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Date: 07 May 2007 18:58:24
From: G.T.
Subject: Mt Wilson 60" question
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It's been awhile since I've had a chance to catch up with s.a.a. but I now
have some questions about Mt Wilson. I'm heading up there with a group on
May 19. The instructions mention the possibility of photography. If anyone
here has visited the 60" scope with a camera can you let me know what's
possible? I have a DSLR and t-adapter, or is it eyepiece projection only?
I know this all hinges on time constraints, too, especially with our almost
capacity crowd.
And anyone know who will be on staff that night?
Thanks,
Greg
--
Ticketbastard tax tracker:
http://ticketmastersucks.org/tracker.html
Dethink to survive - Mclusky
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Date: 08 May 2007 22:27:13
From: Craig
Subject: Re: Mt Wilson 60" question
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Greg,
I and other OCA members rented time on the 60" last year. It was a lot
of fun. I was supposed to go back on 4/21, but we got snowed out (which
is okay as I was able to help out with Astronomy Day @ Irvine Valley
College).
I used my 20d on both a 2" T-adapter and just holding a the camera and
lens up to the EP. Both workend and toyr shots will have to be lomited
to no more than 20 - 30 secs due to the tracking issues Mike mentioned.
Still plenty of time to get a decent if not good image. We had about 11
people and were split between those that wanted to try imaging and
those that wanted to just look. We all had plenty of EP time.
Have fun with it.
Craig
--
Remove My_Skin to E-mail me.
G.T. wrote:
> It's been awhile since I've had a chance to catch up with s.a.a. but
> I now have some questions about Mt Wilson. I'm heading up there with
> a group on May 19. The instructions mention the possibility of
> photography. If anyone here has visited the 60" scope with a camera
> can you let me know what's possible? I have a DSLR and t-adapter, or
> is it eyepiece projection only? I know this all hinges on time
> constraints, too, especially with our almost capacity crowd.
>
> And anyone know who will be on staff that night?
>
> Thanks,
> Greg
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Date: 08 May 2007 20:46:57
From: Mike Simmons
Subject: Re: Mt Wilson 60" question
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On Tue, 08 May 2007 22:27:13 GMT, Craig wrote:
> Greg,
>
> I and other OCA members rented time on the 60" last year. It was a lot
> of fun. I was supposed to go back on 4/21, but we got snowed out (which
> is okay as I was able to help out with Astronomy Day @ Irvine Valley
> College).
Thank you for that, Greg! Are you coming up on 5/19 instead? Dick tells
me signups have been very slow so it's going to be a small group, or even
get canceled if more don't sign up.
Mike Simmons
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Date: 09 May 2007 18:40:53
From: Craig
Subject: Re: Mt Wilson 60" question
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Mike,
I'm thinking of going in Sept. I'd like to go 5/19 but I have plans for
that weekend already. I've heard that signups are slow. Don't know why.
Have you heard from Matt Ota?
Craig.
--
Remove My_Skin to E-mail me.
Mike Simmons wrote:
> On Tue, 08 May 2007 22:27:13 GMT, Craig wrote:
>
> > Greg,
> >
> > I and other OCA members rented time on the 60" last year. It was a
> > lot of fun. I was supposed to go back on 4/21, but we got snowed
> > out (which is okay as I was able to help out with Astronomy Day @
> > Irvine Valley College).
>
> Thank you for that, Greg! Are you coming up on 5/19 instead? Dick
> tells me signups have been very slow so it's going to be a small
> group, or even get canceled if more don't sign up.
>
> Mike Simmons
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Date: 10 May 2007 00:12:14
From: Mike Simmons
Subject: Re: Mt Wilson 60" question
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On Wed, 09 May 2007 18:40:53 GMT, Craig wrote:
> Mike,
>
> I'm thinking of going in Sept. I'd like to go 5/19 but I have plans for
> that weekend already. I've heard that signups are slow. Don't know why.
>
> Have you heard from Matt Ota?
>
> Craig.
Craig,
I haven't heard from or seen Matt in a while. I don't know what he's up to
these days.
Mike
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Date: 07 May 2007 22:43:36
From: Mike Simmons
Subject: Re: Mt Wilson 60" question
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On Mon, 7 May 2007 18:58:24 -0700, G.T. wrote:
> It's been awhile since I've had a chance to catch up with s.a.a. but I now
> have some questions about Mt Wilson. I'm heading up there with a group on
> May 19. The instructions mention the possibility of photography. If anyone
> here has visited the 60" scope with a camera can you let me know what's
> possible? I have a DSLR and t-adapter, or is it eyepiece projection only?
> I know this all hinges on time constraints, too, especially with our almost
> capacity crowd.
>
> And anyone know who will be on staff that night?
>
> Thanks,
> Greg
Greg,
I've been using the 60" and running observing sessions for others for about
20 years so I can answer your questions. In fact, I'll be running a
session the night before for OCA. Photography with a DSLR is certainly
possible with a 2" nose piece into the 2" eyepiece adapter (full size is
4"). It takes longer to focus without any lenses in the system since you
have to get the camera's CCD exactly at the focal plane to achieve a good
focus. This not only means a certain amount of hunting and many exposures
to fine-tune focus but it's sometimes even difficult to find the focal
plane in the first place with an f/16 and focal length of over 24,000mm.
The secondary mirror usually has to be moved to get the focal plane inside
the focuser so you can get the camera properly positioned, and if it's a
few feet off it's hard to know which way to move it. We haven't done
enough focal plane photography to know just where it is sometimes. Once
you get the camera focused it's simple to shoot more images or to change to
another camera. The difference in camera bodies is simple to deal with.
Remember, too, that with a huge steel telescope with that focal length the
focus will shift as the air temperature changes, especially during the
early evening when things are cooling down after the sun sets.
As you point out, though, the time it takes can be an issue. It's up to
those in your group to decide how much time will be devoted to photography.
If the group wants to do nothing but photography then that's up to them.
In fact, I'll be there the night before with a group who will spend more
time imaging with various systems. If members of your group haven't been
there a few times already, though, they might not want to give up much time
for you to take pictures. Since your group is close to capacity (according
to your post) it can take an hour to view each object (more or less
depending on where the object is located and how much time people spend at
the eyepiece, how many turns everyone takes, etc.). That doesn't allow for
many objects between the end of twilight and 1am this time of year.
Exposure times are limited by the poor tracking of the telescope and the
lack of trakcing correction right now, even manual. The upgrade project on
the 60" has successfully been completed for two of the three phases being
undertaken. The work is done during the first three months of each year
when the weather is bad anyway. The last phase will be undertaken in early
2008 and after that we'll have a computer controlling the telescope with
PEC (periodic error in the tracking has been a problem since it was built),
something like T-Point and closed loop tracking with astronomical CCDs.
I'm not sure what capabilities might be in place for DSLRs but it's
reasonable to expect something since it's a very popular way to image these
days, especially on a telescope you're using for just one night. With the
improved tracking and the light gathering power of the 60", though, the
average imager won't need any tracking correction.
Tom Meneghini will be operating the telescope for you. I think the session
director will be Bill Craig. Bill is relatively new but he had a lot of
experience using the telescope. In fact, I asked him if he wanted to train
for it because of his experience. Not many people have used a 60" a lot.
I think Gale Gant who runs the program will be there as well. I haven't
seen the final schedule for the night, though, so I can't be sure this
hasn't changed.
Mike Simmons
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Date: 07 May 2007 23:22:37
From: G.T.
Subject: Re: Mt Wilson 60" question
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Mike Simmons wrote:
Excellent, thanks for the info!
> Since your group is close to capacity (according
> to your post) it can take an hour to view each object (more or less
> depending on where the object is located and how much time people spend at
> the eyepiece, how many turns everyone takes, etc.). That doesn't allow for
> many objects between the end of twilight and 1am this time of year.
My girlfriend, well, "now just friends ex-girlfriend" arranged this
awhile back and we've filled the group with friends and a few people
from an outdoors club (5 people are hiking up from Sierra Madre so
hopefully they won't be too burnt out) we belong to. Of the people I
know all are complete newbies to astronomy so none will be imaging, and
I'm pretty sure the rest are fairly new to astronomy, too. I'll bring
my camera but it sounds like I won't use it this time.
>
> Tom Meneghini will be operating the telescope for you. I think the session
> director will be Bill Craig. Bill is relatively new but he had a lot of
> experience using the telescope. In fact, I asked him if he wanted to train
> for it because of his experience. Not many people have used a 60" a lot.
> I think Gale Gant who runs the program will be there as well. I haven't
> seen the final schedule for the night, though, so I can't be sure this
> hasn't changed.
Do you know what all you'll be viewing the night before?
On a side note I had to move from La Canada (our landlord needed our
place for housing for a nurse for his disabled son), I spent 3 months
looking for another reasonable place up there but ended up moving back
to Burbank. I haven't done much observing since I moved down here in March.
Greg
--
The ticketbastard Tax Tracker:
http://www.ticketmastersucks.org/tracker.html
Dethink to survive - Mclusky
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Date: 08 May 2007 11:56:44
From: Mike Simmons
Subject: Re: Mt Wilson 60" question
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On Mon, 07 May 2007 23:22:37 -0700, G.T. wrote:
> My girlfriend, well, "now just friends ex-girlfriend" arranged this
> awhile back and we've filled the group with friends and a few people
> from an outdoors club (5 people are hiking up from Sierra Madre so
> hopefully they won't be too burnt out) we belong to.
I ran a session once where two people *ran* up the trail. The person who
arranged it was an ultramarathoner.
> Of the people I
> know all are complete newbies to astronomy so none will be imaging, and
> I'm pretty sure the rest are fairly new to astronomy, too. I'll bring
> my camera but it sounds like I won't use it this time.
So as newbies they might not mind waiting a bit. It's the hardcore
amateurs who get antsy when people take too long. But fussing with focus
for a DSLR without lens or eyepiece might be too much. Bring it along and
talk to Tom and/or Gale. You should be able to shoot through the eyepiece
easily at least. We should have something to hold cameras for that but
it's difficult since the 4" eyepieces we use are all so different. You can
steady it with your hands and it usually works out well.
> Do you know what all you'll be viewing the night before?
No, I've had no observing list from the group yet. It depends on what
they'll want to image. Conditions can also affect how the 60" performs for
visual observing so if they're the same on your night the staff will have
my report from the night before to go by. But you'll probably get a tour
of all the best objects for a newbie group, which isn't always the same as
with a smaller scope. We usually try to get a few examples of each type of
object if they've never looked through a scope before (quite an
introduction with a 60"!).
> On a side note I had to move from La Canada (our landlord needed our
> place for housing for a nurse for his disabled son), I spent 3 months
> looking for another reasonable place up there but ended up moving back
> to Burbank. I haven't done much observing since I moved down here in March.
It takes a lot of driving to get to reasonably dark skies around here.
Housing prices are ridiculous, too.
Mike Simmons
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Date: 08 May 2007 13:28:40
From: G.T.
Subject: Re: Mt Wilson 60" question
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"Mike Simmons" <mikes@nospam.mtwilson.edu > wrote in message
news:in3gct9uv2zp$.dcgb5rbf9ux1.dlg@40tude.net...
> On Mon, 07 May 2007 23:22:37 -0700, G.T. wrote:
>
>> My girlfriend, well, "now just friends ex-girlfriend" arranged this
>> awhile back and we've filled the group with friends and a few people
>> from an outdoors club (5 people are hiking up from Sierra Madre so
>> hopefully they won't be too burnt out) we belong to.
>
> I ran a session once where two people *ran* up the trail. The person who
> arranged it was an ultramarathoner.
Kimberly had been planning to do the hike so I have done a couple hikes on
the Mt Wilson Trail with her recently. On our last one a week ago she was
struggling at the 2/3 mark so she has mostly decided to skip the hike but I
may encourage her to try it again this Friday. But if it's this hot on May
19 I hope everyone decides to skip the hike since they would be starting in
the middle of the heat rather than before it.
We got passed by many runners practicing for the big trail run at the end of
the month, and then we got passed by 3 more up past Orchard Camp who were
extending their run to the top.
>
>> Of the people I
>> know all are complete newbies to astronomy so none will be imaging, and
>> I'm pretty sure the rest are fairly new to astronomy, too. I'll bring
>> my camera but it sounds like I won't use it this time.
>
> So as newbies they might not mind waiting a bit. It's the hardcore
> amateurs who get antsy when people take too long. But fussing with focus
> for a DSLR without lens or eyepiece might be too much. Bring it along and
> talk to Tom and/or Gale. You should be able to shoot through the eyepiece
> easily at least. We should have something to hold cameras for that but
> it's difficult since the 4" eyepieces we use are all so different. You
> can
> steady it with your hands and it usually works out well.
>
>> Do you know what all you'll be viewing the night before?
>
> No, I've had no observing list from the group yet. It depends on what
> they'll want to image. Conditions can also affect how the 60" performs
> for
> visual observing so if they're the same on your night the staff will have
> my report from the night before to go by. But you'll probably get a tour
> of all the best objects for a newbie group, which isn't always the same as
> with a smaller scope. We usually try to get a few examples of each type
> of
> object if they've never looked through a scope before (quite an
> introduction with a 60"!).
Cool, some of the documentation mentions that nebulae and galaxies aren't
very impressive at this focal length but without our own list are you saying
the staff will try to get an example of each type object? After the bigger
planets I'm finding that I like globular clusters and planetary nebulae the
most.
Greg
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Date: 08 May 2007 20:44:53
From: Mike Simmons
Subject: Re: Mt Wilson 60" question
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On Tue, 8 May 2007 13:28:40 -0700, G.T. wrote:
> Kimberly had been planning to do the hike so I have done a couple hikes on
> the Mt Wilson Trail with her recently. On our last one a week ago she was
> struggling at the 2/3 mark so she has mostly decided to skip the hike but I
> may encourage her to try it again this Friday. But if it's this hot on May
> 19 I hope everyone decides to skip the hike since they would be starting in
> the middle of the heat rather than before it.
And the upper portion is where it's so open that you can really get
dehydrated.
> Cool, some of the documentation mentions that nebulae and galaxies aren't
> very impressive at this focal length but without our own list are you saying
> the staff will try to get an example of each type object? After the bigger
> planets I'm finding that I like globular clusters and planetary nebulae the
> most.
Most *diffuse* nebulae and galaxies are less impressive than you'd expect.
Planetary nebulae are unbelievable. It's a question of contrast. With a
galaxy that extends out of the field (as most bright ones do; maximum field
is 11 arcminutes) there's often very little contrast in the galaxy and the
edges blend into the moderate light pollution from the valley below. Same
with many diffuse nebulae. Exceptions include galaxies that have a
prominent dust lane like M104, NGC 4565 or NGC 891. The contrast with
those is provided by the galaxy itself. And diffuse nebulae with details
like M42 are incredible (not that there are many "like M42"). You may not
think of planetary nebulae as having a lot of detail based on observing
them in smaller scopes but with the 60" there's a lot to see if the seeing
is decent.
If the clouds move in from the coast and block the lights from LA then
there's a lot more to see. But there's plenty within range of the 60"
anyway. The bigger question most of the time is what sort of seeing you
might have. There's plenty of light if you're observing a bright planetary
nebulae so what you want to see is the finer detail that you ordinarily see
only in photos from Hubble or another big scope. Good seeing is what's
required for that. Same with globular clusters, which can be fantastic
with so many stars very bright and clearly resolved. Poor seeing mushes
them together. Minimum power with the biggest eyepiece we have, a 100mm
Kellner in 4" barrel, is 248x but with good seeing you can go to several
multiples of that on many objects. Sub arcsecond seeing is common on Mt.
Wilson and with a 60" there can be a lot to see.
They'll pick objects and eyepieces based on experience with the scope and
different conditions. But feel free to request whatever you want -- it's
your scope! They'll advise you on whether or not it might be worth the
time and trouble. If there aren't any requests -- and especially if it's
mostly newbies -- they'll probably give a general survey of what's up,
using the best representatives of the different types of objects. We often
do that for classes as well.
Mike Simmons
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