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Everything posted by Lonestar70

  1. It is just possible your 9mm eyepiece may be a Russian origin 32mm dia not a true 1 1/4". A Barlow lens will move the focus point a good bit further out of the focuser, so you would need to bring the draw tube much further out to find focus. Seeing and air turbulance can often make focussing tricky at times, especially at higher magnifications, even with the high quality eyepieces. Keep practicing and it will all come together in time. Good luck and clear skies. Sandy.
  2. Hi Ray, This should do all you need... Use the shield for the -ve. http://www.maplin.co.uk/p/audiovisual-twin-screened-two-core-grey-priced-per-metre-xr20w Hope this helps. Sandy.
  3. Hi Simon, You say you have recently updated to Windows 10... have you also updated your Nikon NX/transfer software... I think you need to now use the lates version NX2/Transfer 2... and possibly latest camera drivers for W10. I believe your problem may be that the EXIF data embeded in your Raw images is unreadable, or being corrupted somehow if using the original NX/transfer software. You should be able to download the update files direct from the Nikon website for free (you may need to input your camera serial number). I use a Nikon D90 and I had a similar problem when I changed from XP 32bit to W7 64bit. http://downloadcenter.nikonimglib.com/en/products/22/D5000.html DSS won't load or recognise any files which have damaged/corrupt exif data. I hope you get it all solved soon. Best regards. Sandy.
  4. Hi Patrick, Superb images and a wonderful tribute to your late father... I am sure he is looking down with an approving eye and saying to himself 'I did it right'. I hope your move goes well for you. Best regards. Sandy.
  5. Hi PM, Not sure, but it looks like you may have a male to female (possibly T-2) conversion ring fitted. If you look at your cross sectional drawing (a few posts above) this clearly shows a Female thread inside the adaptor (the side opposite the thumb wheels on the casing) for the telescope connection (bottom side of the drawing).... which extends to the inside face of the casing. Hopefully you will get some confirmation from Altair. Keep happy. Sandy.
  6. It looks to me like the inner bearing has collapsed, or has worn away, inside the top of the mount. If you unscrew the silver star bolt far enough you should be able to lift the yolk out of the tripod, but you may find the bearing has cold welded it'self to the spindle. The silver star bolt should just be a locking screw to prevent rotation, however the inner end may sit in a recess in the yolk spindle to prevent it falling out. It can possibly be fixed with a new bush/bearing. Best regards. Sandy.
  7. PM, I think you will find the SX adaptors all maintain the 29mm thickness but you can email Altair Astro to double check. Don't forget to order the FEMALE thread version to take the MALE SW Coma Corrector thread. http://www.altairastro.com/starlight-xpress-male-m48-face-plate-for-sx-filter-wheels-starlight-xpress-t2-face-plate-for-sx-filter-wheels-choose-male-or-female.html This would result in 29mm +17.5mm = 46.5mm... so you would need to add 8.5mm on the camera side... not the best option really since you need to keep the filters as close to the camera as possible to avoid vignetting issues. Perhaps a better solution would be to get the Male thread version of the SX adaptor and locate a short 8.5mm all Female M48 x 0.75mm extension tube which could then be fitted between the Coma Corrector and the SX adaptor. I believe TS (Teleskop services) may have a suitable extension tube. Note... the above does not take account of the effect the filters have on the optical path length of the filter wheel but I seem to remember this increases the optical length of the filter wheel assembly by something like 0.7 x thickness of the filter, therefore the 29mm physical length would be increased by this amount which will reduce the length of the required extra extension by the same amount. Hope you get sorted. Best regards. Sandy.
  8. Hi PM, You may struggle with this I am afraid but it depends on what adaptors you may have for the scope-side of your filter wheel. The backfocus distance for the SW Coma Corrector is 55mm and with the full format sensor of the SBIG this will need to be within +/- 0.5mm. This distance is measured from the bottom of the thread on the back of the Coma Corrector to the sensor plane. The thread on the Coma Corrector is M48 x 0.75mm. I believe the standard Starlight filter wheel is 33mm front to back including the normal adaptors... so you don't have much to play with. Ask FLO if a suitable scope side filter wheel fitting is available with an M48 x 0.75mm internal thread which could replace the standard fitting... if such is available then the Coma Corrector can be screwed directly to the filter wheel and will minimise the optical path length of the fiter wheel assembly... if not available then you will need a converter adaptor the thickness of which will need to be added to the filter wheel thickness when calculating the spacing. I am not aware of the body-sensor depth of the SBIG... possibly around 19mm so you won't have very much lee way. I wish you luck in getting set up. Best regards. Sandy.
  9. Lonestar70

    Newbie stargazer

    Hi Sagan and welcome to SGL. Hopefully you will get a lucky break in the cloud cover and get to see some great sights in the night sky. Try and find a nice sheltered, but safe, location as far away from Colchesters light pollution, you will be surprised how much difference it will make. Good luck and clear skies. Sandy.
  10. How about using a sheet of black art card available from most good craft shops in various thicknesses... cut an 8" hole in the right place and you could also add a ring, made from a strip or 2 of the same material about 1" wide, to slip over the OTA... easy to do, not overly expensive and simple to work with... also totally light proof. Would fit directly into your frame if you use A3 size card. A couple of coats of clear matt varnish or laquer on the outside will give protection from atmospheric pollution and damp. Good luck and clear skies. Sandy.
  11. Hi Gina, Have you seen this it is quite something. http://www.ted.com/talks/joe_desimone_what_if_3d_printing_was_25x_faster Looks like things are going to change rapidly in the 3D printing field. Keep Happy. Sandy.
  12. Lonestar70

    Mr Cat

    Hi MrCat, Welcome to SGL. Nice find and should get you started on the slippery road of astronomy where being slightly mad is a great asset... you have joined the right crowd. Where are you located in Argyll? I am near Lochgilphead and would be happy to assist if you need any help. Clear Skies. Sandy.
  13. Hi Rico, You may be able to recover the lost files as follows: - I deleted files from my recycle bin, i need to recover them, how can i do this? You may be able to recover the deleted files using the Previous Versions component. 1. Open Windows Explorer and navigate to the folder where the original files were stored. 2. Right click the folder and select the Restore Previous Version from the menu. 3. In the Previous Version dialog, select a version with a date and time prior to when you deleted the files. 4. Select the Copy Button. Select the Desktop as the location for the copy and click the Copy Button. 5. Go to the Desktop, open the copied folder and look for the files. If the files are there, move them out of the copied folder to the Desktop. You can then delete the copied, previous version of that folder. Certainly worth a try. Hope this helps. Sandy.
  14. 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.
  15. 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.
  16. 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.
  17. 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.
  18. 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.
  19. 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.
  20. 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
  21. 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.
  22. 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.
  23. 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.
  24. 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.
  25. 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.
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