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Anthony RS

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About Anthony RS

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    Star Forming
  1. I always let PHD choose the star. That's not the issue.
  2. I didn't think of that thank you! But i doubt this is the issue since I've tried many different targets and different stars to guide on. But I'll keep that in mind. Thanks!
  3. One more thing if you don't mind, how did you plate solve the image and how did you know where the DEC and RA directions point?
  4. Btw how does pointing to the Zenith cause this effect if east heavy balancing isn't as it should. If you mean it could cause the RA axis to wobble, then that should appear in the guiding graph but it's not.
  5. That's very interesting Thank you! Most of my images tend to be similar to the 2 bottom images so perhaps I'm having some Dec issues. But what's confusing me is that my guide graph looks normal Here's a screenshot I took, unfortunately I don't have one showing the whole graph and the logs won't be of much help. I guess I'll have to narrow it down to flexure and/or dec error. Thank you that really helped.
  6. I've never had this issue even before I hypertuned the mount. I used to have >1.2" error with huge 4" spikes in the RA, and never got this exact issue. Now i have sub arcsec guiding with no spikes (very few spikes now and then but they do not always coincide with the bad images). Plus my reasoning is that even if there are spikes, they are usually really short and not enough to register such a bright second star?! It looks more like the scope moved entirely during image acquisition with no guiding correction which does not seem to be the case according to the guiding graph.
  7. Yep the rings have those plastic tips. My main issue is that I've been imaging with the same gear without any problems and suddenly I got this. Why would flexure suddenly appear out of nowhere. I always make sure the screws are extremely tight to avoid flexure. I will try to post some logs but the problem is that I was messing with the scope while guiding (checking for loose stuff, cable drag, etc...) so the log will have huge spikes that we won't be able to distinguish from actual guiding spikes and me messing up with the scope.
  8. Hello! I've been having this issue for a while now, and I've been trying to find the culprit with no success. This is driving me crazy. For some reason, I've been having weird stars in my image, where it's not a typical star trail, but the stars are actually doubled or tripled in more than 50% of my images. I've attached an image with different previews from different images, one of the images in these previews has good stars while the others have weird stars which seem to go in different directions in each image. Here are some notes: -I'm using a celestron AVX with the 8 inch newtonian telescope, Canon 500D with SKywatcher aplanatic coma corrector, 60mm guidescope with zwo asi 120mc-s. - My guiding looks normal, I'm having the issue with guiding error of 0.8" and my image scale is 1"/px. I've had no problems before even when my guiding error was 1.2" - The dec graph seems to swing from north to south sometimes due to backlash but the error is always below my image scale. I think I've tried to guide with dec guiding off and had the same issue but I'm not sure (been a while since I've tested). Plus, I believe that if the problem was strictly due to the Dec behaving strangely, the star "trails" wouldn't be in a different direction in different images. Correct me if I'm wrong please. EDIT: After reviewing all the images. It seems like the trail of doubled stars is mostly in the same general direction (in most images but not all). - My RA is always below 0.8" - I'm positive my PHD2 settings are correct in terms of focal length, pixel size etc... - I'm using a cheap 8 inch newtonian (celestron). I always collimate before the imaging session. I even checked collimation after the imaging session just to check if the mirrors are moving during imaging, causing this problem, but collimation always seem to be spot on after I'm done. - I have tried to extremely tighten everything and all the screws you can think off. All the adapters, guidescope rings screws, literally everything. - I tried a different camera. - I've tried different exposure times from 180s to 300s, and different PHD2 parameters. I have yet to try exposure times of less than 180s. - It gets cold really fast during the night at the location where I'm imaging, maybe that could be causing the scope or the mount to cause this problem in some way. - I tried to image with dithering off. I first suspected that maybe APT was sending dither commands randomly during the image (although that should appear as a larger error in PHD2 guiding error) - I thought it might be the focuser or focuser's draw tube moving due to the weight of the camera but that would mean that I'm losing focus so I've checked focus several times during the night with a Bahtinov mask and it never changed. SO could the problem be the mount behaving strangely and not showing in PHD graph? some movement in the scope? bad collimation? flexure somewhere in the imaging train or guidescope? I'm really our of ideas so I was hoping someone could have some ideas or experience with this. The image I've attached might help in the analysis hopefully. I'd appreciate any insights and recommendations. Clear skies, Anthony
  9. I understand that but my worries is star bloating since the CLS-CCD is also a UV/IR Cut filter. My camera still has LPF#1 but I'm not sure it's enough.
  10. is you DSLR modded without removing LPF#1 filter? If yes, are you seeing some star bloat? Thanks
  11. Hello, I've modified my Canon 500D (t1i) following Garry Honis' video; however, I did not replace the IR cut filter with a clear glass filter. I just removed the IR filter and put back together all the other filters. I'm using a Newt. with the Skywatcher Aplanatic coma corrector. Here's my issue, I already have the Astronomik CLS-CCD filter which is a light pollution filter as well as an IR blocking filter but I will be shooting M81/82 in bortle 4 skies this weekend so I'm not sure if using the CLS-CCD is a good idea. First, I'm in relatively dark skies with low light pollution, second, I'm shooting a galaxy, which as far as I know, and please correct me if I'm wrong, the CLS-CCD will do more harm then good blocking probably some of the details or requiring much longer exposures to get the same details as without the filter. I could remove the filter since i'm not worried about light pollution, but would that cause bloated stars since I'm using a coma corrector? or are the remaining filters in the DSLR enough to block IR? If removing the CLS-CCD does mean I'm going to get bloated stars, the question is can I remove the filter to get as much detail as possible from the galaxies and deal with the stars in processing, or is keeping the filter not that detrimental to galaxies? Appreciate any insights and opinions especially if you have any experience with this. Cheers, Anthony
  12. Hello, I've modified my Canon 500D (t1i) following Garry Honis' video; however, I did not replace the IR cut filter with a clear glass filter. I just removed the IR filter and put back together all the other filters. I'm using a Newt. with the Skywatcher Aplanatic coma corrector. Here's my issue, I already have the Astronomik CLS-CCD filter which is a light pollution filter as well as an IR blocking filter but I will be shooting M81/82 in bortle 4 skies this weekend so I'm not sure if using the CLS-CCD is a good idea. First, I'm in relatively dark skies with low light pollution, second, I'm shooting a galaxy, which as far as I know, and please correct me if I'm wrong, the CLS-CCD will do more harm then good blocking probably some of the details or requiring much longer exposures to get the same details as without the filter. I could remove the filter since i'm not worried about light pollution, but would that cause bloated stars since I'm using a coma corrector? or are the remaining filters in the DSLR enough to block IR? If removing the CLS-CCD does mean I'm going to get bloated stars, the question is can I remove the filter to get as much detail as possible from the galaxies and deal with the stars in processing, or is keeping the filter not that detrimental to galaxies? Appreciate any insights and opinions especially if you have any experience with this. Cheers, Anthony
  13. I did use a very small amount of grease after I cleaned since that's what others usually do when hypertuning their mounts. Wouldn't using more grease make the mount sticky and sluggish again?
  14. That makes a lot of sense actually. I'm not sure if the worm and gear are perfectly aligned although I did use the same spacers that were before. So I guess there's nothing I could do except wait till I can upgrade to a better mount.
  15. Thank you William for your great explanation. Unfortunately, I live in Beirut, Lebanon so I have no one to go to. I've hypertuned the mount myself and so I'm checking if everything is as it should. I think the grub screws are tight enough but I'll double check. As for the worm-Ra gear mesh, this is where it's getting tricky with me. I seem to have a lot of backlash in the RA axis which shows as slop and free play. No matter how much I reduce the spacing (till the motor binds) the slop is always there, I've also tightened the worm's locking ring but the free play is still there. I was wondering if you know what could be the cause of that. According to Ed from DSP, free play is unavoidable since before hypertuning, grease was masking this slop, but after cleaning and re-greasing, there's no way I could fully get rid of this slop. I'm worried now that I might have the worm-gear mesh a bit too tight to avoid even more free play but I don't know if loosening it a bit more would cause my tracking to get worse. I've got good tracking results during my last test but I don't want to cause any damage to the worm and gears ?
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