New Telescope

[Alan64]

Practically all of my life, since I was about nine years of age, I've owned and enjoyed telescopes designed in the 1600s.  All I might add to that is: when you've got a good thing going, and for over 400 years and counting, then quit whilst you're ahead.

This latest acquisition is one for which I've been longing, and for quite some time.  On more than one occasion I've stated...

"I plan on getting one of those myself in future."

The future has arrived at last...

Double-boxed, and expected...

<creeeak>...

What in the name of James Gregory could it...oops.

[MarsG76]

Ah the new scope feel.... so what is it?? Newt, SCT?? 

 

[johninderby]

AZ-GTI mount or something similar? 🤔

And maybe an OTA?

Edited May 29, 2019 by johninderby

[heliumstar]

Come on! Don't leave us hanging

[Peter Drew]

A nice period Gregorian reflector?   😀

[JamesF]

31 minutes ago, Peter Drew said:

A nice period Gregorian reflector?   😀

With a speculum metal mirror?

James

[Alan64]

The telescope came with accessories, and a mount to boot.  But the mount, an alt-azimuth, will need renovating straight away.  I have some material on order for it, although it will not be described nor illustrated until it's righted. 

Out of the box, the threaded end of the altitude handle was crooked...

I "warmed" it up with a mini-torch and straightened it as best I could.  I was fearful that it might snap off altogether.  Perhaps the torch tempered the soft imported steel, I can only hope.

One eyepiece was provided: yet another kit-25mm, and a Plossl.  I've never used my 25mm eyepieces, a total of four now from kits, and in preferring a 20mm instead...

The red-dot finder...

The battery's good, but the chassis shakes and wiggles like a bowl of gelatin.  Elsewhere, someone who has one just like it suggested adding springs to the cross-screws.  I do have a box of assorted springs, but do I really want to go to the trouble?  I have other means.

What is this?  I've never gotten an accessory quite like this before...

Why, it's a dumbphone holder; bizarre to say the least.

An empty box...

Not unexpected; although as I fished it out I did have high hopes that it contained something lovely.

A mirrored star-diagonal...

I've never had one of those before, but I now have one with which to experiment and play.

I suppose we now know that it's not a Newtonian; drat.  But still, what could it be?

[Ricochet]

I'll guess an ES Firstlight Mak, 100 or 127mm. 

[Alan64]

"I've never had one of those before..."

I take that back, as I do have this 2" mirrored-star...

[Alan64]

The big box is almost emptied, save for this last box...

[Rusted]

The black "octopus" is actually a soap dish to go on the vertical shower rail.

I'll go with a Mak, too.  

[Alan64]

[Alan64]

Many times in the past, I have also stated...

"A 127mm Maksutov is the 'sweet spot' among the varying apertures of the design; not too small, not too large, just right rather"...

A Jinghua Optical Co.(JOC) 127mm f/15 Maksutov-Cassegrain...

It is identical to that branded "Bresser", and perhaps the Meade 127mm as well.

[Alan64]

Undoubtedly it has experienced slow sales, which is how I got it for a song; a promotional I suspect: US$299(£236), and from a vendor in New York.  I've been aware of its presence within the marketplace for quite some time, but so little information has been forthcoming.

I came close to deciding upon the Orion-of-California model, a Synta, as are the Celestron and Sky-Watcher models, at f/12, and all three apertures actually at 118-121mm.  I did find this out about the Jinghua: it has a full 127mm of aperture...

  

...and at f/15, a slightly smaller secondary-obstruction.  That, combined with what I thought to be a promotional, made it a no-brainer. 

Edited May 29, 2019 by Alan64

[Ricochet]

Looks good Alan. Let us know how you find it in practice, and the mount that was supplied with it. 

[johninderby]

I like my Bresser version and yes having the full 127mm aperture does help. BTW an Orion finder shoe fits nicely. I’m using a Baader T2 prism on mine.

Edited May 29, 2019 by johninderby

[Alan64]

The collimation appears bang-on fresh out of the box...

I made a dew-shield straight away, in a pinch, and with these sheets of art-paper...

 

As I had said before, the bundled mount, an ES "Twilight Nano", cannot be utilised at present, notwithstanding the fact that it's not ideally supportive.  My only recourse was to place the telescope upon my Astro-Tech Voyager I, a GSO product...

  

I didn't dare take it out of the house without a dew-shield, with the micro flora and fauna whizzing round.

The only thing I could point it at were tree leaves in the distance, lots of them.  So I did, and at 190x...

The live view was sharper of course, as the eye and mind can follow an object more easily when a breeze ensues.

[Alan64]

Despite the 1900mm focal-length of this telescope, I have little to no trouble in quickly bringing the objects that I view regularly to bear within an eyepiece: Polaris, the major planets, and the Moon; even in the absence of a finder.  I simply sight alongside the tube.  Here, under Bortle-4 skies, which might easily become -5 in future, there are a number of globular-clusters that I can readily locate, but not by sighting down the tube.

This is the base for the red-dot finder, and similar to that of a Meade...

At first I thought it was of metal.  

I have a couple of Vixen-type bases, but I'll need longer screws to attach one; and yet another trip to my local hardware, to where I've suggested a cot in the back of the store.

I have this 8x50 straight-through...

That will do for the time being, and another red-dot that I have in addition.  I'll try both and see which performs best for my purposes.

The dovetail-bar is of white-painted metal, and with a steel strip fastened onto one side, as a clamping surface.  That of the Bresser is identical, but painted black...

I'd like to replace it; perhaps tube-rings in addition.  That would add extra weight however.

The plastic dust-cap has two locking tabs...

The meniscus is multi-coated and uniform...

...and very much like that of my Meade 90mm achromat...

The secondary-baffle, and flared, like a vortex,...

That will be altered, or ripped out altogether, albeit ever so gently.  As I understand, the telescope as it sits is optimised for daytime/terrestrial use.  That won't do.  Its presence also increases the size of the obstruction, and that won't do either.

The primary-baffle...

The reverse of the Gregorian "spot", and facing outwards...

I've thought about a matte-black disc.  Schmidts don't seem to have that problem....

https://www.flickr.com/photos/140554065@N05/47962213786/in/dateposted-public/

[johninderby]

On the “baffling” subject have you read this? Some very usefull info.

http://mirrorworkshop.mtbparker.com/cassegrainBaffleStory.html

 

One of the Orion type finder mount fits directly Using the original holes. Be aware that the rear dust cover of the scope that covers the metal back plate is plastic and the finder screws strip easily. I taped the holes to M5 and it seems solid. You could always remove or just parially remove the dust cover enough to put nyloc niuts on the inside for a really solid job.

Like the way the inside of the OTA has micro baffles all the way front to back. So much better that just a painted surface.

Edited May 30, 2019 by johninderby

[Alan64]

First light...no, not when I took that image of the leaves during the day...

The very first celestial object I saw through my new and only Cassegrain was old Jove, and at 190x...

Of course it's blurred.  I used a 2002 Minolta 4MP point-and-shoot, and with a manual mount.  Still, you can see a single moon at upper-left.

All four were seen quite well during the live view, naturally.  When I first had the planet in view, I saw one moon emerging from the side of the planet.  It appeared as a little bright dot, and sharp.  That was nice.  

The image brightened, and now two moons are visible...

The moon closest to the planet there was the one that had emerged earlier.

The whole night I was bothered by cloudlets and haze wafting across the sky.  It's nigh summer.  But the haze did have a beneficial effect.  Jupiter was dimmed slightly in consequence, its lovely colouring revealed, as shown. 

The only detail seen on the planet's surface were the usual equatorial bands; and perhaps, just perhaps, a spot that I think I saw, but cannot say for certain.  This is the eyepiece I used: a 10mm 70°...

...and with these strange, amber-like coatings...

...much mysterious, that one.

[Alan64]

39 minutes ago, johninderby said:

On the “baffling” subject have you read this? Some very usefull info.

http://mirrorworkshop.mtbparker.com/cassegrainBaffleStory.html

 

One of the Orion type finder mount fits directly Using the original holes. Be aware that the rear dust cover of the scope that covers the metal back plate is plastic and the finder screws strip easily. I taped the holes to M5 and it seems solid. You could always remove or just parially remove the dust cover enough to put nyloc niuts on the inside for a really solid job.

Like the way the inside of the OTA has micro baffles all the way front to back. So much better that just a painted surface.

 

Thank you for that most useful link, John.  

Yes, I see...

And here I thought it was of metal.  Why am I not surprised.  Incidentally, the focussing knob was loose upon arrival.  It takes a 1.3mm hex-key, but I'm fresh out of those, so I used one of those tiny flat bits from a mini magnetic screwdriver.

Also, might I integrate a 2" visual-back to this, please?  Would it be worth it, given the diameter of the primary's bore?  

 

[Alan64]

"Like the way the inside of the OTA has micro baffles all the way front to back. So much better that just a painted surface."

Yes, I had seen those online, but not as clearly as this...

And here I have this new box of Protostar...

Alternately, I have to wonder if JOC's factory-black is as black as my rattle-can of chalkboard-black.  That stuff is almost as black as a black hole...

There's got to be something or other within to flock.  I might at least flock from the meniscus almost all the way back to the primary.  The baffled surface would have to be high-glossed, for improved adhesion.  However, I do suspect that in that the telescope will sport a flocked dew-shield 24/7/365, then perhaps said enhancements would be to no avail.

Incidentally, whilst mucking about inside with the camera, it seems that JOC's clean-rooms, if equipped, aren't up to the task.

[johninderby]

Did some testing of a Skymax 127 with a 2” diagonal and found yes it does give a slightly wider fov. A 2” 30mm 70 degree eyepiece gave the widest fov and the vignetting wasn’t really obvious although of course there was some.

However is rhe added weight worth it for the small gain? 🤔

I too have a roll of unused flocking. 😁

The second thing I saw through the scope (after the moon) was Jupiter and remember being impressed by the detail this little scope was showing. I call it my grab’n’go planetary scope. 

[Alan64]

First-light continued with Polaris, the North Star, at 190x...

...most impressive.  Incidentally, I've had my camera, again, since 2002, but it's only now that I've discovered how to adjust the shutter; pathetic, I know.  But as a result, I may now take sharper afocal shots through an eyepiece, and in a split-second.  Right afterwards, I threw Polaris out-of-focus and took ten shots.  All but one were duds.  The one...

It's there.  Look sharp. 

Here, I've brightened the image...

The extra-focal and intra-focal sightings were identical.  

Now, that's with my Celestron star-prism diagonal integrated, and as it was throughout the first-light. 

I had thought about this at the time, although not pertaining to this exercise: "Can a mis-collimated diagonal cause a mis-collimated telescope to appear collimated?"  

Lastly, the Moon...

The Moon appeared there in the sky as though it had fallen into a bowl of chicken broth, floating just beneath the surface, glowing.  It wasn't very high up above the horizon...

The live view, of course, was sharper, as always.  I do want this telescope to exhibit what it's capable of, but that's not going to be forthcoming for a while I'm afraid.  There's been too much water around here.  The Mississippi River, the largest in the U.S., is about ten miles to the west of my digs.  Currently, it is at a level and longevity approaching that of its infamous Great Flood of 1927.

By the way, the mount's been sorted, mostly, and to where it's usable.  I'll be showcasing that in a bit.

[johninderby]

Sounds like you like the new scope. 🙂