The Moon continues to wane as it moves along the ecliptic, passing 3 south of Saturn at 4 P.M. EDT. Now I am suspecting either the focuser or the mirror housing flexingunder its own weight. observe the astigmatism over several hours to see if it changes or goes 8:55 PM on Jun 1, 2023 CDT. Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. Your stars are mostly good, and then a little excursion at one point. To learn more, see our tips on writing great answers. Many challenges come with astrophotography, but one of the most critical skills to master is achieving pinpoint star focus in your astrophotography images. This technique is particularly useful for short focal length camera lenses, where a suitable star focusing mask may not be available. Ok I need to try and sort my stars out, especially the smaller ones are elongated. The exception to this is with refractors employing an optical design known as a Petzval, in which there are four lens elements, the front pair correcting chromatic aberration and the rear pair correcting field curvature. 1 Celestron NexStar 4SE Check Price 2 Celestron Inspire 100AZ View 3 Celestron AstroFi 102 Telescope View 4 Celestron NexStar Evolution 925 Computerised Telescope Check Price 5 Celestron Astro Fi. NOTE: Stars at the 4 corners (not shown) look the same - showing this same flare. What is the 500 Rule? A defocused star test will show this distortion in the Airy disk. he instructions This will allow you to capture as much light as possible. no By using this site, you agree to our Terms of Use. Aug. 2016), All images and text Copyright Mike The image in the middle was defocused slightly. NOTE: Lasers can We have placed cookies on your device to help make this website better. Below, well explain what causes the most common aberrations found in amateur telescopes. Catadioptric scopes like Schmidt-Cassegrains, Maksutov-Cassegrains or Ritchey-Chrtiens require a baffle tube to prevent light from the front of the telescope falling directly onto the focal plane before reflection from the primary mirror and this can cause vignetting. may even be seeing more than one Thanks for the replies so far. Pinched optics can be corrected by slackening off the retaining clips on the primary mirror so that they just hold the mirror in place, or by careful adjustment of the lens cell in a refractor. Many of the standard Bahtinov Masks available allow you to adjust the size by moving adjustable pins along a slot. Place your Bahtinov mask over the end of your camera lens or telescope objective. Its easy to get lost in your images, try to make sure you dont spend so much time zoomed into the corners of your images. (The vertical field of view of a 600mm lens is 220', and you have 4000 vertical pixels.) Try using small sensors with big pixels, they are a lot less demanding and one of the reasons we see so many great 314/414 images. collimation. focuser, here are some other mechanical tips. The autoguiding is done through the ST-237 guide chip of SBIG ST2000XM. More ideas appreciated. So, none of my answers really help tell you what is wrongWhile they may be interesting, they are not solving any problems. Using the And if that doesn't work, make a not-for-not-to-do BF. gets closer to the center of the field of view of the eyepiece. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); This site uses Akismet to reduce spam. Just something like a 10-second exposure, then really critically assess the stars in all corners/edges and the center. Distortion in star images that is caused by distortion As you adjust the focus of your lens or telescope, the central diffraction spike will move from side to side between the two X shaped diffraction spikes. looks like, remove Autoguiding was performed via ST4 with second chip of SBIG ST2000xm like previous time. Use the magnifier feature on your camera or view the image on your laptop. Something tells me it might be a mixture ofperhaps twoof the above. Most of the time, focusing in astrophotography is a manual process that requires you to adjust the focus by hand. I'm not sure the Baader MPCC Mk III is capable of coma correction for full frame. Despite this, it demonstrates the importance of being in focus. take 2 min, 15 min exposure of Alkaid; as you can see the stars are almost round in all images. I enabled autoguiding and let the system taking L subframes for a period of 1 hour. Astrophotography Help: rings/ circles that are artifacts in my images These initial focus positions will help you avoid a situation where you are too far out of focus that stars become difficult to view on the live view screen. Polar Alignment For Astrophotography | Aligning How-To Guide Use Ctrl-H to toggle off the "marching ants". Edited by PirateMike, 29 October 2020 - 08:48 AM. It ensures that the gears stay meshed and that the worm is lifting the weight. A good amount of detail is shown in the nebula, with lots of fine structure and contrast visible. I have recently been having a similar problem to yours. The Sky This Week from June 2 to 9: See a Full Strawberry Moon The subexposures were 1 minute. Basically I am scratching my head as to what the problem is and any help would be much appreciated. I do not see anything - Last night I looked down the barrel from the front - nice clean margin at front objective\lens cell, nothing looked amiss - ditto with the baffles. I think focussing is good as the Sony allows *11 mag on the image on rearview and I also have a Bahtinov mask. One helpful tool is the Bahtinov Aid, which is part of the excellent Astrophotography Tool image acquisition software. The problem with the elongated stars still continues. Why is Bb8 better than Bc7 in this position? We can all look up and appreciate an exceptionally bright moon or a surprisingly clear night. As the knob is adjusted, the telescopes optical tube assembly will move in or out, physically changing the length of the telescope and with it the distance from the objective lens to the eyepiece or camera sensor. This gives you a chance to see some example images using many of the filters referenced in this post. APT will now display an overlay over the diffraction pattern and let you know how close you are to being in focus. Website: http://www.budgetastro.netTwitter: https://twitter.com/#!/BudgetAstroFacebook: http://www.facebook.com/BudgetAstroFlickr: http://www.flickr.com/phot. I have gotten rid of the coma by making the A 3-4 steps bigger ie from 5.6 --> 9.0. In this video we cover how to put stars back into your astrophotography images after removing them in PixInsight. It can be a frustrating hobby when adjusted properly isn't perfect! power you are using - if it is fairly low, the distortion may be coming Follow the steps below, and you will be able to get excellent sharp stars in your images. 3,438 5,164 Posted November 24, 2014 offset the balance slightly to keep the gears meshed, otherwise there can be "bounce" which will give elongated stars. If your telescope is perfectly collimated at this point you should see a tiny white dot centered within the shimmering diffraction pattern. Why does photographing the Milky Way require short exposure, when star trails need long exposure? Even if that is the problem I still have the asymmetry between each corner so why is that? The Williams Optics Zenithstar 73 comes with a Bahtinov Mask integrated into the lens cap. The New Orleans Pelicans brought him in on Thursday. Use something like ASTAP to do this. Taking that extra time to get your focus right will save you disappointment and frustration. Third Before hitting GO on your exposure plan, it is worth taking a few final test shots to double-check that you are completely happy with your focus. Rumor: Rams Considered Trading Into 1st Round of NFL Draft If all those stars align into the round of 16, it would be the third meeting betwixt the Canadian and the Pole, with Swiatek holding a 2-0 edge. I dont get many clear skies here in the UK, so I applied a simulated lens blur to the image. Extra horizontal spacing of zero width box. In fact, just about everything concerning the SCT is complicated except for its relatively simple design (other than that dratted corrector). Temperature can have a big effect on this aberration with a telescope, especially a refractor, having no apparent problem until the temperature drops and the various components start to contract. Stars not round at corners The Los Angeles Rams brought home quite the haul in the 2023 NFL Draft. I am fairly new to astrophotography and been at it about 6 months. If its oscillating between + and corrections youll need to turn down the aggressiveness. The 2023 NHL draft will be June 28-29 at Bridgestone Arena in Nashville, and the Stars do not have a first-round pick after trading it to New York . Before you do anything else,determine if you have First thing dont open the mount up (unless its already been tampered with). And they do not usually show as a spike on the side of a circular star. Unfortunately the image posted is a low resolution and on my screen it shows round center stars but with a slight donut effect (slightly darker in the centers) which could be a focusing issue that would amplify the corner issues further than normal. It's not just celestial mechanics that makes Venus "pop," thoughplanetary science is a factor, too. You need to be a member in order to leave a comment. I know the Astrotack is perfectly aligned to the polar star as the stars in the middle of the picture are still round even with 3 mins exposure. Without a subpoena, voluntary compliance on the part of your Internet Service Provider, or additional records from a third party, information stored or retrieved for this purpose alone cannot usually be used to identify you. Once aligned, hit the Recalc button. Bianca Andreescu breezes past second French Open hurdle | The Star This is fairly simple - if the stars in the telescope do not Fix: Go with threaded connections only, or ensure your camera is (very) securely mounted (compression rings are bad). When a star is in perfect focus, the central spike will be positioned exactly between the two X spikes. Last night I started a astrophotography session with my equipment. if the telescope is f/5 or below. some possible causes of non-round stars. Thanks for that advice. As you approach the focal point, you may start to see fainter stars pop into view; this is a good indication you are on the right track. Collimating Your SCT For Best Performance Round Star Tips - Atik Cameras The fine focus will typically give you a 10:1 reduction, giving you excellent resolution and precision for finding the exact focal point. Check out Astrophotography Tool or APT here. Once you are happy that the central diffraction spike isexactly between the X spikes, thats it. Astrophotography: Removing Purple Star Halos - Sky & Telescope But that starts allready quite near the center. This last test will provide the answer if mispolar alignment was the reason for getting elongated stars http://myastroimages.com/Polar_FinderScope_by_Jason_Dale/, Sensor centrality problem bugging me (is it even a problem? The Elephant Trunk was taken with a 300mm Canon lens, 1.4 converter, using 20x5min Ha, OIII, SI, a skywatcher 50ED guidescope and S. could you describe? Landers Nolley II Works Out With Fifth Team Ahead of 2023 NBA Draft Save 50% when you subscribe to BBC Sky at Night Magazine today. From Then replace draw tube adaptors for screw fit. I rotated the camera 90 degrees with no change. Plan to be outside for several hours. Once centred and magnified, you can begin to refine the focus. You may have multiple issues besides spacing. I am going to again try different backfocus even though the spacing is per coma reducer spec.The results are similar on different nights with new collimations each time, which look good with my Cheshire eyepiece.I wish I had a different coma reducer to try. Example - last night I started imaging Rosette Nebula, 120 sec exposures of Rosette Nebula, I was using a 2" Antlia ALP-T filter. Try to get some shots before it cools down and see if the stars are any different. You currently have javascript disabled. I thinks the trails are not caused by backlash of the mount. Jun 1, 2023 4:45 PM EDT. If the was good with periodic excursions, you would see those spikes in some images, but not in others (depending on the period of the error). The PA is usually very good and the PHD graphs are as flat as a pancake. Relating to the If the stars in the corners are misshapen and look different in each corner you may be experiencing tilt in your optics. Is PixInsight worth the cost (and the learning curve). By making successive adjustments, you canput the I adjusted the back spacing on the FF back and forth and even sent them a Bahtenov mask focus photo to verify to them the scope was indeed in perfect focus when taking photos accompanied by the example star shots. Elongated Star Repair w/ PhotoShop - bf-astro.com Coma is an aberration that occurs predominately in reflectors and manifests itself in the appearance of comet-shaped stars with their brightest portion pointing towards the centre of the field of view.