Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

stargazine_ep14_banner.thumb.jpg.27eb9b06c9c8a1fe5ac3bae21c92743b.jpg

Xplode

Members
  • Content Count

    966
  • Joined

  • Last visited

  • Days Won

    2

Xplode last won the day on February 23

Xplode had the most liked content!

Community Reputation

1,030 Excellent

7 Followers

About Xplode

  • Rank
    Proto Star

Contact Methods

  • Website URL
    http://www.gotaf.no

Profile Information

  • Gender
    Male
  • Interests
    Astrophotography, DIY
  • Location
    Norway
  1. Depends on the weight of the stones
  2. It depends on the filters, 50.4mm and larger unmounted filters are 3mm while all the mounted and smaller unmounted filters are 2mm thick. @james_screech How about just adjusting the exposure length or get a software with automatic color balancing like Pixinsight? Remember that a "balanced" filter set blocks light to achieve that balance so you get lower SNR.
  3. Did you verify good collimation with your camera?
  4. Something else to avoud when creating images to check collimation/tilt/etc is low altitudes, especially for color cameras there will be an effect from atmospheric dispersion that could skew the measurements. By looking at your images it's either tilt or collimation which is the main issue. You might want to take a startest to check collimation, use Sharpcap with short exposures, defocus a bright star and see how the donut looks.
  5. To get images to analyze you should take images of the same spot all the time, i suggest an area without a nebula/galaxy or star cluster, analyze the raw images, not the stacked one. Use shortish images and make sure they have good guiding. Don't trust your readings unless you get 5+ images with pretty much the same results, a variance of 5% isn't usual from an image to the next. To check if it's collimation, if possible rotate the camera 180 degrees to see if the abberation rotates with the camera or not. If it's sag/tilt because of weight check images before and after meridian flip, abberation will rotate 180 degrees. If you want good input on what the problem is you should upload some of your fits images. I have found that the numbers on spacing given by the manufaturer is rarely to be trusted, i try to always have spacers to adjust +/- 2mm available.
  6. If you want to use the guidecam on a guiderfinder the ASI174mm isn't a good fit, the pixels are too large, so are the Lodestars pixels. In that case the ASI290mm mini is your best choice.
  7. If you want a really great guidecam get a ASI174MM-mini, it's much better than the Lodestar, lower noise, larger sensor, more sensitive, faster download. In my opinion it's the best guidecam for OAG right now. The drawback is that it's quite costly.
  8. Uncoated glass loses around 4% due to reflections per surface, an uncoated camera lens could loose 50% of the light through reflections! It's hard to say for exact because of the different coating used by different manufacturers, but i don't think 1-2% per surface would be a bad number to use.
  9. Even with an open roof there will most likely be stagnant air in the observatory, especially for smaller observatories An open door in the observatory would help, but even better a fan, i suggest a fan sucking the air out of the observatory. A simple floor fan would be great for testing if you'd like to try. Do you have heaters on any of your mirrors? I've seen heaters with too high wattage totally ruin guiding/imaging. I recently helped a guy that had a heater on his guider finder and he instantly got better guiding by turning it off. The fan you have on the newtonian could in fact be the cause for the oscillations, might be a bad fan? Try turning it off. I usually recommend very good quality fans like noctua, it's also best to mount them with some kind of rubber mounting I believe the guiding assistant gives you exposure values based on the polar alignement/drift rate, i suggest you at least try longer exposure to see how it affects the guidegraph.
  10. There's a lot more losses than just from the mirrors/lenses, don't forget to take into account flattener/coma corrector, filter and the cover glass on the sensor.
  11. Taking a peek at one of the guidelogs i can see some oscillation in there too. Sometimes it seems to overcorrect so i would like you to set the RA aggressivenes to 75% of the current value. I also think you should change to a longer guiding exposure, looking at the unguided graph during the guiding assistant i can see there is a lot of jumping up and down which is an effect from bad seeing either high up, but more likely local. You might want to think a little about the thermals for your observatory and scope, it's incredibly important the both reach the same temp as ambient, an observatory should have some flow off air and the same would be great for the newtonian.
  12. Yes they will normally be gone if you have enough images and use the right settings, you will want to change the rejection algorithm to this. 8 images is minimum for this algorithm, but it's best with 20+ If some trails are still left you can try to change Sigma low/high, don't remember which one does what, but you'll figure it out.
  13. It's hard to say since it's so regular. It's either something creating vibration or it's the mounts RA motor tracking with a varying speed. Maybe post some images of your setup too
  14. Next time you are out imaging i suggest you take som shorter images, it would help find the frequency of the oscillations. What you need is a satellite trail that starts and stops within your FOV, counting the oscillations would make it possible to calculate the frequency.
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.