Louis D

@WavseekerBe aware of how big and bulky the xx12i is.  It weighs 84 pounds assembled and the heaviest component weighs 50 pounds.  If you don't have a decent sized car to transport it, it will only get used from your light polluted backyard.  If you do transport it by car, it will take up quite a bit of space.  This isn't such a big issue in the US if you own a Chevy Suburban, but most cars in Europe tend to be somewhat smaller.

For travel, I would recommend either a 3" or 4" ED refractor or a 5" to 8" Mak or SCT.  Remember that Maks and SCTs have long focal lengths, so you won't be able to achieve low power views of larger objects.  I would start smaller because the smaller scopes tend to get used more.  If you find you like astronomy, then move up to a bigger scope in the future if you want to see more planetary and DSO detail.  You'll still have the smaller scope for grab and go usage.

5 hours ago, Cosmic Geoff said:

Or did you mean do we have experience of Optcorp? They don't disclose their location. That's enough reason not to buy from them.  They appear to be based in the USA, so you should add international shipping, taxes and duties to the price they quote. I'd advise you to buy in Belgium or the EU.

Optcorp is OPT, Oceanside Photo and Telescope.  They're one of the oldest and best astro retailers in the US.  The recently closed their retail store, so now they only do in person visits by appointment only.  They list their new address as 2245 Camino Vida Roble, Suite 102, Carlsbad, CA 92011.

They are now no different from Agena Astro and FLO in having no physical retail presence, so I don't understand why that makes them shady.  You might as well lump Amazon in that group.

As far as taxes and duties, I'm glad Texas doesn't collect sales tax on international sales and the US federal government exempts imports under $800 from tariffs.  What with the current weakness of the GBP relative to the USD, there are quite a few bargains for Americans to be had cross-importing from the UK.  For instance, if I were to buy all 7 BST Starguider eyepieces from FLO, they work out to $40 each with international shipping compared to $60 each bought locally from Agena Astro with free shipping.  Vixen SLVs are also considerable cheaper from the UK.  They're $109 each shipped to the US from FLO compared to $169 each shipped from Agena.

I think even the cheap binoviewers are collimateable.  The screws are under the rubber grips.  However, most folks report no issues with regards to collimation that I've ever read.  The issue of non-merging images is usually due to one or both eyepieces not being held perfectly orthogonal to the eyepiece holder.  Even with a locking collet in each eyepiece holder, eyepiece undercuts can cause eyepieces to tip.  I have to jam my undercut eyepieces down while tightening the locking collet to keep them from tipping.  I've also had issues with merging when rotating the diopter adjuster upward.  That eyepiece's image will circle around the other eyepiece's image until rotated 360 degrees.  This all on an Arcturus binoviewer.

On 08/08/2019 at 10:59, JeremyS said:

And before you know it, you will have 3 cases 🙂

Nice solution, you've come up with.

And then another case for the binoviewer and eyepiece pairs when the binoviewing bug bites.

If you have a 2" focuser, I'd look into getting a 30mm or so wide field eyepiece like the ES-82 or APM UFF.  I enjoy scanning wide field views of rich star fields as much as observing individual targets.

On 05/08/2019 at 03:03, M55_uk said:

older newbies also need a stool /chair, I can confirm

 

I can also confirm that an observing chair is important even for the younger set.  I started observing in my early 30s, and I used a chair from the first day.  It makes observing so much more relaxing.

Now, my older back aches after 4+ hours of being hunched over eyepieces during observing.  It can take several days for it to recover.  Anybody else have similar bback issues?

@daz It's not clear from your initial post if you're open to 2" eyepieces.  It's also not clear if you suffer from severe astigmatism in your observing eye.  If you're restricted to 1.25" eyepieces as your list of possible eyepieces suggests, then that severely limits your maximum true field of view.  I'd invest part of my funds in a decent 2" diagonal in that case.  If you have severe astigmatism and need to wear eyeglasses when using low power eyepieces, then that also plays into the suggestion equation.

My personal recommendation would be a 30mm APM UFF if you can use 2" eyepieces.  I much prefer it to my 27mm Panoptic, 30mm ES-82, and 30mm Widescan III clone for wide field scanning when wearing eyeglasses.

1 hour ago, Scott42 said:

Thanks for setting me straight!  I've used the WIdescans-types before.  So the UFF has some more lenses to flatten things out.   I see that there is no "safety groove" on the APM which is fantastic.   Weight is very reasonable at 19 ounces.

It's actually an entirely new approach to lens design to keep it slim enough for binoscope usage as well as being flat field.  The lowest elements actually form a telecompressor instead of the more typical Smyth or Barlow tele-extender.  The physical field stop (30.4mm as shown in the lens diagram) is smaller than the effective field stop (36.4mm as I measure it based on the above photo) as a result.

You might be able to get away with putting a pop-up cover over your whole rig so it gets good airflow to prevent the heat buildup associated with a tight fitting cover.

Found a European supplier of those 55 degree eyepieces under the Omegon brand.  I've never looked through one, so I can't comment on their relative merits.

Contact user 25585 here and on CN (same ID).  He's the only one I know of with one.  He seems to think highly of it.

There's also the 4.5mm Meade HD-60 and 5mm Starguider BST (Paradigm) if budget is an issue, at least in the US.  I have both and they are very close to my 5.2mm Pentax XL in sharpness.  The Starguider has some overall field of view brightening which wouldn't be a huge issue for planetary viewing.  It's also a bit finicky to find best focus.

I really like the 6.5mm Meade HD-60.  It is just about the same view-wise as my 7mm Pentax XW.  There's very little to choose between them other than field stop sharpness.

Here's the FOV images I took of both lines:

There's the 5mm Vixen SLV which would have a narrower than 60 degree field of view, but plenty of sharpness and eye relief.  It's a bit expensive for your budget, but maybe one might turn up used?  There's also the older LV and NLV to watch out for as well in the classifieds.

8 hours ago, M55_uk said:

Being a newbie myself, I have realised that one important bit that you need to factor in (if you havent already) is set aside some budget for eyepieces & telrad (optional). Hope this helps

 

Add in collimation tools for Newts in particular.  A well collimated Newt is beaten only by an APO refractor in my experience.

While learning the skies, an old fashioned planisphere is handy to have.  Sure you can use phone apps, but the older method helps you to understand the progression of the sky night by night and hour by hour.

For older newbies with presbyopia and strong astigmatism like myself, they might also want to invest in a dedicated pair of distance only eyeglasses to correct their astigmatism across the entire field of view.  This isn't possible with bifocals or progressive lenses.  Luckily, there are plenty of online places that make quality eyeglasses for very reasonable prices.

Other good accessories to invest in are a high quality OIII filter first and a quality UHC filter second, especially if you observe under light polluted skies.

6 hours ago, M55_uk said:

The near end can be turned (unscrewed?) a little bit - I am guessing this is for fine focussing. Is that right?

If by "near end" you mean the eye lens end, that's the twist-up eye cup that can be raised or lowered to help position your eye at the correct distance to take in the eyepiece's exit pupil properly.

6 hours ago, M55_uk said:

Also I read somewhere that this planetary eyepiece comes with a built in barlow which can be removed. Any tips on how to do that?

This is a negative/positive eyepiece design.  The lower part that inserts into the focuser has a Smyth lens which is an integral Barlow lens matched to the positive section above it that actually forms the image seen by the eye.  Without the negative section, you'll have a poorly corrected Konig-like eyepiece.  I wouldn't bother messing with it.

7 hours ago, Scott42 said:

It looks good - not too heavy - and the price is right, I'd like to try one....the body looks similar to the TMB Paragon series.  Only 5 elements and 80 degrees, sounds interesting.   I did like the XW40mm better than the Paragon 40mm but the XW40 is far heavier.

https://www.apm-telescopes.de/en/eyepieces/more-74-ultra-wide-angle/apm-lunt-eyepieces/apm-eyepiece-uw-30-mm-80.html

Wrong 30mm APM.  That's the much older Widescan III clone.  It has severe field curvature leading to blurry edges.

This is the 30mm APM UFF I'm referring to.  It has 9 elements in 5 groups:

I did compare it to the Agena Astro version of the 30mm Widescan clone in this thread.  If you page down, I have several comparison reports.  Here's what they look like side by side.  The 2nd eyepiece from the left that says 20mm is really a 30mm Widescan clone that comes with a removable barlow element to make it 20mm.  The 3rd eyepiece from the left is the APM UFF.  The leftmost one is a decloaked original 30mm ES-82 when they had a twist-up, mushroom shaped eye guard.  The 27mm Panoptic on the far right is self-explanatory.

And this field of view comparison image includes all of the above eyepieces:

43 minutes ago, Scott42 said:

No one has mentioned Pentax XW's so I will....30mm and 40mm.  Currently only available on the used market.  I did a grand face-off contest between the TV offerings and these two - 41mm and 35mm Panoptics, 31mm Nagler.  The XW's are a bit lighter which was the first reason to try them.  They weigh about the same as the 35mm Panoptic, which is lighter than the 41mm Pan and 31mm Nagler.

After many comparisons I became a big fan of the XW's.  Under careful examination I got the impression that all 3 TV eyepieces imparted a yellowish tone to the stars, where the Pentax appeared pure white.  Also the XW's do not employ rectilinear distortion, so the stars appear normal when panning around, instead of visibly bending as the FOV moves across the sky.

Because there is no rectilinear distortion, the 40mm doesn't work so great at lower f-ratios typical of big Newts - you see the field curvature at the edges where the Tele Vue keep the stars as points to the edge.   However the 30mm XW has better edge correction and it's worked well for me at f/5.6.  Between the two of them you have a great high-contrast eyepiece that works well on long & short f-ratios.  I've avoided the ES eyepieces because of heavier weight.

Have you tried comparing the 30mm Pentax XW to the 30mm APM UFF?  areyoukiddingme on CN claims the latter is optically better than the former, but he still prefers the former due to the sharper field stop.

It hasn't been made clear enough in the above posts, but a push-to scope will require you to periodically nudge your scope to allow your object to drift across the field of view of your chosen eyepiece.  At higher powers, this nudging happens more often.  To get more "hang-time", you'll soon be upgrading from simple 50 degree Plossls to super/ultra/hyper wide eyepieces to get longer "hang-time" between nudges.  To get well corrected wide field eyepieces that work well at f/4.7 gets expensive in a hurry.  The goto scope's tracking will allow you to use narrower field of view eyepieces because it will keep the object centered on axis where even simple eyepieces have very good performance.

The goto scope may come with its own host of issues.  Being mass produced, it may require some tweaking to get the tension between the drives and axes perfected.  There are even reports of having to have parts replaced or rebuilt to get them to operate properly.

The collapsible tube has the advantage that you can do prime focus DSLR photography of solar system objects by not extending the struts all the way, and the goto tracking will keep the object centered for short exposures that can be derotated and stacked later.

To add tracking to a push-to scope later, an equatorial platform can be added underneath it and the push-to system put into a tracking mode.  The goto system is a more integrated solution.

If you're curious about the 20mm eyepiece's internals, a contributor on CN did a tear-down, clean-up, and rebuild recently.  It's actually a rather complex little beast.

18 hours ago, Piero said:

Yeah, I would get them from eBay as John Derby suggested. 

A couple of years ago I bought a 1.25" to 0.96" adapter on eBay. It came from China in 2 weeks and cost me about 3 pounds including shipping cost... That was a bargain!

Soap-Box-Mode-On: Remember, because China is considered a developing economy, the Universal Postal Union affords it much lower shipping rates than those afforded to developed nations allowing it to ship items cheaper across the globe than the developed nations' businesses would have to charge to ship it locally.  This forces the developed countries' postal systems to absorb the difference in cost.  It is for this reason the US is threatening to pull out of the treaty establishing the UPU unless things change vis-a-vis China. Soap-Box-Mode-Off

You could also try to locate a UK supplier of vinyl caps who will sell small volumes.

On 26/07/2019 at 12:49, Don Pensack said:

Bear in mind these are the same as the Meades, and lab tests show they are not really 100° fields, more like 88-90°

Look for test reports on the Meades to find reviews.

There are other 100-110° eyepieces marketed by many companies (APM, Lunt, TS, StellarVue, William Optics, SkyWatcher, et.al.) that are made by KUO and are legitimately 100-110°.

I thought that too until I noticed they all have 6 elements in 4 groups compared to the Meade MWAs which have 7, 8, or 9 elements in 5 or 4 groups.  However, I found the same eyepieces available from Kokusai-Kohki as Magellans, and they claim they have the same lens organization as the Meade MWAs.  Does TS have the specs wrong on their website?

I have the 13mm, 17mm, and 22mm AT AF70 versions.  The 22mm is stupendously good.  The 17mm starts to show lateral chromatic aberration, but has a flat field mostly free of astigmatism.  The 13mm has about double the chromatism of the 17mm, but is still mostly flat and astigmatism free.  $70 is a decent price for the 13mm, just be aware that you'll see lots of pretty rainbows starting around 70% center to edge on bright objects.

I actually like the 12mm Meade HD-60 better at this focal length.  Eye relief is about the same, it lacks edge chromatism, has a bit more field curvature that can be focused out, and has some unobtrusive edge astigmatism.  The apparent field of view is narrower, but more usable.

If it's a long barlow, you may not be able to rack the focuser in far enough to reach focus.  If it's a short barlow and you're able to reach focus, it may introduce aberrations of its own unless it's a high quality barlow.  I tend to prefer individual eyepieces in refractors (I have the AT72ED).  Newts are more forgiving of long barlows because it's a long way from the focuser to the secondary, so they can be inserted all the way into the focuser, unlike the situation with a refractor and diagonal.  If you used the refractor straight through without the diagonal, then the long barlow would not be an issue.  I keep coming back to long barlows because the older, affordable, Japanese made long barlows of the 90s tend to give better views than today's Chinese made short barlows for the same money (around $50 to $70 used vs. new).

1 hour ago, John said:

I've not used a Baader Scopos but your feedback reminded me that I had read in the past somewhere that the 35mm is the best of the 2 focal lengths in that range.

Agreed.  With the introduction of the 30mm APM UFF, there's no reason to hunt down a 30mm Baader Scopos Extreme.  I may still pick up a 35mm Panoptic someday if I come across one with the flush mounted eye lens for a good price.