the same settings, and focus, as for your LIGHTs... and use them when you stack your images to eliminate/remove any noise. DISABLE the on camera flash. Cover the viewfinder (use the small black viewfinder cover supplied with the camera to prevent any light entering through it). After you have focused... Turn OFF Live view... and, as has already been stated, the auto preview of the pictures. These features will (a) cause the sensor to heat up and ( will use up battery capacity. I will second the recommendation for using a programmable electronic timer release... it certainly makes life a lot easier, and will ensure that all your exposures are exactly the same length... not always so easy with a manual release. One of the important things to remember is... leaving a delay between each exposure (a. to let the sensor cool down) and (b. to allow sufficient time for the transfer of the taken image to the memory card)... the programmable timer release can accomodate this very easily. I think that about covers most things you need to know... so HAPPY SHOOTING and let us know how you get on. Best regards. Sandy.
  3. Welcome to SGL Alan, There are a few clubs in Essex which you could look at, I am sure one, or more, would be within striking distance. Perhaps the members at one of them would help you with your scope and suggest how to get the best from it... it may only require a better eyepiece to improve your viewing. Castle Point Astronomy Club Clacton & District Astronomical Association Havering Astronomical Society Loughton Astronomical Society North Essex Astronomical Society (NEAS) Thurrock Astronomical Society I hope you find a suitable one from this list. Best regards and clear skies.
  4. Hi guy's, Not sure I totally agree with your last statements Neil. volatile long NoOfSteps = 1000; //required number of steps to make volatile long Position = 0; //used to keep track of the current motorposition volatile long MaxStep = 200000; //define maximum no. of steps, max travel volatile int SPEED = 500; Surely these 4 Variables can be changed outside the programme by e.g. the stand alone focuser test interface. And, presumably, any other interface using the ASCOM driver. Whilst the values assigned by the above declarations are a good basic starting point, not all focussers would use the same values. (mine certainly does not) The whole point of declaring them as volotile prevents the compiler from optimising them out or doing some other dastardly thing with them (as they often do) just to make the code more compact. I agree that the others could be made non-volatile since they are only ever assigned a final value by the programme once. Please correct me if I am wrong in this thinking. Best regards.
  5. Strictly speaking... the 2 scopes you show links to are not the same OD The first one is an 8" scope and the second is a 6" scope which will have markedly different tube OD's. Both sizes of scope are available on either type of mount so yes, in order to mount the DOB version of each size on an EQ mount then your last assumption regarding the correct tube ring size is correct... you would also need a suitable Dovetail bar. Best regards
  6. I forgot to add that the other advantage of using the FLO nosepiece is that you can easily rotate your camera for framing... not so easy with the FF/FR directly screwed in place. Best regards. Sandy.
  7. Hi Amajed, Yes it screws directly to the focusser tube when you unscrew the standard 2" eyepiece holder, however this makes using any additional filters tricky (other than the clip in versions for canon camera's. What I do is leave the standard 2" eyepiece holder (standard fitting on the draw tube) attached, and use a 2" nose piece (available from FLO for use with this FF/FR) which has the facility for screw in 2" filters. The whole FF/FR + t-ring and camera then become a single assembly... just like a normal 2" eyepiece. Best regards.
  8. Hi Amajed, The correct FF/FR for your scope would be the SW 0.85... it has been optimised for that scope. The SW 0.85 FF/FR and the corect M48 - T adaptor for your camera are currently available from http://www.harrisontelescopes.co.uk/acatalog/Focal_Reducers.html Both are showing as in stock and just as FLO they are a trusted company to deal with. You will not require any additional extenders for this combination. Hope this is of help. Best regards. Sandy.
  9. Hi Sam, Ok, that explains a lot... I have just been looking at the manual for your scope and it would appear that the 2" extension is required to achieve focus when using standard eyepieces... so you may find you have to re-fit it when you dont use the barlow. It also appears that the focuser is a low profile unit which is good for achieving focus (prime) with a DSLR camera. It clearly states that the extension should be removed and the t-ring directly attached to the focusser tube. The Meade #140 barlow,Quite a long looking afair, is also shown in the manual, and seems to have the extension built in so again the normal extension would need to be removed. Seems a very strange way of arranging the optics though... but Meade tend to do strange things at times. Anyway, you have got it sorted for the time being. That just leaves the tube rotation to sort out and you will be away and running. Have fun. Best regards.
  10. Hi Sam, A barlow lens will/should make the focal point further out from the focusser so would require greater OUTWARD travel to bring an eyepiece, or camera, to focus. Have you tried focussing over the full range of focusser travel?... go slowly, as it's quite easy to miss the correct position. As for modifying your tube to allow front end rotation... NOT a good idea as it would certainly play havoc with collimation. The normal course would be to slacken both the tube rings and rotate the whole OTA to bring the eyepiece to a more suitable position for viewing, then tighten the rings again. A third ring fitted to the OTA just above and just touching the top ring but not attached to the dovetail bar will prevent the whole OTA slipping down when adjusting the orientation. Do a search for "rotation ring" on the forum... there have been several posts showing how these can be easily made and fitted. Hope this helps. Best Regards.
  11. Hi Whistlebare, Don't fret about it... a lot of us (including me) made the same mistakes when we first started. I find it a lot easier to polar align the mount without the scope attached... the mount can get into some very wierd positions sometimes in order to get the polar circle in the right place and this would often mean the scope would hit the mount if it were attached... I have to set up every time, since I don't have a fixed pier... once polar aligned I return the mount to the Home position and fit the scope and balance it... returning to the home position again before starting star alignment. You have the luxury of a fixed pier so once you have got it polar aligned you would only need to check it from time to time. (nice pier by the way). Anyway, glad you got it sorted. I am a good bit further up the west coast to you... near Lochgilphead.... lovely dark skies though... WHEN IT STOPS RAINING that is... Keep happy. Best regards.
  12. Hi, You need to return the scope and mount to the Home position (weights down and scope pointing towards polaris) before you attempt star alignment. The mount makes the assumption that this is the position it is starting from before slewing to the first alignment star. If, as it would seem you are doing, you leave the scope and mount in the position you had it for Polar alignment then the mount just assumes it is in the Home position and you end up with it slewing into the mount. Hope this helps. Best regards.
  13. Hi Alex, The correct coma corrector for the SW200P is this one Skywatcher 0.9x Coma Corrector You will also require the M48 camera adaptor for the Nikon. Skywatcher DSLR-M48 Ring Adapter Both are available from FLO. It is arguable whether you can reach focus with the standard 200p focuser, as you may find that it has insufficient inward travel. especially since the coma corrector also works as a focal reducer (0.9x)... this will make the focus point somewhat closer to the scope. (opposite effect of using a Barlow) You could certainly find focus using a Barlow inserted into the focuser and with the coma corrector fitted into this, however the net result would be a much longer focal length (not recommended). The only other method would involve moving the main mirror cell up the OTA tube to bring it a little closer to the secondary... this will move the focus point further out on the focuser. This may not be a good option since it may effect the warranty on a new scope. If you have not already got the 200P (reference your question in another thread) then you would be better off saving a little more and going for the SW200P DS since this has been modified for DSLR photography and will certainly reach focus without the Barlow. It also has the low profile dual speed x 10 focuser fitted, which will be much better for fine focussing. I hope this answers you question. Best regards,
  14. Hi Mike, You can obtain 1/4" x 20 BSW studding, dome nuts and standard hex nuts all in stainless steel from: - http://www.stainlessautomotivefastenings.co.uk Cut the studding to length required and fit a DOME nut on one end (use a touch of araldite or loctite if you want it to remain fixed) this will replace the round head... then you can use a standard nut for adjustment/driving purposes if required. Stainless steel will be better suited to outdoor work in the cold and damp. Finding off the shelf round head bolts at 1/4" x 20 whitworth is no longer that easy... especially 4" ones... thanks to metrication. Hope this helps. best regards. Sandy.
  15. Hi Gina, Thank you for the + vote on the sliding weight idea. That would be my main fear also... especially in the dark when you cannot see the clamp positioning clearly. It's not the best clamp arrangement at the best of times.. and anyway, you have had enough heart stopping mishaps... you certainly don't need any more. I will see what I can come up with and will post the results. Probably best if I do that in the DIY section. In the words of Cptn. Oates... " I may be some time" If it works out ok and you think it would suit your set-up then I am sure I could be persuaded to make a second set. Us oldies have got to stick together you know!! :grin: Keep happy and healthy.
  16. Hi Gina, it’s so nice to finally make your acquaintance. I have been following your many exploits/projects, trials and tribulations, successes and, sadly, the occasional misfortune for some time prior to joining the lounge. They have certainly given me the incentive to get my act together and sort out a decent set-up for myself… albeit; I am unable to install an observatory. I already have a large (engineering) workshop and there is just not the room (or damagement approval) to add yet another large home for my hobbies. Orion! ... Oh yes…! …I vaguely remember him… he’s the one with the flashy sword and a bow and arrow being chased around by a couple of dogs and a unicorn whilst annoying an old bull isn’t he? Last seen up here in 1812 December 2012 due to the rubbish weather. It would be nice just to catch a glimpse of a star now and then, let alone a whole constellation…and for a whole hour … I jest of course. All we’ve had here since December is Clouds, rain, snow, howling gales, more rain… did I mention clouds? Ho hum!! Returning to the balancing issue… Yes, finding a system that suits changing the various capture equipment, more often than not having vastly different weights, is not so easy to achieve is it? … Especially when the basic ED 80 is already focuser heavy when mounted at the back of the dovetail. My current arrangement (similar to that used by Sara), being a fixed weight, is fine for my current DSLR camera set-up… but is not really flexible enough to accommodate the large changes in weight distribution if I choose (seriously being considered) to go down a similar route to you. I have already stated, my concerns with the use of longer dovetail bar with regard to bending point… and, whilst not entirely ruling it out, my current thought is to fabricate some sort of sliding weight counter balance arrangement mounted on the back of the objective end of the dovetail bar. This, hopefully, will permit, reasonably simple, re-balancing when a camera change is made, or other attachment is added, without the need to unclamp the main dovetail bar at the mount… always a risky operation in the dark… and cold. Decisions, decisions… !!!! Methinks it is time to get down to the workshop, crank up the lathe and milling machine and coble something together… Now where did I put that lump of unobtainium?? What other ideas do you have Gina? Best regards.
  17. Hi Martin, Thanks for your thoughts... Yes I did consider using a longer dovtail bar, as you say it doesn't matter which way up the scope is... my main concern with this method was that is got in the way of the camera (DSLR) possibly preventing it being turned to frame the shot and the fact that the balance point would mean having BOTH tube rings forward of the attachment point to the mount... thus creating a single bending point at the mount attachment closest to the first tube ring... possibly leading to flexture since the back end of the dovetail bar would not be attached to anything behind the attachment point. By clamping between the tube rings this is avoided... as the 2 tube ring attachments work in opposition too each other... if you see what I mean. Perhaps I am being to critical/analytical in thinking this...Too much engineering training in my youth methinks... Maybe I will give it a try and see what happens. I take your point about there not being an UP in space... does it also follow that there is no DOWN... Not sure NASA would agree with us though... they would never get any of their rockets back :grin: Cheers and clear skies
  18. Hi Ed, You should only need a t-ring for your D60 like this: - http://www.firstlightoptics.com/adaptors/t-rings.html Just pick the one for Nikon and you should be in business... It is the one I use for my D90 on a 2" SW focuser. Cheers
  19. Hi there, The 8" dobsonian is a great scope for a beginner to learn their way around the sky, however, if, as you say, you wish to get into astrophotography, at some point in the future, then I also would strongly recommend getting a copy of 'Making every photon count'. It was written by a fellow SGL member... 'Steve Richards'... (AKA Steppenwolfe) and is worth it's weight in gold when it comes to purchasing the correct equipment... and more importantly not buying something not suitable. Astrophotography is a whole new ball game when it comes to equipment and I agree that the HEQ5 Pro mount would be the very minimum you should consider but, as stated above, even this would struggle with an 8" scope... for this you would certainly need to go for the NEQ6. You may be lucky and find one second hand... but don't hold your breath... and keep saving up. Where abouts are you in Western Scotland?... it would be nice to have a fellow stargazer to meet up with. All the best and clear skies.
  20. No problem John, you are most welcome. I should point out that I mis-quoted one of the dimensions (just a TAD) They should have read 70cm long x 18cm dia... ( 80cm indeed)... must be getting old. Have fun and enjoy.
  21. Good evening Sara, Thank you for your valued input ... it would seem that we both have come to the same conclusion. I am not too worried about the additional weight since, as you say, the total package is well within the limits for the mount... it just looks somewhat odd/untidy and I just wondered if perhaps a better solution could be achieved... but hey' if it gets the job done then thats what counts I suppose. I have seen some of the images you have posted on this forum, and if they came from the setup pictured above then they are a standard for me to aim for. Now... if only the grey skies, rain, snow, howling winds and yet more cloud would remove themselves from the scene, perhaps some of us here in the UK could get out and do something. Thanks again Sara, Clear skies to you.
  22. Hi Ruthie, welcome to SGL. The only silly question is the one you don't ask. We all start at the first rung and then spend the rest of our time in this life asking questions... they never stop. Just ask away. Clear Skies. Sandy.
  23. Welcome to SGL Steve. Lots of very talented people on here and they are very helpfull with advice on all things astro. Clear Skies. Sandy.
  24. Hi Gio and welcome to SGL. Another + here for the suggested items, however, you can't steal the book from the library... cos I came over on the ferry and got it first!!!!! Clear skies. Sandy.
  25. Welcome to SGL JAMCART. Another +1 for Steve Richards' book It certainly helped me to make my final choices. Best Regards and clear skies. Sandy.
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