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Carl M

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Everything posted by Carl M

  1. Thanks for the suggestions, rather worryingly I've found that these additional spikes are coming from the actual secondary mirror itself. I put my laser in and can see at the bottom of the telescope (on the primary) these same spikes appear. I thought it may be from the mirror being too tight, but I've loosened the collimation screws and the centre bolt but these same spikes are still apparent.
  2. Hi all, Last night seemed like a good night to try and get collimation of my Quattro 8s sorted once and for all (or so it seemed), but rather than sorting it I've opened up another can of worms! It was the first night where I'd completely ditch the laser for collimating the primary mirror and collimate on a star instead. So I pulled the star (Capella) out of focus and into the middle of the frame to get the concentric rings. The primary was not collimated because the secondary shadow was not centred. So I centred it and took a 30 sec exposure. What I got was a star with the 4 normal diffraction spikes, but on the same axis mirrored quadruple ones! I'm fairly sure nothing was intruding the light path as Capella was pretty much directly overhead. I've had a search around online and seen that extra diffraction spikes can come from twisted vanes but the effect never gave this many diffraction spikes. Other interesting thing to note was that when I moved the star out of focus again the secondary shadow had moved and was no longer central. But when I moved the focuser the other way to defocus the star on the other side of focus it was centred! Would that indicate a focuser that is not sitting square? Any help would be much appreciated! Thanks, Carl
  3. You have some nice detail coming through there despite conditions. Only criticism I can give is that it looks a little green, give it a run through Photoshop with Hasta La Vista Green plugin and it should sort it.
  4. Yes I agree it doesn't look like star trails. Looks like coma that is being exacerbated by a spacing issue. I'm sure I've seen something like this before when people are imaging through an eyepiece projection method.
  5. Don't give up hope on it just yet, when I modded my 1000D as part of my dissertation myself and my co-workers had to take it apart and put it back together probably close to 10 times...and that was with 3 different people. Initially there was no response at all when turning the camera on after modifying it..so we called it a day and thought it was probably dead. Next morning we took it apart again and reseated all the ribbon cables again, and like magic, it just happened to work fine again. I'm still using it to this day and have had no technical problems with it at all. Did you mark the ribbon cables with a sharpie or anything of the like? That's one of the things we forgot to do, it seems the ribbon cables are a bit picky on how they want to be seated. Perhaps go back to it another day and do the complete teardown again and try reseating all the cables again? This was what I was recommended to do, and although that was what we had been doing all along we still tried it again the next day and managed to get it working. At least yours was showing some kind of life after modifying, ours was just dead; no error, lcd didn't come on, no led on..not great motivation to keep trying
  6. Neq6 will be fine, my C9.25 is piggybacked with an ST80 on an older style EQ6 and still rock steady. You then have the option to use guidescope or OAG if you choose to autoguide. Most people would swear by an OAG when guiding an SCT, but can initially be a bit fiddly with spacing and getting focus with both cameras. I'd also recommend using the 12dstring FOV calculator or similar if you haven't already, you may find that some DSO's you want to image in the future won't fit fully in the frame (M42, M33, Andromeda etc..), even with the reducer. Other than that SCT's are great for the smaller objects.
  7. Yes you can use a C8 for small planetary nebulas and smaller galaxies, but it also depends on how well you are mounted and how accurate your autoguiding (or lack of) is because of the longer focal length. How are you planning on mounting it?
  8. Not sure whether you have it activated in PHD2 but it should save and deposit a guide log .txt file somewhere on your computer. If you have the log you can open it with a log viewer and show the graph from there as well as RMS values I believe.
  9. Thanks Martin, I agree the original is a bit too red - can see it especially in the stars. I added a star mask and de-saturated it a little to turn down the redness of the stars while boosting the blue and reducing the red a bit for the rest of the image. Hopefully this is a slight improvement.
  10. Thanks for that, if it were to be collimation would rotating the camera around the focuser change the direction of the worse corner in the image? I imaged M42 on the same night and looking at the images from that it shows that the top left is still the worse corner? Got me thinking perhaps it's something to do with the t-ring/coma corrector not sitting square - maybe even the sensor itself since it was self modified.
  11. PA first and then do the goto alignment. How do you mean rough PA using guidescope? You should only be using the polarscope of your mount to do your polar alignment, ignore whether you can or can't see polaris in any of your telescopes. You are attaching the polemaster to your mount to do your PA and not your guidescope? I'm no expert when it comes to guiding, but I've read that tolerable RMS is dependant on the equipment you are using. In either case I would assume that the lower the RMS better. Here was what my graph looked like on a good night, it's not always as flat but RMS was low and the pictures I was getting from camera were not trailing. Perhaps someone with better guidng knowledge can chime in if I'm wrong Hope this helps.
  12. It's a lot easier to fit in the frame, I had no end of trouble trying to get the whole of M31 and it's companion in the entire FOV a while ago. Felt like I'd tried every degree of rotation around the focuser with the camera!
  13. By pointing accuracy do you mean for the goto alignment? You can use your camera if you can get the star in the middle of your LCD. I find it's much easier to use a high power eyepiece to center the star then add the camera later. On the final star of the alignment attach the camera and use the star also for focus. Then you've finished the alignment as well as sorting focus for your camera ready for when you want to slew to your target. Your stars still do seem to be eggy, how is your guiding graph looking and RMS values? Since SCT has pretty long focal length any guiding or polar alignment glitches will really show up. Try and spend a night trying to get your guiding and polar alignment down to a T, it will really help a lot on future outings.
  14. Well it's fair to say I've spent way too much time trying to process this...which is probably a sign it needs more data as well as calibration frames - no flats/darks/bias. Still seem to be getting stars elongated at edges of images (worse in top left), which I cannot work out to be either coma or collimation, perhaps my Baader MPCC needs to be updated to a newer version (assuming it is coma)? Anyhow.. finally managed to get some data I was happy with and where the guiding was content. 21 x 300s at ISO800 Full spectrum 1000D with Astronomik CLS-CCD clip filter Quattro 8s on EQ6 guided with ST80 and QHY5II Processed in Photoshop and Pixinsight for DBE For just under 2 hours of data I'm quite happy with it! Thanks for looking, Carl
  15. I'm not too sure on that one, with a little bit of research I found this guide which supposedly gives a similar result to HVLG but using GIMP's implemented features. Here is the link. It's an automatic translation from French but seems understandable and gives a few different ways of trying it. Might be worth giving it a go, good luck!
  16. You've got rid of the hot pixel trails which is a good, your image has a green cast to it which can be removed with HLVG filter in photoshop. In fairness, I think you picked a pretty difficult object to image with the SCT. Crab nebula should be a much better target, how were the subs from that, stiill eggy stars?
  17. Blimey, a lot more long winded process than mine! As I say, not too familiar with polemaster, surely once you've polar aligned with that you should be done? In step 6 you say you are adjusting the bolts again, are these the latitude/azimuth bolts you used to polar align with polemaster? I would swap step 5 and 4 around. Polar align first using polemaster and then do your goto star alignment. Once you've aligned with polemaster you shouldn't need to touch polar alignment or the latitude/azimuth bolts again.
  18. I'm using a similar setup, rather with an ST80 guidescope on a C9.25. Was suffering from the same sort of trailing myself, and for me it was either polar alignment being off or from DEC axis being imbalanced. Not familiar with the polemaster or your PA routine, but I used to do polar alignment first and then put my weights and telescope on the mount..soon found out that after I'd put the weights on, polaris had moved in the polarscope. Presumably from not enough tension from the latitude bolts. This may not apply to you but might be something to consider if you PA the same way I did. After sorting PA and the DEC axis balance my PHD2 graph settled down (especially DEC) and was able to do 5 minute exposures with my C9.25 without eggy stars.
  19. As Steve says, you can't really use darks from another camera because it's highly unlikely that the hot and cold pixels are in the same place on both cameras (which may well be the cause of those dots you are referring to.) I would try and stack only the lights you have taken with the borrowed camera using kappa-sigma stacking method in DSS, or if you can, retake the darks and flats - may not be worth doing this until you get your guiding/PA sorted which is most likely the cause of the eggy stars. How are you guiding the SCT?
  20. Mine would be a Takahashi FSQ-85ED "Baby Q", seen some really good images taken with it and heard good things about it. Would also complement my other 2 scopes so I have options for wider fields of view and longer focal length with SCT. Most of all, I think at some point it will be achievable of getting one!
  21. Thought I'd take a quick snap of the moon while experimenting with my "new" C9.25 I got myself after graduating University, haven't had much time to use it as I'm still tinkering with the Quattro.. C9.25 on EQ6 1/100s ISO100 Canon 1000D full spectrum and an F/6.3 reducer to fit the whole moon in the frame. Modified to greyscale to fix colour and an unsharp mask to bring out a bit more detail in craters. Will test how the QHY5II performs next time and perhaps make a mosaic. Thanks for looking, Carl
  22. It certainly sounded like a discharge, like air being released from something. Makes sense since the damaged capacitor is bulged at the top and has a crack going across it. I didn't notice any burning smell after it happened or when I opened the mount up so fingers crossed nothing is fried. Thanks Mike, I suspect the link will come in handy if replacing the capacitor isn't successful. I'm going to order a replacement capacitor, if the specs of the replacement capacitor are the same as the original I assume the brand doesn't matter? I'm toying with the idea of buying a soldering iron and doing the repair myself although I've never soldered before, after being quoted £40 just to put in the new capacitor it's looking more likely!
  23. Hi all, Having recently come back from University and finally having the time to take up Astronomy again, tonight I made a very naive and stupid mistake. The power cable connecting to the mount snagged while using the goto and removed the tip from the cable. I then very stupidly connected the tip to the cable again and completely forgot the fact that the orientation of the tip matters. I then reconnected it to the mount and turned it on. Although I had a 50% of being successful, the dreaded sound of something not very good bellowed across the garden (and it wasn't just the mount). I've opened the mount up and had a look at the motherboard and the only damage that I can see is that one of the capacitors looks like it's blown. I'm not very familiar with electronics though and it could very well be more than that, but how can I check for damage if it's not visually damaged? Apologies for dodgy iPhone picture but the lower black capacitor on the left looks damaged compared to the one above it. Would it be a job of just replacing that capacitor and it should be working again? Thanks in advance, Carl
  24. After disassembling the camera and reconnecting the ribbon cables for the 5th or 6th time and having 3 different people put it together, it finally woke up! Thanks all for the suggestions. Michael - unfortunately not, however, you have given me something to write about in my write-up of the implementation. Cheers!
  25. Hi all, After just finishing a Full Spectrum mod on a Canon 1000D for my dissertation, it's now apparent that the camera is not powering on/displaying any errors on the screen at all. I followed all the steps provided in Gary Honis' modification step by step tutorial but when it comes to turning the camera on, it's just unresponsive. Is there anything more I can do than checking the ribbon cables or am I just chasing a lost cause? Thanks in advance, Carl
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