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Lonestar70

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Everything posted by Lonestar70

  1. Hi Andrew, Welcome to SGL. These are what you are looking for: - T-ring adaptor: - http://www.firstlightoptics.com/adapters/t-rings.html The last one on the list. or: - http://www.365astronomy.com/T-Ring-for-SONY-Alpha-Nex-and-E-Mount-Cameras-T2-Lens-Adapter-Ring.html You may also need a 1 1/4" / T-2 Male nosepiece if your scope does not have a t-2 thread on it's focuser tube: - http://www.firstlightoptics.com/adapters/flo-125-inch-t-mount-camera-adapter.html or: - https://www.harrisontelescopes.co.uk/acatalog/T_Adaptor_1.25_.html I think you will be limited to 30 second exposure as I dont believe the nex-5 has bulb mode for longer exposures. I am not sure if it has a timer system with capability for multiple exposures, I suspect it doesn't. What telescope and mount are you going to be using? Hope this helps. Best regards. Sandy.
  2. Try Google maps... they have a co-ordinates finder which should give Lat, Long and elevation. alternatively most GPS apps will give you these. Just put your street name and postcode in and it will return all 3 co-ordinates. Gateshead varies between 5 and about 165 metres depending on precise location. Good luck and clear skies. Sandy.
  3. Hi, Don't use the generic driver that Windows loads by default when you plug the cable in, it causes most of the problems you describe... go to the Hitec website and download the correct Prolific driver for your device... then replace the Windows driver with this in Device Manager. 3rd item down on this page: - http://www.hitecastro.co.uk/index.php?option=com_content&view=article&id=51&Itemid=55 This is for the early versions of the EQDir unit. If you have the latest version then you need the driver at the bottom of this page: - http://www.hitecastro.co.uk/index.php?option=com_content&view=article&id=49:eqdir-adaptor&catid=37:eqdir-adaptor&Itemid=54 It is advisable to have the latest version of EQASCOM installed before installing any drivers. I hope this helps. Sandy.
  4. An alternative MAC driver source is here: - https://www.mac-usb-serial.com/ It may be a better source even if the driver version is the same, some download sites can be corrupted or damaged in some way, so It could be worth installing from here... delete the existing driver first. You may need to set the Baud Rate and Data bit pattern to suit Stellarium before you can get control... check the Stellarium help files. Sandy.
  5. Hi Essex person... from an ex-Essex person. Here is a direct link for EQMAC : - http://eqmac.hulse.id.au/ I don't use it myself so can't vouch for how well it works... I use EQMOD which is the original Windows version. When using this type of connection under EQMOD you would need to place the handset in PC-DIRECT mode... I don't know if the same applies under EQMAC. Which software are you using to control your scope with? You may be better off installing windows on a virtual drive and using EQMOD and the ASCOM platform since most astro software supports this. Good luck and clear skies. Sandy.
  6. That is becouse the 2 versions are by different people. The original, and best, is by Dr Jason Dale http://myastroimages.com/Polar_FinderScope_by_Jason_Dale/ The NEW Version you have is by Jean Meeus and I agree it is not so easy to use. Keep Happy. Best regards. Sandy.
  7. Hi, 4.5mm tracks in 1oz copper will handle 7amps continuous with a 10deg C track temp rise... at 10 amps the track temp rise would be approx 22deg C. Voltage drop in the track will be 0.02v/inch @7amp... 0.03v/inch@10amp. Assuming the 10amp usage is at peak loading (short term) then you should be OK. Good luck with your power pack build. Best regards. Sandy
  8. Hi, The screw terminals may be rated for 16A, however you will need to use track a width of at least 7.38mm in 1 oz copper at 10Amp... with a track clearance of 0.66mm. For 2 oz copper the track width will need to be 3.69mm with the same track clearance. These figures are based on a max track temperature rise of 10deg C (in Air) and a maximum applied voltage of 14v DC. (A fully charged battery is approx 13.8V). I hope this helps. Best regards. Sandy.
  9. Hi Malcolm, I think that is conclusive proof that the problem is nothing to do with your stepper drives or the 4:1 gearing, so you can tick those off the list. As for the return to a previous sync point... I am given to believe that the calculated error applied at a sync is not a constant, but rather it changes with elapsed time and can also be influenced by the type of pointing model you are applying... I believe this is what Chris was alluding too a few post above. I am not familiar enough with celestial modelling to offer any meaningfull suggestions in this regard other than being aware that it becomes much more difficult to calculate when the meridian is crossed and a flip is initiated. I will let Chris deal with this particular aspect. At least you have made a couple of steps in the right direction by eliminating the steppers and gearing. I guess the next thing to get to grips with is ensuring the scope and mount are both pointing at the same celestial point. Whilst these sort of problems can be very frustrating when they occur, solving them can teach us a lot which might otherwise be missed. I shall be keeping a watch on your progress and hopefully learn along with you. Keep Happy. Sandy.
  10. Hi Chris and Malcolm, Well the above test results would appear to justify Chris' faith in open loop counters in this application, my apologies to you Chris for my doubts in this regards. It is quite clear from the values that there is no error of any significance in DEC and the small incremental differences in RA can be accounted for by the motion of the earth. This would suggest then that the large errors you are getting are not directly related to the stepper motors, but could they be due, somehow, to the 4:1 gear ratio handling in the software... especially since you appear to get different results with different versions of the same software. I have my doubts on this score though, since there have been a lot of mounts modified in the same way and this particular problem has not been raised as a significant issue as far as I know... regardless of software version... and I am sure Chris would have jumped on any such potential problems in short order and got it resolved. It would be interesting to see if the standard gearing produced the same errors on your mount Malcolm. I must say I don't get any such large errors with my own HEQ5 using the same software combinations as yourself but my mount has not had any drive modifications applied to it as yet... but I am considering it... if only to quieten the mount down a bit when slewing (albeit I would be using the standard gearing version). At the moment I am at a loss as to what to check next. Perhaps Chris can suggest something more to try. Best regards and I hope you find the problem. Sandy.
  11. Hi Malcolm, It would appear from the above that the positional error in RA is reasonably constant at around 2' 30" but your DEC error is between 18' 11" and 27' 39"... this would suggest 2 possible causes. It is possible that your Belt modification is either slipping somehow (belt or pulley) or maybe the belts are too tight, especially in the DEC motor... which could easily result in the motor missing pulses or lack of mount movement. Much as I admire Chris' faith in open loop systems, my 20+ years in designing stepper driven precision positioning systems for industry, where such errors could easily cost the customer several thousands of pounds, would contradict this... I have, on several occasions, witnessed steppers snapping backwards to the last stable detent position on receiving a full torque phase... meanwhile the counter has registered a full 16 microsteps... it does not take many such instances, and yes they can and do occur, to render the data held in the counters useless for further positioning... the only way to eliminate such problems was to utilise encoders. I accept that a hobby telescope mount is a different application and that any such error is more of an inconvenience (albeit very frustrating) rather than a potentially large financial loss, the fact still remains that such errors could account for at least some of the positioning errors we experience with our mounts. The later SW mounts, which do have proper encoders should be much less prone to this, since the encoders should at least ensure the counters contained the correct information. So I would first check your belt mod and make sure it is all aligned correctly, the belts are correctly tensioned and not over tightened and also the pulleys are firmly fixed to the motor spindles. The other thing to check for is CONE ERROR... it is quite possible that your scope and mount are pointing to different locations in the sky... a 2' 30" error is not a lot when referenced directly at the scope /mount attachment... this could effect both RA and DEC relative to the scopes polar axis. This sure is a strange one though and I suspect there is more than just one issue...all combining to produce the apparent problem/s. It is going to be a case of 1 thing changed at a time in order to correct things. I hope you can locate the error/s soon. Best regards. Sandy.
  12. Hi Guy's, Chris... Just a few thoughts... the above could surely only be achieved if the mount motors were fitted with true positional encoders... which the HEQ5, or HEQ6 do not have... they are open loop. In reality, on these mounts, the motor control board has no idea where the scope is actually pointing. The only positional info the motor control board, and any other control software would have available is the number of steps the motors have been issued with, and in which direction from a known start position. These current pulse counts could be out by a fair bit in reality as far as the actual position of the scope is concerned, since it cannot take into account any missed steps..i.e just becouse a number of steps has been issued does not mean the motors have actually made them, which is much more likely when microstepping is used (much lower step torque available) so even a small bit of extra drag could cause the motor to miss a step or more and the controller board or EQMOD would have no means of detecting this. The same would apply to any stored sync offset values since these may (for the same reason) also contain a false step count. Any calculations for a new slew position would therefore be starting from a possibly flawed values and the resulting slew target values would be out by the same amounts... furthermore, the resultant slew could quite easily add to the count errors for the same reason. Tracking could also be effected by this problem as well. The use of custom gearing could also influence this sort of error, but in which direction is open to conjecture since it will change the loading on the motors. I am thinking a lot of the goto accuracy issues are related to this lack of knowledge by the software of the actual true position of the scope. Of course, using different epochs in each software package would make matters worse. How do you feel this source of error could best be handled, other than installing true positional encoders. I can't think of any way EQMOD, ASCOM or any other software package could get round this particular problem. Keep happy. Sandy.
  13. Pulse guiding is an EQMOD function but you need to tell PHD to use it... not ST4 (in Camera)... and disconnect the ST4 cable. if EQMOD moves your scope in all directions then it should also work for Pulse Guiding. Are you connecting to EQMOD using the handset (in PC Direct Mode) or are you using an EQDIR module... for best results you need the latter as the handset mode adds a lot of unknown delays etc which could easily effect guiding. Hope you get it sorted. Sandy.
  14. What you see through your OTA eyepiece in the home position will be determined, to a large degree, by the field of view of your scope/eyepiece combination, the accuracy of your home position and if you have any cone error... you may, or more likely, won't see polaris. You certainly won't see anything remotely like the view through the polarscope since there is no optical connection between it and the main scope... and you won't see any sign of a polar circle... this is actually etched onto a graticule within the polarscope as an aid to alignment. The home position is meant as a starting reference point for the GOTO electronics it has no real world, or space, meaning. After polar aligning your mount put your main OTA/MOUNT back to the home position and then do a 2 or 3 star GOTO alignment... this should be more than adequate for visual use. Good luck and clear skies. Sandy.
  15. Hi Silios, The SW FF/FR is very tight when used with a large sensor camera. Typically it is 55mm +/- 0.5mm for a 35mm sensor... this distance must include any allowance/adjustments for filters etc. For camera's with small sensors (say around 6.5mm) then the allowance can be greater at around +/- 3mm max, since they don't see the extreme edge of field. At 56.5mm with your large sensor you will be well outside the limits and get the resulting field curvature. It looks like you need to loose 1mm somewhere in the spacing... perhaps thinner adaptors on the filter wheel. Hope this helps. Best regards. Sandy.
  16. Commonly known as a step drill... great for plastic boxes and for sheet metal and much safer than a standard twist drill, which can easily screw it'self into sheet metal if great care is not taken even when it is specially sharpened specifically for sheet material use. These don't have a spiral flute so they dont catch you out in that way. It is advisable though, regardless of which you use, to clamp the workpiece down to prevent any movement. They come in both Imperial and Metric step diameters with varying numbers of steps. That particular one goes from 4mm dia to 32mm dia in 2mm steps. Their only limitation is that the thickness of material being drilled must be no thicker than the individual step height. Clear skies. Sandy.
  17. The problem with shortening the draw tube on the 130PDS is that you can only safely take off around 10mm. If you take off more than this then the draw tube can disconnect from the guide bearings, which are widely spaced on this focuser... the same issue occurs with the 150PDS. This draw tube intrusion is more of a problem with both scopes when used for imaging in conjunction with the SW Coma corrector. For Imaging use with the SW Coma corrector it is better to move the primary mirror up a bit to move the focal plane further out of the focuser... but this will then require a short extension for eyepiece/visual use. Keep happy. Sandy.
  18. Hi Elliott, Welcome to the collective, You will need these 2 components for your scope/camera set up... T ring http://www.firstlightoptics.com/adapters/t-rings.html The first one on the list is the correct one for a Canon EOS dslr T adaptor 1 1/4" http://www.firstlightoptics.com/adapters/flo-125-inch-t-mount-camera-adapter.html This screws directly into the camera t ring. It sounds like you may have the wrong t-ring... it should have a 42mm thread not 52mm The t adaptor should just fit into your focuser draw tube (or barlow lens) in place of the usual eyepiece. Have you also got the tracking motors for your mount? Hope this helps. Sandy.
  19. Hi Kev, I can confirm it is a 5A x 1 1/4" quick blow fuse... just looked at mine. Best regards. Sandy.
  20. Hi Matthew, I am pleased to read you have made some improvements... well done, thats a good few steps in the right direction. The difference in airey rings on either side of focus could be caused by a slight rocking of the focuser draw tube. It would certainly pay you to check your focuser out and adjust the spindle alignment and tension... both could be slightly out which could cause a slight rocking as the drive is applied in opposite directions... especially if the tension is too little. It is not very difficult to do and these guides will help: - Adjusting_Crayford_focuser.pdf https://www.youtube.com/watch?v=ofOSAMlqZWw Keep up the good work, your almost there. Best regards. Sandy.
  21. Hi Jonathan, You will not do any damage to your mount using a 6v 4Ah SLA battery, just fit a suitable in line fuse in the feed cable, say 3.5amp or 5 amp and be absolutely sure you have the tip polarity correct. The mount will only draw the current it needs, regardless of the battery type and remember to recharge the battery after each use with a good quality charger. If you decide to change to D cell batteries then a set of 5 x 10,000mAh rechargable D cells (as shown in the link I posted) would give you a 6v 10Ah battery which should last a good few hours. Good luck and clear skies. Sandy.
  22. Well done 10 out of 10... you have already marked the problem as 'SOLVED' in your last post. Keep happy. Sandy.
  23. Hi Pip, It would seem you are missing the lens profile updates in your camera. I know Nikon have had a few issues with this option on several of their cameras, including the D3200. Try this update: - http://www.thephoblographer.com/2013/07/18/nikon-updates-distortion-control-profiles-on-many-of-its-dslrs/ Hope this helps. Best regards. Sandy. EDIT: - It also appears that there is an update available for lens data in NX2. http://www.dpreview.com/articles/4729294719/nikon-updates-distortion-correction-data-for-dslrs-adding-latest-lenses
  24. Certainly worth a try it can only improve things by minimising reflections... not sure it will help much with the diffraction though. Moving the primary and blacking up may cure both problems with any luck. Keep Happy. Sandy.
  25. Hi Hadyn, You will almost certainly need an extension tube or you won't reach focus... the draw tube is just not long enough on the ED 80 to compensate for the focal distance lost when you remove the diagonal. I get away with a 50mm extension with my DSLR but you may need a little more for the X2 as it has a lot less depth from the front face to the sensor...My Nikon has 46.5 mm sensor depth but the X2 is around 17 - 19mm I believe. Clear skies. Sandy.
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