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mark7331

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Everything posted by mark7331

  1. To answer point 3) - yes and sidereal rate should be selected by default. If it isn't select it. I've switched it off by accident before and PHD says it's guiding but it's not.
  2. Hi Chris, I completely agree but just to clear this up I'm not looking for a certain number of calibration steps to get guiding working. They are just an indicator that the settings are OKish. The point of changing the guide rate is that the mount doesn't take enough notice of the guide commands when the values are set too low. I started, by mistake, with both RA & DEC set to x0.10 and for ages have struggled to get the mount to keep up with the guiding. Once I changed the rates (to x0.30) my guiding started working. My approach is to get a guide rate that works well with a calibration step. If it's too low it doesn't. Regards Mark
  3. Bamus, glad to help mate The EQMOD pulse guide rate should be set before you calibrate and if you need to adjust it again you should re-calibrate PHD because it's a major change to the responsiveness of the mount. I'm not sure you're going to need to set the backlash value in EQMOD. Once your calibration is reasonable in DEC it may not be an issue any more (mine is also "0") but maybe that's because I have different mount? So I can't find a direct way of measuring the backlash but I wondered could you use the EQASCOM trace feature to work it out? Right click on the ASCOM logo in EQMOD to see the trace. If you watch/record the log while PHD is clearing backlash it might give you an idea of the number of ms you'll need. I checked the PHD debug log and I couldn't see any backlash related data. Just to be thorough I have the EQMOD minumum pulse width set to 20ms. My RA guide rate is x0.30 and DEC is also x0.30. I'm really interested to see if making these changes takes out your DEC bumps (as it should do) as it would be great to have a clear procedure for getting rid of these kind of guiding issues. Keep us posted. Mark
  4. bamus sorry if you know this approach already but I thought it might help to share my method for calibration. I understand your frustration, I've experienced it myself, but there should be a fix for reasonable guiding. So:- I started by working out a calibration step value that produces between 10 and 20 steps when calibrating. Leave everything else as default until you can produce this. If you're using EQMOD you can change the RA & DEC Pulse Guide rate to help reach the calibration "zone" you're looking for. If you're using the ST4 (Autoguider) port then adjust the guide rate to help - you may need to do this with your handset. Once you've found a good calibration step/guide rate pair then take some exposures of increasing length and modify the MaxRA and MaxDEC durations. Once you have a reasonable image then tweak the other settings (RA agressiveness, hysteresis etc) to smooth further if you need to. In my experience the guiding graph isn't really a useful indicator of good guiding. I've taken some long exposures where the stars are perfectly round but the graph has appeared quite bouncy. So my message is don't worry too much about the graph. Take some subs, note the settings you used to get them and compare to previous subs. You may find you're getting good images with a crazy looking graph. Sorry if you've heard this all before but I hope it helps. Mark
  5. Brilliant app - I've just downloaded my copy. Thanks for the heads up.
  6. Dew is pretty common and as Biz says don't worry too much about it. At the end of the evenings viewing I place my tube with the mirror facing down in the house with the dew caps off. You've mentioned dust but you only have to leave it long enough for the scope to warm a bit and the dew will disappear. Do this every time and it won't be a problem. If the dew bothers, as Umadog said, you a fan fitted to the back of the tube will help keep it at bay by drawing air over the mirror. I really wouldn't wash the mirror unless there's major debris on it. I've only washed my primary once, shortly after manufacture, because of metal and other rubbish left in the tube. Although Umadog suggests a hair dryer I would advise against it. It's just my opinion but I think that you can end up blowing muck onto the optics and compound any problems. Also be wary of blowing hot air onto cold optics - you don't want to risk a crack. Just my opinion. Hope this helps. Mark
  7. mark7331

    Hi there :)

    Hello Swift and welcome to the group
  8. Looks brilliant. Really nice round stars - even the small ones. You know I think the graph can be misleading. That's why I always take a sub to actually see what's happening. Who cares if you have a lumpy graph when you can take 8+ minute subs like this. I think you've cracked it! Nice one. Mark
  9. Tommy and the Monster are right (Hey that sounds like the title of a Roald Dahl book! ) Seriously this is a good effort. You've found it after a search and you managed to image it from your SE alt-az. It has discernible detail and form. I think that's very impressive.
  10. Malcolm that looks better. Your graph looks good and stable. Getting good five minute subs is a major achievement. I've been really trying to push PHD and now I'm getting an almost flat line on the graph but to be fair I only have clouds to contend with not an airport! I think with a bit of tweaking you could get your RMS down a little (and maybe longer subs if you need them). My OSC is usually about 0.30 and RMS 0.11 although I had it down to 0.06 yesterday. Since you have the same guide scope/camera as me I wondered if these settings would work as well for you? I am now able to reliably get 15 minute subs depending on the seeing. My current settings (which have lasted three sessions now) are:- EQMOD guide rate of x0.20 Guide exposures of 2.5 seconds. CalStep 1500, RA Agr 80, RA hyst 12, MinMo 0.15, MaxDec 110. EW calibration happens in 22 steps and NS in 10 steps. I hope this is useful info. It'd be nice to be able to build up a picture of some useful groups of settings. Regards Mark
  11. Looking really good so far Martin. I agree with paraman - it's pretty spooky looking
  12. That's a cracking image! Brilliant detail in the spiral arms and lovely colours.
  13. That's a very good idea. It would help you see what was going wrong and how to improve the guiding. Mark
  14. Looking at a satellite feed like Sat24, one eye on the sky and making your own mind up is the best approach as, in my experience, all the forecasts are useless. Mark
  15. Hello Luna and welcome to the group
  16. Both for me too but I don't use DBE unless I really have to. Good flats can be enough.
  17. John you can try adding shorter exposures but another technique is to make a star mask and then try stretching everything apart from the stars. You can pick up the nebulosity without blowing out the stars. Just be careful that you don't leave a dark halo round them. I did this in PixInsight by creating a star mask and adding a range mask to it so the larger star halos are included. I'm sure you can do this in Photoshop. Hope this helps. Mark
  18. I really like this Mike and to have produced it under such poor conditions is amazing. The version without flats is shocking! I also agree with Olly that it doesn't look over processed at all. Quite beautiful. Mark P.S. If you get the chance a full review of your gear would be great.
  19. Malcolm, sorry I should have said, that's in EQMOD. I previously had it set to x0.1 and had to have a calibration step of 3500! Now with x0.2 the step works fine at 1000-1200 ish. Mark
  20. Malcolm. Choose the exposure length according to the brightness of the star that you've picked. The latest PHD tells you when the star is saturated so you can reduce exposure time. I typically start at 2.5 seconds and change accordingly. Also I've found that changing the calibration step has a greater effect on the smoothness of the graph and guiding than the other settings. Try a higher step (say 1000) and when the graph is smoothish play with the other settings. With my NEQ6 set to a RA guide rate of x0.2 I am using a cal.step of 1200 and my graph is pretty much flat. Hope this helps Mark
  21. I use EQMOD with my NEQ6 Andy. The handset is cool but the direct connect allows me to align and slew around using Stellarium/Cartes Du Ciel on the PC. You get complete control from the keyboard. I've found polar alignment & star alignment much easier with EQMOD. When you've aligned and are looking at an object you can see the aligment stars your're using and it's help me make better choices for accurate alignment. From within the EQASCOM control panel you can also set the guider correction rates etc, use a gaming pad to control the mount and lots more. It's all there in one place. Also once you've setup EQASCOM to control EQMOD you don't need to tell the mount the date/time or Lat/Long any more. It knows how to position the mount for polar alignment etc. It's a breeze. Mark
  22. I've recently switched to Artemis Capture because it's nice and simple. I used to use AstroArt 4 to collect subs after aligning/focusing with Artemis but changed because I just didn't need the complexity of switching to AA. For guidng I PHP - it's free and works well. PixInsight for stacking/processing. Mark
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