Louis D

Back on topic, I would recommend a 2x Barlow simply because I've found them to be more usable on more occasions than 3x Barlows.  I can't remember the last time I used my 3x Barlow.  It got so little use, I retired it to a box of little used astro accessories.

As for the type, the GSO 1.25" 3- element 2.5X APO Barlow lens is affordable and well regarded.  Most reports peg its actual magnification at around 2.1x to 2.2x.  It's also sold as Apertura, TPO, TS Optics and Revelation Astro.  I've read @John much prefers the Baader 2.25x Q-Turret barlow, so I would defer to him on this point.

My personal favorite is the 1990s Meade 4000 140 APO 2x Barlow.  It's also a three element design.  However, it has a removable optics section that can be threaded onto eyepieces for lower magnifications of around 1.6x.  I've measured it to be closer to 2.4x when used as designed.  They come up quite often here in the US on the astro classifieds for $40 to $50.  They might show up second hand on your side of the pond as well.

I'm a bit of a contrarian on the ST-80.  I say just avoid them.  I've had one for 20+ years, and have hardly ever used it due to the excessive CA (chromatic aberration) and SA (spherical aberration).  Views through it are highly unsatisfying.

I would highly recommend a 72ED on an alt-az mount instead.  The wide views are astoundingly sharp and satisfying through them.  They are also extremely compact and relatively light.  I really love that they come with 2" focusers for extremely wide views.  They allow you to see the sky in an entirely different way from your 8" Newt.

If you trend toward higher power viewing, I would recommend a 127 Mak.  They can be mounted on the same mount class as the 72EDs, so you can swap them depending on your observing mood.

49 minutes ago, AlexK said:

As even a slight jitter of the view at a high magnification when you are guiding

However, I've noticed that when binoviewing, lightly tapping my Dob's tube at high power can sometimes allow me to recognize fine details more easily for the same reason it is easier to see a camouflaged animal in motion than when still.  It spuriously kicks-in my brain's motion processing centers.

41 minutes ago, johninderby said:

In other words get your Bresser order in now before any price increases.🤔

I was thinking the same thing.  Bresser is sure to follow with a price increase in the near future.

C-19 in general has lead to rapidly increasing prices for both durable and non-durable goods across the board.  However, I have yet to hear of it being flagged as a concern by the media or politicians.

I might have missed it being recommended above, but I highly recommend getting a bottom cap/cover for the tube.  It's surprising how much dust can drift onto the mirror from the gaps around it at the bottom end of the tube.

That's wild it doesn't come with a 2" to 1.25" reducer.  I had assumed they came standard with all ED/APO refractors.  Both of my ED/APO refractors (AT27ED and TS 90mm APO) both came with them.

It shouldn't be a big deal to locate an aftermarket adapter.  Just make sure it is robust enough to resist the torquing of an eyepiece in a 1.25" diagonal.  This means you'll want a decently long 1.25" sleeve inside the adapter.  I've tried using a 2" to 1.25" adapter from a 2" diagonal for this, but it wasn't really up to the task.

Just remember to always put the fluid on the cloth, not the object to be cleaned.  It can wick around the edges and get to inaccessible surfaces.

The QuikFinder will pop off if you catch it on the door frame while carrying the scope out.  Being so light, it will just clatter harmless to the ground.  How do I know this?  I've done it a few times.

The Telrad is quite firmly attached with screws to the base and won't come off if caught on a door frame.  It is robust enough, though, that I've yet to have it break because of it.

I use both.  I prefer the Telrad when space on the scope allows it because the circles are thicker, easier to acquire, and go out to 4 degrees.  The QuikFinder circles are really thin, can be a pain to locate in the window, and only go out to 2 degrees.  However, it's really the only good option for small scopes.

I mainly use my zooms in my binoviewer because it's a pain to swap two eyepieces instead of one and to make sure each is seated square to the holder so the images will merge properly.

In the central 50% of the view, most zooms perform about as well as Starguiders in my recollection.  It's at the edges that they start to lose out a bit on clarity.  That, and the field stop is sharp only around the middle of the range.  It grows slightly fuzzy toward both ends.  Not everyone is bothered by this, though.  In a binoviewer, you can't really look too far off axis without losing one or the other view, so that lack of absolute outer field clarity and field stop sharpness is in peripheral vision anyway.

If you're on a budget, I would recommend the BST Starguiders, especially at the 5mm to 12mm focal lengths.  They have good eye relief, good correction even in faster scopes, and a 60 degree apparent field of view.

For zooms, either the 7.2-21.5mm or 8-24mm varieties are fine.

44 minutes ago, Spier24 said:

The community seems quite friendly but I can see what you mean about the snobbery, the most common things I see from that is people getting scoffed at for wanting or owning a GoTo scope. Personally I think GoTo scopes are a god send in light polluted areas as star hoping isn't easy there, especially for a beginner. I live in a Bortle 7 area and have never owned a telescope before so a GoTo is a must for me.

There are other options such as DSCs and even manual setting circles for finding objects in bright skies.

Gotos are fine once they're aligned, but too many beginners are put off by the difficulty of some (older) systems.  There are newer ones that align themselves using plate solving, which is terrific for beginners.  The problem is, how to get a newbie into a decent sized telescope with plate solving goto for under $200 to $300 (the typical beginner budget).  It's a different discussion when their budget is $2000.

39 minutes ago, ScouseSpaceCadet said:

The AZ5 is a brick though

At 5 pounds, it doesn't seem that bad.  My DSV-1 weighs just about the same, and I consider it fairly light weight.  My DSV-2B at 9 pounds feels considerably heavier.

I would agree that the 127 Maks are good for light weight, compact setups.  I've got one and I bought one for my daughter for her camping trips.  The scope and all the gear fit in a gym duffel bag.  The mount and tripod fit in a long tripod/light stand bag.

The Synta 127s are really only 118mm in clear aperture, so the OP might want to look at the Bresser/ES 127 which is supposed to accurately rated.  The advantage of the Synta Maks over the Bresser/ES Maks is that they show up regularly in the classifieds for $200 to $300, at least here in the US.

Here's @Geoff Lister's posting about putting an entire 127 Mak and goto mount into a backpack minus the tripod:

I've repeated the image below:

To reduce weight, but not sacrifice rigidity, the AZ5's tripod could be replaced with a carbon fiber photo tripod.  It would also dampen vibrations better than metal as well.

9 hours ago, wookie1965 said:

I had a 200p on a EQ5 goto never had a problem with it I did have a Telrad on it and I had two rings so I could spin the tube so the focuser is in  easier position to see into. 

Is it possible to observe while seated using this setup?  It seems like it would need a really tall observing chair.

2 minutes ago, Laurieast said:

No, nothing, I bought the entire telescope with cast iron mount and clockwork drive from a farmer in Lancashire for £10 about forty years ago. 

And that farmer's probably dead by now, so no help there getting more history on it.

It would help immensely if you had any provenance papers for it.

23 minutes ago, callisto said:

Aww....Very cute

I looked it up, and now I want one if I can find one for cheap.

It turns out TOMYTEC still owns Borg:

I think this might be the part you need: Baader 2" ClickLock M56i Clamp (Takahashi)

Check with FLO, they'll probably be able to help you decide.

14 hours ago, theropod said:

My 60mm DIY refractor. Only able to test on terrestrial targets, but so far so good. The oversize dew shield really knocks out side glare, and I’m not sure it will be of much use against dew but I’ll see when warmer nights come back. Using it freehand, and braced against my house, it really made M42 pop. If the stinking weather ever permits I’ll give it a good test on some faint fuzzies.

I did test out my SV105 with this scope today, mostly messing around with Sharpcap, and I’m pretty pumped to get a couple hours under clear skies to push the envelope. M1?

The FOV is so much wider than my C90, but the apparent magnification seems very close. Maybe this will make those 1, 2, & 3 star alignments pretty easy by comparison. My EQM 35 ought to act as if there wasn’t even a scope mounted, except for maybe wind issues, but as light (<1k) as it is I’m not worried about that too much.

The objective (formerly from binos) really came to life after I removed the prism stack, and the upside down view doesn’t both me near as much as I thought it would. Sharpcap makes that a non issue. 

 

When I saw the radiator clamp, I knew you had to be an American.  I've got one holding together some splitting wood on my Adirondack rocker.  It can be added to the list of duct (duck) tape and baling wiring for fixing anything.

On 28/01/2021 at 14:00, Nicola Hannah Butterfield said:

my rifle, (tripod slung over shoulder)

It always surprised me I never got challenged for carrying my "rifle" (tripod in a long soft case) into school auditoriums for performances.  I guess everybody knew I was the guy with the large video tripod.  I also always had a large still and video camera case over the other shoulder.

Does anyone know why the UK has a £39 personal importation limit compared the US's $800 daily limit?  It's such a huge disparity that it's hard to believe it exists.

On 31/01/2021 at 17:30, Dantooine said:

I’m surprised nobody’s mentioned laser finders. 

On 31/01/2021 at 17:40, JeremyS said:

What about laser finders? 🤣

Yeah, there seems to be a general aversion to them on SGL as compared to CN.  I love my cheapo ebay laser sights.  One is permanently mounted on a Picatinny rail on my Dob while another is on a Vixen/Synta finder foot to Picatinny rail adapter for use on the refractors.  I even have one permanently mounted on my DSV-1 mount's handle via the barrel adapter that comes with them.  I still keep a Telrad or Rigel mounted for when the rechargeable battery goes south during an observing session.  Lasers are great for those of us with neck and back injuries.  They also rule for use near zenith.  There's also no debate about using them with one eye or two eyes open.

15 hours ago, vlaiv said:

we could say that it faster goes up and down and that it has steeper curve when it goes thru 0.

In digital electronics, we generally refer to this as the slew rate.  The higher the slew rate, the steeper the curve transitioning from 0 to 1 or 1 to 0.

And an improperly cleaned mirror with added microscratches on the surface is worse for scattering than some random dust and sap that doesn't redirect light nearly as well as scratches.

Ever looked at the clear coat on a car washed regularly versus one infrequently cleaned?  Up close (get out a loupe), there's lots of fine scratches in the clear coat finish of the regularly washed car.  The infrequently washed finish will have much fewer microscratches in comparison.  It may have etching from acidic bird doo left on it too long, but it will have much less fine scratching.  That's why claying fine car finishes is popular because it lifts the crud off straight up reducing the opportunity for scratching.

16 hours ago, Don Pensack said:

The original versions of the Meade Series 4000 UWA eyepieces had some issues:

1) apparent fields actually quite a bit smaller than claimed--more like 76-78°

2) serious spherical aberration of the exit pupil.  This bothered the 14mm more than the shorter focal lengths, but it was present nonetheless.

3) some actually uncoated interior lens surfaces.  I took my set apart several years after getting them to clean interior surfaces and blacken lens edges and was shocked to see that.  Explains Louis's comments.

4) some shiny spacers that were very much improved by blackening with flat black paint.

It's highly likely these were made by Kowa, the manufacturer of the 5-element S.4000 "Super Plössls" and the S.4000 SWAs, which would explain the high polish on the lenses.

 

I think I'll leave mine be as an "unrestored" collector's piece and just use the 14mm Morpheus day to day instead.  No amount of blackening will fix the SAEP, uncoated lenses, and slightly tighter eye relief.  I just get a kick out of looking through it and marveling at what was accomplished nearly 40 years ago with that eyepiece.

16 hours ago, JTEC said:

Both Baader-Zeiss prisms perform beautifully in my scopes (TEC140 and C11) at all useable mags.  Visibly less scatter than the ‘best in class’ AstroPhysics Dielectric I previously used, and sold. No discernible unwanted colour whatsoever at these focal ratios (f7 and f10).  Work perfectly with binos, where same applies. BillP seemed to prefer the 1.25 prism slightly over the 2” for planetary views. Can’t say I really notice any difference; that said, my best ever planetary views have indeed been with the TEC, Zeiss-Baader binos and the 1.25 prism.  

Not surprising.  Dielectric coatings are known to have a certain surface roughness absent in prisms and even silver coatings.  I wonder if the BBHS dielectric protective overcoat ruins the smoothness of silver.