So I bought another refractor. Why?
The idea is to keep my William Optics GT-81 in London for fun grab'n'go observing in the UK and have a larger scope for serious use on the volcano in the Canaries. OK there may be a little aperture fever involved in the decision. I wanted more objective size with the best glass and a Feather Touch focuser. Research led me to the Russian optics and the APM brand.
I decided on this 100mm and ordered it directly from the manufacturer in Germany for delivery to the Canaries.
Yesterday the package was delivered. It's in the Canaries and I'm still in London...
2013-03-27
2013-03-15
Comet C/2011 L4 PanSTARRS
The last comet I saw was Hale-Bopp back in April 1997, in Basel, Switzerland. I was on a business trip and remember seeing it with my naked eyes as I walked out of a restaurant. Astronomy did not figure much as a hobby back then - no binoculars accompanied me.
2013 - now the possibility of at least two comets this year and I have the bins (old East German Zeiss 10x50) and 'scope with which to bag them - comets and weather permitting.
On Wed 13th March we Baker Street Irregulars convened for our regular monthly meeting in Regent's Park. The weather had been very changeable: bright sunny spells then drizzle then sunshine then hail then snow, all within an hour. Regardless the intrepid cohort of Irregulars were ready at the Hub at sunset for a chance to view PanSTARRS low in the west.
The Moon, showing a fine display of Earthshine and a lower bright thin crescent, was doing its best to poke through grey drifting clouds as the western skies darkened and at 18:45 we saw the comet.
Half-way between the Moon and the point on the horizon where the Sun had set, I spotted through the binoculars a rounded patch, much brighter than I had expected with a short, more diffused tail, looking like a pigeon's tail in shape! We spied the comet until it disappeared towards the horizon; some Irregulars having captured the scene on camera.
After the excitement was over we set up our 'scopes to view and show to new attendees Jupiter, Orion, open clusters and double stars in reasonably clear skies although the seeing was not good. Towards the end of the evening I observed Saturn at x80 just as it was rising close by the Euston Tower: my scope practically horizontal.
I have to say I observed more at the Hub and for longer than during the entirity of the IoW Star Party!
2013 - now the possibility of at least two comets this year and I have the bins (old East German Zeiss 10x50) and 'scope with which to bag them - comets and weather permitting.
On Wed 13th March we Baker Street Irregulars convened for our regular monthly meeting in Regent's Park. The weather had been very changeable: bright sunny spells then drizzle then sunshine then hail then snow, all within an hour. Regardless the intrepid cohort of Irregulars were ready at the Hub at sunset for a chance to view PanSTARRS low in the west.
The Moon, showing a fine display of Earthshine and a lower bright thin crescent, was doing its best to poke through grey drifting clouds as the western skies darkened and at 18:45 we saw the comet.
Half-way between the Moon and the point on the horizon where the Sun had set, I spotted through the binoculars a rounded patch, much brighter than I had expected with a short, more diffused tail, looking like a pigeon's tail in shape! We spied the comet until it disappeared towards the horizon; some Irregulars having captured the scene on camera.
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| Photo by Philip Stobbart. |
I have to say I observed more at the Hub and for longer than during the entirity of the IoW Star Party!
2013-03-13
Isle of Wight Star Party 2013
This year I decided to attend the Isle of Wight Star Party for the first time. Observing the heavens through C. London light polluted skies is difficult. Nearly all nebulae and galaxies are impossible to resolve through the city night air so I particularly keen to see as many of these DSOs as possible from the Island dark site.
Wed 6th March
Arrived on the Island on Wed afternoon after an hour's delay at Southampton ferry terminal awaiting frogman check of the ferry's propeller! All was well and arrived on Island to full cloudy sky and a little showers.Weather forecasts not great for the duration of the Star Party. Time will tell.
Thurs. 7th March
Awoke from my base in Cowes to grey skies and little drizzle. Local weather forecast for next 48 hours is 100% cloud cover.Sun sets at 18:00. Checked in with the organisers at the site in the afternoon and pitched up later after sunset in the hope of perhaps a little observing despite the gloomy weather forecast and the leaden skies.
I had a little time to introduce myself to a few of my fellow attendees, the majority of whom had travelled from the mainland to the island. This year was the first time I attended the event and I was pleased to learn a hundred astronomers had booked.
The clouds were working hard to obscure the skies so we repaired to the common room of the camping site to hear a couple of illustrated talks. The first was from Clare who showed pics of her Feb 2012 trip to see the aurora and geological features in Iceland. And David spoke of his participation in the successful attempt to create the largest mosaic photo of the Moon by a team of experienced UK astro-imagers. As David finished his talk he were informed the skies had cleared and stars were apparent! Cue a rush from the room's exit to view the heavens.
I quickly set up the WO GT-81 on the AZ4 and was soon observing old favourites, such as the Pleiades, the Beehive and the Double Cluster and was delighted the darker background of the clusters made for a far more impressive spectacle than when seen in London skies. However hunting for nebulae and galaxies was thwarted by the enveloping clouds and a little drizzle put paid to the session at approx. midnight. Considering I had not expected any viewing time I was delighted with the first day.
Fri 8th March.
Again a grey mist greeted me in the morning and did not lift all day. I arrived at the Camp as the on-site astronomers were finishing their supper and it was obvious to all that no or very little observing time would be forthcoming. So we decided to have an educational evening in the common room; to begin a Q&A session when I asked about the timing of the Star Party (owners of the campsite returning from holiday, scheduling outside school holidays and the New Moon decided the dates). The pros and cons of the best and worst astronomical accessories were discussed.After a short coffee break various imagers explained the use of their favourite software programs.
The occluded skies being unchanging made for an early exit from the site with a hope for clearer skies over the weekend.
Sat 9th March.
Sunshine breaking through early mist raised my spirits as I arose. Driving to the camp through sun-light verdant countryside maintained my delight: perhaps this weather may hold and patience would be rewarded with clear nocturnal skies.
At the Camp a few found a little time for solar observing and later I set up my scope in the 'Dob park', an area set aside for visual observing, well away from the astro-imagers, for a bout of 'show and tell'
The sunshine was welcome as we whiled away the time with astro-chat, browsing astro-jumble and observing a kestrel perched on the top of a nearby telegraph pole. But the grey skies soon returned and the mists rolled in to the park extinguishing any hope of observing that night.
Sun 10th March
The weather deteriorated. Grey skies and strong gusts of wind. What some call 'bracing'. Satellite images made for glum viewing then it started drizzling: all before lunch. I arrived at the camp late afternoon with no expectation of observing that night. Some had admitted defeat and quited the Camp in the morning. We whiled the time in astrochat over hot drinks until the time came to leave for dinner in a nearby village pub as the snow fell which for me was the finale for IoW AstroCamp 2013.
Summary
In the four nights scheduled for stargazing the appalling weather allowed for less than one hour observing. So will I return in 2014? Absolutely, in the hope of better weather and clearer skies.
My thanks go to Stephen, Bill and Gill, organisers of the event.
The clouds were working hard to obscure the skies so we repaired to the common room of the camping site to hear a couple of illustrated talks. The first was from Clare who showed pics of her Feb 2012 trip to see the aurora and geological features in Iceland. And David spoke of his participation in the successful attempt to create the largest mosaic photo of the Moon by a team of experienced UK astro-imagers. As David finished his talk he were informed the skies had cleared and stars were apparent! Cue a rush from the room's exit to view the heavens.
I quickly set up the WO GT-81 on the AZ4 and was soon observing old favourites, such as the Pleiades, the Beehive and the Double Cluster and was delighted the darker background of the clusters made for a far more impressive spectacle than when seen in London skies. However hunting for nebulae and galaxies was thwarted by the enveloping clouds and a little drizzle put paid to the session at approx. midnight. Considering I had not expected any viewing time I was delighted with the first day.
Fri 8th March.
Again a grey mist greeted me in the morning and did not lift all day. I arrived at the Camp as the on-site astronomers were finishing their supper and it was obvious to all that no or very little observing time would be forthcoming. So we decided to have an educational evening in the common room; to begin a Q&A session when I asked about the timing of the Star Party (owners of the campsite returning from holiday, scheduling outside school holidays and the New Moon decided the dates). The pros and cons of the best and worst astronomical accessories were discussed.After a short coffee break various imagers explained the use of their favourite software programs.
The occluded skies being unchanging made for an early exit from the site with a hope for clearer skies over the weekend.
Sat 9th March.
Sunshine breaking through early mist raised my spirits as I arose. Driving to the camp through sun-light verdant countryside maintained my delight: perhaps this weather may hold and patience would be rewarded with clear nocturnal skies.
 |
| My WO GT-81 on AZ4 with the AstroChair |
The sunshine was welcome as we whiled away the time with astro-chat, browsing astro-jumble and observing a kestrel perched on the top of a nearby telegraph pole. But the grey skies soon returned and the mists rolled in to the park extinguishing any hope of observing that night.
Sun 10th March
The weather deteriorated. Grey skies and strong gusts of wind. What some call 'bracing'. Satellite images made for glum viewing then it started drizzling: all before lunch. I arrived at the camp late afternoon with no expectation of observing that night. Some had admitted defeat and quited the Camp in the morning. We whiled the time in astrochat over hot drinks until the time came to leave for dinner in a nearby village pub as the snow fell which for me was the finale for IoW AstroCamp 2013.
Summary
In the four nights scheduled for stargazing the appalling weather allowed for less than one hour observing. So will I return in 2014? Absolutely, in the hope of better weather and clearer skies.
My thanks go to Stephen, Bill and Gill, organisers of the event.
2013-02-24
Aperture Fever - best avoided.
I blame star-parties for this affliction. TheBaker Street IrregularAstronomers meet each month in Regent’s Park to stare up at low cloud cover
or light-polluted skies. No, that’s not fair comment; clear skies do present
themselves in which a surprising amount of celestial objects are observable,
bringing delight to all who attend the star-party.
I first attended the Hub, the BSIA’s
meeting spot in the park, in the Autumn of 2010 soon after the group was
established. Without a telescope, just a remembered boyhood love of astronomy
instilled by Patrick Moore’s commentaries on the Apollo missions, I pitched up
to an early meeting. Soon I was fascinated with the various telescope types
members had brought along and the varied views each ‘scope provided. I remember particularly
being shown by one of the founders of BSIA my first view of the double star, Albireo, now my favourite
binary (thanks Ralph). As a gemmologist who looks at gem colour for a
living, I observed a beautiful image of turquoise blue and topaz yellow through the
eyepiece. The eyepiece was at the end of a William Optics
GT-81. I succumbed to the first symptom of fever: I HAD to buy this telescope!
 |
| William Optics GT-81 |
This refractor was manufactured by William
Optics, for some reason, as a limited run of 100: a ‘limited edition’. I managed to secure number 35 (as attested on
the base plate of the focuser) when spending time in the Canaries. On the island
I mount it on an HEQ5Pro to enjoy the exceptional skies above the cloud level.
 |
| During first set-up on the HEQ5Pro before ascent to 2300m |
.jpg) |
| Set up on the AZ4 at the Hub before night falls. |
But that aperture fever takes hold of a
weak soul. Soon or later one yearns for a something better, bigger and more
expensive. There is no antidote: one simply MUST buy something else. Being in
close contact at star-parties with other ‘scopes is, of course, the reason why
this fever spreads indiscriminately, affecting young and old, the tyro and the ‘old
hand’. At one Hub meeting when we were enjoyed exceptional skies a fellow
Irregular showed me the double
cluster through his APM refractor
(thanks Mathew). It reminded me of two groups of diamond melee scattered on a
black gem cloth! So beautiful and all from light polluted Central London skies.
I HAD to buy an APM refractor!
After my disappointment with the performance
of the Crawford focuser on the GT-81 forcing me to replace it with a WO rack &
pinion I vowed my next ‘scope shall have the well respected Feather Touch focuser. I love the
optics of the GT-81 but its original focuser did let the scope down and I
notice the latest WO scopes have R&P focusers as standard. APM provides the
option for a Feather Touch focuser. And now I have learnt about the Russian
glass used for the optics in many APM scopes. This glass is considered by many users to be better
than the Japanese glass found in most apo-refractors.
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| APM Apo-refractor |
So the decision has been made: not by my cool
head but by the aperture fever burning within. I shall order an APM 100mm apo-refractor. The WO GT-81 will be my UK scope and the APM my Canaries scope. And damn the expense!
2013-02-23
A New Addition to the Eyepiece Stable
When I purchased the GT-81 refractor in 2011 the retailer suggested and provided two
Vixen NLV eyepieces; a 20mm and 6mm. A Celestron 2x Barlow lens was thrown also into deal. Being
short sighted I wear spectacles so eye relief is an important consideration
when selecting eyepieces. The 20mm of
eye relief the Vixens provide is sufficient for me to observe comfortably
wearing glasses.
Normally I use the 20mm eyepiece, having the lower ( x24) magnification
for observing those deep sky objects (DSO) I'm interested in, particularly star clusters.
For binary star observations I start at low magnification then swap to the 6mm (x80)
for splitting multiples with small separations.
Whenever I wish to engage in planetary work I make use the 6mm and
the Barlow to observe and recently have enjoyed seeing Jupiter's Galilean moons
displayed through Central London's skies and during occasional brief periods of
good seeing observing transits and the GRS on Jove.
For lunar viewing I screw in a variable polarising filter into the
thread of the 6mm and pop it into the x2 Barlow for excellent views of the Moon
- I have a current fondness for the various features of Mare Imbrium.
This month (2013 Feb) I've decided to plug a gap in my eyepiece
range and add one with a wider field of view than the 45 deg of the 6mm and the
50 deg of the 20mm Vixens. Researching suitable eyepieces with sufficient
eye-relief I was attracted to the TeleVue range and in particular the 17 mm ER offered by
the Nagler4 12mm.
I took one on trial from my local supplier, Widescreen Centre, to put it through its paces. It’s a bit of a
beast: approx three times as heavy as my little Vixens and stands much taller
on the GT-81. Initial concerns whether my 'scope or my grab'n'go mount I use in Central London, the light but sturdy Skywatcher AZ4, couldn't take the EP's weight were allayed quickly. Viewing the waning
gibbous Moon on the first trial night provided the best lunar experience I've
ever had. Tiny craters and rilles, slightly difficult to discern with the Vixen, shot
out at me with pin-sharp clarity. The field of view of course is immense with
no apparent fall off at the edge in sharpness of the star field surrounding the
Moon.
I will be keeping the Nagler and look forward to using it on a regular basis.
2013-02-17
Asteroid 2012 DA14
I suggested the Baker Street Irregular Astronomers do something about the asteroid. That is have a bash at seeing it at a meeting. Our normal meeting spot at the Hub in Regent's Park wasn't playing ball so it was arranged the group shall meet in a school playground in Northolt to await the rock's appearence.
News was still abuzzing about the Russian event earlier in the day as I loaded the GT-81 into the ZipCar and joined the delightful traffic crawl along the A40. Earlier I had invested twenty odd pounds on the upgrade to SkySafari 3, my iPhone app. The upgrade has the asteroid data so I could track the Alt and Az co-ordinates of the speeding rock. Dialing this info on my setting circles of my AZ4 mount would be crucial for me to spot the aseroid with my GT-81.
Arriving at the school I was greeted by clouds - lots of them which hardly parted all evening. No 2012 DA14 sighting for me. The closest I came to seeing it was when the clouds parted for a brief moment so I could see a few stars in the field of view. I'd like to think one of those points of light was the asteroid but the clouds closed in too quickly so no tracking was possible. Did I really see it? I doubt it.
News was still abuzzing about the Russian event earlier in the day as I loaded the GT-81 into the ZipCar and joined the delightful traffic crawl along the A40. Earlier I had invested twenty odd pounds on the upgrade to SkySafari 3, my iPhone app. The upgrade has the asteroid data so I could track the Alt and Az co-ordinates of the speeding rock. Dialing this info on my setting circles of my AZ4 mount would be crucial for me to spot the aseroid with my GT-81.
Arriving at the school I was greeted by clouds - lots of them which hardly parted all evening. No 2012 DA14 sighting for me. The closest I came to seeing it was when the clouds parted for a brief moment so I could see a few stars in the field of view. I'd like to think one of those points of light was the asteroid but the clouds closed in too quickly so no tracking was possible. Did I really see it? I doubt it.
Photo by Guy Wells
In this photo my GT-81 points to the position where the asteroid is hiding behind London cloud. On the right I'm being interviewed by two chaps from the press interested in our merry band of amateurs.
During the evening there was lots of chatting to old and new members of BSIA and much forlorn viewing of the cloud cover. We did get to see a little of the Moon and Jupiter htrough the cloud gaps but conditions were so unfavourable to observing we cheered when a star, any star, made a fleeting appearence! All-in-all a rather a disappointing evening.
My thanks go to Paul Hill of BSIA for organising the evening at the school.
2012-10-22
New R&P focuser
After a few weeks of using the 'scope I noticed the focuser was not behaving itself. It kept sticking as I turned the coarse focusing knob. At times I had to ease the travel of the focuser by hand. This state of affairs become frustrating. Research on the web revealed my experience of the DDG Crawford focuser on the GT-81 was not unique. Setting and resetting the tension by adjusting the hex screw 'B' on the base did not resolve the problem.
My WO GT-81 is a great refractor - superb optics but the focuser was letting it down and ruining my observing pleasure.
Other owners who experienced the same problem had swapped the focuser for a better make, such as FeatherTouch. However I heard William Optics had released the GTF-81 refractor which featured a rack & pinion focuser replacing the Crawford. Other WO scopes in their range now have R&P focusers.
I sent off for one from WO and have now replaced the DDG with it.
All in all I am delighted with my 'upgrade'. Has any other GT-81 owners taken this path?
My WO GT-81 is a great refractor - superb optics but the focuser was letting it down and ruining my observing pleasure.
Other owners who experienced the same problem had swapped the focuser for a better make, such as FeatherTouch. However I heard William Optics had released the GTF-81 refractor which featured a rack & pinion focuser replacing the Crawford. Other WO scopes in their range now have R&P focusers.
I sent off for one from WO and have now replaced the DDG with it.
The coarse and fine focuser is performing well so I am delighted I swapped. There are holes on the R&P focuser casing as per the DDG where the WO RDF base shoe can be attached so I have no problems using the finder.
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