Louis D

29 minutes ago, Stu1smartcookie said:

Hey ... lol ... i've got a new flat in Russia to design and furnish !!!! if i spend spend spend on expensive EP's i will be living in the box my next scope is delivered in ! 🤣

My son just graduated college (with a minor in Russian no less) and furnished his new apartment in San Antonio entirely from Craigslist and Facebook Marketplace for under $500.  It's all vintage to antique stuff, so very well built.  He just borrowed my Chevy Astro van for 2 months to haul everything.  Hopefully, Russia has similar places for classifieds.  With the money saved, you might be able to afford some nicer eyepieces.

3 hours ago, Cosmic Geoff said:

Personally I see no need to use these laser pointers on the night sky

Just wait until your neck and back are so stiff with injuries, age, and arthritis that you can't bend around properly to use a unit power finder (RDF/QuikFinder/Telrad/Sighting along tube/etc.).  A green laser sight has been a game changer for me.

1 hour ago, Astro_Nic said:

Will the Delos  cause more drift problems and constant adjustments at that magnification in a dob?  Thanks

If you mean less dwell time on target when manually tracking with a Dob, then yes.  The narrower the true field of view at a particular magnification, the more often you have to nudge the scope.

Generally, true field of view aligns with apparent field of view, but there is some variation due to distortion issues.  Doubling apparent field of view doesn't generally equate to doubling true field of view due to increasing edge distortion.

You might look for something in the 5mm to 7mm range to get above 200x on nights of good seeing.  Since you don't seem to need long eye relief, that opens up a lot of options for you.  Within the APM XWA line, there are a couple of options in this range (5mm and 7mm).

At the long end, you probably won't find yourself using a widest field eyepiece nearly as much as a mid-power to high-power eyepiece.  I mostly use my widest fields as finder eyepieces to help center objects for higher power observations.  I'll admit, though, that I do sometimes enjoy sweeping rich star fields at low power just to see what I'm missing at higher powers.  However, the 1600mm focal length of your scope doesn't lend itself well to this usage.  As such, I wouldn't spend big bucks at those focal lengths.  A modestly corrected, widest field eyepiece will be good enough for quickly centering bright objects like planets and the moon before swapping it out for a better corrected, higher power eyepiece.

It's a well executed UWA eyepiece using old school design techniques that don't do well in fast scopes.  Apparently, the polish and coatings on the lenses are phenomenal, so the central region is exquisite with the outer region framing it for context in your peripheral vision.  If you always observe on axis using a tracking mount, you might never be bothered by the outer region aberrations.

I don't know about SGL discussions (I can't find a single user report here), but it was extensively discussed on CN 4.5 years ago:

https://www.cloudynights.com/topic/562496-masuyama-32mm-85-deg/

https://www.cloudynights.com/topic/585719-31mm-nagler-type-5-vs-32mm-masuyama-85-degree-at-f7/

https://www.cloudynights.com/topic/568762-32-masuyama-vs-30-xw/

https://www.cloudynights.com/topic/555445-initial-impression-masuyama-32-mm-85-degrees-under-the-sky/

1. Make sure the batteries are inserted the correct direction.
2. Try another battery, especially one known to be working in another device.
3. Do not use rechargeable batteries.  They only put out 1.2V.  You need 1.5V for these.
4. Screw and unscrew the battery holder section while holding down the button.  Sometimes, slightly loose works best.
5. Try scraping the contacts with a jewelers screwdriver.  Tarnish may have built up in storage or transport.
6. Shim the battery compartment with a card stock sleeve to better center the battery.  The positive contact on these can be troublesome.

3 hours ago, tomato said:

A much bigger problem is getting the clear nights to use it, alas no device available that works to fix that one.

Zarkov Cloud Gun to the rescue. 😉

Entry level binoviewers with ~22mm clear aperture have around a 100mm to 110mm optical path length.  Simply measure how far out your focuser is relative to its most retracted position with an eyepiece you would use in a BV focused at infinity in a 1.25" diagonal you already have.  Subtract that distance from 110mm if it is smaller.  The result is how much distance you need to remove from your current optical path to reach focus natively with the BV.  If you are already racked out more than 110mm at infinity, you should be in good shape to use a BV natively.  My APO refractor has a removable tube section ahead of the focuser to aid in reaching native focus with BVs.  It's one of the reasons I chose it over other options.

36 minutes ago, Prathab said:

But we are blessed with many cloudy days to learn.

Now that is what I call a positive attitude. 😁

27 minutes ago, paulastro said:

Well Louis, certainly no problems with dripping sweat everywhere in West Yorkshire while solar observing - with or without the dark cloth I have over my head 😊.

I should think not looking at this comparison chart of average high temperatures for Leeds versus San Antonio, TX:

And our mid-October to late March does indeed roughly correspond to the peak of your summer temps.

Decloaking my mushroom top ES-82 30mm dropped the weight from 1369g to 973g, a 29% weight savings.  The process is not as reversible for it since the glue holding the stiff rubber eye cup wouldn't let go causing some damage while it was being pried up to access the helical screw.  I still have to tip my head sideways to get my eye up to the eye lens.

Below is a group shot of it on the far right with other ~30mm eyepieces.  I don't think I have any before pictures of it.

I need to come up with a way to block sunlight from directly hitting my body during the summer here in Texas while solar observing near noon.  Within minutes with no hood, I'm dripping sweat on everything, so I retreat to the AC of the house to cool down.  A box fan blowing across me helps to delay this a bit.  Wearing a broad brimmed, well ventilated hiking hat helps block sunlight from the eyepiece while preventing excessive heat build-up around my head and sunburn to my exposed skin.  As a result of all this, I tend to solar observe mostly from mid-October to late March.  That reflective solar blanket might prove useful as long as I can get decent ventilation under it.

I'm guessing it's quite a bit cooler in Europe during the summer based on folks using hoods while solar observing.  I'd love to try early morning observing when it's much cooler, but I've got solid trees to the east of my observing site.  To the west are houses with heat waves radiating off their roofs, so solar noon it has to be.

According to Company Seven:

William Optics Corp. was founded in 1996 as "Optical technology Limited" by brothers William and David Yang for the purpose of making astronomical telescopes for use by the more demanding amateur astronomer and birder. The company is based in Tapei, Taiwan, with optical production of their telescopes in Taiwan. William Optics has established offices and distributors overseas including in the USA. Unlike many other companies based in China or Taiwan at the time the Yangs set out to develop telescopes that are more refined in terms of performance and durable, with features that appeal to the more demanding amateur. The William Optics company subcontracts their designs for production by other companies, and also resells products that are sometimes marketed by other companies too.

31 minutes ago, Andrew_B said:

I think you'd struggle to get the best out of a big scope of any kind here in the UK compared to many places in the US.

I'm sure that's what's going on.  During the dead of summer here while we have a stationary high pressure dome parked over us for months (can you say drought?), the seeing is rock steady and temperatures drop slowly at night.  As such, it's quite easy to bump up the power on large Dobs to have the same exit pupil as that of a smaller frac.  Under these conditions, it is so much easier to make out fine planetary details at the larger image scale and higher theoretical resolution of the big Dobs than in nearby fracs.  UK seeing conditions are probably the dominant reason for the lack of popularity of big Dobs there.  They would probably just show a boiling mess of turbulent atmosphere.

There are several newer computerized EEVA telescopes that are supposed to make the process foolproof:

eVscope eQuinox

Vaonis Stellina
 

😉

I look at it this way.  If you've got $10,000 to spend toward getting the best planetary views, a decent sized Dob with a Zambuto mirror will blow the doors off a similarly priced APO and quality mount on most nights here in Texas.  Perhaps things are different in the UK, but I've always been underwhelmed by the planetary views through high end APOs when compared to the views through high end Dobs of similar money at star parties here.  We are generally pretty far south of the jet stream, though.

5 hours ago, vagk said:

What about Explore Scientific 20mm 100° ?

Has it so much difference from Ethos and APM ?

21mm Ethos - $853.00

20mm ES-100 - $799.99

20mm APM XWA- $329

There's no reason to not spend the extra $53 and buy the Ethos over the ES-100.  However, the APM is less than half the cost of either of the other two.

The APM is lighter than either of the other two (678g vs 968g for the ES-100 and 1021g for the Ethos).  Most reviews on CN comparing the three put the Ethos well out front in correction and contrast in fast scopes with the APM not far behind, suffering only in the outer 10% to 15% of the field and having some slight stray light control issues.  The ES rates similarly to slightly behind the APM.  The 20mm APM is generally regarded as the weakest of the XWA line of eyepieces, and yet gives up nothing to the ES.  There is literally nothing to recommend the ES over the APM unless it were to be availability for immediate purchase.

On 13/10/2021 at 09:02, johninderby said:

On closer inspection of this photo, I realized that you'd need an M48 spacer ring (empty filter ring) to keep the field lens of some 2" eyepieces from crashing into that raised metal ring inside the M48 thread if you tried to screw the eyepiece directly to it.  Legitimately, I could see attaching an 12mm ES-92 to it with minimal vignetting, although I'd probably go the route of the 2" to T2 thread visual back for quicker eyepiece swaps.  Of course, the eyepiece would weigh more than the entire scope (1011g for the 12mm ES-92 vs. 792 for the Mak).

2 hours ago, johninderby said:

This is the T2 eyepiece holder. 365astronomy used to sell it but can’t find it on their site. Any T2 to 1.25” adaptor with a 35mm length would do. Perhaps a Baader one?

Found this available in the US:

Blue Fireball Eyepiece Holder (1.25") with T / T2 Female Thread (T2 Visual Back) # E-10

And if you want a 2" to T2 visual back:

Blue Fireball Eyepiece Holder (2") with T / T2 Female Thread (T2 Visual Back) # E-09

16 hours ago, johninderby said:

A standard 1.25” to 2” adaptor will also screw right on but is a bit bulky.

That means a 2" eyepiece with filter threads could be screwed onto the back as well.  You should try a max field eyepiece with a ~46mm field stop diameter on it for giggles to see how much it vignettes. 😁

25 minutes ago, johninderby said:

Ah a good old root beer. Hard to get hold of in the UK and expensive when you can find it. One soft drink that never caught on here.

Even better as a root beer float with a couple of scoops of vanilla ice cream.  Yummy!

1 hour ago, nfotis said:

Intriguing.

So, what's the smallest Mak which can accept directly 1.25" eyepieces?

N.F.

There is the older PICO-6 60mm Maksutov, of which I have a used copy, that can accept 1.25" accessories natively.  However, the optics have severe spherical aberrations visible at anything above the lowest power possible, so it's more of a conversation piece for me.

2 hours ago, Ian McCallum said:

You should see the fun and game getting a couch through the front door!🙄

Now that you mention it, a few years ago I had bought a loveseat for my son's room in a fraternity house built in the 50s.  It turns out, the doorway was too narrow to fit it through no matter how much the delivery folks tried, so it had to go back to the warehouse for a refund.  My son was pretty bummed out.

1 hour ago, johninderby said:

The gov in the UK is finally getting around to legislating disability access for landloards ( The National Disability Strategy ). Minimum legal front door clear opening in the UK is 775mm but older houses may not be up to standard.

And I'm sure the UK has a LOT more older houses and multifamily dwellings (apartment buildings in US English) than the US to be grandfathered. 😉

However, if you do a major remodel (gutting interior walls, moving entrance doors, etc.), you may have to meet ADA guidelines during the permitting process of the redesign.

In the US under ADA guidelines, businesses have to make accommodations unless they can get protected historical status (like old basement pubs).

There was a lot of grumbling when the ADA was signed into law 31 years ago, but now it's just accepted as the current normal.  Things like office building ramps have turned out to be a boon for delivery folks with heavy pallets, so it's had unforeseen benefits.  Ample handicap accessible parking has been welcomed by the aging Boomer generation as well.