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Showing results for tags 'backlash'.
Found 6 results
joecoyle posted a topic in Imaging - Tips, Tricks and TechniquesHi I've set my scope up on it's pier in my ROR observatory, done a few drift aligns and started to take some images. I've noticed a 'quite' regular dip in my DEC line on several nights. Would anyone be able to have a quick scan of my log and offer any insight? Could it be backlash? Could it be something with each rotation of the gears? Faulty tooth? It is quite regular, although not always, and always in the same direction. It doesn't seem to be adversely affecting imaging yet, but I've not tried anything too taxing. Thanks Joe PHD2_GuideLog_2018-09-23_200940.txt
Hi all, Pretty often I read about people having issues that may be related to backlash in DEC or RA, and I would like to offer a very simple and effective cure for it. I have done it on my HEQ5 Pro but surely it can be modified for any mount that needs it. With this simple fix, I can live with a rather big backlash (with no risk for binding in freezing temperatures). For DEC, I always balance carefully (neither front nor back heavy). Then I stretch the coil spring until it has a small impact on the DEC balance (and later in the evening I eventually forget about loosening it when I slew away... so you will need some replacement springs. It took maybe 10+ of such mistakes until I stopped forgetting...). The bracket is only attached with double sided tape (on three sides), but the black maintenance plug (not original) also supports it. RA is usually OK with just the standard method "East Heavy", but occationally the scope is poing due west or east (counterweights pointing north) and then there is no "East Heavy" impact. That is when I use this: It´s a little hard to see in the pictures, but I get a momentum in RA (in reverse to tracking direction) when I tighten the string. Now, I happen to have the Rowan belt mod which includes a thick nylon spacer inside the gear cover, and that is a good thing here because it adds to the momentum. I usually hook it up an hour or two before the CW bar points due north. Then when it has well past north I will stop the camera, remove the backlash killer and re-adjust "East Heavy". EDIT: (Sorry, English is my second language...) Should be a torque, not momentum. Ragnar
kaito83 posted a topic in Discussions - MountsDear All! Please read everything!!! I have a big DEC backlash on my EQ3 mount near to 8000ms, and the pulse guide correction is slow and the 2000ms doesnt enough to correct this issue. So I decided to correct it with this great EQMOD project to add some new code in the backlash correction The plan was to use the slew direction to correct the backlash! WARNING!!!! this code works like the slew controls so its minimally override the DEC coordinates. Installation from zip file: 1. install AQESCOM - final version\EQASCOM_V200j_Setup.exe 2. Copy files from final version\common files\eqcontrl.dll to C:\Program Files (x86)\Common Files\ASCOM\Telescope or C:\Program Files\Common Files\ASCOM\Telescope, but make BACKUP first! 3. run EQMOD's toolbox and register eqmod.exe 4. Happy testing. In my case the correction ratio is 800 and duration is 290ms PS. Thank You for the developers to this great project!!! final version.zip
Hi, I was asked on a Swedish forum to put an "Astronomical Dictionary" on my homepage. I have made a test page in an easy form. Astronomical related words linked to wikipedia. It aims to the beginners in astronomy so it should not be too complicated words. http://astrofriend.eu/astronomy/astronomical-dictionary/astronomical-dictionary.html Let me know if it's useful and and I shall add more words. /Lars
I'm experiencing an issue with my CPC800 which is I can only describe as an issue with slew, mount drift or backlash: After a sucessfull PA (ASPA or 3 Star Align) I get the scope to GOTO quite accurately. I use the Celestron CrossAim 12.5mm eyepiece (CCelestron CrossAim 12.5mm Illuminated Reticle Eyepiece) to align on each star as accurately as possible and this has helped enourmously with GOTO accuracy. If the GOTO target is to east of the meridian the GOTO and slew are bang-on - tracking starts when the target is at the centre of the FOV. However, if the target is on the west the slew continues past the target. To stop this I have to press the handset button opposite of the direction of slew and then the tracking starts. I'm afraid I can't describe this any better - I wish I could post a video. Please, can any explain what is going on and perhaps suggest a solution?
morayskies posted a topic in Discussions - MountsHi All I have recently started using EQMOD to control my EQ5 Pro mount. When I use the mount with the SynScan Hand Controller I have noticed the usual backlash in the Declination axis when reversing the direction from north to south or vice versa. In the SynScan Setup/Backlash/Declination menu option, I find that setting this to 0deg 0' 50" (ie 50 arcseconds) compensates for the backlash when using the hand controller. My questions are these; When using EQMOD and the PC Direct mode setting on the hand controller, is this Declination Backlash compensation still applied? (I suspect not) Does EQMOD have the functionality to apply similar Declination backlash compensation when using the the direction buttons in EQMOD to control the mount? I intend using EQMOD's Pulse Guiding and see that there is a Declination backlash compensation for this feature. Please bear with me whilst I ask another couple of questions; I intend to use PHD2 as the guiding client. I think that PHD2 will 'build in' backlash compensation when it performs its calibration. If this assumption is correct, does this mean I do not need to enter any value into the Backlash compensation in the guiding area of EQMOD? Out of curiosity more than anything else, what on Earth would the value be I should enter in the EQMOD backlash compensation? On the SynScan the backlash compensation is entered as an angular measurement (ie 50 arcsecnds) but in EQMOD guiding it seems to be entered as a time value (ie between 0 and 2000 milliseconds ) Anyway, thanks for looking.