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Posts Made By: John Biretta

January 23, 2007 06:58 PM Forum: CCD Imaging and Processing/Solar System

Need help/advice: USB2.0 cameras and PCMCIA cards?

Posted By John Biretta

Hi. Got a problem with some new cameras. Maybe someone can help or
has seen it before.

I am trying to run a USB2.0 camera through a PCcard (PCMCIA) USB2.0
adapter card. The camera software does not see the camera; claims it
is not attached. When I probe the camera with the Windows Device Manager
I get "This device cannot start. (Code 10)" error message.

I get the same error on both the new Orion Star Shoot Solar System Imager
and a new Lumenera SKYnyx. I've never had any trouble with the old
ToUcam (which is USB1.1)

Computer is an IBM ThinkPad (stop laughing!). It does not have a
native USB2.0 port, so I am running it with a PCMCIA USB2.0 adapter card.
The adapter card works great on everything else -- disk drives, printers,
iPod, etc. Other details: 2.00GHz processor, 1 GB memory, tons of free
disk space. System software is fully up-to-date (Win XP Pro SP2).

I noted that the drivers for neither camera are "digitally signed"
by MicroSoft. The camera manuals claim it does not matter, though
Windows complains about it and makes it sound like a serious problem.

I've tried everything I can think of... uninstalling / re-installing
device drivers, manual driver installs, etc.

Is anyone successfully running a laptop + PCMCIA USB2 card? Time for a
new computer? Any advice would be much appreciated!

- John B.

February 23, 2007 02:27 PM Forum: CCD Imaging and Processing/Solar System

Saturn from WSP 2007

Posted By John Biretta

Heres my best effort at Saturn for WSP 2007.
It was definitly an off-year at WSP -- lots of rain, wind,
and none of the spectacular seeing from past years. Seeing
was in 1" - 2" range most of the time. Good practice for
next year....

This was my first time using the SKYnyx2-1C camera.
It seems quite good. Much fewer artifacts than ToUcam
and allows high-speed USB 2.0 output. But I'll need better
seeing to really test it out.

Details: StarMaster 16" F4.3 + 5x PowerMate + SKYnyx2-1C.
5 fps. 650 of 3600 frames. Processed in K3CCD / Registax 4.

March 9, 2007 10:22 PM Forum: CCD Imaging and Processing/Solar System

Another Saturn from WSP 2007

Posted By John Biretta


Here's another Saturn from WSP. Slightly better than
the last one I posted. This one was at 14 fps (instead of 5 fps).

StarMaster 16" F4.3 + 5x PowerMate + SKYnyx2-1C. 2200 of 7200
frames taken over 10 minutes. Processed in K3CCD / Registax 4.

BTW, I know the image scale is large on this one, but I like it!
Enjoy....

March 20, 2007 12:13 PM Forum: CCD Imaging and Processing/Solar System

Saturn HST video

Posted By John Biretta

Check out these videos. About 4 MBytes. Note shadows of
moons moving across the rings in the second video. This
is new NASA press release using some older HST data.

http://imgsrc.hubblesite.org/hu/db/2007/13/videos/a/formats/high_quicktime.mov

http://imgsrc.hubblesite.org/hu/db/2007/13/videos/b/formats/high_quicktime.mov

http://hubblesite.org/newscenter/archive/releases/2007/13/

"Your tax dollars at work...."

April 2, 2007 04:21 PM Forum: Pictures of Me and My Telescope and........

Re: Parallax HD200C GTO is born!!

Posted By John Biretta

Masterpiece! Beautiful!

April 19, 2007 04:12 PM Forum: Refractors

Re: durable doublets?

Posted By John Biretta

I am surprised this post has gone 3 hours without
more replies...

It is curious, but my experience is very much what
you might have predicted. I've seen 2 air-spaced
triplets that would pinch below 32F. The manufacture
was very good about it, and did a little extra
machining and it has been perfect ever since. I have
also seen 2 other air-spaced triplets that were
perfect -- no problems at all.

I also have one oil-spaced triplet by very respected
maker where the elements have moved side-ways over
the years and now the collimation is very bad.
I have yet to see if it can be fixed, but I am not
so sure it can be separated without breaking anything.
The scope has been well treated, but was carry-on
baggage on many flights (you might say it has
Traveled a lot), and saw many nights of freezing
temperatures in the desert or mountain peaks.
But I also have other oil-spaced lenses by the same
company and they are fine (though their travel
is extremely limited). So triplets are somewhat
hit-and-miss, perhaps due to added complexity.
Maybe 30% or 40% with some issue, at least in my
humble experience.

Petzvals are another rough spot. My data there
are four scopes, three of which had collimation
issues. Two were sent to maker and came back
in near-perfect collimation for some nominal fee.
So they are fixable.

I have never had a doublet with problems either
at low temperatures or spontaneously lose
collimation, and I have much more data on these
than triplets. I have even been able to take some
of them apart and re-space and make even better
than factory -- something I would not do with a
triplet.

I should add I am a serious star tester -- for
me scopes need to have perfect symmetrical rings
on both sides of focus, etc. Perfect Airy pattern
at best focus. Nothing else will do.

So doublets are batting 100%, triplets 60% to 70%,
and Petzvals 25%. Rather supports your conjecture.
Though indeed nearly all the scopes were fixable after
some effort. Question: so is the added trouble of
the Petzvals and triplets worth it? I would say
a definit "yes" for the added color correction.
But if I needed a scope to work 100% of the time
without factory service for say 50 years -- I think
one would have to give a nod to the doublets. I
could be happy with Vixen Fluorite for a long time.

I suppose one could wonder if exposed Fluorite and
ED elements in the doublets (as opposed to protected in
the center of a triplet) will age well, but so far there
are no problems.

OK, I will now head for the bomb shelter. See you
in a couple half-lifes. :S

June 9, 2007 08:56 AM Forum: Equipment Talk

Re: Optical testing of Big SCTs

Posted By John Biretta

I've done some tests using a 16" or 18" Dob as a collimator. In effect a pinhole is mounted at the focus of the Dob, which produces parallel light and sends it into the C14. There is some change in the collimation of the C14, but it is fairly minor. One can do foucault, ronchi, star tests, etc. in this manner. Many errors -- spherical, astigmatism, zones -- are easily seen. Of course, it also shows up any defects in the Dob optics, so you want one with good optics in it.

Coma is more difficult to probe, since there is degeneracy between collimation errors in the C14 and in the Dob, but its not really a problem. Of course, you want the Dob well collimated. But any residual collimation errors in the Dob just mean you need to tweak the C14 collimation a little when you get is out under the real stars.

Attached star test (in focus) was done in this way with a C14 and an 18" Dob as the light source. Theres an Airy disk, some rings. Slight trace of coma -- collimation not quite perfect (yet). Also some hints of astigmatism and trefoil indicated by break-up of the first ring.

I think the best test would be with the C14 pointed vertically in a double-pass test. Use a large flat over the front aperture. Probably there would need to be some careful consideration to how the flat is supported, and what effects its deformation might have. But I don't have a large flat, only a couple Dobs.

June 27, 2007 07:20 PM Forum: Equipment Talk

Re: $40k for an apo shot of Jupiter???

Posted By John Biretta

Couple years back at WSP in the Keys you could wander between
the 10" APO and C14s and compare the views on the planets.
It was clear to me that the best 10" APO was in fact the C14.
The contrast was a bit less than the APO, but the extra
aperture made up for it. They both had advantages that the
tube was sealed and observer was at the rear far from the
light path. Probably in more normal conditions back home
the C14 would get killed by cool-down issues, but in the
Keys where day/night temp. variation is only a couple degrees
it was fine. Not sure cooldown does to a big 10" APO
lens, but at least its at the top of the tube and will not
drive tube currents.

In good moments my 11" StarMaster was better than either,
but after I'd stand next to it and look in the eyepiece
for more than a minute, air currents would start to appear
from my standing there, and the view would go mushy. Somehow
it seemed like the eyepiece was always on the up-wind side.
Something you don't need to worry about in refractors and SCTs.

July 2, 2007 08:29 AM Forum: CCD Imaging and Processing/Solar System

Re: Venus 6-30-07

Posted By John Biretta

Very nice! Which camera is a ToUcam 3, is it the
Philips SPC900NC?

July 7, 2007 01:04 AM Forum: Refractors

Re: tracking past meridian...

Posted By John Biretta

I like to use the Losmandy 12" tripod extension
with the G11 on my refractors. Adds some eyepiece
height and keeps the scope out of the tripod legs.