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Nik271

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Everything posted by Nik271

  1. Here is a comparison of the the positions of Vesta on 18 Feb: And on 22 February:
  2. I also spent an enjoyable hour at 8pm watching the Moon. The seeing was poor, so I stayed below 100x with Mak 180 with binoviewers and a pair of 32mm Plossls. One extra bonus of the binoviewers: they cut the glare of the Moon by half ๐Ÿ˜Ž I particularly liked the shadow that promontory Laplace was casting from the tip of Montes Jura on Sinus Iridum. I think I can even see it in the image by @paulastro above Then I hunted down Hagrid's dragon NGC 2301 in Monoceros. Hadn't seen it until now, at 100x it was framed very nicely, and despite the moonlight looked very good indeed with big spread 'wings'. And then the clouds arrived around 9pm
  3. Actually I did not use a mount at all, just a basic tripod. The key is to use a fast lens and take multiple exposures which are then stacked in a program called Deep Sky Stacker (DSS). You can find tutorials about it in the imaging section. But actually you don't even need to use DSS to show the stars up to 7-8 magnitude, DSS is needed to reduce the noise and show up faint nebulosity which otherwise will be lost to the noise. The particular detail of the above photos are: Canon EOS 250d camera with 50mm F1.8 lens. I took 9 exposures of 4 seconds each at F1.8 and ISO 400 and stacked them. Then I played with curves and levels in GIMP to improve the contrast. For the duration of the exposures I follow a very conservative '200' rule: 200 divided by the focal length of the lens. It used to be '500' rule in the age of film but modern cameras have small pixels which show the star blur too much and I found '200/focal length' works for my camera most of the time. By the way this video goes in depth about the most accurate rule: Of course if you have motorised tracking mount you can do much longer exposures with accurate polar alignment. I just believe that for wide angle shots you can get good results without tracking. It certainly saves time setting up when taking night photos especially if you need to move the gear somewhere out of the way in the dark. There is a a ton of knowledge about imaging in the other sections and it rapidly gets very technical and the gear very expensive. For me - I stick to brighter objects and try to keep it simple. Clear skies! Nik
  4. Any observing session is better than a cloudy night. 520x on Moon is very impressive! I have never gone beyond 450x in my Mak but a 12 inch scope should be capable of this and more. Must be a beast on the planets. Last night I stayed below 180x as there was some high cloud and only the Moon was punching through it. It was still worth it - Copernicus looked lovely near the terminator. This evening seems more promising ... ๐Ÿ™
  5. Indeed, there is something magical about watching the sky, an image just does not convey the 'here now' moment for me. I can compare it to a listening a recorded piece and going to a live concert. The recorded music is usually better quality but the concert has an extra dimension to it which is very difficult to describe. Same with visual astronomy, it has a connection to the cosmos I just can't get from images.
  6. Just to give illustration of the dramatic difference the altitude of the target makes, compare these two photos. I was trying to photograph Vesta in Leo yesterday and spot its movement. First photo is at 8pm and the second is at 10:20pm. Sadly Vesta did not move visibly but compare the level of detail visible. In the 10pm photo I can even spot the faint Leo triplet. At 8pm: and at 10pm:
  7. I was looking at M94 and M97 at 10pm. The moon was lower and behind a tree which helped. My biggest difficulty with DSO is actually not so much the sky but the ambient light around me which makes dark adaptations almost impossible. Its so bright that I can read a large atlas in the ambient light So I use a thick towel draped over my head, which helps quite a bit
  8. An update from 18 February. Vesta is moving North -West still close to 88 Leonis. This is an image with 50mm F/1.8 on Canon 250D, stacked 18x 4s exposures. The time was 10pm on 18 Feb. The bright star in the lower left is Denebola.
  9. Yes, they should be visible. Last night was very clear here. I saw M94 and even the Owl nebula M97 which had eluded me until now. I used an 7 inch Mak, which is not really a DSO instrument, a 6 inch Newtonian will be ideal.
  10. I found that the Seyfert galaxies are easier to spot from light polluted skies with a 5 inch scope. These galaxies have a very bright core, which makes them easier to see as opposed to more diffused galaxies. From the Messier list M51, M66, M77, M81 and M88 are Seyfert galaxies.
  11. Last spring I observed M94 on multiple occasions with a 5 inch Mak. I agree it is relatively bright and stands some light pollution. My skies are Bortle 5 bordering on Bortle 6. It's a nice target indeed! While you are in the area check out M63, another relatively bright galaxy close to Cor Caroli. It makes a right angled triangle with M94 and Cor Caroli:
  12. Don't underestimate the effect of atmospheric extinction especially in light polluted skies. You should try to discover in which direction you have darkest sky and look for galaxies there. South will be best of course. To illustrate I was looking at Vesta in Leo last night around 10 pm. Right now it is at magnitude 6. I saw it in 20x80 binoculars and I could see the mag 6 stars around it, but not much else. The bins should be able show me stars up to mag 10 and even the Leo triplet which was nearby but I didn't see even a hint of it. Had I waited until midnight when the Leo triplet passes the meridian my chances would have been much better.
  13. I managed to observe Vesta yesterday with 20x80 binoculars at 10pm. It is just over 6-th magnitude and was roughly halfway between Denebola and Chertan (Theta Leonis), close to the 6-th magnitude star 88 Leonis. Here is a sketch: I'll try to follow it over the next month whenever weather allows, it should get even brighter in a couple of weeks.
  14. Well done, this is an excellent set up. The 127 Mak is very versatile and portable. Almost any eyepiece will perform well with it because at F12 the light rays converge very slowly and don't demand expensive corrective optics. My advice is to get something with as wide field of view as you can at your budget. For example the 15mm StellaLyra has 68 degrees FoV and is well priced by FLO. I often use a 10mm aspheric Svbony (63deg FoV) with my Maks which performs surprisingly well.Can be found for under ยฃ15 on eBay. Just stay away from the 6mm EP from that line , it's not good.
  15. I would say that the camera sensor is the least important issue, people get good results even with 10 year old DSLRs. The key is for improving deep sky image is to get enough light on the sensor. You either need to expose it for longer (so you need a tracking mount like the EQ5 or the Star Adventurer) or you can use a very fast lens, for example I have used 50mm F1.8 Yongnuo lens to get reasonably good images of extended objects e.g. the Pleiades, or whole constellations. With 50mm you can achieve 5-6 second exposures on a fixed tripod without star trails which at F/1.8 means 10 times more light that at F/5.6 with the Tamron. But at some stage if you are serious about photographing DSO a tracking mount is unavoidable, otherwise there is no way you will get a minute long exposure without star trailing. The faint DSO definitely require long exposures especially if you use filters to cut light pollution.
  16. I had a similar experience as @Waddensky last night with 180 SW Mak: The disc size of Sirius was well controlled most of the time and a couple of times I thought I saw a fleeting pinpoint north-east but it did not reoccur regularly enough to be sure. I believe 250-300x is the right magnification to use in my scope: Sirius B is almost 9-th magnitude and being low in the sky atmospheric extinction will make it even dimmer. And magnification larger than 300 will make it just too dim. Magnification 250x should make 11'' separation appear as 44' in the eyepiece, so hopefully wide enough to separate from the glare. I'm still waiting for the perfect night to see the Pup๐Ÿคž
  17. I often use my Mak with the 32mm Panaview, again giving 70 degree FoV. Haven't noticed vignetting. I know there must be some because of the field stop is larger than the visual back opening, but the vignetting is not noticeable to me in dark background.
  18. You won't see more than the 4 stars, but it's worth revisiting again to check the nearby Struve 761, you will notice a pair of close stars and then a third star nearby in the same field of view as Sigma Orionis, as @Jiggy 67 suggested. This is another gravitationally bound pair but they haven't moved very much since they were first observed.
  19. The fifth star B is actually a close companion of the brightest star A, at a separation of 0.3 arcseconds. I doubt many people have the monster scope and seeing to see it at the eyepiece. Perhaps it can be imaged. Actually the main star Aa has another super close companion Ab at separation .007 arcseconds currently. They complete an orbit each other in just 143 days! So there are in fact six stars in the system but with <1 meter aperture equipment we can only see 4.
  20. To view some brighter asteroids (Ceres, Vesta, basically anything up to mag 8-9) you only need binoculars and an accurate star chart. Vesta is brightly visible this and next month in Leo, it is the brightest asteroid reaching magnitude 6. For imaging the dimmer asteroids, you need a small telescope, camera (DSLR or dedicated astro-camera) and a star tracker (or motorized equatorial mount). The gear rapidly gets very expensive. Personally I stick with visual, others should be able to advise on the imaging in greater detail.
  21. You had a lovely session John, despite the clouds! My clouds were coming with very short gaps (<20 mins) between each wave, so it was: choose a target, point, look quickly and then back in the house waiting for another gap. I still managed a decent haul: saw Pi Arietis as suggested by @John This triple star is at moment near Mars with quite dim secondary and tertiaries (10mag), my 180 Mak showed it nicely at x250. I looked at Mars briefly, but no sight of the UAE orbiter Then Alnitak, Sigma Orionis, Algieba in brief sessions. Theta Aurigae was a nice catch, the seeing was very good at the zenith. Looked at Sirius but it was dancing too much lower down. There was progressively more and more cloud so I packed up around 10pm. Today the forecast looks very good, fingers crossed!
  22. Glad to hear that! If you can see the Bode's galaxy then all the other clusters in Cass should be nicely visible in the 12x50. You must have darker skies, here I moved to bigger bins (20x80) largely because of the light pollution. A 10x50 pair does not show me mag 9 stars, it did not even show Eunomia at 8.5 a few weeks ago and I had to use the the big bins.
  23. It's been pretty bad this winter, it may go down as another of the wettest on record. Here on the Thames floodplain it looks like we are on the edge of the sea already. Having said that I managed to get up at 3am this morning for a forecasted gap in the clouds. It was clear for about an hour, I looked at some old favourite galaxies with a 6inch Newt. I had one of my best views from home of M51 which was near the zenith. A small benefit of clouds is that if there is gap of clear sky the rest of them block the light pollution
  24. It's the sky conditions: even the slightest decrease in transparency can make these near invisible. I decided to give it a try with my 6 inch Newtonian last night but there was too much cloud initially. I went to sleep and got up at 3am when it was supposed to be clear. However mist was rolling in from the west where Leo was. I knew exactly where to look but even with the 20mm EP at x37 and 4mm exit pupil I had a lot of difficulty spotting M65 and M66 between the banks of the mist and I was using averted vision, tapping the scope, towel over the head, the works. They were just faint ghostly blobs appearing and disappearing as the mist went by. There was not even a hint of NGC 3628. By contrast the M51 the Whirlpool was right at the zenith in a patch of clear sky and the mist around it was acting as a screen from the light pollution. I enjoyed very good views of its two cores. Last year I struggled a lot with M51: I was trying to see in when it was lower down and through light polluted skies. I'm in north Oxford where it's Bortle 5/6 so can only get a clear view of the DSOs when they are near the zenith and in ideal conditions. Keep trying, you can see them but the conditions have to be good.
  25. I've seen the triplet in a SW 127 Mak with effective aperture only 119mm. So a 6 inch scope is perfectly capable of showing the triplet. I find them by pointing the scope roughly halfway between Chertan and Iota Leo. Just wait until they are at least 40degrees above horizon to avoid as much of the light pollution as possible.
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