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Everything posted by Erquy

  1. hi, i have the gt81 on avx and love it, great combo, easy and portable in/out garage on few meter (all together, included camera), and more than happy on what i get with the sx694/mini fw/ lodestar and 0.8 FF, it is indeed difficult to balance using the original short vixen type dovetail as supplied, the camera/ff/fw is heavy and while extending to 7cm the focuser, it makes it back 'very' heavy if one use the original dovetail. you simply need to buy a longer dovetail (no need to 'replace' the original dovetail, simply add it under, there are screws under the original -in fact need as well if you want to reach easily the locking screw on the focuser -if you do not want to turn it-. otherwise consider ring set up. below example in narrow band and rgb https://www.astrobin.com/201680/C/ https://www.astrobin.com/full/202339/0/ i cannot comment if you may face problems with only a dslr at the back without any FF
  2. ChrisH, thanks for the link, but they do not seem to have the one (double spur gear, the inner part being metal, outside of plastic, it does not seem easy to find)
  3. thanks. it is 2,5 year old. i guess it has been running some 150-200 hrs in total (setting + imaging time + visual)
  4. hi it is just to share some experience with repairing my avx: suddenly, i started to have a severe knocking issue with the RA movement: by guiding i could identify it coming periodically, exactly 6 times per 10 min, exact same smooth guiding in between ( i have guiding typically betwen 0.6 to 1.2 rms depending conditions with the avx with either c8 or the wogt81): a big jump in RA guiding in phd, up to 7-10 arc sec, lasting 2-3 shot (2,5 sec each), and corrected.... I unmounted the ra motor and its cover: you find 4 spur gears: 1st very small in white plastic, 2sd one metal (inner part) and white plastic (outside part, in contact with the 1st small one)) the other 2 are in metal. the 2sd one was the problem: it looks a bit like below left picture ( picture from internet, not exactly that one , the black being white, unfortunately i did not take a picture and now it is back in) the issue it was broken from the metal/plastic to the edge (as illustrated on the right by the black mark) so i fixed the issue by taking the same part from the dec motor and replace each other. now the problem is on the dec, but at least, with proper PA, i can run several hours imaging without getting on that failure. of course, i would like to find a a good replacement, but i could not find any of such spare part any where. anybody has a clue where to find spur gear spare part of an avx motor ? (deep space product offer a full ra motor, but i do not need that, only this little inner spur gear). has anyone a broken avx ra motor to offer (or simply the inside spur gear ?) thanks in advance
  5. my oiii replacement is on its way (really bad one of the serie, stretching hard, i do get halos with stars of mag 9.5-10!!), but i would like to stress all perfect with r,g,b, ha, sii baaders, all parfocal, either with my c8 or gt81. so despite the oiii batch issue, i recommand baader.
  6. Hi, So this is invert vignetting. I have been in the same situation. Do you have the histogram of you stacked flats? i did manage to adress the problem (not totally, but you can finish then with dbe) by manipulating a bit the master flat before stacking: move/transform the histogram of the master flat (keep the original safe!) and stack (use masters, and do trials and errors with fewer subs). If your imging set up has not moved, then try take different flats and find the right ones (or check around for flats methods) My learning: keep your optics/sensor as clean as possible and do not go for flats if you do not have too severe gradient -dbe can take well care of it- (depends how bad is your gradients of course). I have not used flats for long, only pay very much attention not too have dirt on sensor glass/fr and that s make life easier.
  7. Upgraded from win 8 to 10 All below ok (all last versions as i am aware of) - phd2, nebulosity 4 - eos movrec - stellarium - Sx 694 driver (neb4), lodestar driver (phd2), - ascom filter wheel (for sx minifw) when using in neb4 (i use neb4 to capture) (lodestar and minifw connected to the sx964 mini usb port) - pixinsight
  8. A first attempt for a slight 3D video effect, from my heart Nebula http://www.astrobin.com/201680/C/ hope you like it: using hitfilm express ​ ​
  9. Hi, a narrow band heart nebula WO GT81, with 0.8 FR. SX 694, with baader Ha, S and O. Guided with lodestar, on avx mount. 7*600s each filter (3,5 hr in total). Processed in pixinsight. I am suffering of halo with the Oiii filter. enjoy
  10. thanks. I did manage to address a bit better the halo around the brightest 2 stars: http://www.astrobin.com/193262/B/
  11. Dear all, last night wizard. 4*600 sec each S/H/A. processed in pixinsight WOGT81 with FR0.8, SX min FW, baader SII,Ha,OIII. Lodestar, SX 694, AVX mount I need to work out halos (coming from the OIII filter). Any tips (I tried to halo reducer script but I have difficulties)
  12. just about 10 min ago C8, f6.3, canon 1200d. about 800 frames.
  13. Hi, I am pretty happy with my PhD guiding my AVX mount /OAG with Lodestar/ either imaging at F6.3 with the C8 or with my WO GT81, using SX 694 camera: I manage 600 sec exposure with well round stars (some issues time to time with DEC guiding, but fixed when correcting only in north or in south). but by curiosity I loaded some of my guided PHD log into pecprep and it looks like there is residual PE due to the worm cycle (below is a guided log): it is pretty small, but it looks like being still the main origin of RMS I have left to correct. It is quite surprising as I would expect guiding addressing easily and totally the main worm periodic error. Or will there will be always some residual PE from the main worm? Note that the problem is there whatsoever I use PEC or not and this comes in any of my log to about same extend. The PE of my AVX is about +/-16 arcsec and well reproducible and smooth. Is this normal, or not? If not, any tips to improve? My PHD settings are pretty standard ones, given directly from wizard, 2,5 sec with hysteris algorithm, (aggressiveness 70, hysteresis 15, min 0.25 pixel for the C8 at 6.3 (and smaller for the GT81). No big deal, as anyhow my results are all fine despite this, but I feel maybe borderline when imaging with the C8. So if I could further improve, that could be welcome.
  14. välkommen! Trevligt att se nån skåningar (?) runt här
  15. Hi, below a 1 st trial for narrow band, IC1386. C8, at 6.3, AVX mount guided with Lodestar I have been struggling as nights are getting short in Sweden, and sky glow is no longer very much stable, continuous slightly getting dark and then lighter again (I need to eliminate a number of exposure at the beginning of the session, as the different lightness seem to mess up a lot when integrating and processing). So I end up with only selecting carefully : 4*600 sec for Ha 3*600 sec for Oiii and Sii each all bin 2 so for only 1,7 hours in total, I am quite happy http://www.astrobin.com/182144/ but I think the season is finished now with those short nights for deepsky, I will need to wait late july
  16. thanks for all comments. I did some reprocessing to preserve the core, as well to further clean up the noise, and to me it looks even better now http://www.astrobin.com/178949/B/
  17. thanks for all comments. For sure I will add on data , when sky and nights allows (I am in Sweden, and nights are getting shorter, cannot start imaging before 11.00 pm now, the season is soon finished up here, to restart later in july). But I am happy for 100 min data (and the jpeg posted here is pretty bad I realise now as compared to the original -strange enough as compared to save my DSLR final image were typically giving way high size, -when resized to similar pixel w/h as above. Olly, I read a number of your posts, yes you convinced me till my wallet permitted it ;-)
  18. Hi, After several years with DSLR, I took the plunge to CCD... and I wonder why I have not done it before (... pocket money of course!). C8, F6.3; AVX mount Guided Lodestar Trius 694 mono (TEC -10C), sx mini filter wheel LRGB Baader, 5*300 sec each filter, total 100 min . 10 darks, 40 bias. Captured in Nebulosity 4.0 processed in Pixinsight. Wonderfull camera and the combo is lodestar/SX FW is working great.
  19. We always complain about the clouds, but tonight was a great thunder storm show, so I gave it a try for a first time (canon eso 1100d, 8 sec shot, iso 200). Now cloud cover and rain... I will try at next opportunity
  20. Thanks for the comments and confirmation on the increased sensitivity towards the celestial .equator. I will look at dec guiding in 1 direction next time out.... (and i don t know when... I unfortunately broken the mini usb connector of my canon tonight, so i am off untill this is fixed.... (too many cables around!)
  21. Hi, after 2 years of imaging unguided (with AVX mount, either with a C8 at F10, or F6,3 and recently with a WO GT81, 0.8FR and using canon EOS1100d as imaging camera), I decided to go for guiding. I have a Lacerta EOS oag with a Costar guider. I use Phd2 and through ST4, all basics works. I could set up and made some trials with the WOGT81/0.8 and to my surprise I got 10 min subs with all round stars from the 1st trial and I could even find a small window to try with the C8 at F10 and also manage 10 min sub (but only 1 before clouds come in as it took some time to find a guiding star, so not real conclusion there, but it looks good ;-). In case of the GT81, the OAG/costar works great, no issues to find a guiding star, works great. I did pay attention to balance as well PA (after being used to image unguided, I can say I am trained to make sure I have a good balance and good PA with the AVX -I typically manage 100% usable subs for 1 min sub at F10, 90 sec at F6,3 and 180 sec with the GT81, and I could push a bit further, but I prefer to insure 100% of usable subs, so I always set this exposure time). So a very good guided start, but now I am looking at PHD lab to understand better and I see big differences on RMS. based on 2 different session with the GT81: 1) a combined RMS of 1,63" for the guider on 1 hours run (targeting the Rosette nebula). Below link to 5*10 min http://www.astrobin.com/170146/B/ 2) a combined RMS 0.92" for the guider targeting M51 (the moon was up and thin clouds came in, so I took only 2*10, and they were very much washed out, not usable, but I still let it guiding as it could to simply see how it worked, and it run for 1 hour very well) As I am imaging with the canon EOS1100d, above RMS are well satisifying and as mentioned I got great results in both cases on 10 min subs. All setting basically the same as default input from phd2 (RA aggressiveness 70, hysteris 10, mm, min pix 0,21, max 2000ms). I did the calibration for each night, and taking into account the declination of the targets for the calibration steps. Calibration worked out without any problems reported. During those 2 sessions , I did change up and down some of RA (in a range 50 to 90), hysteris (in a range 5 to 15) min pixel move (0.15 to 0.26), but I could not see effect on the combined RMS for each runs (some little up and down, but 0.1). I used 2 sec exposure time for the guider. RA Osc inbetween 0,30 and 0,35 which I understand is a good value. No particular strange deviation as I have seen reported in some phd graphs. My questions: - is this expected that higher RMS will be obtained, if one imagine near the equator as compared to imagine near polaris with basic same setting (Iwould guess so as less to work out for the move near Polaris?) as I have seen comparing targeting M51 and the rosette - is above results decent ones, or shall it be possible to get even better results.If so, what factor shall I look at to further improve? Thanks for your help and comments in advance! below a screen shot of the 2 runs I refer above as from Phd lab.
  22. Hi, I discovered only recently this retailer and as I have not seen any post related to them (seraching for AST in the search engine), I thought it was worth to report: https://www.astromarket.org/ They have an impressive offer with many items one can not easily find elsewhere and also a number of previews on upcoming new gear (which I have not heard anywhere else so far). I did my last purchasing there (WO GT81 and AVX mound +some other smaller stuff) and it went very well on all aspects: they contact me within hours after setting my order and kept me updated (there was 1 item not in stock, so it took some days before shipping). Quick response and pint point answers to question I raised. Everything arrived well packed and as expected. I did tested the new gear and all works fine. regards David
  23. Hi, looking for a wider field and faster than my C8, I just acquired a WO GT81 (and corresponding FF) to use with my DSLR. This is my 1st APO. I am very impressed by the built and looks very solid. I have seen a couple of people reporting issues with focuser, but it seems to be previous models or unluck, the R&P is very smooth, easy to focus very well and sturdy (note I only use a canon EOS1100, so quite light to stand). Below almost a full frame 6*2 min unguided at ISO1600 taken tonight on M44. Nice round stars all over the field (maybe 1 pixel out in the corner). I pushed the saturation to high level and one can see some little coma on the edges/side, but not big deal to me (I would not push color saturation anyhow that much, that was only to check). I would recommend it (although nothing to compare;-)
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