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Observing with Small Apertures: 130mm and Below

Discussion in 'Telescopes and Mounts' started by Ray of Light, Jul 26, 2016.

Observing with Small Apertures: 130mm and Below

Started by Ray of Light on Jul 26, 2016 at 5:34 AM

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  1. Mak the Night

    Mak the Night Well-Known Member

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    I'm pretty sure a lot of Zhumell, Levenhuk and others are just rebadged GSO, Barsta etc. I'm convinced Orion, Sky-Watcher and many Celestron Plossls are Barsta. Don't know about the Celestron Omni series though, they seem different.



    I have a suspicion that not all of the TMB lookalikes are actually Barsta/BST. I don't think there's any difference in quality though.
     
  2. Dave In Vermont

    Dave In Vermont Well-Known Member

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    I wrote to Agena about when they might know about getting those in. Got a letter back in about an hour! They wouldn't have known about such for 8 - 10 weeks. So no loss in my choice of an Astromania in my EP-Cases. LOL!

    But I may well get some others from Agena if/when they do actually get some in. Tom at Agena just gave me a crash-course in buying & re-stocking from a Chinese distributor. It pretty much sounds like this:

    "It's like a box of chocolates. You never know what you're going to get!"

    I'm actually NOT kidding. It does work like that. They don't know what will be in their order until they have it in their hand.

    DR
     
    Last edited: Sep 5, 2017
  3. Mak the Night

    Mak the Night Well-Known Member

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    The box of chocolates thing sounds familiar. It could explain 365Astronomy's pot luck lottery approach to these eyepiece types particularly.



    I got these two EP's from 365Astronomy for 36 quid (46.65 USD) apiece. The 4mm on the left is definitely Barsta/BST. I'm not so sure about the 4.5mm on the right. It is different in many ways. The housing has a matte rather than gloss finish. The dimensions/proportions and overall finish seem very slightly different. The eye lens and field lens caps are different (the 4.5mm shown actually has an old Barsta eye lens dust cap now as the original was very loose fitting). The draw tube has a slight flare rather than an undercut. In use it's just as good as the TS Optics though.

    365.jpg

    Oh yeah, more filter pr0n ... the 2" UHC-S arrived.

    filterpr0n.jpg
     
    Last edited: Sep 5, 2017
  4. Dave In Vermont

    Dave In Vermont Well-Known Member

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    I see you got the inference. :p

    Having a lovely day here in the Untied Snakes! Watching the riots about to break out - fueled by a lunatic-savant!

    Back to stitching-up my old Kevlar® Body-Suit before I take a stroll to the grocery...



    Apropo,

    Raul (for the Duration)
     
  5. Mak the Night

    Mak the Night Well-Known Member

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    Things can only get better!



    There's a Full Moon tonight, looked a bit hazy through the little Mak.
     
  6. Mak the Night

    Mak the Night Well-Known Member

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    Saturn Titan.jpg

    Got a butcher's at Saturn in twilight until about 21:30 BST with the 90mm StarMax. As it got darker I could occasionally just about make out Titan. I didn't know it would be to the right of Saturn, but I figured it had to be Titan. This CDC shot more or less confirmed it.
     
  7. Dave In Vermont

    Dave In Vermont Well-Known Member

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    You're the Master of Carte du Ciel here, Mak. So you'd know if CdC's lunar-positions are accurate. But I do know that Stellarium makes much of the fact that their lunar-positions for the outer-planets are spot-on. I'm sure you can find out about CdC with too much trouble. And Alex is lurking about and does respond if you ask him a question. Remember - the Stellarium-team is colluding (I L*O*V*E* how that word rolls off the tongue! Though it's being over-used to describe the pernicious and illegal actions of a certain walking-form of human toe-fungus...) with CdC presently. So I can be pretty sure that CdC also displays accurate data on lunar-positions.

    Maybe you could write a letter to the developers of CdC and invite them into this forum? That would give this place a new 'feel' that would leave those untrained twits in the Dark Lords' Manor in the weeds! :p By-the-by, it appears my letters to the admins had a positive affect. The worst-of-the-litter has been avoiding Yours' Truly utterly un-molested. They won't even chime-in to threads I'm involved with. There's a hilarious thread on slugs & maggots everyone is reading. And not a peep out of the worst-of-the-worst. Normally they'd have deleted the thread, considering the contents. It must be killing them! :D

    It's been pouring rain here in Podunk. Of course. This as we're well-positioned for a good aurora-borealis following that massive solar-flare. I'm sure it would be a great display though, and cynical-me can be certain by seeing rivers-of-rain pouring out of the sky at present. I wonder when we'll get a hurricane? Had one a few years ago that devastated us, so Vermont is quite vulnerable now. It would have been regarded as unheard of a few short years ago. Now we're on the charts for hurricanes AND tornadoes, too!

    Ciao,

    evaD
     
    Last edited: Sep 8, 2017
  8. Mak the Night

    Mak the Night Well-Known Member

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    In my experience CDC is pretty accurate about everything. Sadly, Stellarium isn't. Unless they've fixed it. I'm still using version 12 (on Ubuntu) but I won't run it on Windows anymore.

    M42 1.jpg

    I just got a three hour break in the clouds and have been observing the Moon from about 02:00 to 04:00. Not the most exciting phase but I got a very clear 300x with the 6mm Vixen NPL combined with a TV Barlow. The Vixen's such a star, it blew the 6.4mm Meade away. If TV made a 6mm Plossl it wouldn't be better than the Vixen.

    M42 2.jpg

    I was using the 130mm Newtonian and decided to compare the 1.25" Baader UHC-S with the 1.25" Astronomik UHC-E on M42. As you know, I recently bought a 2" UHC-S to compliment the 2" UHC-E for my ST80. I was fairly convinced that the UHC-S would work better on emission nebulae. I wasn't wrong and it provided a more natural view revealing more of the nebulosity than the Astronomik. I also tried the TS UCF1, a Baader Neodymium and the Semi-Apo. The Semi-Apo was the most yellow lol. All of this was with a 30mm Vixen NPL giving 30x exactly. Naturally, the best view of the night was with the 19mm TV Panoptic and a Baader Neodymium for about 47x. I even went to 150x with the 6mm Vixen NPL. I really need to sleep now ... zzzzzzzzzzzz ...
     
  9. Dave In Vermont

    Dave In Vermont Well-Known Member

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    Oh by the way - in 'lunar-positions' I was alluding to, I meant the Moons of the outer gas-giants, such as Titan and the rest of the retinue. And Stellarium has added quite a few of the lesser-known Moons of Saturn and Uranus. No doubt Neptune is in the works - if not done already. In the latest 'trunk' version of Stellarium I've grabbed to check-out, the Moons of Pluto have also been added & updated. Quite nice! As well as fascinating to me.

    No argument regards Vixen EP's! I've been a fan of these since around 2002 since the first of the first Vixen LV crawled into one of my eyepiece-cases. I never looked at TeleVue® Plössls again. Considered sacrilage in the Dark Lords' Manor!

    evaD
     
  10. Mak the Night

    Mak the Night Well-Known Member

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    I'm sure they're making a good job of Stellarium. The GRS position has been out for ages though. Have they solved the BIOS clock resetting bug yet?

    If TV made a 6mm Plossl or even a short Barlow I'd probably buy it. The Meade 6.4mm is a nice Plossl and I was getting around 281x with a Barlow. The images were good but when I changed to the Vixen 6mm NPL for 300x exactly I really thought the images were slightly sharper. It might have been rapidly fluctuating conditions but it was noticeable. Mind you, the 6mm NPL has hardly 3mm of eye relief, which might be a factor in its performance.
     
  11. Dave In Vermont

    Dave In Vermont Well-Known Member

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    I wouldn't know about such with Stellarium, but you could always drop a question to Alex Wolf, you know? He does answer them.

    Here's the Vixen LV's from around 2001 I got a few of:

    Vixen LV EP's.jpg

    If I'd known they'd disappear soon after I bought mine, I'd have bought the full set (of about 20 or more!). Though only about 45° - 50° FOV, they gave the impression of being wider. They just 'felt' that way (still do). And totally sharp edge-to-edge. Superior to Plössls anyday in my book. Plenty of eye-relief too. The lanthanum-element is magic!

    I know you'd have hated them though - just look at that under-cut on the barrels! Tsk! Tsk! :eek: :p

    I'll go away now...

    evaD
     
  12. Mak the Night

    Mak the Night Well-Known Member

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    I'm pretty sure they haven't fixed the Stellarium BIOS clock bug. The good news is that it works perfectly on Linux. I've been looking at the LVW's, their undercut isn't too bad. Undercuts can be a real PITA when you can effectively only use one hand lol. They can be the cause of much profanity in the dead of night!
     
  13. Dave In Vermont

    Dave In Vermont Well-Known Member

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    I had my fun of being one-armed after I fell down the stairs. Broken shoulder was no fun at all, and it came part & parcel with losing the use of my right-arm & hand in the bargain. Only now is full-use returned (mostly). When I had a broken fibula, I was in a wheelchair - for a long enough period of time to learn how to drive it with the best of them! Downhill high-speed runs was fun - after I had learned to drive the thing with a high enough level of competence to feel comfortable just 'letting-go' and enjoy the ride. Rather than being in a state of abject terror! :eek:

    Zen and the Art of Wheelchair - Racing.....

    My nocturnal swearing was developed as a reflex to being slapped in the face (always the exact same place - my left cheek just below my eye and above my fur) by a near-sighted Bat. I really didn't mind - it was taking out the mosquitoes - but it was reflexive to the combination of the sound (whoosh - SmAcK!) and the feeling of a leathery-wing against my skin in the darkness. So I'd let out a loud swear and the following statement: "See an optometrist!" My neighbor's were used to me.

    My neighbors' Cat, 'Bear,' finally got the Bat. A Cat that can catch a Bat is one FAST Cat! He and I were good friends!

    So I truly can empathize with your situation, Mak. But one does adapt rather quickly, in my experience at least.

    evaD



    vampire-bat.jpg
     
  14. Dave In Vermont

    Dave In Vermont Well-Known Member

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  15. Mak the Night

    Mak the Night Well-Known Member

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    I'm glad your arm is better Dave. I'm making some progress myself and I can do things now I couldn't a year ago. I get hedgehogs, bats, cats, foxes, badgers and owls, although none of them slap me. The foxes dig holes which are dangerous for me. The cats are the main problem, there are about 27 in my street alone. Most of them use my garden as a toilet. One little basket even sprayed my EQ5 once! That was the final straw and I took drastic measures. Including lion dung pellets and these:

    c3.jpg c4.jpg mc3.jpg mc4.jpg IMG-20170825-00195.jpg IMG-20170825-00197.jpg

    I just don't see them really now lol.

    uhc-s 40 32.jpg

    I’ve been thinking about the efficacy of the UHC-S and UHC-E on the ST80. The UHC-S is basically a broadband filter and the UHC-E is a wide narrowband. I’m still not totally sold that full narrowband filters can be used effectively on reflectors under 150mm and refractors under around 100mm. I know that there are claims that they can but I think this has a lot to do with the focal ratio of the scope being used. I experimented observing M42 with the 1.25“ UHC-S using 32mm and 40mm Plossls this morning. I should have used both Celestron (Barsta) Plossls for the sake of pedantic scientific consistency (lol), but I took the Revelation (GSO) out accidentally.

    The 130mm Explorer is f/6.9; giving magnifications of 28.125x and 22.5x respectively with the 32mm and 40mm Plossls. The exit pupil for the 32mm is 4.6mm and the 40mm gives 5.7mm. Although the conditions weren’t perfect, with a bright high Moon, below average transparency and 2~3 Antoniadi, the view of the emission nebula with the broadband UHC-S was significantly better I thought using the 40mm Plossl. Although the magnification was 5.6x less I perceived more of the nebula cloud and it seemed to have better definition. The 40mm is basically giving me a little over twenty times the magnification of the unaided eye. Yet the 32mm is more or less giving me nearly thirty. I believe that this is significant and the nearer to a 6 or 7mm exit pupil I get the better.

    The 28mm LET will give me a 5.6mm exit pupil for about 14x and the 36mm Hyperion will give 7.2mm for around 11x. It will be interesting to try these on M42.
     
  16. Dave In Vermont

    Dave In Vermont Well-Known Member

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    Sounds good re: 40mm & UHC-S. Me thinks I'll give that a shot, too. I have a UHC-S in my filter-case. Still debating the UHC-E though. As for a 40mm Plössl, I have an excellent one of these, too. One of my favorite EP's actually. Another slap-in-face for the"Green-Letters-Only!" crowd. :eek: :p

    The Hurricane appears to be down to a Cat. 2, which makes me feel conflicted. A fascist radio-scuz over here, Rush Limbaugh, told people not to evacuate, the the hurricane was a "Liberal-conspiracy fake-news...." They propagandize ALL science as lies. So in one way, I'm sad tosee Irma didn't blow Florida off-the-planet just to show his listner's this guy is a dangerous liar!

    On the other hand, I'm glad people haven't been badly hurt by the damage sustained...

    https://www.democraticunderground.com/125118332

    (Find off this link - play "I'm a Nazi."


    'Ta,

    evaD
     
  17. Mak the Night

    Mak the Night Well-Known Member

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    I used the 40mm Plossl as it's the longest focal length I can use on the Explorer. I literally don't have anything with a longer focal length. As I was primarily observing the Moon the 'Bazooka' was already set up so it was easier to experiment with that than set up the ST80.

    I've decided not to buy a dedicated 2" narrowband filter. The Orion UltraBlock 2" seems impossible to get over here. I don't know how useful the UHC-E will be on my ST80 but the prospect of a relatively inexpensive comet filter was too much to pass on. I saw Johnson with the 1.25" UHC-E and the ST80 before I replaced the focuser. The UHC-E is also very good on Jupiter, especially in twilight and dodgy conditions, where it really emphasises cloud detail and the GRS. It's a bit like an #80A on steroids in that respect.

    There is an f/5 version of the Explorer. A 40mm would give 16.25x for an 8mm exit pupil, although whether that would be overkill or not is debatable. I can handle a 7mm exit pupil quite well but 8mm might be pushing it. I'm not sure, but most binoculars (8x30?) have a 7mm exit pupil.

    I was once told on Cloudy Nights that the European Space Agency had a 'liberal agenda'. I'm still a bit mystified what 'liberal agenda' means, as it almost certainly has an entirely different meaning in the UK.

    There is an odd obscurantism with many people at the moment. I don't know what's driving it. Denial of evolution and the big bang seem to be favourites. The statement that 'evolution is only a theory' as if it was some vague subjunctive notion is something I've actually heard people say. I've ceased trying to help the brain dead evolve though. The best thing they can do is off themselves and take themselves out of the gene pool. That actually would improve the race in a Darwinian sense.

     
    Last edited: Sep 10, 2017
  18. Dave In Vermont

    Dave In Vermont Well-Known Member

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    'Liberal' is a word in constant use over here by the believers of Rush Limbaugh in that accurate tune I pointed to. When asked to define it - these people never have an answer regards the meaning. Or they start calling you a "Libturd (or 'Libtard')." Genius!

    The 'gene-pool' being 'cleaned' by prevention of the breeding of the idiots. I'll tell you why I beg to disagree regards the merits of such:

    I had occasion to work with a Harvard professor back in 1977 - by the name of George Wald - on a highly politcalized situation of the finding of Paraquat, which is an extremely carcinogenic weed-killer, to being sprayed on cannabis by the US government - especially on pot that had been seized by the DEA - and then re-sold on the streets to the citizens of the USA (and anyone else with $$$). In other words - to poison pot-smokers and prove smoking it really was bad for you. To our own citizens. The people that the DEA exists solely to protect from harm.

    George Wald had won a Nobel-Prize a few years years earlier in the field of biochemistry. His wife was also a Harvard Professer - in organic-chemistry. And George put his wife in the position of verifying a simple test I devised that anyone could perform on pot to indicate if it had been exposed to this carcinogenic poison. The entire matter would then be voted on by the Cambridge* City Council to allow people to legally carry cannabis to the Cambridge City Hospital to test it there so we could get the proof needed to win a massive Class-Action lawsuit against the DEA for everything from reckless-endangerment to murder.

    All hell broke loose when the city-council voted unanonymously to do so. The federal government then threatened to arrest and jail everyone involved - from the city-council members, the mayor, and the entire police-force.....And me, of course - who was a chemistry-teacher in a high-school, as well as a 17 year old student there. But they didn't go after the Wald's.

    Now the genetic-angle enters this mess as George Wald was approached by a new sperm-bank that wanted to stockpile the 'seeds of genius' to create a 'super-generation' of babies (perhaps in Brazil? :D) George replied to their request in the news-media, which wanted to know what he planned to say in answer to these 'breeders.'

    "You want my sperm? For your information, my mother was cerifiably insane and spent most of her life in a mental-hospital. And my father was violent alcoholic who finally died of liver-disease brought on by his heavy drinking. And you want my sperm?"

    And that was the last time there was any mention of this bunch and their 'Genius Sperm-Bank.' So perhaps your plans for cleaning-up the old 'gene-pool' could stand a bit of re-thought? :p

    No disrespect implied to the theories of Mr. Darwin. Only to the 'Darwinian-Prize Winners,'

    evaD :D


    * Cambridge, Massachusetts - home town to MIT, Harvard, Yours' Truly.
     
    Last edited: Sep 10, 2017
  19. Mak the Night

    Mak the Night Well-Known Member

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    Last edited: Sep 10, 2017
  20. Dave In Vermont

    Dave In Vermont Well-Known Member

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    "Insanity is hereditary. You get it from your kids."

    The ultrasonics? Naw - I'd suspect the Black-Cat Cut-Outs.

    Fluoride in the water? That was a belief the ultra-right-wing used to claim it was a "commie-plot" to put fluoride in drinking-water during the Cold-War against the Soviet-Union. Then I read it was used by the Nazi's to pacify the inmates in their concentration-camps.

    I listened to my dentist, personally. He said it worked great in making & keeping the teeth stronger. Then I read a book on experiments in causing skeletal-fluorosis by having volunteers inhale trace amounts of hydrogen fluoride gas in sealed-chambers. Made their spines warp into something like a Dadaist sculpture. How they ever talked people into 'volunteering' for this 'study' was never made clear.

    Never play Trivial-Pursuit with me.

    evaD
     

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