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Posts posted by John
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1 hour ago, mikeDnight said:
I dont have the money, but id soon find it if there was a chance of getting a few ZAO's even though I haven't as yet looked through one.
I have used the AstroPhysics Super Planetaries many years ago on my FS128. The AP eyepieces belonged to a friend, and on one good night when Jupiter was high in the sky, we compared my then TMB Super Monocentric's against the AstroPhysics Super Planetaries. The difference in performance was jaw dropping, with the APSP's soaring ahead in high contrast, high definition performance; and they were noticeably more comfortable to look through. The difference in superior image quality was stunning. I'd find the money for the APSP's too if anyone was insane or desperate enough to sell a set, preferably one at a time.
Thats interesting Mike
I've read a report somewhere where the opposite result occured from a similar comparison.
I'm sure you and your friend saw what you saw and that the other folks saw what they saw as well.
I've given up swapping around eyepieces now. I have what I have and I'll try and get best out of them as the conditions allow. I think I've come to the conclusion that seeing conditions are a larger determining factor than the eyepiece. Observing experience helps a lot as well.
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Hello and welcome to the forum.
What aperture is the main mirror on your seben scope ?
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It is worth bearing in mind that the original review by Alan that kicked off this thread was posted 7 years ago.
I'm sure there are many examples around of scopes and other equipment that were "king of the hill" 7 years ago that have now had their capability exceeded by more recent products.
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1 hour ago, Adam J said:
FPL55 and FCD100 are both harder than FPL53 and the increased hardness makes it easier to achieve a precise finish and shape. Also its not all about the Crown its about the flint too and although FCD100 is slightly more dispersing than FPL53 I have heard it said that the flint glass better matches its properties and so the combination of the two glass types may actually out perform FPL53 combinations. In theory the same may be true of FPL55 but my guess is FCD100 is being used here.
I believe Astro Physics have used FCD100 in their latest incarnation of the Stowaway triplet ?
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There is extensive data here on eyepiece specifications compiled and updated each year by Don Pensack in the USA. Don knows a lot about eyepieces !:
https://www.cloudynights.com/topic/657524-2019-eyepiece-buyers-guide/?p=9288710
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The issue with FPL-53 at one stage seemed to be its continuing availability - there were rumours that Ohara were going to reduce or phase out it's production. But since then I've seen quite a few new scopes coming into the market which specify at least one and sometimes more FPL-53 elements and some in quite large sizes so it seems that, for now, the future supply of FPL-53 is secure. Its price though will be of concern to the manufacturer of lower priced ED refractors - As of 2017, FPL53 glass cost around 20% more than FPL-55 and nearly 100% more than FPL-51.
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I have a couple of less expensive UHC filters as well as the Lumicon O-III - a Meade 4000 Nebular (spelt like that !) in 1.25 inches and the Explore Scientific UHC in 2 inches. Both do make a difference and have quite generous band pass widths so the effect is much more subtle than the O-III. Most of the time though I'm wanting the filter to give a good "kick" to the contrast of the nebulosity and the O-III is by far the best for that.
This illustration of the impact of a high quality O-III filter is not an exaggeration on a darkish night:
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Not wanting to question Suiter of course but I have seen a noticable improvement in the star test before and after getting the tilt of the objective lens correct. Most of my refractors have been slower than F12 though. Usually F/10 or faster.
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For visual use I recommend either the Lumicon, Astronomik or Tele Vue Bandmate II O-III filters. They are expensive but I've tried a lot of filters over the years (including the Baader visual O-III) and the are simply the best performers with the most significant visual impact on the nebulae.
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21 minutes ago, paulastro said:
John said:
It is interesting that Skywatcher heavily promoted that they used an FPL-53 element in the Evostar ED doublets from when they were first released over a decade ago. Not so shy about that back then ?
I may be mistaken, but at the time the original 'champagne' coloured EDs came out, I don't recall there being many other FPL-53 lensed refractors available if any,? If this is the case then it was probably a good marketing ploy. Having said that, the performance at their price point back then was so revolutionary that they didn't need hyping.
The earliest Synta / Skywatcher branded ED doublets had blue tubes. They switched to the champagne / cream colour scheme when the ED120 was launched sometime after the 80 and 100.
The specs also claimed that the objectives were hand finished but that is a loose term that could mean a lot of things !
Back then the rivals didn't seem to specify glass types used unless it was fluorite so its not easy to tell what was used in the few non-fluorite ED doublets around back then.
Back to today and the challenge that Skywatcher face is:
- Forums extensively discuss the minute details of specification and rumours (correct or incorrect) travel fast. I believe this does influence customer demand.
- There are many competing brands who do specify the glass types used.
- We are used to increased levels of information regarding products and regard a lack of such detail as suspicious rather than meritorious.
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The Meade Polaris is basically the same scope as the Skywatcher 130p but with a single axis motor drive included. Made by the same manufacturer (Synta) I reckon.
I agree with the wisdom of buying from a reputable astro dealer such as First Light Optics.
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4 minutes ago, jam1e1 said:
whats the view on having this as a replacement for the Skytee2? ie im thinking of getting one to replace that...plus maybe AZEQ6 replacement also.... would anyone that's used it see a need to keep the ST2 if had this?
The AZ100 is a lot heavier and more solid than a Skytee II, is better engineered and has a higher capacity. It's a lot more expensive as well of course. @Stu knows the AZEQ6 well and can comment on how that compares with the AZ100 I'm sure.
Personally I would want to hold onto a lighter AZ mount as well though so I would have held onto either the Skytee II or the Ercole. Not sure which would have got the vote but its academic because I'm not purchasing an AZ100 !.
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Have you checked that your focuser optical axis is accurately aligned with the optical axis of the objects lens ?
Thats the first check to make. I use an accurately collimated laser collimator to do this check. Put it in the focuser without a diagonal in place and see where the laser beam exits the objective lens. If its right in the centre, all is OK. If it is off to one side or other, the focuser alignment needs adjusting.
When you are confident that the focuser and objective optical axis are aligned, then you can use the cheshire to check objective tilt.
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Its funny how threads and posts get truncated by the "Recently Posted" preview pane. Peters last post comes over as this. Poor Helen !
By Peter Drew · Posted 8 minutes ago
You can always smear some Marmite on them if they're too sweet for you Olly. 😃- 1
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3 minutes ago, Whistlin Bob said:
Apologies- I've just re-read your original post and you're looking for targets, in which case I'll defer to John's advice!
Your additional tools suggestions are good ones
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Hi Popeye,
This is a good web article on star hopping which includes advice on method, tools and some targets including star maps:
https://britastro.org/node/12846
My favourite star hopping tools are:
- The Sky and Telescope Pocket Sky Atlas
- A red torch to read the above
- A zero magnification finder such as a Telrad or Rigel Quickfinder
Here is a link to a more in depth and challenging set of hops to aid a messier marathon by Rob Hawley:
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I don't know exactly what the figure is but the Baader Q-Turret 2.25x barlow increases the eye relief by around 30% I believe.
All the 1.25 inch Hyperions except for the 24mm have optical elements within their 1.25 inch barrel sections as I recall. I'm not sure about the Explore Scientific 68 degree range. If you ask a specific question on this in the eyepiece forum I guess those who own them will give you the information you need.
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44 minutes ago, paulastro said:
If I look through a refractor and it gives me a view I'm happy with, I don't give a fig what glass it's made of ☺
I have read very mixed opinions on that since Skywatcher decided not to state what glass types they use. Personally I would like to know this information but I also understand that it is just one factor amongst many that determines how a scope might perform.
It is interesting that Skywatcher heavily promoted that they used an FPL-53 element in the Evostar ED doublets from when they were first released over a decade ago. Not so shy about that back then ?
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I think that ad might be referring to the highly praised original Evostar ED Pro, ie: this one:
https://www.firstlightoptics.com/pro-series/skywatcher-evostar-80ed-ds-pro-outfit.html
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4 hours ago, Fozzie said:
...Thanks for the heads up, I agree perfect way to kick start 2020 asto..
Assuming that Betelgeuse does not go supernova before the 10th of course !
Even that would probably be clouded out with the weather that we have had lately
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Crab nebula expansion has been captured:
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Just a quick "bump" to this topic because Bristol Astronomical Society are running another Young Persons Astronomy Course starting on Friday the 28th February for 4 weeks. Here is a link to the Eventbrite booking page:
https://www.eventbrite.co.uk/e/young-persons-astronomy-course-9-11-tickets-88371731227
Eyepiece quandary
in Getting Started Equipment Help and Advice
Posted
Good point Raph
I use a Rigel Quikfinder with my 12 inch dobsonian alongside the 9x50 optical finder. Its a great zero magnification finder but it wont find things itself !