Astronomy
Equipment
I have recently bought a Celestron Nexstar 4 GT telescope. This is a 4" Maksutov-Cassegrain with a computerised GOTO function mount. I bought this telescope as it was a good scope for planetery work, small and portable for getting to dark sky locations and is well suited to astrophotography. Although this is a beginner sized small telescope I publish the results I get here for comparison with other users.
The optics of this telescope result in a laterally inverted image (mirror image). I have not corrected for this in any of the images.
Lunar Eclipse 3rd march 2007
A very clear night marred only by heavy dew and a slight haze at the end of the eclipse. Here is a collage of the images I took using the Nexstar 4GT with an DSLR attached. Exposure varied from 1/500th to 15-20 seconds at totality. My scope ran out of batteries right at totality so the moon is a bit blurred, as I had to position the scope manually with no tracking. Another problem was very heavy dew, which I overcame by the rather drastic (and not recommended) method of lighting a camping gas stove under the tripod! The last 3 images I have cut out the moon from the background to remove the glow caused by the high cloud.
Lunar Occultation of Saturn 1st March 2007
I was too tired to stay up for the full event but managed to get a couple of shots of Saturn close to the moon. The photos were taken with my Fuji 5500 held over the eyepiece. Processed in Paintshop, increased brightness and contrast, unshrp mask and noise removal. Time photo taken = 02:45:09 1st March 2007
Partial Solar Sclipse 28th March 2006
Fuji S5500 with Bader solarfilm filter. 1/4sec exposure f3.1
Venus Transit
WARNING: Do not look at the sun through any kind of telescope or binoculars without an astronomical quality filter. You will severely damage your eyes and may go blind.
In the south of England we were blessed with perfect viewing conditions for the Venus transit of the Sun 8th May 2004. I observed this event using the Nexstar4 using a Celestron/Bader Solar filter. Photos were taken using a handheld digital camera placed over the eyepiece ('afocal' photography) and by attaching a Philips To-U-Cam Webcam to the camera port of the telescope.
I timed the event in order to calculate the Earth-Sun distance (1 AU). For the time I used an Oregon Scientific Radio Controlled clock synchronised to a very accurate atomic clock (anyone know where?). And I found my Latitude and Longditude by GPS.
Contact
1 05:20:15 Contact 2 05:39:53 Contact 3
11:03:38 Contact 4 11:23:40 (GMT)
I took the easy way out with the calculation and used the University of
Lancashire's calculator at
http://www.transit-of-venus.org.uk/TransitCalculator/UTcontactTimes.asp
From these figures I got a best estimate of 151 Million Km for the AU.
The accepted figure is 150 Million Km. Which I thought was not bad!
The
mount for the webcam was a mid-eclipse afterthought, when I remembered
I had some plastic plumbing pipes in the garage which might fit. A few
minutes later and with the help of some trusty insulating tape I had
made a makeshift mount, albeit a bit wobbly. Using the webcam I was
able to take a video of the egress of Venus from the sun. Interestingly
I did NOT witness the so-called "black-drop" effect* by eye at all.
Looking at the video there is possibly the merest hint of it but
certainly nowhere near what had been sugessted we should expect. It
seems this effect is due to the older method of projection of the image
onto card or out of focus optics (possibly the reason for its
appearence in the webcam).
* see http://skyandtelescope.com/news/article_1277_1.asp
A speeded up version of the video can be seen here: Venus egress video (258 KB)
NB:The video is an inverted mirror image.
Venus Transit:
Title: Mid
Transit
Equipment: Nexstar
4GT + Solarfilter
Fuji Finepix S5000 3MP
Eyepiece: 32mm
Plossl, Yellow filter
Exposure: Auto
Location:
Maidenhead
Date: 08
June 2004
Time: 07:52:04
Conditions:Sunny, wispy high cloud
Comments: Reduced
resolution by 50% for web display. Taken with yellow filter for effect.
Venus Transit - Ingress
Title: Venus
ingres
Equipment: Nexstar
4GT + Solarfilter
Fuji Finepix S5000 3MP
Exposure: Auto
Eyepiece: 32mm
Plossl, 2x Barlow
Location:
Maidenhead
Date: 08
June 2004
Time: 06:41:06
Conditions:Sunny, wispy high cloud
Comments: Reduced
resolution by 50% for web display.
NB: No evidence of "Tear Drop" effect.
Venus Transit - Egress
Title: Venus
egress
Equipment: Nexstar
4GT + Solarfilter
Fuji Finepix 2600Z 2MP
Exposure: Auto
Eyepiece: 32mm
Plossl, 2x Barlow
Location:
Maidenhead
Date: 08
June 2004
Time: 12:08:41
Conditions:Sunny, wispy high cloud
Comments: Reduced
resolution by 50% for web display.
Notice directly above Venus the white disturbance on the Sun. This is also seen in the main photo and was clearly visible by eye.
See also the webcam video above for the egress sequence.
Title: Jupiter
Equipment: Nexstar
4GT
Fuji Finepix 2600Z 2MP
Exposure: Auto
Eyepiece: 32mm
Plossl, 2x Barlow
Location:
Maidenhead
Date: 30
May 2004
Time: 22:55:55
Conditions: Exceptionally Clear
Comments: Very
lucky shot. Viewng was good despite being a warm evening. I was amazed
that a handheld camera shot could reveal this much detail. this gives
me considerable hope that using my webcam in a proper mount I may be
able to get reasonable images of Jupiter.
Title: Jovian Moons
Equipment: Nexstar
4GT
Fuji Finepix 2600Z 2MP
Exposure: Auto
Eyepiece: 32mm
Plossl, 2x Barlow
Location:
Maidenhead
Date: 30
May 2004
Time: 21:58:24
Conditions: Exceptionally Clear
Comments: Hope
to do better than this with a stable mount for the camera or webcam.
Title: Moon first attempt
Equipment: Nexstar
4GT
Fuji Finepix 2600Z 2MP
Exposure: Auto
Eyepiece: 32mm
Plossl
Location:
Maidenhead
Date: 30
May 2004
Time: 22:03:44
Conditions: Exceptionally Clear
Comments: My
first attempt at a Moon photo. A bit blurred at the edges, possbly due
to hand shake.
Title: Sunspot
Equipment: Nexstar
4GT + Solarfilter
Fuji Finepix 2600Z 2MP
Exposure: Auto
Eyepiece: 32mm
Plossl + 2x Barlow
Location:
Maidenhead
Date: 04
April 2004
Time: 12:40
Conditions: Sunny, clear
Comments: Camera
at approx 3/4 zoom
Title: Sun with spots
Equipment: Nexstar
4GT + Solarfilter
Fuji Finepix 2600Z 2MP
Exposure: Auto
Eyepiece: 32mm
Plossl
Location:
Maidenhead
Date: 04
April 2004
Time: 12:41
Conditions: Sunny, clear
Comments:
Comet Hyakutake:
Title: Hyakutake
Equipment: Fujica
STX1-N with 130mm Fujinon lens, tripod mounted
Exposure: 1min
Film:
Ilford 100 ASA colour print film
Location:
Haymes Observatory, Knowle Hill, Berks
Date: 27/3/1996
Time: 22:46:49 GMT
Conditions: A bit hazy as I remember.
Comments: The
photo was taken using a tripod, but since the comet was very close to
polaris there is little movement. I had forgotten when exactly I took
this photo, so I used "Starry Night" software to back track and get a
time +/- 3 mins! All I could remember was that it was taken near Easter
1996!
Comet Hale-Bopp:
Taken
by Dr Graham Warrellow. The ion tail (blue) is clearly visible.
Title: Hale-Bopp (138 million km
from the Sun and 208 million km from Earth)
Equipment: Pentax
ME Super with Tamron 135mm lens piggybacked on a 10" f10 Meade LX200 in
alt-az mode.
Exposure: 3
mins at f4
Film: Fuji
G800 Super
Location:
Ventnor Downs, Isle of Wight
Date: 5th
April 1997
Time: 2020
GMT
Conditions: Very
clear, very cold, and very, very windy (wind gusting 30-40mph)!!
Comments: Although
by no means one of the best Hale-Bopp shots it is amazing the detail
recorded. This is testimony to the stability and tracking capabilities
of the LX200, the film, and to my wife Mary whonearly got swept off
Ventnor Downs, Mary Poppin style, while trying to use a garden umbrella
as a wind shield!
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