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masjstovel

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About masjstovel

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    Star Forming

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    Norway
  1. I'm finished processing now. Got the light ray removed - if you don't know it wasn't there you wouldn't see it is my conclusion. Before: After:
  2. @tooth_dr I will try to photoshop it out i think.
  3. Heres Ha integrated: Seems it moves a little, or its an extra beam luminating that doesnt have enough brightness for the eye in 1 frame (?)
  4. @Jamgood Its stationary yes. Thats why i thought reflection, since its "coming in and out" regarding luminosity. @ollypenrice Correct, it wasnt there for say 4 hours, then it was there for the next for hours. The difference in luminosity in the way it appears with most brightness in the middle and less on the sides makes me feel its not sensor/camera-related. @tomato I understand what you're saying, but then its strange it suddenly appears after hours of frames. I'm shooting at the same target now by platesolving, and its not there now. Doubt it has anything to say, but yesterday it appeared on both Ha and OIII at the same brightness, but today im shooting with SII.
  5. @Jamgood There was actually cobweb around when i took down the rig this morning. But i didnt check inside the tube. You were serious right? Would that appear like this? @ollypenrice I though about that too initially, but i checked and its not horizontal. Its sliiiiightly offset leaning upwards on the right side. Btw, you see the star improvement considering my previous thread?
  6. @tooth_dr Puh! And it was gone the next session again? Looks very simular indeed. Out of curiosity, which focuser do you have? I have the Baader Steeltrack NT and its an "open base" (flat and not curved), so that i was thinking some light has sneaked in there.
  7. Hi, Shot the Pacman nebula last night and some time after meridian flip (At least thats when i noticed it), this beam of light appeared on all my next frames for about 4 hours. Hopefully this is just a distortion from streetlights or something, and not sensor-related? Any clues?
  8. Update: so had a session last night again, and same issue as before. Was some peaks now and then in guiding, so couldnt tell 100% sure it was not guiding related. Then the guuding was as good as it never has been before at 0.54arcsec for 4x200sec exposures, and STILL the same issue. Then tried 60sec exposure and stars was fine, so problem was mechanical for sure. Set my guiding exposures from 2s to 1s to see if PHD2 ould sort out better the "invisible excursions", but problem was still there. With help from a friend from here at the forums he had a good idea and I slewed the scope in slow speed in every direction from EQMOD while taking short exposures to determine which axis the error was in, and it turned out to be DEC (no surprise there) Then made scope back-end heavier - quite much heavier ("a little off balance" can mean different things to different people) and then the stars was cute little round things again. So probably dec is making nudges and because of freefloating it goes haywire so fast PHD2 doesnt notice it before its back in "resting position" again. So that was the sollution in the end like you guys said. Thanks again! Too bad i found out in the end after 5 hours and 41 subs thrown away:D
  9. I probably wasnt clear about it, but this is the first time i see this result. I havent seen these starshapes on my other sessions, except bad frames with vibration (just thought the consistancy of angle and size and level of luminance this time through so many frames was odd). I understand what you mean with o-o and -o-, but could this be RA backlash? If RA is "too well balanced", or would it be more o- or o-- then since it would mainly "rest" in position? Its supposed to be clear skies tonight, and i think i will try to have DEC slightly off balance and see for some frames, and then maybe do the same with RA(?). Could also try a couple of targets in very different positions, ie close to horizon vs close to zenith etc. The method i did in PHD2 with new guidescope is ok then? Edit: the good subs was about in the middle of the session. Can check for obstructions in the line of view when i get home, but dont think so in that direction
  10. Thanks guys. Silly me forgot to mention one thing, which might be very important. I'll get to that. Well long story short: The infamous answer "I've tried everything" to get rid of the backlash. That means supertuning, changing all bearings to SKF, belt modding, and 8 months of pulling the rest of my hair off while adjusting the 2 setscrews back and forth. The result is: Gears grind "before" backlash is tightened up and gone. The only thing I have left to try is to add a teflon washer on top of the brassgear, as it MIGHT be in contact with the housing on the top in some poistions. So i learnt to live with it and has backlash-compensated in PHD2 (DEC) to the point of great satisfactory (usually). DEC alone has been down to 0.20 arcsec, and usually lays between 0.30-0.50 arcsec. (I Live in Bergen area which is known for its rain and clouds, so when i say usually, that means 5-7 sessions or ~35-50 hours) I had some oscillating issue with RA which turned out to be a to loose belt. So the last two sessions (~15-18hours) It has performed at 0.65-0.80 RMS total (Ra+DEC), which is very satisfying to me, at least after all the struggling. @ollypenrice; I believe what you are saying about the offset in PA, but because of the explanation above I am very afraid to adjust what I'm doing atm since i have been guided good lately (in my oponion) I have my camera Portrait oriented then, or chip aligned with the longside of the scope. So to the thing i forgot to mention: I have a new guidescope, which i used first time this session. Silly not to mention, but i couldnt get to think of it. I upgraded from Orion50mm to EvoGuide 50. It is attached in a clamp-shell so it sits very tight i believe. I doublecheck that the camera sits tight as well, but i believe so. To the point: Because of all the settings I was too afraid to make a new profile in PHD2 when setting up the EvoGuide, so all i did was change the focal length from 162 (orion) to 242 (evoguide) in the existing profile. Then i did a new calibration. I did not use Guiding Assistant. Its a helpful tool, but the recommended settings that come out of it hasnt really worked for me to be honest, so i have made my way by trying different settings and believe because of my latest guiding that its good enough. Is there something else I need to change here? But are these settings "optical" or mechanical sort of speak? Sorry for not mentioning the guidescope before.
  11. @ChrisWhiteYou were right! Found 2 frames which the stars look better: Had some sudden "jumps" in both DEC and RA from time to time, but that was maximum 2arcsec jumps, and didnt happen all the time, so wasnt enough to mess up the RMS mean (which was <1.00). Im thinking i might be too well balanced, so that the backlash made it "free float" in that area of the sky and/or wind.
  12. @ChrisWhite I agree it looks like vibration, but all the frames i kept is underneath 1.00 arcsec RMS, and that should be enough on my setup. Its ~70x200s frames and they all look the same characteristics wize (direction, length, size of "spikes"). I did check for snag during session, but couldnt find any. I am not denying it could be what youre saying, but with the info here i dont understand how, especially the consistency of it through the frames. It would be interesting to see frames up against the time of guiding, how do i do that? Only thing I can think of is - I do 2sec intervals in guiding. And i dont know how the interiors of PHD2 works, but there was slight wind (up to 5m/s, but probably less where the rig is), and if I aim at lets say a pixel, and windgusts push the scope away and back again to that pixel during the 2 sec exposure, will PHD2 know that it has moved? Silly thought maybe, I don't know. I think its something optical myself, but cannot figure what.
  13. I agree it looks like vibration, but as mentioned in my post, these frames guided <1.00 arcsec, and its also consistently pointing diagonally top left to right bottom through the frames
  14. Hi, I noticed most/all of my frames last night on NGC 6888 are looking funny, and i cant explain why. Can anyone help/guide me in the right direction? Imaging with what is shown in my signature below. Perhaps useful info: - I was guiding at <1.00 arcsec on the frames i kept. - The screenshot is from Ha-filter - Stars have not been looking like this before - I have added Bob's knobs since last session - the knob-heads look a bit big initially, but when try to look in the primary mirror directly behind the secondary i dont see them sticking outside the mirror. - I did collimate the day before, and havent touched the scope since then. - These starshapes are not local - they appear all over the images.
  15. So, got the Lynx cable and problem is sorted! Thanks for the help, guys!
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