Jump to content

Warning - another rusty PST on eBay

moriniboy

By moriniboy
in The Astro Lounge

Recommended Posts

JamesF

JamesF

Posted
Posted

What makes you call it rusty? I can't see any.

Are they known for going rusty?

Relatively recent PSTs have an objective with a blue tint.  If this one is only around two years old, that's what I'd expect to see.

Older ones can suffer from breakdown of the ERF at the front causing an effect described as "rust".  It still has value for parts, but £400 seems quite steep to me.

James

Link to comment
Share on other sites
JamesF

JamesF

Posted
Posted

I'm struggling to believe that the seller paid £700+ for it, too.  That seems fairly high even now, and if I recall correctly prices took quite a jump early last year.

James

Link to comment
Share on other sites
JB80

JB80

Posted
Posted

It's not a great deal more than I paid for mine a couple of years ago new.

None of it makes any sense, TH tend to know what they are doing and I highly doubt that 2 years ago they would of been selling very old PSTs at 700 quid even if it was to get rid of stock.

Sometimes you can make an argument that a seller genuinely does not know but this looks like deception to me.

Hopefully any potential buyer knows what they are looking at or at least comes to ask on a forum about it.

400 quid is not an amount to sneeze at.

Link to comment
Share on other sites
eid

eid

Posted
Posted

Relatively recent PSTs have an objective with a blue tint.  If this one is only around two years old, that's what I'd expect to see.

Older ones can suffer from breakdown of the ERF at the front causing an effect described as "rust".  It still has value for parts, but £400 seems quite steep to me.

James

I see. Thanks for the explanation.

Link to comment
Share on other sites
Macavity

Macavity

Posted
Posted

There seem to be (at least) two explanations. One: It's the lens "coating" that goes.

Two: It's a cemented objective and it's the "glue" that degenerates. The symptoms

do seem to start at the edges... as if something is drying out or reacting to the air? ;)

(Often wonder, but simply out of academic interest!)

Someone on CN once compiled a whole list of serial numbers of the good and bad.

If your PST was greater than the cut off you were in the clear! Regret selling mine...

Especially before the price hike. But you can get a LOT of other stuff for the price. :p

Link to comment
Share on other sites
Uplooker

Uplooker

Posted
Posted

Someone on CN once compiled a whole list of serial numbers of the good and bad.

If your PST was greater than the cut off you were in the clear! Regret selling mine...

Especially before the price hike. But you can get a LOT of other stuff for the price. :p

I can't remember exactly, but AFAIK, the cutoff point was with serial numbers above 10000. To me that PST on Ebay looks to have a completely "rusted" objective. You can still view the sun through a resulted objective, it primarily reduces the contrast of the views

Ian

Link to comment
Share on other sites
DaveGarland

DaveGarland

Posted
Posted

I recently bought a PST from Telescope House and immediately noticed something about mine. Whenever I see pictures of PSTs the brass tube always seems to have a nice "turned" finish to it. Mine seems to have a rather rubbed look to it.

ygu3yme5.jpg

Does anyone else have one like this? It all seems to perform just fine and I'm sure Telescope House wouldn't be selling duff stuff but it did strike me as odd. A bit ugly.

Link to comment
Share on other sites
Merlin66

Merlin66

Posted
Posted

Guys,

A couple of comments...

The CN serial listing was never maintained. Also many of the earlier PST were repaired under warranty and now have a blue objective (and the internal mini-ERF. An ITF (interference transmission filter))

The original objective had an ERF coating (energy rejection filter) this (like all ITF filters - both Lunt and Coronado)is prone to deterioration due to moisture ingress. If the edge seal breaks down then unfortunately there's no way of stopping it...

The original PST had a CNC turned brass ("Gold") tube, the newer versions, I believe,(to save money?) are now Gold anodised aluminium.

Hope this helps.

Link to comment
Share on other sites
DaveGarland

DaveGarland

Posted
Posted

Merlin, I may be wrong but it doesn't feel/look like aluminium but still feels like brass. The finish though looks as though it's been "rumbled". Basically when something has been poorly machined and has a scratchy surface it is put in a vibrating container of abrasive stones to rub down the surface. It just looks a bit tatty unfortunately :(

Link to comment
Share on other sites
Peter Drew

Peter Drew

Posted
Posted

All the PSTs that I have cut up for PST mods, including some early ones, have had aluminium main tubes regardless of a polished brass looking finish (much to my surprise). As far as £400 for a "rusted" PST is concerned, its value, particularly for a mod, lies in the quality of the etalon. I have had 8 s/h PSTs so far and 3 of them had outstanding etalons each of which I would have gladly paid £400 as a stand alone item. Unfortunately you can't always judged the quality until until it has been dismantled.   :smiley: 

Link to comment
Share on other sites
Adrena1in

Adrena1in

Posted
Posted

Interesting, I was looking at this PST a couple of weeks ago, and just now I see it's been listed again, "due to a timewaster".  I was a little tempted as a PST Bino was something I'd considered trying to create.

Suddenly though, I feel like maybe I was robbed by paying £465 for mine, secondhand.   :embarassed:

Link to comment
Share on other sites
Chris

Chris

Posted
Posted

Merlin, I may be wrong but it doesn't feel/look like aluminium but still feels like brass. The finish though looks as though it's been "rumbled". Basically when something has been poorly machined and has a scratchy surface it is put in a vibrating container of abrasive stones to rub down the surface. It just looks a bit tatty unfortunately :(

Mines exactly the same Dave, looks almost like its had a coat of gold hammerite! I think I would gladly pay an extra 15-20 pounds for a well machined finish although I'm so impressed with the actual PST that I have soon forgot about the aesthetics.

Chris

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.