A long awaited achromat...

[Alan64]

...finally arrived.  It was shipped on the 10th of June...

The box contains an OTA only, and the box being part of a kit's package, hence the cardboard of the box being quite thin, yet the OTA was shipped in same.  I'm surprised it arrived undamaged.  The box did get rumpled a bit in transit, but the OTA was unscathed, most thankfully. 

I received the package earlier this afternoon, on the 3rd, but earlier this morning the USPS tracking stated still, "Shipping Label Created, USPS Awaiting Item..."  Also, the package was sent "Priority Mail", for which a premium is paid, but it was as though it had shipped from China.  Our postal service on this side of the pond is laughable.  I do hope the Royal Mail is quite the opposite.  I'd be aghast, quite surprised, otherwise.

It is very difficult these days to find an achromat longer than f/11, save for a 60mm f/15.  Now, in refractorland, even a seemingly insignificant increase of 2mm is in reality quite significant.

If desirous of a grab-and-go refractor, with minimal to no false-colour apparent, yet a fun and economical achromat, then one must choose a refractor such as this...

...a 70mm, 10mm extra, and at f/12.9...

I got the last one...

https://i.imgur.com/kE9FyrQ.jpg

In addition, with its 900mm focal-length, it plays ideally with the general 4mm-to-40mm range of eyepieces, and to where a 2x-barlow is quite the option, rather than a necessity.  The longer the focal-length, the easier it is to reach the higher and highest powers of which a given aperture is capable.  That's what a telescope is for in the first place, to see faraway objects up close.  Else, you'd use just your eyes or a pair of binoculars.

Its fine doublet is of good ole crown and flint glasses, tried and true, and since 1727, or thereabouts.  It is quite understandable to be proud of Sir Issac and his Newtonian...

But the achromatic-refractor was developed, invented, by an Englishman as well: Chester Moore Hall...

"Not a lot of people know that." - Benny Hill

Then, by the 1750s, John Dollond, another Englishman, began the achromat's mass-production, although still quite a long way off from today's numbers.

[A McEwan]

Congratulations on your new refractor! It looks very interesting, and would be great for solar system observing. Hope we get a First Light report soon!   

Ant

[John]

Congratulations on the 70mm F/12.9 achromat - hope you have fun with it !

I picked up a very low cost 90mm F/11.1 Celestron branded optical tube last year with similar ideas of simple, fun, lightweight observing. I must dust it down and use it a bit more !

 

[Alan64]

I got this Celestron "AstroMaster" kit about four years ago.  It came with a 70mm f/12.9 achromat...

At some point after its receipt, I began to make improvements.  I blackened and flocked the refractor, from fore to aft, and even made the lens-cell and the focusser's housing adjustable, collimatable.  But then I encountered this...

...the focusser, the manner in which the draw-tube fits into the housing, its design...

...atrocious.  Although, at the time that I got the kit, I wasn't wanting the refractor, only the EQ-1 mount.  I tried, tried, and tried to enable the draw-tube to rack in and out firmly yet smoothly, but most importantly, square and true.  I failed.  The bizarre, proprietary design is simply unworkable.  If I want to right it, I will need to contact Celestron and beg, plead, for a "PowerSeeker" 70mm focusser. 

But at present, such is not a priority, as the focusser of this new Meade is normal, traditional...

The focusser-housing and draw-tube of the Meade "Polaris" 70mm are of plastic, and unlike those of the Meade "Polaris" 90mm which are of metal, utterly...

But that came as no surprise, as they're not going to place a metal focusser on a 70mm, not at its price-point.  They're simply not taken that seriously, regrettably.

Recently, last month, Orion of California "annexed" Meade.  The kit from which this Meade achromat came has been discontinued, and is out of stock everywhere.  I didn't need another EQ-1 mount, only the OTA, which I got, and "just in the nick of time", as it remains to be seen as to what will become of the Meade product line.

There were a couple of issues with this achromat upon its arrival.  The listing described it as being "new", but I found a dead mosquito at the edge of the doublet adjacent to its plastic retaining-ring.  At first I thought it was plastic sprue, but no.  That would seem to indicate that the refractor had been outdoors at night, under the stars, to be tested at least, or simply used for observing, the Moon only most likely; perhaps Jupiter and/or Saturn.  But I'm not going to quibble over that, as this achromat is now a greatest of rarities.

Then, there's this...

...no dovetail-bar.  The bar was installed at the factory.  You can see the line there, where it was, once.  That's not an optional item, like the red-dot finder that was stated within the listing as not being included.  I have the tube-rings that I had bought for the Celestron, and a spare bar, but still.  I don't like fixed bars, but I've contacted the seller nonetheless.

In time, this achromat will be enhanced, and for a worthy addition to my collection.

[neil phillips]

9 hours ago, Alan64 said:

...finally arrived.  It was shipped on the 10th of June...

The box contains an OTA only, and the box being part of a kit's package, hence the cardboard of the box being quite thin, yet the OTA was shipped in same.  I'm surprised it arrived undamaged.  The box did get rumpled a bit in transit, but the OTA was unscathed, most thankfully. 

I received the package earlier this afternoon, on the 3rd, but earlier this morning the USPS tracking stated still, "Shipping Label Created, USPS Awaiting Item..."  Also, the package was sent "Priority Mail", for which a premium is paid, but it was as though it had shipped from China.  Our postal service on this side of the pond is laughable.  I do hope the Royal Mail is quite the opposite.  I'd be aghast, quite surprised, otherwise.

It is very difficult these days to find an achromat longer than f/11, save for a 60mm f/15.  Now, in refractorland, even a seemingly insignificant increase of 2mm is in reality quite significant.

If desirous of a grab-and-go refractor, with minimal to no false-colour apparent, yet a fun and economical achromat, then one must choose a refractor such as this...

...a 70mm, 10mm extra, and at f/12.9...

I got the last one...

https://i.imgur.com/kE9FyrQ.jpg

In addition, with its 900mm focal-length, it plays ideally with the general 4mm-to-40mm range of eyepieces, and to where a 2x-barlow is quite the option, rather than a necessity.  The longer the focal-length, the easier it is to reach the higher and highest powers of which a given aperture is capable.  That's what a telescope is for in the first place, to see faraway objects up close.  Else, you'd use just your eyes or a pair of binoculars.

Its fine doublet is of good ole crown and flint glasses, tried and true, and since 1727, or thereabouts.  It is quite understandable to be proud of Sir Issac and his Newtonian...

But the achromatic-refractor was developed, invented, by an Englishman as well: Chester Moore Hall...

"Not a lot of people know that." - Benny Hill

Then, by the 1750s, John Dollond, another Englishman, began the achromat's mass-production, although still quite a long way off from today's numbers.

I bet its very sharp. very similar to mine. As a grab and go 70mm doublets 900mm FL are bargains they can take very sharp contrasty lunar images

congrats

[Alan64]

1 hour ago, neil phillips said:

I bet its very sharp. very similar to mine. As a grab and go 70mm doublets 900mm FL are bargains they can take very sharp contrasty lunar images

congrats

Yes!  You have the "Capricorn"; same telescope, and both, undoubtedly, made by Synta.

[Alan64]

During the interim, I had ordered a dovetail-bar from China, via AliExpress, and at 152mm in length.  It arrived today in the early afternoon...

For some unknown reason, reasonably-priced bars shorter than 200mm are few and far between, over here.  The bar came with what appears to be M4 screws...

...and useless.  They don't fit anything, for my purposes.  "Ours is not to reason why..."

I located the rings that I had gotten for the other, Celestron 70mm achromat...

But then, I noticed that the base of the rings would hang off of the ends of the bar once attached...

That's not the worst thing in the world, and most of the base does fit over the bar.  My OCD, however, wants it flush.  I haven't decided yet, but I'm probably going to drill new holes inward a bit from the ends.  The bases, the rings, are actually quite wide.  There are better-grade rings that are slimmer, which would not hang over the edge.

I then went out and got mostly M5 hardware to effect the attachment of the rings...

The nuts are of the "acorn" type, like that of an oak.  Those will act as stops on the underside of the bar, and to help prevent the telescope from sliding out of the mount's saddle whilst adjusting or removing same.

In that I will be using tube-rings, these original screws that once fastened the bar to the OTA, with their heads protruding above the tube's surface, have got to go...

I also got these, which will be placed in their steads, glued in place even...

Edited July 24, 2021 by Alan64

[Alan64]

https://www.youtube.com/watch?v=b9xDvX2_v0k

 

In the end, I didn't feel the need to alter the bar.

Edited July 24, 2021 by Alan64