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About kens

  • Rank
    Proto Star
  • Birthday 08/05/1961

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  • Gender
  • Interests
    Deep sky, fly fishing, cycling
  • Location
    Melbourne, Australia
  1. Aaaaarrrggggghhhhhh - help please !!

    My Atik 420 is one of a couple of devices I have where it is important to connect the USB port first and have it live before connecting power to the camera.
  2. Auto Guiding Star Adventurer

    PHD2 needs input from a guide camera which it uses to calculate guiding corrections and send them to the mount, in your case via the guide camera The guide camera needs an ST4 (autoguiding) port to connect to your mount. The guide camera can be attached to either a guide scope or to an Off Axis Guider (OAG) which picks off some of the light coming through your scope and directs it to the guide camera.
  3. PHD2 help

    Make sure the guide scope/cam are focused properly. Do it in the daytime on a distant object and/or focus on the moon first. The PHD2 display always auto-stretches so if you are out of focus it stretches the noise giving a grainy appearance.
  4. This is not uncommon as it is not obvious when calibration is taking place if you are not accustomed to it. It might be possible to get some sort of popup added when calibrating so you know to wait. Calibration is THE most important activity in PHD2 as it needs it to work out how big and in what direction the corrections are needed. Once you've calibrated, run the guiding assistant for 10 minutes or so and use it recommendations. Tick the box the does backlash calculations as well.
  5. That means you have't calibrated yet. Start looping, select a star (or click Alt-S or Tools>Auto select star) then click the Start guiding button. PHD2 will start calibrating automatically.If you have any problems from then please attach your guide log for analysis. Its in Documents\PHD2
  6. The marking on the mount show your latitude so the angle from horizontal is 90 - latitude. e.g. at the equator (latitude 0) the wedge would be vertical or 90 degrees from horizontal. The markings also assume the tripod is level and that the markings are accurate - which they rarely are. So for your latitude of 33 deg the wedge will be at an angle of 57 degrees
  7. But for serious polar alignment we have BQ Oct! And we have all the best objects as well @Gavin1234 your best bet is to use a compass and inclinometer app to get aligned at first. In due course you can use more advanced methods.
  8. That's right. But if you are imaging and therefore have a camera attached it is possible to work out the alignment of the mount with four main methods - three of which are implemented in PHD2. First there is drift alignment near the celestial equator where the drift rate near the horizon and meridian is proportional to the PA error in altitude and azimuth respectively. This is also exploited by DARV and AstroTortilla. Next there is polar drift alignment (PDA) which where the drift rate is proportional to the total PA error and the drift direction is orthogonal to the PA offset from the pole. As far as I know only PHD2 supports this method. The third called Static PA (SPA) in PHD2 (as it does not rely on drift) is also used by Polemaster and Sharpcap. In this method one measure the position of a given star near the pole at two or three points while rotating in RA. The centre of the circle that passes through the points indicates where the mount's RA axis is pointing. The fourth method uses a sky model built up from many alignment points to map the RA and Dec reported by the mount to the actual RA and Dec that it is pointing at and can therefore work out where the mounts RA axis is pointing. Of all the methods, polar drift alignment is unbelievably simple to use. Just point near the pole, pick any star and start the drift. Its good for getting an alignment within 10' or better in just minutes. Beyond that the noise from seeing and the mount impair the drift detection as it needs to detect ever smaller drift rates as you approach perfect alignment. I then switch to one of the other methods (usually SPA) to fine tune. These methods are generally easier to perform with a good initial alignment.
  9. Try the Polar Drift Aignment method in the latest development snapshot of PHD2. You point at the pole, select any star then press the button. After a short time it setles and shows on the screen where you need to move the star to (using the alt and az knobs). Its good down to about 10 arc minutes error. Once you are there you should calibrate and then any of the other tools are easier to use to get more accurate PA. The other new tool in PHD2 is Static PA which also operates near the pole with an algorithm similar to Polemaster but using your guide scope or imaging scope and, where possible, automated slewing of the mount. But the classic Drift Alignment is the most accurate of all.
  10. As already stated the mount is the most important item. Astrophotography is like terrestrial action photography with a long lens in the dark. It is one of the most technically complex pursuits imaginable. The equipment and techniques needed to image the planets is quite different to those needed for galaxies, nebulae etc (also known as DSOs or Deep Sky Objects). Planets are usually imaged with a video camera rather than a still camera like a DSLR. They require a long focal length scope with minimal chromatic aberration. If that is where her interests lie then you should budget for a good Astro video camera as well. Bintel is a good reputable dealer in Sydney. But the previous posters are right. Don’t buy it yourself, let her choose or chances are you’ll get it wrong and get in the way of getting the gear she really needs. Sometimes even secondhand is the best option. Your best bet Now is to get her a good introductory book on astrophotography.
  11. I can’t think why the NEQ6 would guide more accurately than the EQ6-R. Who told you that? Both mounts would benefit greatly by being guided via PHD2.
  12. The light from your target and the sky glow add together. The faint nebulosity will be a little bit above the sky glow. You only need to expose enough to overcome the read noise of the camera (identified as the left hand edge of the histogram curve). Beyond that you are losing dynamic range in your images where the dynamic range is the highest possible signal divided by the sky background. Thats why light pollution is a problem.
  13. Things to look for in a camera: Sensor size determines the field of view. Whats the biggest thing you want to image? Pixel size determines the granularity or the images. Whats the smallest thing you can/want to resolve Full Well Capacity and read noise determine the dynamic range (FWC/RN). Whats the brightest thing you want to image without saturating Cooling capacity for noise reduction esp dark current - important for longer exposures Plus you may also consider the ADC depth, back focus, amp glow, reflection and so on.....
  14. Power supply for vixen GP..

    Be careful with polarity. Some Vixen controllers have the polarity reversed - that is they have centre negative instead of the centre positive. I don't know which way the DD3 is wired but check first before you plug in a 12V supply.
  15. The direction doesn't atter as you'll get backllash in both directions. Just set the dec guiding direction to correct for the drift whatever direction it is.