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Crunchy crystals

Posted by on October 12th 2010 in New tricks for an old dog

On Sunday I rediscovered something in the kitchen - a couple of tins of Carnation condensed milk that I'd stashed after turning them into caramel two months ago (using the regular boil-in-the-can for two hours method). As expected, the taste is as glorious as ever, but the inadvertent ageing has allowed the formation of large sugar crystals throughout the gloop which lends a curious crunchy texture to the stuff.

I had intended to use the caramel as a cake-filling, but there's no way that this can will last that long - I'm off to find a bigger spoon!

They Do It With (hyperbolic) Mirrors

Posted by on October 11th 2010 in Astrostuff, Shiny new kit, Thanks
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I wouldn't have bought this if it hadn't been on offer and if I hadn't managed to get a further significant discount.
It takes up less room on the mount than the big black 8-incher does and it doesn't catch the breeze so much, so it's a lot more stable.
Add to that the facts that it's lighter, more portable and gives a much bigger flat-field for imaging, and it was a no-brainer.

 

 

For those with an interest in such things, it's a GSO GSRC6M 6" f/9 Ritchey-Chrétien Astrograph as supplied by Teleskop Service (as opposed to the Astro-Tech version marketed by Astronomics). The Ritchey-Chrétien design is favoured by many professional observatories (including the Hubble Space Telescope) and by some high-end amateurs for many reasons (the absence of any refractive elements, the fixed primary mirror, the coma-free image capability etc.) but until recently they had been expensive beasts compared to other Cassegrain designs. I've wanted one for many years and when the chance to get one came along I grabbed it with both hands.

FWIW, here are some of the specs:

  • Design: True RC (Ritchey-Chrétien) with a hyperbolic primary and a hyperbolic secondary mirror. No glass corrector plates or lenses in the optical train
  • Aperture: 6" (152mm), Focal Length 1370mm, Focal Ratio f/9
  • Primary Mirror: BK7- surface quality 1/12 Lambda or better, 99% dielectric high-reflectivity coating
  • Secondary Mirror: BK7, 99% dielectric high-reflectivity coating. Robust collimatable cell. Complete obstruction = 77mm
  • Construction: Steel tube with alloy primary and secondary mirror cells. Total weight 5.4kg
  • Focuser: Axially-rotatable 1:10 dual-speed Crayford focuser for extremely smooth focusing with no image-shift, accepts 2" and 1.25" accessories

Just in case you were wondering, it is currently on offer discounted from 898 Eur to 499 Eur including tax... suffice to say that a polite request to TS resulted in a favourable deal at a much-reduced total cost and including a GSRCV50 50mm spacer placed between the focuser and the telescope. At this point I must thank Wolfi Ransburg of TS for the great deal - thanks, Wolfi!

Typically, we've had cloudy nights here ever since the thing arrived 🙁

Observing Report 29th-30th September 2010 (Much wetness)

Posted by on October 1st 2010 in Astrostuff, Observing Reports, Pics
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Wednesday evening was unexpectedly clear after several days and nights of grotty weather, and I wasn't going to miss the opportunity to get a look in so yet again I got set up after our weekly evening shopping trip. The seeing was reasonable and there wasn't a hint of a breeze but the humidity was high - it was a battle against the dew all night long. It's a good job that I'd been planning for such conditions - I'd recently acquired a set of anti-dew tapes and a controller-box and I'd made a decent power-pack. Again, the aim was to get some more views of Messier objects, image a few, and to return to Comet 103P/Hartley which is getting brighter and faster.

After a few hours I'd looked at 103P/Hartley and at a few Messiers, but many of them were difficult targets as they were drowned-out by the light of the rising Moon. Bearing in mind the condensation that kept forming on the scope's secondary mirror, I managed to get fairly good digital data for the comet and for M33 (The Triangulum Galaxy). The resultant (clickable) images are as follows:

103P/Hartley, currently in the constellation Cassiopeia.
The bright star to the left of the comet is Lambda Cassiopeiae.
Subs: 30 light @ 200s, darks, no flats, ISO200.
D50 and MPCC on the C8N, guided with PHD.

 M33 (aka NGC 598), a spiral galaxy in the constellation Triangulum.
Subs: 17 light @ 200s, darks, no flats, ISO200.
D50 and MPCC on the C8N, guided with PHD.

After that I did quite fancy a good look at the Moon but I was too knackered to carry on and it was beginning to get light so I ended the session and closed the roof. Packing away was a nightmare as everything was covered with condensation - not good when there's so much electrical stuff in use!

Butterflies 2010

Posted by on September 26th 2010 in In the garden
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This year has been a better one for the range of species that have visited our garden. So far, the list of species found is as follows:

  • Small Skipper Thymelicus sylvestris
  • Large White Pieris brassicae
  • Small White Pieris rapae
  • Green-veined White Pieris napi
  • Common Blue Polyommatus icarus (these have been so vividly blue that I thought that they were the rarer Adonis Blues)
  • Holly Blue Celastrina argiolus
  • Comma Polygonia c-album
  • Ringlet Aphantopus hyperantus
  • Small Tortoiseshell Aglaise urticae
  • Red Admiral Vanessa atalanta
  • Peacock Inachis io
  • Speckled Wood Pararge aegeria
  • Wall Lasiommata megera
  • Gatekeeper Pyronia tithonus
  • Meadow Brown Maniola jurtina
  • Small Heath Coenonympha pamphilus

Again, that's not a bad list for an urban garden in the Midlands, but there are still notable absences - here's a list of species that we usually see here but which haven't put in an appearance so far this year:

  • Large Skipper Ochlodes venata
  • Brimstone Gonepteryx rhamni
  • Painted Lady Cynthia cardui (we had lots of these last year but none this year)
  • Orange Tip Anthocharis cardamines
  • Small Copper Lycaena phlaeas

40 pics so far this year, click this one to get started:

 

Review – Merrell Chameleon Wrap Slams – now with sound-effects!

Posted by on September 22nd 2010 in My reviews, Shiny new kit
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Another update on the Merrell Chameleon Wrap Slams from Fitness Footwear Ltd....

Well, they're still comfy and grippy, but there's a problem - they've started squeaking!

At first I thought it was a sole issue, but after further investigation it turns out to be due to some of the innards. In each shoe there are two fillets of support material (closed-cell padding, I suspect) beneath the lining in the areas marked in yellow in the next two pics. These fillets all now squeak whenever they are compressed, i.e. every time a step is taken. The noises started out as quiet mouse-like squeaks last week but now it's akin to walking on whoopee-cushions. It's a shame that such a good bit of kit is now ruined by this annoyance.

 

 

 

I was putting the insoles back in after taking the above pics when I noticed the sizing on the underside. I'm still trying to figure out why size 8.5 insoles have been put into size 8 shoes (that's nominal size 8, of course, as in reality they're probably 7.5s or maybe even 7s).

 

 

I'm now of the opinion that if I'd paid for these I'd be sending them back to the retailer for replacement or refund, as they're no longer fit for purpose after less than three months of generally casual use, and as Merrell have put in the wrong insoles. Sadly this would be harsh on the retailer as it is a matter beyond his/her control, being the fault of the manufacturer.

Observing Report 15th-16th September 2010 (Clusters and Comets)

Posted by on September 17th 2010 in Astrostuff, Observing Reports, Pics
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It was generally nice and clear here on Wednesday evening so I got set up pretty sharpish after our weekly evening shopping trip. The seeing was quite good although there was the threat of isolated showers. The aim was to get some more views of Messier objects and to image them if possible, and then to find Comet 103P/Hartley which is increasing in brightness for the next few weeks, and which is currently above the horizon all night long.

Despite having to shut the roof a couple of times due to spitting rain, after a few hours I'd looked at a fair range of Messiers (M31, M32, M34, M35, M36, M37, M38, M45 and M110) with the 8" scope and had acquired images of the M37 and M38 with the D50. The resultant (clickable) images are as follows:

M37 (aka NGC 2099), an open cluster in the constellation Auriga.
Subs: 8 light @ 200s, darks, no flats, ISO200.
D50 and MPCC on the C8N, guided with PHD.

 M38 (aka NGC 1912), an open cluster in the constellation Auriga.
Subs: 11 light @ 200s, darks, no flats, ISO200.
D50 and MPCC on the C8N, guided with PHD.

Then it was time to have a look-see at the comet. It was just a faint smudge visible through the binoculars and through the scope, but the D50 and scope combo picked it up quite well with 200s exposures. I stacked 10 frames and, after a lot of post-processing, ended up with this pic:

103P/Hartley, currently in the constellation Andromeda.
Subs: 10 light @ 200s, darks, no flats, ISO200.
D50 and MPCC on the C8N, guided with PHD.

 As previous but cropped and enlarged a bit.

The comet's poorly-defined and quite dim at the moment, but it should develop a better tail and become much brighter in the coming weeks - it's closest to Earth on 20th October and closest to the Sun on 28th October, and is predicted to reach naked-eye visibility around those dates. If you want to know where and when to stare, have a look at http://www.calsky.com/cs.cgi/Comets/1
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