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Bruce McGlashan wrote:

--- In OAFs@y..., attilla.danko@s... wrote:

--- In OAFs@y..., "Bruce McGlashan" <mcglashanb2@h...> wrote:

As at Mike's, there was a
colour gradient across the disk, at about a 45 angle. In the NW,

it

appeared yellow-white, while in the SE, it appeared more orangish,

with a

tinge of turquoise-blue right at the edge of the disk. Could that

be

chromatic aberration?

Its much more likely to have been caused by the atmosphere
rather than your scope. All objects when observed at low altitudes
tend to show it, its just easiest to see on planets. The real
proof is to rotate your scope. Atmospheric chromatic dispersion
wont rotate. It will always show a color separation up and down.
On a polar aligned scope, that might look like a 45 degree angle
depending on how your star diagonal is aligned.

Thanks! I'll check this out next time.

Interesting piece of trivia. The colour caused by the atmosphere came
up a while ago on sci.astro.amateur (which I spend entirely too much
time reading - except for the authors and topics I've just kill-filed)
wrt some reviews of the Takahashi Sky 90. Basically the atmosphere is
just acting like a big prism. The neat thing that someone brought up is
that there is apparently an eyepiece that someone (British I think)
where one of the lenses can be moved around so that it acts like a prism
in the opposite direction. And there was some other widget where an
actual prism got introduced in the light path to again cancel the
atmospheric effects. Personally I would be skeptical as to the final
image quality you could get - or maybe I just misinterpreted what was
being described.

by 03:00 I was getting tired and cold.

An impressive observing seesion for a weeknight.

Maybe not. I'm on vacation this week.

Ah-hah! (that's cheating!!) Lucky you.

Actually, Saturday morning I got home from Mike's and after minimal
unpacking and walking the dog (short walk) I got up to the bedroom at 4
to find my wife reading a book. Apparently she woke up at 2 and I
wasn't home and then spent her time waiting for the call from the
police... she's now threatening to get me a cell phone for my
birthday. (She and I both consider cell phones to be inherently evil
:-) Anyone have any recommendations on phones/plans for very infrequent
use?

-ad

Bruce McGlashan

p.s. In case I don't talk to any of you beforehand, I hope the
weather
cooperates tonight and on Saturday. I'm off to Toronto tomorrow, for
my
brother's wedding Saturday, so I won't be participating in any
activities
until next week.

Bruce -

I really enjoyed reading your FLO Observing Report, especially the
detailed descriptions of how you located various M objects. I felt
like I was there, targeting the red bull's eye between two stars,
changing eyepieces, estimating cluster sizes - armchair astronomy at
its best!

I, too, am a big fan of telrads. It is so satisfying to study a map
carefully, plot little triangles and lines in your head, aim the
telrad thinking "I think it's about . . . there!", looking in the
eyepiece, and - at least on lucky occasions - seeing a little smudgy
ghost of a galaxy staring back at you.

I also like to use the telrad as a preliminary step to using the
finderscope, just to make sure I'm embarking on my search from the
correct star.

BTW, you're very welcome re use of the red flashlight at previous
sessions. Glad you liked it.

Janice

--- In OAFs@y..., attilla.danko@s... wrote:

--- In OAFs@y..., "Bruce McGlashan" <mcglashanb2@h...> wrote:

As at Mike's, there was a
colour gradient across the disk, at about a 45 angle. In the NW,

it

appeared yellow-white, while in the SE, it appeared more orangish,

with a

tinge of turquoise-blue right at the edge of the disk. Could that

be

chromatic aberration?

Its much more likely to have been caused by the atmosphere
rather than your scope. All objects when observed at low altitudes
tend to show it, its just easiest to see on planets. The real
proof is to rotate your scope. Atmospheric chromatic dispersion
wont rotate. It will always show a color separation up and down.
On a polar aligned scope, that might look like a 45 degree angle
depending on how your star diagonal is aligned.

Thanks! I'll check this out next time.

by 03:00 I was getting tired and cold.

An impressive observing seesion for a weeknight.

Maybe not. I'm on vacation this week.

-ad

Bruce McGlashan

p.s. In case I don't talk to any of you beforehand, I hope the weather
cooperates tonight and on Saturday. I'm off to Toronto tomorrow, for my
brother's wedding Saturday, so I won't be participating in any activities
until next week.

--- In OAFs@y..., "Bruce McGlashan" <mcglashanb2@h...> wrote:

As at Mike's, there was a
colour gradient across the disk, at about a 45° angle. In the NW,

it

appeared yellow-white, while in the SE, it appeared more orangish,

with a

tinge of turquoise-blue right at the edge of the disk. Could that

be

chromatic aberration?

Its much more likely to have been caused by the atmosphere
rather than your scope. All objects when observed at low altitudes
tend to show it, its just easiest to see on planets. The real
proof is to rotate your scope. Atmospheric chromatic dispersion
wont rotate. It will always show a color separation up and down.
On a polar aligned scope, that might look like a 45 degree angle
depending on how your star diagonal is aligned.

by 03:00 I was getting tired and cold.

An impressive observing seesion for a weeknight.

-ad

Well, I know Attilla is waiting anxiously for this, so here goes:

Session: 2001-014
Date/time: 2001-04-18 21:00 - 03:00
Location: Fred Lossing Observatory, Almonte, Ontario.
Weather: 5 (arr) dropping to -3 (dep), calm, cloud 0/10

Present: Al Seaman, Matt Weeks, Geoff Meek, and I.

Limiting magnitude and seeing: I'm still working on this. Best I can say
is that when I arrived, and when I left, I could easily see all the stars of
the UMi asterism, so the LM was better than the last time I was there (not
saying much). After about 01:00, stars started to have a bit of a halo,
indicating (I suspect) water vapour in the sky. No moon for entire session.

Instrument: G-8 SCT, also had peeks in FLO 16" Newt and Geoff's? 10" Dob.

Observations:

1) ISS: Saw pass at 21:29. Went straight overhead and winked out at about
130. No sign naked-eye of Soyuz. This was Matt's first sighting of ISS,
my 6th or 7th. It was not quite as bright as I remember it last fall, when
I say it in twilight. Does that make sense?

2) Polaris: I managed to centre Polaris this time, by setting the RA
correctly. Could not split double, though. I suspect it was because the
OTA wasn't cooled down yet. Saw clear and active tube currents when I
de-focused. Forgot to come back to this later in the session.

3) Jupiter: Just for the heck of it. Observed with 10mm EP (200x).
Pretty mushy, since OTA still not cool. Saw 3 moons, 2 close together on
one side and 1 opposite. Turns out, IO was in transit. Didn't see it, or
its shadow, though.

4) M37: Tried locating it using procedure suggested by Roland last time
out. No luck, because I couldn't get set up on the guide stars. Reverted
to old method - telrad dead-reckoning. Hit it first try! That was my first
time finding M37. Nice OC. Matt had just been looking at it in his scope,
and commented that there appeared to be a red star at the centre of M37. I
confirmed this. He also mentioned that there appeared to be dark lanes
visible in several areas of the cluster. I could see what he meant.
Switched from 32mm EP to 10mm, to have a better look, but colour and
contrast seemed less, so gave up.

5) M36: Found it as above, telrad dead-reckoning. Much less impressive!
Maybe 40 stars visible? Very sparse too. Looked with both 32mm and 10mm
EPs. Better with wider field. Estimated size to be 15 - 20' diameter.
This was my first time seeing M36, and also the first time I've tried to
find it.

6) M38: Hopped to it from M36 using the telrad scale and Eta Aurigae as
guides. First time trying for, and finding M38. Pretty unimpressive; much
like M36. Maybe 50-60 stars evident? Estimated diameter to be 25'.

7) M3: Revisited it for maybe 4th time, just to prove I could still find
it, and to take my first careful look at it. Located it with
telrad-F/S-32mm EP, then switched to 10mm EP. Centre is best observed with
averted vision. Outer stars were distinct, but nowhere near the same as in
Mike's Obsession.

8) M13: (Her) Found in no time, although pretty dark in finderscope this
time. Not as impressive as at Mike's. Using 10mm EP. Centre is bright
like a nebula, surrounded by distinct stars. Had an impression of a dark
lane running tangentially, about 3/4 of way out. Estimated diameter: 3 -
4' for core, 7 - 8' overall. This was the second time I viewed M13, and the
1st time to examine it closely. Al showed it to me in his 10" SCT using a
Nagler EP, and then again in the 16". Nice. The Nagler EP really brought
out the stars (aperture helped, I'm sure). No dark lane evident, so it must
have been my imagination in my scope.

9) M92: Al dialed in M92 on the 18" setting circles, and we viewed it with
his Nagler EP. Very pretty. I showed him how to find M92 using Roland's
procedure. Took him a while, checking it out in my scope as he went, but he
eventually succeeded. That makes two people I've helped find it now!
Diameter of core: ~3'.

10) Eskimo Neb. (UMa): Saw it in Geoff's 10" Dob. Tried to find it in
mine using telrad. No luck. Something for later.

11) M57 (Lyr) : Ring Nebula. Found with some difficulty, despite the fact
that Matt informs me he located it for me in my scope at Mike's. I don't
remember, and didn't log it. Could not find it in the finderscope. Went
straight from telrad to 10mm EP. Faint ring of about 1 - 1.5' diameter.
Best in averted vision. No detail apparent. This was the first time I've
found M57, and I found it without a guide procedure from anyone else.

12) Mars: Observed it using 10mm EP, when it was about 25-30 above
horizon. Bright. Wondered if my new 13% ND filter would have helped, but I
was getting cold and tired, so didn't try. The red colour naked-eye was not
apparent at the EP; looked more yellow-orange. As at Mike's, there was a
colour gradient across the disk, at about a 45 angle. In the NW, it
appeared yellow-white, while in the SE, it appeared more orangish, with a
tinge of turquoise-blue right at the edge of the disk. Could that be
chromatic aberration? This was with an Orion LV 10mm EP.

13) M5 (Ser): Was familiarizing myself with this part of the sky using my
planisphere when I noticed M5 marked. Decided to go for it, even though it
wasn't one of my objectives. Located it using telrad and intersection of
lines running up from Libra and across from Serpens to Virgo. Nice globular
cluster. Diameter apparent: ~4'. Bright centre. Appeared to have a
roughly triangular shape overall?

14) M4 (Sco): Near Antares. Found it with some difficulty and help from
Geoff. Globular cluster. Few stars (relatively speaking). Faint
irregularity in core seemed apparent.

As these last, rather undescriptive notes may hint, by 03:00 I was getting
tired and cold. When Geoff started packing up, I decided to do the same.
Overall, this was a very productive and fun night. 6 first-time Messier's!
Boy, was I tired when I got home, though.

Well, I started up the download. It is set to download a couple of files
each night between midnight and 04:00 for the next week or so. We'll see
how it goes.
Rick

--- In OAFs@y..., "Mike Wirths" <mwirths@s...> wrote:

Hi all!

Anyone into coming out to Perth tonight to do some observing? Let

me know.....

clear skies 'n' apple pies

Mike

Sigh, I wish. But I have an 8:30 meeting friday morning for which
I actually need to be away.

I look forward to the observing report.


That reminds me, for the people who went, how was FLO last night?

-ad

--- In OAFs@y..., "Wagner,Rick [CIS-ADS]" <rick.wagner@e...> wrote:

Attilla:
Whence did you download the A2.0? I have been considering imposing

on Paul

Boltwood to borrow and copy his, but I believe his is only version

1.

Rick

Instructions and the FTP address can be found here:



The only problem in downloading it is that even with a fast link,
it will take a few days to download.

If there is an OAF out there with a slow link who wants a copy
of A2.0, I can make one for the cost of the CD-Rs (About $17 with
the CDRs that I use.) It takes me several days to get around
to burning the CDs. So if you have a fast connection to the net,
you might get it faster if you download it yourself.

-ad

Hi all!

Anyone into coming out to Perth tonight to do some observing? Let me know.....


clear skies 'n' apple pies

Mike

I'm planning on the Photons at Pinhey's, if it is not raining but
other things would be out as my youngest is having his 5th birthday
party on Saturday and the only thing my wife is letting me disapear
for is the Star Party. (I'm just trying to make points as she is
letting me go to TSP without the kids)

Mike


--- In OAFs@y..., jtokar@s... wrote:

I know the forecast's not looking too great right now, but if the
weather is clear on Saturday, Roland & I are planning to bring our
scope to Pinhey's Point for the public starparty. Just wondering

if

anyone else is planning to go. If so, are you interested in

grabbing

a bite to eat on Saturday before Pinhey's?? (e.g. west end Kelsey's
around 5:15 - alternative suggestions welcome, so long as windpants
and polar fleece vests constitute suitable dining attire!)

Good Food! Clear Skies!
Janice

Attilla:
Whence did you download the A2.0? I have been considering imposing on Paul
Boltwood to borrow and copy his, but I believe his is only version 1.
Rick

Hi Robert,

how much did you
pay for the program if you do not mind me asking

us$89.00.

and what mag does it go up to

It goes down to magnitude 14 or 15. However it can also read the A2.0
database which goes down to magnitude 19.2 or so. (A2.0 is free. I downloaded
a copy from the net. It's 6.5 gigabytes.) Also, when you overlay DSS images with Guide,
it effectively goes down to about magnitude 20 (the limit of the DSS images).

do not mind giving me the details

Have a look at www.projectpluto.com.

The order form is here:

Guide 7.0 does have some weaknesses. The user interface isnt the easiest to use. But the
program sure does a lot of stuff.

of it also I like to say to all on this list I have to apologize for my
spelling and punctuations

As long as we understand what you write, thats all that matters.

Clear skies.

-ad

I have been using a online robotic telescope that is in the UK some ware I
log in the sky I want to get and it e-mail me the pic' when it has done the
job but I have to wait I have been using the DDS old survey not the new one
to gather the sky detail to see if there are any new formations or stars it
is just something I love to do one day I have my own scope that will be good
enough to do ccd imaging and I do it all my self but right now I have to
rely on robot scopes to get my pic's for me and only use my little scope for
my nightly fun of looking at the night sky it is not big enough for any
serous stuff though I have been thinking do selling all my tattoo equment to
buy a bigger scope I like a 8 inch smit f10 or a 10 inch dob f6 but that is
in the future and until that time I can enjoy the sky with the DDS and my
robot scope for my work and the little one for fun {smile}how much did you
pay for the program if you do not mind me asking and what mag does it go up
to the one I am using now goes about mag 40 it says mag 50 but over 40 I
have not noticed anymore deep sky or stars joining the screen {smile} if
your program is not to expensive to buy I might like to get it to run it
hand in had with this one that is if you do not mind giving me the details
of it also I like to say to all on this list I have to apologize for my
spelling and punctuations for I know it is bad but it is the best I can do I
do use a spell checker but it misses some stuff some times o just plainly
can not figure it out lol any way thanks for the e-mail


~~{ Robert H Young }~~

pps there a quite a few of these robotic scopes out there now only problem
is there pretty slow in getting you response

ok thank you very much will do


~~{ Robert H Young }~~

--- In OAFs@y..., "Darkbeing" <darkbeing@a...> wrote:

may I ask what the direction are and if there is a map just in case
some day

Hi Robert,

I don't have any image map version of the FLO site, but if you read
message#411 by Al Seaman with the updated instructions in text format,
and you also use some kind of Ontario map, you should be able to get
fairly close to the correct location.

Rol

Yes, DSS is a wonderful thing.

My favorite way of downloading DSS images from the net is with my star-charting software
Guide 7.0 (www.projectpluto.com).

In Guide 7.0, you can zoom in on any section of the sky, and then from a menu ask it to
download the DSS image for the part of the sky you are looking at. It makes the DSS image
part of Guide's starchart, rotating and zooming it correctly. You can download as many
DSS images of the sky as you have hardisk space for. So Guide can act as a photo album
for DSS images.

DSS works really well for galaxies. I use to to check the location of UGC and PGC galaxies, many
of which have errors of several arcminutes in their cataloged location. Ive even found a few
NGCs that have been cataloged at the wrong RA/DEC.

DSS dosent work as well for planetary nebulae. For example M57 is highly overexposed.
It does reveal the rarely seen outer-halo of M57, but all the detail in the ring is lost. DSS
images is how I found the galaxy IC1296 (only 8 arcminutes from M57) which I now use as
a sky transparency test.

Make sure you have a big disk though. The online DSS image database runs of a CD-ROM jukebox
with more than 100 cds in it.

-ad

well if you still like to look at the stars and are a die hard you cna
still acess them through
this web sight all you have to do
is put in the RA and DEC of the
are aof sky you want to look at and tell it you want it in gif format and in
a few sec's it will be one your screen
in a 30 buy 30 arc min area of size or 60 buy 60 for the older sky survay
stuff i just thoughti put it up incase some of you did not know that it was
out there and that you cna acess anything anyware you want anytime you like
day of night it is a good reserch tool if you are into doing old and new
comparisions looking for diferenced in sky and for new stars mind you it is
a long and hard road to do that kind of thing but it is fun none the less
any way take care just thought you like the info


~~{ Robert H Young }~~

may I ask what the direction are and if there is a map just in case some day
I would like to show up or find somone that hasa van with a ramp that cna
take me just woundering is all