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Shaun VS

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Everything posted by Shaun VS

  1. As I have advised someone else recently with the same scope, I would avoid trying to go too wide, unless that is you are young and live in a date site. The main reason is exit pupil, for people over 50 it rarely exceeds 5mm, and any light source may affect dilation as well. As such I would go for a good quality wide angle eyepiece between 25 and 30mm max. Another benefit is that you are less likely to have problems with astigmatism. And finally whilst you will have a wider field, your limiting magnitude will be lower (increasing magnification means you see fainter stars, up to a point that is, being dependant on seeing and optics). i hope this helps.
  2. May was a spectacular month for clear skies, 21 in total. Despite the light nights I managed nearly 800 variable star estimates. This month, June has been cloudier but still logged 6 sessions. Saturday night was crystal clear after a thunder storm, seeing stars below 10.5 with my 20x80mm bins. When people are able to meet up again properly, try and get an observing session with someone, you would quickly learn.
  3. Hi Andy, welcome to the world of astronomy. Enjoy.
  4. Try to pick up the keystone of Hercules which will be to the right (preceding) of Vega. Now using binoculars find the upper right of the four stars, then from this star look to its lower right and you should see a small fuzzy ball, this is M13 a bright globular cluster.
  5. Please don’t go down this route. If you want higher magnification then go for a telescope. I use 10x50mm and 20x80mm binoculars every clear night.
  6. Just a quick note re your reference to a 32mm eyepiece. If you go down the line of the 150mm f5 reflector, please bare in mind that that this combination would give a exit pupil of approx 6.4mm. Now if you are an older observer(50+) or observing from a brighter location, then your pupil will not dilate to that size. In effect you will not get the full 150mm. i would therefore suggest your minimum magnification should be around 30, which equates to an eyepiece in the range of around 25mm. Should you go for the longer F ratio scope then 32mm is fine, even desirable.
  7. My observing sessions vary from 15 mins to 2 hrs depending o n commitments, weather and inclination. My main focus is variable stars for which my main instrument is a pair of 20x80mm bins. I will often go out for 15/20 mins when things first get dark then again later in the evening. if I am going to use one of my scopes then I have to be certain that it is going to be clear for at least an hour, to be worth setting up. My longest session ever (with short breaks) was 9 hrs.
  8. Great website and some fantastic photos, video. I shall keep an eye on your site to see how it progresses. Good luck
  9. Shaun VS

    I'm back!

    Welcome back Jim, certain aspects of our hobby have moved on with technology, but the beauty of the night sky is still there for all. I hope the darker skies of Dorset are rewarding. Shaun
  10. I would start by taking a look at some globular clusters, M3 in Canis Venatici’ M5 in Serpens and M13 and 92 in Hercules. You could then move on to others in Ophiuchus.
  11. The 10x50mm bins are the better choice. My main reason is the size of the exit pupil. On 7x50mm it works at a fraction over 7mm (50/7), whilst 10x50 give 5mm. Now as the typical dark adapted pupil is 7mm the 7x50mm appear ideal, however in urban skies or older as we age this figure drops so the wide field of 7x50mm cannot be used. In effect you are reducing the aperture of the lenses. Therefore 10x50mm are more useful. A second benefit is that the limiting magnitude in 10x50mm will be fainter and at such low magnifications it will split stars easier. I hope this helps
  12. From what I understand, at the moment you don’t own a Barlow. I would therefore suggest that you try out the eyepieces you have. A Barlow will not improve the eyepiece that you use, but if you buy a decent one it will double the magnifications of both eyepieces and be useful with any additional eyepieces you buy in the future. If however you are not happy with the eyepieces, in particular the 10mm then I would take the advice from flo. For what it’s worth I never use a Barlow on my 10” f4.
  13. I’ve seen M1 in my 20x80mm bins, but other than saying I saw it, I can’t add anymore. I agree that including M1 as a binocular object could to say the least cause frustration.
  14. I don’t know about anyone else in the UK but May has been the clearest month on record for me since one really cold, clear February in the 1980s. I’ve been out at least for a short while with my binoculars. The main issue that it doesn’t get dark enough till after 11pm (22:00 GMT), and even then it’s bright to the north till after midnight. Next month will be even worse! still, around 700 variable star estimates in one month is much higher than normal.
  15. Sorry missed the important bit......10”Dobsonian.
  16. Great report. A number of years ago I remember reading an article about pushing the limits of limiting magnitudes. ASI seem to recall there were examples given of very faint DSOs and Halley’s Comet. The basic principle is that for very faint objects photons appear randomly, even as a cluster, meaning that an object can be seen fleetingly. Observe it several times and later check on the position and it could be confirmed. The principle is the longer you observe the more chance you have of detecting it. Takes a great deal of practice to master steady, constant averted vision. Anyway I tried it out and glimpsed a 16th mag star in the field of AY Lyr. Was it worth the 30 mins, I will leave you to decide?
  17. Using a right angled finder is easier than trying to crane your neck look up when the scope is low down. Having said that I must say I don’t use them, preferring a straight through finder. Why? I agree that the image is the correct way up but it is still inverted left to right. Being a variable star observer I use 200+ star charts. They are generally printed either as per the naked eye or as it will be in the reflector. As such I prefer the finder to have the same orientation as the scope. It’s all horses for courses.
  18. I’m not sure that a plastic bolt would be sturdy enough. In your position I would phone up a specialist telescope dealer. There are several in the uk I have used, all have provided a good service. At least you will know the price of the bolt.
  19. I think that the one factor that needs to be included is lens quality. For achromatic lenses the longer focal ratio will exhibit less false colour and hence finer detail. With apos the colours are brought together better, thus giving sharper images. The shorter focal ratio is then less or not an issue.
  20. I use a Skywatcher 130mm reflector on a Skywatcher AZ5 mount, which is a great light weight set up. The only negative aspect is the column extension, this makes the tripod less stable and has a tendency to loosen. I therefor don’t use it, and have no issues.
  21. I have a Skywatcher 130P which I have taken off its GOTO mount and put on a altazimuth mount. This has become my pick up, plonk down andobserve scope. The optics are good on my copy. One additional thing to consider is where you will keep the scope and observe from. The best telescope is one that gets used.
  22. I own two pairs of binoculars, Pentax 10x50mm and Celestron 20x80mm. My 20x80s are my most used instrument and travel with me. My main interest is in variable stars and they generally allow me to get down to around mag 10 under my suburban skies. You can’t beat some of the stunning star fields. Take variables in the Double lustre in Perseus or those near eta Geminorum.
  23. It is a fact that as you increase magnification so does your limiting magnitude, although there are diminishing returns, and considerations such as seeing and optical quality. Try it. Download a variable star chart from the BAAVSS or AAVSO. Take my 6” Dobsonian a couple of nights ago at x40, the limiting mag was 11.5, at x105, 12.4 and x220, 13.1.
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