Louis D

I have a late 90s Lumicon OIII that made the Veil nebula visible in exquisite detail under my Bortle 5/6 skies in my 15" Dob.  Without it, I couldn't make out any of it.  It also works well with my 8", but the bigger the better with OIII filters.

1 hour ago, Paz said:

I notice the 17.5 Morpheus is  about 1/3rd lighter than the 17.3  Delos which adds to quite a weight saving when there's two of them.

Probably due to the use of engineered plastic case materials in the Morpheus and brass or another dense metal in the Delos.  Delrin and aluminum bodied eyepieces are both noticeably lighter than their brass counterparts.  One downside to them is that the threads can be cross-threaded more easily, so filters and disassembly/reassembly can be problematic.

Optically and mechanically, Sharpstar Optics have been doing a good job of producing consistently excellent, premium refractors at affordable prices.  They're usually sold under various house brands around the world.  If you look at their focusers, you can usually distinguish their products from other Chinese optics houses.  I have a TS-Optics 90 mm f/6.6 FPL53 Triplet APO that has excellent optical correction and refined mechanicals.  It's pretty clearly an older Sharpstar.

Have you read this webpage?

Semi-apo and apo lens objective examples

Here's an instructive set of diagrams of various doublets and triplets:

The glass types are explained in the table above it on that webpage.

My takeaway from this diagram is that there is no one best solution.  Refractors will always be a compromise when it comes to bringing all wavelengths to a common focus across the entire field.

On 07/01/2021 at 01:32, Merlin66 said:

I’m surprised you found a concern with IR transmission.

Yes, the longer I observe, the more it feels like my eye is being cooked despite there being no pinholes nor excessive brightness.  There is a general feeling of fatigue and soreness in my observing eye after a time without the IR blocking filter.  I noticed that the Lacerta Herschel Wedge recommends using an IR block filter, so I don't think I'm losing my mind.  They claim mainly for photography, but that means it's getting through if a camera sensor can pick it up:

IR/UV Blocking filter and Baader Solar Continuum Filter is also recommended, especially when used for photography.

If a Herschel wedge can pass IR, I have little doubt Baader Solar Film can pass it as well.

Remember, too, I'm in Texas where the sun's intensity can sunburn a fair skinned person in 10 to 20 minutes during summer noon.  I always wear a wide brimmed hiking hat when I'm outside in the summer for more than 10 minutes at a time, such as at fairs or when solar observing, to protect my bald spot, ears, nose, and neck:

Tried to google Lacerta Wedge in the US, I got the following hit for a Lacerta Group Sandwich Container 2-Wedge:

I thought it was a prank at first, but no, it's real.  It's probably most useful for staving off hunger while solar observing. 😁

Still trying to find a US retailer for the Lacerta Herschel Wedge.

44 minutes ago, bsshog40 said:

My only other question would be if all T-rings are M42 threaded?

Yes, all T-rings are M42 (42mm x 0.75mm thread pitch).  They are not to be confused with the M42 lens mount (universal screw mount) which is 42mm x 1mm thread pitch.

On 01/01/2021 at 02:49, Ande said:

Noticed another trend amongst certain retailers too. The habit of showing “low stocks, please call” or words to that effect. And then when you do call, they immediately tell you they don’t have the item, they don’t even need to check as they know full well they’ve hardly got anything. But then they instantly proceed to try and prise your details out of you so that they can procure an order for when stock does eventually arrive. I don’t appreciate people trying to trick then trap me, and will actively seek to avoid those places in the future.

Or reverse this, and put yourself on the waiting list for 15 different shops and see who comes in first with new stock.  Just don't provide any payment details such as a CC number to any of them.  You shouldn't have to put down money to join a waiting list, even for custom made items like AP scopes.  You might wait 10+ years on an AP list, but if they decide to build a scope again, they'll work their way down the wait list and ask each person if they're still interested enough to put down a deposit at that time.

Comparing my 8" Dob to my 127 Mak, the former is easily the more versatile scope.  It provides wider views, more detailed planetary images, and brighter DSO images.  It also handles the weight of 2+ pound eyepieces much more easily.  The Mak is much more compact and handles binoviewers more easily.  I would start with the Dob and get the 127 later if you feel a need to take a scope camping or on vacation (holiday).

Perhaps it was a custom made or limited availability adapter?   In 20+ years of astro shopping, I can't recall ever seeing one being advertised or reviewed.

It's certainly a very nice idea for eyepieces that don't have hidden M43 (or similar) or T-threads to allow for camera attachment.  It negates the need for an eyepiece clamp which are pretty dodgy anyway.

21 hours ago, a5tarman said:

In the end I settled on the 24mm ES82° rather than getting the 17.5mm Morpheus.

Be prepared for tight eye relief.  The combination of a small eye lens (23mm) for an 82 degree field coupled with a deep recession will make it tough to use even without eyeglasses.  Ernest in Russia measured the usable eye relief to be between 5 and 10mm while the design ER was 14 to 19mm.  I think the uncertainty is due to CAEP (chromatic aberration of the exit pupil) where the red and blue ends of the spectrum form images at differing eye reliefs.  I've noticed this with my 30mm ES-82.  The exit pupil is a vague smallest circle that is red at one distance, white in the middle, and blue at the other end distance-wise from the eye lens.  This also manifests itself as the ring of fire with an orange-red ring around the periphery of the view.

On 02/01/2021 at 17:22, John said:

Goodness knows what size and cost of equatorial mount that I would need to have to hold my 12 inch F/5.3 as solidly as my compact and lightweight 18mm ply dobsonian mount does

Probably something like an AP1200 or AP1600 mount or a Parallax HD300C would do nicely. 😉

35 minutes ago, bsshog40 said:

It's for  1.25 eyepieces but the only lens that fits into it is my 8mm. The rest are all a little too fat to go into the body of the adapter.

I guess eyepieces have gotten chunkier over the years just like their owners. 😉

I made Baader Solar Film filters for two scopes about 20 years ago when it was first introduced.  Both are still going strong.  I followed the instructions and used sheets of craft foam board, double sided tape, strips of poster board, and clear packing tape.  It wasn't difficult at all.

Larger scopes do seem to make for a brighter solar image, but a moon filter or colored filters can be used to cut down the brightness.  I've taken to adding an IR-cut filter intended for imaging because it seems like there is an excess of IR energy causing discomfort to my observing eye.

I looked at the C90, but decided to pick up a second hand 127 Mak for about the same money as a C90 new.  It's actually about 118mm of clear aperture, so only a bit bigger than the C90 in the big scheme of things in both aperture and physical dimensions.

I've found it to be good for solar system views and planetary nebula as well as the Orion nebula and Trapezium.  Pretty much, it excels at small, high contrast objects.  It does best paired with a short focal length ED refractor or 50mm or larger finder scope given the Mak's super narrow field of view.

After attending a star party 24 years ago and looking through most telescope types, I determined that the Dobsonian Newtonian was the best starter scope for me.  As I recall, I was most unimpressed with SCT views as being soft in comparison to those of Newts.  APO refractors simply lacked aperture to compete with the big Dobs.  I don't think there were any Maks on the field.

It's funny that everything you describe about SCTs from your experience correlates very well with that single night of "comparison shopping" I did so long ago.

I am thinking about getting a 6" or 8" SCT just see if things have improved any over the last 24 years.  I was super impressed with the views of Jupiter through an 8" EdgeHD a couple of years back at a star party, so it got me to thinking they might be worth another look.

Have you turned off live view and taken an image to verify a difference in behavior?

I know that in live view on my Cannon T3i, I can't trigger an on-camera flash for some reason.  Once I turn off live view, it works fine.

6 hours ago, michael.h.f.wilkinson said:

I doubt I would have been able to put an 8" Dob tube in my old Peugeot 106, along with all the camping gear when I went to France to see the eclipse in 1999. The OTA is way more compact and lighter, the mount head is quite modest in size when you stow it, and the tripod is a very light manageable unit as well. The Dobson OTA is quite a beast in comparison. The base is also quite bulky.

That's why I set up my grown daughter with a 127 Mak on a DSV-1 mount and Manfrotto tripod for her camping trips at dark sky sites.  With the camping gear, SO, and dog, there isn't a whole lot of room left in the back of her CUV for an 8" Dob.

To improve on the 8" commercial Dob's view while keeping the weight down, you could go with a custom 10" or 12" Dob such as the Sumerian Alkaid line.  You wouldn't have goto or AP possibilities, though.

1 hour ago, a5tarman said:

Would a second hand 24mm panoptic be worth it over an ES82deg 24mm?

If you like the long eye relief of the Morpheus line, I'd recommend the 24mm APM UFF.  At 30mm, I'd recommend the 30mm APM UFF.  If you are budget constrained, the 22mm Omegon Redline SW (or other brandings) is a slightly lower cost 2" option that also performs very well and has long eye relief.

If you can store your filter bare and vertically, they're fairly easy to grab without worrying about touching the optical surfaces.  As far as attaching them, I generally screw the eyepiece onto the filter so my grip on the filter never changes to minimize the chance of putting a fingerprint on the glass.  I align them by grasping past the filter with fingers so the tips of my fingers guide the eyepiece barrel into position above the filter threads.  I also work slowly and methodically to avoid cross threading anything.

You could try to locate a case similar to the one below for eyepiece kits and dedicate it entirely to filter cases stored on edge:

2 hours ago, Second Time Around said:

We're having a new lawn laid later in the year. In the meantime I've had a single slab laid to put my scopes on.

I had thought about additional slabs to walk on, but was concerned they'd heat up during the day and affect the seeing at night as they cool down.

Any thoughts?

Most landscapers around here use cut rock or concrete edgers to demarcate the path and then pave the path with gravel and/or pavers of some sort rather than pour concrete.

I would think these would have less heat build-up than poured concrete and look much nicer.

Since most of my filters were purchased used, only a few came with cases.  For instance, I have some vintage Optica b/c filters that were NOS, but were simply packaged in plastic baggies folded over and stapled shut with a cardboard hanger tag for shop display.

Some are kept tucked into a pick-n-pluck foam slot in my Doskocil case along the outer edge.  Be sure you're using a high grade of foam that neither crumbles nor becomes gooey over the years.  After 20+ years, no issues so far.

The rest are kept in a Tamrac 5329 filter wallet.  Unfortunately, it has been discontinued.  Two 1.25" filters or one 2" filter will fit in each pocket.