The Comet Lulin is getting brighter, and the public may soon be able to enjoy a view of the phenomenon without specialized telescopes.
Exposed for 20 minutes on February 03, 2009, 4:59 AM, 152mm f5, Canon Rebel
See also next three shots in photostream.
Comet Lulin's closest approach will be on February 24th, 2009
Mag 16 stars are easily seen in this shot, processed for "Light Pollution Reduction"
Read the news about at:
www.google.com/search?hl=en&q=comet+lulin&btnG=Go... and news.google.com/news?hl=en&q=comet%20lulin&um=1&a...
.
Dark sky view at antwrp.gsfc.nasa.gov/apod/ap090207.html
Wednesday, February 18, 2009
Tuesday, February 17, 2009
30 inch f/12 Refractor by John Wall
How does it work? See www.nightskies.net/zerochromat/products/index.html and patent below.
The inventors have found that, if a negative lens is interposed between the field lens and the corrective positive lenses, it becomes possible to greatly shorten the optical train,
Accordingly, the invention provides an optical train comprising: a positive objective lens; a field lens, located at or close to the focus of said objective lens; one or more lenses, together forming a positive lens array, located beyond the focus of the said objective lens; and characterised by the provision of at least one negative lens, interposed between said field lens and said positive lens array.
The positive lens array is preferably arranged to correct for chromatic aberration, as described below.
The field lens - to gather off-axis rays - may be mounted at the focal plane of the objective lens. However, in this case, any imperfections in the field lens, or dust and the like located on the surface of the field lens, will come into focus, and adversely affect the image quality. Therefore, it is preferable that the field lens is not located precisely at the focal point, but wherein the said field lens and the focal point of the said objective lens is less than 5% of the focal length of the said objective lens.
More preferably, the distance between the said field lens and the focal point of the said objective lens is less than 1% of the focal length of the said objective lens.
www.wipo.int/pctdb/en/wo.jsp?WO=2006123124&IA=GB20060...
----------------
The Hanwell Observatory also has a 30 inch f/6 reflector
myweb.tiscali.co.uk/hanwellobservatory/30_inch.htm#30inch
ps - The Crayford Focuser was invented by English amateur John Wall
The inventors have found that, if a negative lens is interposed between the field lens and the corrective positive lenses, it becomes possible to greatly shorten the optical train,
Accordingly, the invention provides an optical train comprising: a positive objective lens; a field lens, located at or close to the focus of said objective lens; one or more lenses, together forming a positive lens array, located beyond the focus of the said objective lens; and characterised by the provision of at least one negative lens, interposed between said field lens and said positive lens array.
The positive lens array is preferably arranged to correct for chromatic aberration, as described below.
The field lens - to gather off-axis rays - may be mounted at the focal plane of the objective lens. However, in this case, any imperfections in the field lens, or dust and the like located on the surface of the field lens, will come into focus, and adversely affect the image quality. Therefore, it is preferable that the field lens is not located precisely at the focal point, but wherein the said field lens and the focal point of the said objective lens is less than 5% of the focal length of the said objective lens.
More preferably, the distance between the said field lens and the focal point of the said objective lens is less than 1% of the focal length of the said objective lens.
www.wipo.int/pctdb/en/wo.jsp?WO=2006123124&IA=GB20060...
----------------
The Hanwell Observatory also has a 30 inch f/6 reflector
myweb.tiscali.co.uk/hanwellobservatory/30_inch.htm#30inch
ps - The Crayford Focuser was invented by English amateur John Wall
Friday, February 13, 2009
Windows 7 Beta - an education
*** Windows 7 Beta - an education ***
Attention span for Win7 ran out, driver nightmare and I don't want to mess my machine up by swapping hardware, but it was a fun two days learning 2/13/09
----- My bookmarks ---------
http://www.computing.net/answers/windows-2000/making-bootable-isos/60987.html
http://www.allbootdisks.com/iso.html
http://www.mydigitallife.info/2007/12/23/illustrative-guide-to-create-bootable-iso-image-from-vista-win-image-files/
.. from my email http://runwin7fromusb.blogspot.com/2009/01/windows-7-free-activation-keys.html
http://www.techsupportforum.com/hardware-support/removable-media-drives/341778-how-burn-bootable-iso-file.html
http://www.microsoft.com/windows/windows-7/ Win Beta 7
List of Windows 7 Secrets http://blogs.msdn.com/tims/archive/2009/01/12/the-bumper-list-of-windows-7-secrets.aspx
Windows 7 Networking http://windows7forums.com/windows-7-networking/ , http://windows7forums.com/windows-7-networking/2510-windows-networking-fixed-w7-xp.html
Is it really impossible for MS to use old WinXP drivers in the new OS ? http://windows7forums.com/windows-7-hardware/2798-drivers-general.html
Windows 7 with Hardware report, Testing 'older' parallel, USB. http://forums.scotsnewsletter.com/index.php?showtopic=21932 no go for parallel printer..
alot (if not all) of these driver/hardware/software issues will be fixed by final release
Windows 7 Beta (7022 and 7032) http://thepiratebay.org/torrent/4712592/Microsoft_Windows_7_Beta(Build_7032.0.x86fre.winmain.090115-1850 Comments
Windows 7 - impressions https://geekswithblogs.net/lvega/archive/2009/01/09/128507.aspx
Ubuntu 9.04 Alpha4 vs. Windows 7 Beta http://blog.ibeentoubuntu.com/2009/02/ubuntu-904-alpha4-vs-windows-7-beta.html (Linux)
Step-by-Step Guide to Migrating Files and Settings http://technet.microsoft.com/en-us/library/bb457074.aspx
Attention span for Win7 ran out, driver nightmare and I don't want to mess my machine up by swapping hardware, but it was a fun two days learning 2/13/09
----- My bookmarks ---------
http://www.computing.net/answers/windows-2000/making-bootable-isos/60987.html
http://www.allbootdisks.com/iso.html
http://www.mydigitallife.info/2007/12/23/illustrative-guide-to-create-bootable-iso-image-from-vista-win-image-files/
.. from my email http://runwin7fromusb.blogspot.com/2009/01/windows-7-free-activation-keys.html
http://www.techsupportforum.com/hardware-support/removable-media-drives/341778-how-burn-bootable-iso-file.html
http://www.microsoft.com/windows/windows-7/ Win Beta 7
List of Windows 7 Secrets http://blogs.msdn.com/tims/archive/2009/01/12/the-bumper-list-of-windows-7-secrets.aspx
Windows 7 Networking http://windows7forums.com/windows-7-networking/ , http://windows7forums.com/windows-7-networking/2510-windows-networking-fixed-w7-xp.html
Is it really impossible for MS to use old WinXP drivers in the new OS ? http://windows7forums.com/windows-7-hardware/2798-drivers-general.html
Windows 7 with Hardware report, Testing 'older' parallel, USB. http://forums.scotsnewsletter.com/index.php?showtopic=21932 no go for parallel printer..
alot (if not all) of these driver/hardware/software issues will be fixed by final release
Windows 7 Beta (7022 and 7032) http://thepiratebay.org/torrent/4712592/Microsoft_Windows_7_Beta(Build_7032.0.x86fre.winmain.090115-1850 Comments
Windows 7 - impressions https://geekswithblogs.net/lvega/archive/2009/01/09/128507.aspx
Ubuntu 9.04 Alpha4 vs. Windows 7 Beta http://blog.ibeentoubuntu.com/2009/02/ubuntu-904-alpha4-vs-windows-7-beta.html (Linux)
Step-by-Step Guide to Migrating Files and Settings http://technet.microsoft.com/en-us/library/bb457074.aspx
Tuesday, February 03, 2009
Comet Lulin over Los Angeles, Feb 3rd
Exposed for 20 minutes on February 03, 2009, 4:59 AM, 152mm f5, Canon Rebel
See also next three shots in photostream.
Comet Lulin's closest approach will be on February 24th, 2009
Mag 16 stars are easily seen in this shot, processed for "Light Pollution Reduction"
Read the news about at:
www.google.com/search?hl=en&q=comet+lulin&btnG=Go... and news.google.com/news?hl=en&q=comet%20lulin&um=1&a...
.
keywords:
Comet Lulin edhiker
See also next three shots in photostream.
Comet Lulin's closest approach will be on February 24th, 2009
Mag 16 stars are easily seen in this shot, processed for "Light Pollution Reduction"
Read the news about at:
www.google.com/search?hl=en&q=comet+lulin&btnG=Go... and news.google.com/news?hl=en&q=comet%20lulin&um=1&a...
.
keywords:
Comet Lulin edhiker
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