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John

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Everything posted by John

  1. Yep - you can get a "3 for 1" deal with a low power eyepiece M110 is quite a bit fainter than M31 and M32 though, especially if there is some light pollution around. Nice triple galaxy possibility though.
  2. Nice shots folks. Interesting object. I managed to track it down visually with my 100mm refractor a while back. Quite hard work with that aperture, visually !: https://stargazerslounge.com/topic/350271-ngc-2419-a-very-very-distant-globular-cluster/
  3. Yes, as long as the barlow element is able to be securely screwed in and it does not contact the lower eyepiece optical element, you should get some form of amplification of the eyepiece. Probably somewhere between 1.2x and 1.5x ? I tried it with a 4mm non-Baader ortho eyepiece and it worked quite well.
  4. I ought to add that using the lens element set of this barlow screwed directly into an eyepiece barrel needs a good 15mm or so clearance up inside the eyepiece barrel to get it to fit. Many eyepiece designs today have lower lens sets within the 1.25 inch barrels which reduce the amount of clearance quite considerably so you just cant fit the barlow lens in. The thread that screws into the filter thread of the eyepiece barrel is on the lower end of the barlow optical set so you have to be able to insert the whole of what is quite a thick lens set before the thread engages. Also you do not want the barlow lens set to contact the lower lens of the eyepiece. Generally orthos and plossls and work OK with this but not more complex designs. The amplification might vary from 1.3x depending on the eyepiece used. I suspect 1.3x refers to using it with the Baader Classic eyepieces. Hope that all makes some sense !
  5. I have one of those and use it a lot. The optical element of a barlow lens has a focal length like an eyepiece does. The distance between the lowest lens element in an eyepiece and the barlow lens together with the focal length of the barlow lens determines the amplification that you get, ie: 1.3x, 1.5x, 2x etc, etc. The further that the eyepiece lower element and the barlow lens elements are apart, the larger the amplification factor. This works Ok within a certain range and you can actually get a variable barlow lens (Meade made one in the past) where the barlow element could be slid along the tube and locked to vary the amplification given. Quite a lot of zoom eyepieces work on a similar principle with a sliding amplification element situated below a fixed upper element both built into the body of the eyepiece with a twist mechanism to vary the distance between them. The thing you have to watch for as you change the spacing between the eyepiece optics and the barlow optics is that the focal position of the combination tends to change as the spacing increases with the impact being that bringing the combination to focus in a scope can get awkward if the scope focuser does not have enough travel. Also the eye relief of the eyepiece can get extended to the point where finding and holding the correct eye position can get tricky. So that's why I said it works OK within a certain range. The Baader VIP modular barlow lens works on this principle with quite a wide range of amplifications being possible using various spacers. It uses a higher optical quality lens than the Q-Turret 2.25x barlow, and better fitments generally, hence the higher price: https://www.firstlightoptics.com/barlow-eyepieces/baader-vip-modular-2x-barlow-lens-125-and-2.html Personally I use my Q-Turret 2.25x barlow in it's 2.25x mode with a zoom eyepiece and the whole combination works really rather well as a 9.55x - 3.2x zoom
  6. I have a couple of pairs of the Zeiss Jena 8x30's one of which is about 40 years old and also a pair of 8x30's made by Swarovski in Austria which are a similar age. The body condition reflects their age and a lot of use but optically the views are really crisp and bright. Another good quality if a little old fashioned make are the Russian Komz or Tento branded ones. They are rugged, usually reasonably priced and optically very sound.
  7. Very nice report ! It was a lovely clear, if cold, night here as well. Once you have had a break from observing it is very nice to get back into it and re-visit "old friends"
  8. First chance tonight since I posted this thread. I took the "sledgehammer to crack a nut" approach with the 12 inch dobsonian. I didn't think the seeing was that great but E & F Trapezium were showing fairly easily so I gave Sirius a go when it rose above the rooftops. Once my eye had adjusted to the glare from the star, I found that I could spot the Pup star fairly readily as a point of light gleaming shyly though the outer "skirts" of the glare from it's far brighter companion using 268x (6mm eyepiece). The Pup star was trailing Sirius A as it drifted across the field of view. I was able to repeat this at 199x (8mm EP0 and 338x (4.7mm EP) but I think that the 6mm made things just a touch easier. Pleased to see the Pup again for the first time this season
  9. Nice report ! I visited Australia for a month in 2018. We had great weather but mostly cloudy nights. I did manage to use my 8x56 binoculars a few times and observed the Magellanic Clouds and also the wonderful globular cluster 47 Tucanae close to the SMC (in line of sight terms). Wonderful sights Wish I'd been able to spend more time observing while down there We will have to come back again !
  10. I'm not a binocular expert but I have a pair of the Helios Naturesport 10x50's and they seem good performers to me. When in stock they are just a bit more than your budget new: https://www.firstlightoptics.com/all-binoculars/helios-naturesport-plus-50mm-binoculars.html The Helios Fieldmaster looks to be a similar spec and is within your budget. I've not tried those though: https://www.firstlightoptics.com/classic-binoculars/helios-fieldmaster-50mm-binoculars.html I have three pairs of Opticron binoculars as well in different sizes and they seem to be good performers for a reasonable price too.
  11. Surprise clear night tonight, moonless too, for now. Got the 12 inch dob out and it's cold but pretty clear and dark out there. Scope is close enough to the house for the dining room table to be the accessory tray Eskimo nebula at 338x with the UHC filter is exquisite
  12. Your report has inspired me to get my 12 inch dob out tonight . Surprise clear sky here without a moon. E & F Trapezium and a lot of other stuff looking lovely
  13. Great report Magnus You may well have seen the Horsehead - it has been very, very indistinct when I've managed to spot it with my 12 inch and that was with the help of an Hb filter. Certainly nothing horse shaped about my experiences of it !
  14. I can get my 12 inch solid tube F/5.3 dob in my Toyota Auris with one rear seat folded flat plus driver, 2 passengers and a bunch of other gear in the other side of the boot. The Auris (and older one) is about the same size as a Golf so a bit larger than the 106 but not a lot. I've not owned an 8 inch dob for a few years now (2 in the past though) but when I came across one in the window of a photographic store last year I remember thinking how compact and dainty it looked One key phrase in the original post sticks out for me though: "....For the amount of money I know I'm going to need to spend on a setup like this, I'd like better views than I can currently get through my Dob...." So I reckon a 9.25 or 10 inch SCT might be required. And that is certainly not going to be a featherweight affair.
  15. Not much difference on the planets but for DSO's the additional aperture of the 150mm 6SE has some benefits. These are added to by the fact that the 127 mak-cassegrain actually operates at an effective aperture of around 119mm / 120mm rather than the full 127mm. 30mm of difference does make a difference on these fainter targets.
  16. Actually I will have one resolution - get the year right ! ( I don't think I want another re-run of 2020 )
  17. Those that use binoviewers often say that they don't need to use such expensive eyepieces with them to get excellent views. If you get on with these devices they do seem to help tease that additional planetary / lunar / solar detail out. Not sure they help much with deep sky objects though They don't double the effective aperture of the scope though. The light that the scope gathers is split between the two eyepieces reasonably evenly with a small loss of light overall. I think it is the power of using both eyes plus what the brain can do with that information that makes the difference.
  18. I've just found a small aluminum eyepiece case a bit like @Jiggy 67's that is empty currently. I'm going to re-design it's interior layout to make it suitable for filters of different sizes and maybe one or two other things. I'll post the results of the above when I have something to show. Thanks again for all the suggestions and feedback
  19. I think a lot of people buy SCT's because they see a lot of them in use, often within societies. Within the astro society that I belonged to most of the members who had scopes had SCT's. Personally, I've owned a few SCT's up to 8 inches and observed with them up to 14 inches in aperture. I've not been overwhelmed by the views from them generally speaking. I don't image though, just a visual observer. Happy to stick to newtonians on dobsonian mounts and refractors over the past few years. I'm sure the SCT has it's place in the hobby for good reasons though. I know quite a few of our members in this forum have been very happy with theirs. I'm sure they will be "chiming in" soon
  20. That's a C5+ I think. This web page gives more information (lots more !) on this model and includes a working link to the instruction manual: http://www.astronomycorner.net/c5plus/ The site also links to other sites which may be of help. Welcome to the forum by the way
  21. I've often wondered why maksutov-cassegrains are able to deliver such sharp and high contrast views given their relatively large CO %'s. I have assumed that there must be other properties within the optical system and perhaps the lack of secondary support vanes that overcome the CO % size and allow them to excel in this role I used to have a 150mm F/6 mak-newtonian made in Russia by Intes. 19% central obstruction on that one. Not the same sort of "mak" that is the subject of this though. Mak-newtonians are not "folded" to the extent that the maksutove-cassegrain is.
  22. I'm sure that I broke all the ones that I made last year so probably best not to have any resolutions for 2020
  23. Do you mean just one filter or two filters of the same type Mark ?
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