Louis D

You need to decide up front if you are going to store your eyepieces vertically or horizontally, as that determines how deep of a case you'll need.

Check you local big box stores, discount warehouses, and discount tool stores to see what they might have locally.

Pistol cases are also handy, but might be more difficult to find outside the US. 😉

I just ordered another 20mm Svbony 68° for $20 to pair up with the one I already have in my binoviewer.  I'm curious if they will work better than the 19mm Konig pair I have that appear to be from binoculars.  If Svbony stopped them down to 50° as with a Plossl, they'd be really good to the edge.  Compare the generic reversed Kellner below which has a measured 50° AFOV with the same inner 50° AFOV of the Svbony directly below it.  It's pretty sharp at f/6 over that inner 50°.  That, and eye relief would be fantastic for eyeglass wearers compared to a 20mm Plossl.  I have no trouble seeing the inner 60° of the Svbony with eyeglasses when just touching the folded down eye cup to my eyeglasses.  I can hover and still see the inner 50° with ease.

I'll definitely look into getting some anti-seize compound.  I didn't even know it existed.  Thread lock, yes.  Anti-seize, no.  My step rings are always getting locked on each other when attaching auxiliary lenses to camera lenses, and this could be just the thing to make disassembling them when done easier.

29 minutes ago, Tiny Clanger said:

Some Moon filters have a green tinge which I find rather unpleasant , if I was buying again, I'd go for a suitable ND filter which shouldn't introduce any unnatural colour, or the pair of polarisers option (al long as you are using a mirror diagonal, not a prism, someone had mystery problems with a pair of polarisers on here quite recently, turned out they were using a prism).

Yes, reflections off of glass are polarized.  This can be used to the viewer's advantage when using a Herschel wedge for solar viewing.  A single polarizer on the end of the eyepiece can provide a good amount of variable dimming just by rotating the eyepiece.  With my wedge, I have a variable polarizer that I set to fairly dim for unpolarized light and then rotate the eyepiece with the filter attached to adjust the dimming even further.

1 hour ago, PeterC65 said:

@Louis D suggestion of an #80A filter for Jupiter sound like they're worth a try.

You might also want to try an 82A as well for higher powers when the image gets dimmer.  It has 73% transmission versus 29% for the 80A.  The 82A won't significantly knock down brightness, though.

2 hours ago, PeterC65 said:

He said that bright objects like Jupiter can cause glare which prevents you from seeing details with the naked eye. He can wind down the brightness on his camera to compensate for this. It made me wonder whether a filter that reduced brightness a little might be useful for observing the larger planets (and the Moon)? Maybe the Skyglow filter will help.

I would try an 80a filter to knock down the brightness a bit and bring out red features better.  It generally makes the GRS pop if in view.

Once I switched to binoviewing planets and the full moon, this whole issue went away because both eyes are seeing the same intensity.  It's also way more comfortable for extended viewing to pick out find details.  Filters don't really help with BVing in my experience.

Yep, field curvature.  Put the flattener back in and adjust the spacing if needed to get the best star pinpoints in the corners once focused for the center.

That new OIII doesn't look good.  What is meant by Baader when they say "improvement"?  Did they ever define what that means in a quantifiable way?

Did we ever figure out if these are Chinese made or not?

3 hours ago, PeterC65 said:

I’ve not yet been able to upgrade the diagonal (to a Baader 32mm prism), or fit the Baader Skyglow Filter, as the MAK to SCT adapter didn’t fit! FLO have recently changed their supplier for this part and the new part has the wrong inner thread size. They are sorting it out but it will take another few weeks. And there’s me, thinking that the frustration with astronomy would be waiting for a clear night!

😱

3 hours ago, PeterC65 said:

But there seems no value in doing even this unless I can see objects that would merit a wider FoV.

Rich winter star fields like those found in Orion and Perseus as well as the Pleiades benefit from a wider FoV.  There also some along the summer Milky Way to be enjoyed, but they don't pop as well for me because of our continual summer haze due to humidity, forest fire smoke, and Saharan dust.  That, and the lack of regular, strong fronts to clear the air.  Our summer air stagnates for weeks at a time due to a stationary high pressure dome right over Texas.

1 hour ago, Deadlake said:

I'm short sighted, no eyeglasses required. Presume the Panoptic would be the pick? 

A lot of it will depend on the shape of your face.  I have deep set eyes with a prominent nose bridge such that I can't fit it between Morpheus width eyepieces (55mm).  The 19mm Panoptic would probably not be an issue for me due to its narrower width (43mm) and conical top.

Yes, all the LV, NLV, and SLV eyepieces below 9mm were and still are 45°.

The original LV line also had 7mm and 18mm 1.25" versions that were dropped.  The 30mm LV 2" was dropped in favor of the 30mm NLVW.  The 50mm LV 2" was dropped without a replacement.  The 40mm 1.25" carried on into the NLV line but was dropped with the SLV line.  The 8-24mm zoom was also dropped with the NLV line.

The 9mm LV was my first eyepiece.  It is still quite good, right up there with the Pentax XL/XW and Delos lines, just narrower (48° measured via both projection and photography).  I just don't get on with its stiff, roll down eye cup.  However, it does allow for a full 18mm of measured, usable eye relief that the NLV and SLV eye cups do not.  Today, though, I tend to prefer the 9mm Morpheus at this focal due to its much wider field (78°/79° measured via projection/photography), slightly longer usable eye relief (20mm), and just as sharp images for most of my viewing.  I'll have to have a shootout between the 9mm Morpheus and LV someday just to confirm.

However, all that being said, I find I see more detail on the planets and the moon using binoviewers with adapted microscope eyepieces than monoviewing with any eyepiece.  It reduces the appearance of floaters and keeps my eyes from being overwhelmed by the brightness differential between my two eyes in monovision at the opposition of Mars, Jupiter, and Luna.  Brightness is not such a big deal on Saturn, Neptune, or Uranus because they are considerably dimmer.

The 19mm Panoptic was designed with BVing in mind.  They are compact and light weight.  However, eye relief is too short for eyeglass wearers.

I found the BHZ too tight on eye relief for an astigmatic eyeglass user like me.  I use a Celestron Regal zoom eyepiece with the adjustable eye cup screwed all the way off to maximize eye relief.  They also work well as a pair in a binoviewer.  Since I picked them up for $60 apiece, I've been quite happy with them.  Since the top doesn't rotate, batwing eye cups are also possible with BVs.

The 20mm APM XWA would probably work well for you except that it isn't in stock anywhere.

The 22mm NT4 won't correct for coma.  Al is simply stating it is well corrected in an f/5 scope for things such as astigmatism and chromatic aberrations near the edge.  The APM XWA won't be too much different.

The 24mm APM UFF and 24mm Panoptic wouldn't come close to your goal of (nearly) maximizing true field of view.

The 13mm would probably get used the most since it provides a nice (high) mid-power.

Instead of a Paracorr II, you could start with a GSO coma corrector (Revelation, Omegon, TPO, Astro Tech, Apertura, etc.) and a 25mm M48 spacer ring between the optical element and the eyepiece holder if your budget is tight.  It will correct 90%+ of the coma in that configuration for eyepieces that focus within 5mm of their shoulder.

Is eye relief an issue for you since you chose long eye relief eyepieces at 24mm and presumably 17.5mm?

The 2.6 GPC (or simply a high quality Barlow element in my experience) would work great with the 24mm and 17.5mm eyepieces to yield higher powers.

I would look into a pair of zoom eyepieces because swapping eyepiece pairs is a royal pain, especially at high powers; although I suspect you're using a tracking mount.

23 hours ago, Second Time Around said:

The Baader is the best medium power zoom I can find (at the moment) that accepts a Dioptrx.

How do you deal with the fact that the BHZ top rotates as it is zoomed?  Doesn't this require reorienting the Dioptrx after each zoom?  The rotating top of the BHZ is what keeps it from being used in binoviewers with batwing eyeguards.

9 hours ago, 0rcrest said:

just reading this ,about to choose between the 12/15/18 bst  starguider  i already have the 25mm and 3.2 on f5 130p struggling with the 3.2 but moon and saturn good though on a good night 25mm lovely

The 12mm is the best corrected to the edge of those three.  I would add the 5mm and/or 8mm next.

1 minute ago, KP82 said:

I had the problem with ghosting on bright targets using the 5mm (very prominent when looking at Mars or Jupiter), not sure if it was just my particular sample.

I haven't looked for ghosting in my Paradigm/BST samples.  I suppose I'll have to explicitly look for it sometime.

1 hour ago, Gonariu said:

I think a travel telescope must have these characteristics:
3) that it can be mounted on a photographic tripod.

Why the  photographic tripod requirement?  A compact travel Dobsonian is it's own base:

On 04/09/2021 at 13:01, Ricochet said:

My 18mm does. It's right at the top of the barrel, but it is there.

21 hours ago, Don Pensack said:

The 18mm has one fewer lens than the 15mm.  The 15mm is 6 elements, the 18mm is 5.

Either the negative lens is gone, and the correction is applied in the upper positive design, or a very weak negative lens is place close to the upper section.

I unscrewed the chrome barrel from my 18mm Paradigm/BST, and it does indeed have at least one lens at the very top of it.  I didn't try to ascertain whether it was a single lens or a doublet.

Have you tried it during the daytime on a distant target to see if it focuses under those conditions?

I'm thinking a thin layer of silicone lube wiped on with a cloth would work well without ever drying out.

Since your achros are around f/10, you might give the Svbony 68° UWA a try for under $30 a try.  They're pretty good in longer focal length scopes.  They are sold under other names as well, sometimes advertising 66° FOV.

On CN, Markus reports UO has started production and first shipment to his home is expected in October.

Just checked mine, and yes it does have a lens in the chrome barrel.  It's up there a ways compared to the shorter focal lengths, but it's definitely with the barrel.

Thanks for the heads up about the 18mm.  I knew the 25mm didn't have a Smyth lens in the barrel, but never realized that the 18mm didn't either.  In fact, both have their field stop below the field lens, so they're actually positive-only designs.

I compared them to the Meade HD-60 18mm and 25mm which both appear to have lenses in the barrel.  That's probably why they have better correction at the edge than the BST Starguiders/AT Paradigms.

6 hours ago, Orange Smartie said:

Quick update - following recommendations from @Louis D and @Spile, I got hold of a water butt stand from Wickes.

Glad it worked well for you.  Enjoy the summer/early fall skies, there's lots to see up there right now.

I just find it amusing that Brits call rain barrels water butts.  Pork butt, sure; but water butt?  Apparently, the term "butt load", which Americans still use, derives from this older meaning of the word, but we have long since forgotten the origin of the term.