Date   

Re: Software wish list

Chris Curran <curran.chris@...>
 

Tom,

And some of you guys think you have a "fast" telescope.... Ha! :) If
you like that, I'm working on a 10" f/5 newt that's going to look like
a Budweiser can when I'm done! :)

cheers & beers,
Chris

--- In ap-gto@..., "tucstargzr" <tucstargzr@...> wrote:

Heh, all you need now is to paint a race car on the outside of your
blind to go with the decal on the dew shield. ;-)

Tom


Re: Software wish list

Chris Curran <curran.chris@...>
 

Rick,

Flashlights: Thanks, but my problem has never been not owning enough
flashlights, it's that Maxwell seems to always know when I'm going to
need one! Really, it's a big joke around my family when it comes to me
and flashlights. I have at least three of all kinds (neck, wrist,
finger, hat, head, clip-on, slip-on, scuba, a few I've made, etc).

Blind: Yes, it's that 4'x8'x2" foam board from the local home center
(cut to 6' lengths). I used 3" duck tape for the hinges. I have to
re-tape it about once a year, but other than that has been
surprisingly durable. As long as I tie it down at the ends and
anchor/support the middle it's handled 20 to 25mph winds (best guess).
I've got loose piece that I place over the top at one end where I sit
to keep the cold air off my neck during the winter. Other benefits are
that it's very light (~20lbs) so I can fold it up and toss it on my
shoulder to move it around. At 6' it fits nicely on the shelf at the
back of my travel trailer or in the bed of my truck. It's really one
of my most versatile astro tools... :)

Psst: I tried the PVC frame type, but after making one, I decided I
was too lazy to do all that measuring and cutting and gluing, so I got
the foam panels and some duck tape. I guess that's the redneck leaking
out of me... :)

cheers & beers,
Chris

--- In ap-gto@..., "Rick Wiggins" <rickwiggins@...> wrote:

Hi Chris,
That looks pretty slick. Looks like duck tape and foam insulation
boards. Is it only duck tape that you used as hinges? How does it
perform in wind? I guess you could make some guy lines and anchor
with stakes for light winds.
Thanks, rick


ASTROVID FireballCam all sky camera

Yves Laroche
 

Hi to all,

Is there somebody here that have experience with the ASTROVID FireballCam
(All sky camera configuration with fisheye lens) for clouds monitoring
during the night? Does the integration time is enough to show high altitude
clouds ?

Thank you very much,

Yves Laroche


Re: Software wish list

tucstargzr
 

Heh, all you need now is to paint a race car on the outside of your
blind to go with the decal on the dew shield. ;-)

Tom

--- In ap-gto@..., "Chris Curran" <curran.chris@...> wrote:

:)... You're OK. I have this for star parties and what-not to block
light, wind, smoke, etc: http://www.planetcurran.com/blind.php

cheers & beers,
Chris


Re: Software wish list

Jeff Young <jey@...>
 

I hear ya, Chris. I think this would be a feature mostly for the next generation of users. ;)

-- Jeff.


From: ap-gto@... [mailto:ap-gto@...] On Behalf Of Chris Curran
Sent: Friday, September 12, 2008 11:13 AM
To: ap-gto@...
Subject: [ap-gto] Re: Software wish list


Jeff,

I dunno. I stink at text messaging - ask my daughter, she'll tell you
just how bad I am at it! :) I don't think it's something I'll ever get
good at. Maybe if it was T9 vocabulary... ???

cheers & beers,
Chris

--- In ap-gto@...<mailto:ap-gto%40yahoogroups.com>, Jeff Young <jey@...> wrote:

I think Richard's second suggestion is already being acted upon.

However, I had a thought about his first: as text messaging becomes
more popular, more and more people know the mapping from number keys
to letters (2 = a, 22 = b, 222 = c, 3 = d, 33 = e, etc.) You could
hook it up so that the number keys jumped into the star list at that
point in the alphabet.

-- Jeff.


Re: Software wish list

Joe Zeglinski
 

Hi,

One more off topic lead - I saw an "ear mount" white LED flashlight, with push button switch, for about $2 in a grab bin, at a local job shop (Princess Auto, in Canada). This flashlight is about the size of a hearing aid plug. It clips around the ear like a cell phone headphone. I considered replacing the LED with a red one, but I personally don't like things hanging around my ear - especially since it is not padded, just a plastic ring. Still, it is a very good idea. Swap out the LED and slip on some tubing as ear padding, and you have a perfect solution.

Joe

----- Original Message -----
From: <kgkirkley@...>
To: <ap-gto@...>
Sent: Friday, September 12, 2008 11:53 AM
Subject: Re: [ap-gto] Re: Software wish list



In a message dated 9/12/08 10:15:10 AM, rickwiggins@... writes:


I understand your desire to have a handy flashlight.
Let me offer a few alternative and much cheaper solutions.
Segway.....into flashlights.

I've been into flashlights all my life.....all kinds....but for astronomy and
imaging you can't beat a headlamp. A headlamp allows you to use both hands
and your mouth for their intended purposes.
I usually wear one all night or whenever I'm out in the dark with the gear
and it's alway handy.

I used to use various 'regular' flashlights in my pocket, on lanyards, in my
mouth, etc.
I got tired of salavating all the time.

There are a lot on the market designed for cavers, camping and mountaineering
but I've found the best for our use is the inexpensive (about $10) GE
Energizer headlamp which has two white and one red led.
It is tiltable so one can put the light where you need it. It runs for a long
time on 3-AAA's and is light weight.
You can find them at Walmart, Target, etc.

Kent Kirkley



**************
Psssst...Have you heard the news? There's a new fashion blog,
plus the latest fall trends and hair styles at StyleList.com.

(http://www.stylelist.com/trends?ncid=aolsty00050000000014)




------------------------------------

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Re: Software wish list

Wiggins, Rick
 

Hi Chris,
That looks pretty slick. Looks like duck tape and foam insulation
boards. Is it only duck tape that you used as hinges? How does it
perform in wind? I guess you could make some guy lines and anchor
with stakes for light winds.
Thanks, rick

--- In ap-gto@..., "Chris Curran" <curran.chris@...>
wrote:

:)... You're OK. I have this for star parties and what-not to block
light, wind, smoke, etc: http://www.planetcurran.com/blind.php

cheers & beers,
Chris

--- In ap-gto@..., "Joseph Zeglinski" <J.Zeglinski@>
wrote:

So ... Chris ...

I guess that rules out my using those 3 luminous pancakes I
bought as
vibration pads for my Losmandy G11 tripod.
Probably could die of radiation poisoning.:-)

Joe


Re: Software wish list

Wiggins, Rick
 

Hi Chris,
I understand your desire to have a handy flashlight.
Let me offer a few alternative and much cheaper solutions.

1. This is the one I use. I have several small red flashlights
including tiny Gerber ones with 1 AA baterry. They are all on
lanyards. I put one around my neck around an hour before dark and
leave it there all night. Many times I need both hands, so I hold
the flashlight in my mouth (might be a bit sporty to hold the
handcontroller in my mouth). I keep a second one by my laptop
(although a use a red gooseneck LED to light my keyboard) and a
third one in my car or in my warming room if I at at the
observatory. I stock spare flashlights and batteries (very handy for
those Murphy moments and when I have guests). P.S. I keep a backup
red and white flashlight in my car glove box (in addition to the
other one in the car) for those Power Murphy moments.
2. Keep a spare flashlight clipped to your pier.

I would not want to use the handcontroller as a flashlight due to
the cord and potential for catching it on something while digging
around on the ground looking for something.

Just some alternative views as food for thought.
Thanks, Rick

--- In ap-gto@..., "Chris Curran" <curran.chris@...>
wrote:

I don't "hang" my controller on it's hook. I have some of that 2"
industrial velcro on the back of my controller and at various
places
on the pier. I just "stick" it. I'd like the red led for use as a
flashlight - for when I drop stuff on the ground and my real
flashlight it back at the laptop. Say you're trying to adjust that
PAS
reticle and you drop that 0.9mm black hex wrench on the ground....
Yea, I did that and by the time I got back with light, it was too
late. :)

I have plenty of bubble/other levels. I'd just like to have
it "built
in" so I didn't have to find it each time I setup. I suppose I
could
epoxy one to the mount...

Luminous white paint? Really? Please don't setup next to me. :)

cheers & beers,
Chris

--- In ap-gto@..., "Joseph Zeglinski" <J.Zeglinski@>
wrote:

Hi Chris,

I would second your wish for the "red light". I think it
should be
pointed up from in front of the keypad hook, since I find it
hassle
to poke
around in the dark trying to attach the BLACK ring onto a mating
hook on the
mount. That requires two hands as I end up doing it by feel -
much more
difficult with gloves on.

To solve my own problem - for lack of a red LED - I plan on
"painting
the AP keypad hook" with luminous white paint used for fishing
lures. If
the keypad hook were made of clear plastic material, a backward
(not top)
pointing red LED could both light up the hook with "edge-
lighting", and
provide a back pointing lamp when you need to check something
with
it, and
avoid it pointing upward at the scope.

As for item #1, the bubble level, I bought one of those cheap
two axis
bubble levels ( visit Scopestuff) - the one that is on a flat red
plastic
triangle plate - and simply place it approximately on the AP
base plate
pivot point, or flush against the azimuth adjuster block, for a
more
convenient viewpoint.

Joe

----- Original Message -----
From: "Chris Curran" <curran.chris@>
To: <ap-gto@...>
Sent: Thursday, September 11, 2008 11:49 AM
Subject: [ap-gto] Re: Software wish list



I have two suggestions for upcoming AP mounts though:

1) A bubble level built into the base of the mount.
2) a red led light built into the hand controller.

cheers & beers,
Chris


Re: Software wish list

Wiggins, Rick
 

Hi,
YES! That would be a useful tool. I have a level I keep in the box
with the AP cables etc., but having one that didn't require me to
shine a flashlight to use would be icing on the cake!
Thanks,
Rick

--- In ap-gto@..., Chuck Hancock <cdh59@...> wrote:

I'd like to have a luminescent 6" straight level included w/ the
mount,
rather than a bubble level. That way one could use it for
resuming from
park on initial setup, as well as leveling the tripod AND the
mount. If
you could implement this in the software, that would be OK, too.
Oh,
and a coffee maker on the larger mounts, if it could be used for
tea as
well. :)
Clear skies,
Chuck

Chris Curran wrote:
Richard,


2. A "calibration" facility within the software to overcome
Just curious: how does a non-ortho scope impact me? None of my
scopes
are ortho and I never have a problem with guiding. Is it
pointing?
Isn't AP already working on that (or have I misunderstood what
AP is
planning with 'modeling')?


I imagine that a facilty to polar align using reference stars
would be very welcome by some users.
My 1200 does this now. You point at a reference star, change the
meridian setting in the hand controller, then re-goto that same
star.
Adjust alignment. Repeat. It's pretty darn simple (and very
accurate).
Works in the northern or southern hemisphere. What improvements
should
be made to this?

I have two suggestions for upcoming AP mounts though:

1) A bubble level built into the base of the mount.
2) a red led light built into the hand controller.

cheers & beers,
Chris



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Re: Software wish list OT

Kent Kirkley
 

In a message dated 9/12/08 11:21:19 AM, J.Zeglinski@... writes:


    One more off topic lead - I saw an "ear mount" white LED flashlight,
with push button switch,  for about $2 in a grab bin, at a local job shop
(Princess Auto, in Canada). This flashlight is about the size of a hearing
aid plug.  It clips around the ear like a cell phone headphone. I considered
replacing the LED with a red one, but I personally don't like things hanging
around my ear - especially since it is not padded, just a plastic ring.
Still, it is a very good idea. Swap out the LED and slip on some tubing as
ear padding, and you have a perfect solution.
I've seen these and other similiar lights that mount on head bands, hats,
etc.
The problem with them is that they are not individually pointable...; ie. you
have to move your head around to put the 'circle of light' where you want it.
This is especially problematic if you wear glasses for close focusing and
have to move your head up and down to find the right 'focus zone'.

A head lamp needs to be pointable separate from your head.
Kent Kirkley





**************
Psssst...Have you heard the news? There's a new fashion blog,
plus the latest fall trends and hair styles at StyleList.com.

(http://www.stylelist.com/trends?ncid=aolsty00050000000014)


[Non-text portions of this message have been removed]


Re: Software wish list

Kent Kirkley
 

In a message dated 9/12/08 10:15:10 AM, rickwiggins@... writes:


I understand your desire to have a handy flashlight.
Let me offer a few alternative and much cheaper solutions.
Segway.....into flashlights.

I've been into flashlights all my life.....all kinds....but for astronomy and
imaging you can't beat a headlamp. A headlamp allows you to use both hands
and your mouth for their intended purposes.
I usually wear one all night or whenever I'm out in the dark with the gear
and it's alway handy.

I used to use various 'regular' flashlights in my pocket, on lanyards, in my
mouth, etc.
I got tired of salavating all the time.

There are a lot on the market designed for cavers, camping and mountaineering
but I've found the best for our use is the inexpensive (about $10) GE
Energizer headlamp which has two white and one red led.
It is tiltable so one can put the light where you need it. It runs for a long
time on 3-AAA's and is light weight.
You can find them at Walmart, Target, etc.

Kent Kirkley



**************
Psssst...Have you heard the news? There's a new fashion blog,
plus the latest fall trends and hair styles at StyleList.com.

(http://www.stylelist.com/trends?ncid=aolsty00050000000014)


Re: Software wish list

Ladislav Nemec <nemecl@...>
 

It's late even here in CA and I made my first attempt to use the 'meridian
delay' method with my Losmandy/Gemini G11. The Gemini Level 4 does what it
calls 'meridian flip', i.e. for stars close enough to the meridian, it moves
from east to west (and vice versa) when it determines that the move is safe
(based on stored east-west motion limits of the mount).



It kind of worked except for my difficulties to look into the finder and/or
eyepiece in one position of the flip. I'll try again using my camera to
center the star with (first) elevation adjustment and then with a pair of
stars at similar RA for azimuth adjustment. Bit too old to crawl under the
scope to look through the eyepieces.



AP manual I accessed through the links below (I think - I do not remember
recent details any longer.) has an excellent explanation of the method and
very handy list of star pairs for the azimuth adjustment.



In the meantime, I used my favorite old polar alignment method of LX200
mount with an equatorial edge: sync on a star close to meridian at moderate
DEC, move to Polaris, adjust using elevation and azimuth knobs. Back to the
previous star, center it, sync it. Back to Polaris, and so on. Two to five
iterations yield fairly good polar alignment with ANY equatorial mount.



Currently, I am recording hours of tracking errors superimposed over RA and
Dec 'drift' using PemPro. The Dec 'drift' (result of imperfect polar
alignment) is usually pretty monotonous, mostly a straight line. RA 'drift',
however, is rather bumpy because, I believe, imperfections of the RA gear
(sidereal 24 hour gear). Good to know where the 'sweet' spots of your RA
gear are.



Probably a non-issue for AP mount owners, sorry for even mentioning it here.



Thanks for your comments but I believe I am on the right track.



Gemini calls pointing to the same object from the other side a 'Meridian
flip' - I think it is equivalent to somewhat more involved 'meridian delay'
mentioned in the AP manual.



Best,

Ladislav Nemec

Big Bear, CA

-----Original Message-----
From: ap-gto@... [mailto:ap-gto@...] On Behalf Of
Chris Curran
Sent: Friday, September 12, 2008 3:09 AM
To: ap-gto@...
Subject: [ap-gto] Re: Software wish list



Ladislav,

"Meridian Flip" typically means something else - usually you're
telling the software that your scope has moved from one side of the
mount to the other for guiding purposes. When I "flip" sides, I
recalibrate so I never use this feature.

I'm guessing that if your GOTO mount calculates and uses LST, you
could adjust the LST in your mount and use the MD method. I've also
got an EM-200 mount that I never did figure out how to use the MD
method with - there's no time setting.

If you figure something please out let us know...

cheers & beers,
Chris

--- In ap-gto@yahoogroups. <mailto:ap-gto%40yahoogroups.com> com, "Ladislav
Nemec" <nemecl@...> wrote:

One should, indeed, do his quick search before asking a question
here. It
appears that the method described in detail in one of the AP manuals
can be
used for Gemini Level 4. I never tried that but, apparently, as long
as the
same object can be reached from both east and west from meridian, a
command
'Meridian Flip' appears on the Gemini Quick Menu. Actually simpler than
described in the AP manual. In about 5 hours I'll try that.



Again, my apologies for being off-topic here but Rolando certainly
gives a
good advice, not only to AP users.



Best,

LN


Re: Software wish list

Chris Curran <curran.chris@...>
 

Jeff,

I dunno. I stink at text messaging - ask my daughter, she'll tell you
just how bad I am at it! :) I don't think it's something I'll ever get
good at. Maybe if it was T9 vocabulary... ???

cheers & beers,
Chris

--- In ap-gto@..., Jeff Young <jey@...> wrote:

I think Richard's second suggestion is already being acted upon.

However, I had a thought about his first: as text messaging becomes
more popular, more and more people know the mapping from number keys
to letters (2 = a, 22 = b, 222 = c, 3 = d, 33 = e, etc.) You could
hook it up so that the number keys jumped into the star list at that
point in the alphabet.

-- Jeff.


Re: Software wish list

Chris Curran <curran.chris@...>
 

Ladislav,

"Meridian Flip" typically means something else - usually you're
telling the software that your scope has moved from one side of the
mount to the other for guiding purposes. When I "flip" sides, I
recalibrate so I never use this feature.

I'm guessing that if your GOTO mount calculates and uses LST, you
could adjust the LST in your mount and use the MD method. I've also
got an EM-200 mount that I never did figure out how to use the MD
method with - there's no time setting.

If you figure something please out let us know...

cheers & beers,
Chris

--- In ap-gto@..., "Ladislav Nemec" <nemecl@...> wrote:

One should, indeed, do his quick search before asking a question
here. It
appears that the method described in detail in one of the AP manuals
can be
used for Gemini Level 4. I never tried that but, apparently, as long
as the
same object can be reached from both east and west from meridian, a
command
'Meridian Flip' appears on the Gemini Quick Menu. Actually simpler than
described in the AP manual. In about 5 hours I'll try that.



Again, my apologies for being off-topic here but Rolando certainly
gives a
good advice, not only to AP users.



Best,

LN


Re: Software wish list

Chris Curran <curran.chris@...>
 

:)... You're OK. I have this for star parties and what-not to block
light, wind, smoke, etc: http://www.planetcurran.com/blind.php

cheers & beers,
Chris

--- In ap-gto@..., "Joseph Zeglinski" <J.Zeglinski@...> wrote:

So ... Chris ...

I guess that rules out my using those 3 luminous pancakes I
bought as
vibration pads for my Losmandy G11 tripod.
Probably could die of radiation poisoning.:-)

Joe


Re: Software wish list

Richard Kinsey
 

Hi Jeff, having previously used a system where the reference stars
are numbered, I found that it does make searching the list for a
particular star a lot easier and quicker.
Whether or not my second suggestion is already being acted upon seems
to remain a bit of a mystery.

Cheers, Richard
--- In ap-gto@..., Jeff Young <jey@...> wrote:

I think Richard's second suggestion is already being acted upon.

However, I had a thought about his first: as text messaging
becomes more popular, more and more people know the mapping from
number keys to letters (2 = a, 22 = b, 222 = c, 3 = d, 33 = e, etc.)
You could hook it up so that the number keys jumped into the star
list at that point in the alphabet.

-- Jeff.


From: ap-gto@... [mailto:ap-gto@...] On
Behalf Of Richard Kinsey
Sent: Thursday, September 11, 2008 10:12 AM
To: ap-gto@...
Subject: [ap-gto] Software wish list


GPS is probably the last thing that I would like to see on my
AP1200.
However, I can think of a number of "refinements" that I would like
to
offer as constructive comments for consideration.

1. Numbering of the reference stars. If the reference stars were
numbered, instead of having to scroll through the list to find an
individual star, this would enable the user to quickly select stars
at
any point in the alphabetical list. No one is going to remember the
number of every star, but the idea is that knowing there are say 50
stars on the list, entering 35 quickly puts the user three quarters
the
way through the list close to the required star and then the next
and
previous keys can be used to find the exact star. In practice one
soon
remembers the numbers of stars used on a regular basis and these
can be
selected immediately by entering their number on the keypad.

2. A "calibration" facility within the software to overcome the
effect
of a non-orthogonal telescope. I appreciate that shimming the
telescope
obviously overcomes this problem. However, with over 100lbs of
telescope on my AP1200, shimming has become very difficult in
practice.
A facility within the software to "calibrate" the mount using
reference
stars on each side of the meridian would be very useful indeed.

The only other thing that I would say, bearing in mind Gerald's
difficulties in polar aligning in the southern hemisphere, is that I
imagine that a facilty to polar align using reference stars would be
very welcome by some users.

As I have previously said, the above are intended as constructive
comments for discussion/consideration.

Thanks, Richard

--- In ap-gto@...<mailto:ap-gto%40yahoogroups.com>,
Gerald Sargent <sargentg@> wrote:

I think that this topic has been exhaustively covered,
clearly fixed location users do not feel they need
anything more, and the minority portable users are
not all in accord. I do hope that the moderator will close
this topic now
For Roland, yes I do understand what you are saying,
ten minutes of time allows 150 nautical miles of rotation
at the equator, etc.


[Non-text portions of this message have been removed]


Re: Software wish list

Poschinger Konstantin v. <KPoschinger@...>
 

Hi Roland,

the thing with the star in the zenith is very good. I haven't read it
in the manual. You should add it there.

Konstantin


Konstantin v. Poschinger

Hammerichstr. 5
22605 Hamburg
040/8805747
01711983476

Am 12.09.2008 um 02:13 schrieb chris1011@...:

In a message dated 9/11/2008 6:09:55 PM Central Daylight Time,
llp41astro@... writes:

#1. In adjusting azimuth you say you can use the same star used for
altitude to move back to, which you said earlier in the description
should be near the meridian. Then you say after going to a second
star you move back to the one near the zenith. You never mentioned
the star should be near the zenith earlier. Did you mean meridian?
I usually use the star near the Zenith, near or on the meridian for
the first
step. If you use this for the second step, you will not change its
position
on the crosshair as you adjust the azimuth angle (simply because its
directly
overhead).


#2. In the Keypad manual to make the azimuth adjustment, it says to
select two stars in the east or west with similar right ascension
values. Your description here is different since you say you can use
for one of the stars the one used for altitude adjustment. Will
either way work the same?
Think about it. You can realistically use any star in any direction
if you
start with the one at the Zenith.

Rolando

**************
Psssst...Have you heard the news? There's a new fashion
blog, plus the latest fall trends and hair styles at StyleList.com.

(http://www.stylelist.com/trends?ncid=aolsty00050000000014)





Re: Software wish list

drgert1
 

Hi Roland,

--- In ap-gto@..., chris1011@... wrote:
...
I think people have trouble with my meridian delay method because
they never
try it. Maybe they read it in the manual, and conclude that it is
somehow very
complicated. It is indeed the simplest method available to you.
...

I use this method every time in the field when I setup and it works
like a charm. The closer the star is to the meridian the better the
result is as any residual azimuth error will be minimized there. Then,
who wants to flip the scope when >2hrs off the meridian? ;-)

It was interesting t read your azimuth method, too. I hadn't know of
it and just used a drift method in the south. Quite practical if one
just has the star for the altitude adjustment still sitting there.
From when I see the first star to when I'm aligned it's not even fully
dark.

Clear Skies,
Gert


Re: Collimation of AP refractors

dalebranlund
 

Hi Group,
 
I visually tested the re-collimation procedure with the AP-155 via star testing.  Here are the results:
 
1)  Nice views of Jupiter, its bands and its moons using 200x power
2)  Easily split the Double-Double at 200x power
3)  Nicely centered diffraction rings on both sides of focus using Vega at zenith.  No adjustment was indicated.
 
I am very satisfied with the visual performance and will test the scope with my image train during the next new moon.
 
I did not hear from AP on the re-collimation procedure?  Any other suggestions or a different approach from AP (or others) is appreciated?
 
Dale

----- Original Message ----
From: dalebranlund d.branlund@...
 

To: ap-gto@...
Sent: Tuesday, September 2, 2008 12:48:00 PM
Subject: [ap-gto] Collimation of AP refractors


Hi Group,

This post discusses refractor re-collimation after mechanical changes
to my AP 155 OTA. I have a few questions about re-collimation.

I changed the focuser on my AP 155 EDFS from the 2.7" focuser to the 4"
focuser. The focuser is attached to the OTA via six cap head screws so
it is relatively simple to change out the focuser.

I wondered about the alignment of the focuser relative to the optical
axis of the OTA, so I inserted a laser collimator (Howie Glatter's 2"
model) straight into the 2.7" to 2" AP adaptor (3 thumb screw model).
With the new OTA/focuser assembly, the focuser was misaligned so that
laser spot did not emerge on the objective's optical axis. To see the
misalignment, I made a precision paper target with crosshairs that
inserts over the objective and into the lense cell. The laser spot
shines through the paper, so it is easy to see misalignment. The
misalignment was about .1" relative to the crosshair (about .1
degree). This was easily adjusted by loosening the six cap head
screws, adjusting the focuser's position, and retightening the cap head
screws. The laser spot is now precisely over the cross hair. I
rotated the laser collimator to different angular positions within the
AP 2" adaptor to confirm that the laser spot did not move off of the
crosshair (no wobble).

The inner surface of the objective (and outer lense surface I suspect)
reflects a small amount of light back to the laser collimator. The
reflected light can be seen on collimator's target if the objective has
any tip/tilt error. You can see this reflection on the target by
looking off-axis into the objective (don't look on-axis).

I needed to adjust one of the tip/tilt screws on the objective by 1
turn to re-align the reflection over the center of the collimator. This
corresponds to a change of 1/32" axially or .3 degrees tilt relative
the optical axis.

I was somewhat surprised that tip/tilt was off by .3 degrees tilt. I
had just photographed a rich star field using the misaligned 4" focuser
and objective tip/tilt error. Analysis of the photo using CCD
Inspector showed little collimation error (2 arcseconds)but somewhat
higher FWHM stars (3.5 arcseconds)than I am use to.

So onto star testing the re-collimated refractor in the next few days.
I will report back the results.

Questions:

1) Has anybody used this laser method for re-collimation? With what
results?

2) What method would AP recommend for re-collimation?

Thanks,
Dale



[Non-text portions of this message have been removed]


Re: Software wish list

Joe Zeglinski
 

So ... Chris ...

I guess that rules out my using those 3 luminous pancakes I bought as vibration pads for my Losmandy G11 tripod.
Probably could die of radiation poisoning.:-)

Joe

----- Original Message -----
From: "Chris Curran" <curran.chris@...>
To: <ap-gto@...>
Sent: Thursday, September 11, 2008 4:55 PM
Subject: [ap-gto] Re: Software wish list



Luminous white paint? Really? Please don't setup next to me. :)

cheers & beers,
Chris