Coronado PST Review

[daz]

Technical details first:

Aperture: 40mm

Focal Length: 400mm

Focal Ratio: f/10

Bandwidth: < 1.0 Angstrom (see here for a definition)

The blurb says that you will be able to see prominences, active regions, filaments and other surface details - we shall see.

The scope itself comes well packed in a stiff-foam package, along with a 20mm eyepiece and a small instruction leaflet. The gold tube stands out nicely against the black housing of the focus and filter workings, and is quite light to carry. Connection to a tripod is made possible via a standard camera screw thread at the base of the black housing (A). Focusing is achieved by means of a small silver knob, again at the base of the black housing (, and the image can be tuned to different features via a rotating ring ©. The focuser is only a 1.25" unit and eyepieces are held in place with nylon screw. While this does not cause any damage to an EP barrel, I would have prefered two metal screws as in a standard focuser.

So, onto actually using the scope. Initially I attached it to my camera tripod but I found this a little unstable - no fault of the scope, but it made fine adjustments tricky. I soon swapped it onto the tube rings of my 8" scope, on the HEQ5. This of course made tracking and adjusting much easier and the scope was much more stable.

The scope is thermally stable and you just pop in the EP and away you go, which is exactly what I did. I started with the supplied 20mm, which is a standard Kellner, nothing fantastic, so I swapped to my Meade 4000 20mm. The scope has a little indicator on the top of the housing to tell you where the sun is within the scope's FOV. Once you get a rough alignment to the sun, this little device works a treat.

Actually looking through the eyepiece was quite amazing. Focusing takes a little practice, and I found watching the edges to come into focus was the easiest way to do this. Any surface features can then be finely tweaked. At 20x mag (20mm EP), the sun easily fills 2/3 of the available FOV and details can be easily made out. During the time I observed, there were two sunspot groups visible(893 and 892), and these clearly stood out against the vibrant orange of the Ha filtered light. Upping the magnificationt to 40x lost no detail, but focusing required a delicate touch to get it spot on.

By adjusting the rotating ring, you can fine tune the image to other features of the sun, prominences and so on. This was fascinating watch the change in the image as I rotated the ring - prominences come into view and then fade as the surface 'orange peel' bcomes apparant. This has to be one of the most innovative designs in amateur solar observing, it really makes the sun come alive.

As I only had the scope for a short while, I felt compelled to try my hand at obtaining an image. The scope is not really designed as a imaging instrument, but astronomers are a creative bunch, and there are some fantastic images being produced by the more technically able. Still, I managed a reasonable shot (posted in the Solar section) and was pleased with my efforts.

Conclusion - I was very impressed with this little scope, Coronado have packed a lot into a small bundle, and at a good price as well (expect to pay less than £450). Their next generation series (SolarMax) offer larger apertures and narrower bandwidths, but for the solar beginner, this is low-cost entry into this fascinating field of study.

Cheers

[geppetto]

Informative report there Daz, thanks for that.

I would love one of those scopes, its on my wish list

[GazOC]

Nice report Daz, theres one up on AstroBuySell for £380 at the moment...

[OXO]

Excellent Review/Report Daz :sunny:

James

[daz]

Thanks guys. I think this is my first proper review, and you know what? It ain't easy!!!!

[MartinB]

Very interesting and well written report Daz. Looking forward to the next star party

[GazOC]

Whats the advantage of narrower bandwidths? "Cleaner" image?

[daz]

I think so Gaz. As far as I can see/tell, it would allow more surface detail to be seen

[tom.yates]

Good report Daz , very intresting read

[CELESCOPE]

excellent report Daz , looks the business does that ,

IMAGES PLEASE !!!!!!

heheheh

Rog

[FLO]

Thanks guys. I think this is my first proper review, and you know what? It ain't easy!!!!

Good work Daz

Just a pity the Sun was quiet while you had it. Some of the prominences are so spectacular they stay in the mind like the first Saturn or Jupiter observation.

[daz]

Rog - image in the Solar section

Steve - Indeed, I was pleased to get the two sunspots though, and a small prominence. Looking to invest in a 4x or 5x ready for next time I get my grubby paws on it!!