4 inch reflector can't resolve Mars at all

On Wed, 2 May 2007 16:36:15 -0700, "Starlord"
wrote:

I would go for a single high power EP, they do much better that the barlowed
ones do. I used my 4.8naggler EP during mars passing.


The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
The Church of Eternity
http://home.inreach.com/starlord/church/Eternity.html
AD World
http://www.adworld.netfirms.com/


wrote in message
oups.com...
On May 2, 5:21 pm, Bullseye wrote:
I have a Nexstar 114GT and it can give visuals of the moon nicely
(most scopes can I think) but I can't see sqwat when I point to Mars.
I pointed to it 1-2 years ago when it was all over the news that it
was close to Earth, but all I could see was a pink little ball, no
features at all. Also in Saturn all I could see is a tiny little dot
with a tiny circle around it. I've centered the scope and adjusted it
all the ways I'm supposed to to get the best image (I've forgotten the
exact terms that are used since I've ditched astronomy for awhile),
but trust me I did. I just want to sell this sucker and get a new one.
Can anyone recommend the best 4 inch reflectors out there for less
than $500? Or maybe a very good 8 inch dob for less than $500?

Mars will be almost overhead for north temperate latitudes this
December, although less than 16 arc-sec in diameter, so get yourself a
bigger telescope ASAP. For $500 you should be able to get an 8-inch
Dob AND a good 3x Barlow (you will probably need one.) If you can
stretch the budget a couple of hundred dollars go for a 10-inch, but
don't delay your purchase too long. Make sure you have about 30x to
35x per inch of aperture.

Practice observing Jupiter and Saturn, so that you will be ready for
Mars.


That's the term I meant to use, "collimated". I had forgotten it
because it's been a long while. I tried collimating it the cheap way.
Taking one of those small black containers that hold a roll of film,
making a small hole in the middle. Sticking a small dot in the middle
of my mirror, and trying to align it with the screws. If that's not a
good way to do it then I'll have to buy one of those laser
collimators. But I'm also thinking about just getting one of the 8"
dobs. Thanks for your suggestions.

On Thu, 03 May 2007 00:04:32 GMT, Bullseye wrote:

That's the term I meant to use, "collimated". I had forgotten it
because it's been a long while. I tried collimating it the cheap way.
Taking one of those small black containers that hold a roll of film,
making a small hole in the middle. Sticking a small dot in the middle
of my mirror, and trying to align it with the screws. If that's not a
good way to do it then I'll have to buy one of those laser
collimators. But I'm also thinking about just getting one of the 8"
dobs. Thanks for your suggestions.

Your collimation approach is error prone. And while laser collimators
generally work very well for Newtonians, they can also provide less than
perfect results, particularly when you are pushing magnification to its
limits, as is often the case with planetary viewing. For best results,
you should learn how to finish (or test) your collimation on a star.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

On 2007-05-02 18:14:39 -0400, Chris L Peterson said:

On Wed, 02 May 2007 21:44:52 GMT, Chris L Peterson
wrote:

An 8" scope (try Orion's offerings) will significantly outperform your
4" scope, but the requirement for good collimation remains.

I'll also add that you shouldn't overlook the value of tracking in your
current scope. I'm usually frustrated using a Dob for high power
observing of the Moon and planets, because the object drifts so quickly
out of the field. It can be hard just to simply observe.

_

And remember, seeing conditions play an IMPORtANT part too.

On May 2, 7:30 pm, Phoon Hencman wrote:
On 2007-05-02 18:14:39 -0400, Chris L Peterson said:

And remember, seeing conditions play an IMPORtANT part too.

During the 2005 opposition there were several large dust storms
on Mars and its atmosphere was too dustydirty to allow albedo
features to be resolved sharply.

I did 150 drawings of it for the "Grand Opposition of 2003" but
on the last one I didn't even get out my sketchpad.

Ben

On Wed, 02 May 2007, Bullseye wrote:

I have a Nexstar 114GT and it can give visuals of the moon nicely
(most scopes can I think) but I can't see sqwat when I point to Mars.
I pointed to it 1-2 years ago when it was all over the news that it
was close to Earth, but all I could see was a pink little ball, no
features at all. Also in Saturn all I could see is a tiny little dot
with a tiny circle around it.

What magnification(s) did you use?

How many times have you tried to observe each planet?

What was your average amount of eyepiece time per planetary session?

How was the seeing? (steady image, boiling image, something in
between, etc?

If you own fewer than five eyepieces, which eyepieces do you have
(design and focal length)?

What's the focal length of your telescope?

Did you attempt to sketch what you saw?

Did you check the scope's collimation prior to *each* observing
session?

Most planetary detail tends to be of much lower contrast than much
that's encountered in lunar observing. Not only must your telescope
be 'tweaked' to perfection; but you must also repeatedly (and rather
intensely) study a planet in order to develop 'an eye' for the details
specific to the given planet.

I've centered the scope and adjusted it
all the ways I'm supposed to to get the best image (I've forgotten the
exact terms that are used since I've ditched astronomy for awhile),
but trust me I did.

I also read your 2nd posting in this thread. You might benefit from
checking some on-line references on collimation. It may be necessary
for you to make adjustments to *both* mirrors -- not just the primary
mirror. A good on-line reference to start with is he
http://home.earthlink.net/~8-h-haggi.../beginners.htm

From the above site there are many worthy links, including one for
collimation. It may prove helpful to do a web-search and study
several different sources on collimation. Collimation is important
enough to gain a *thorough* understanding of.

I just want to sell this sucker and get a new one.
Can anyone recommend the best 4 inch reflectors out there for less
than $500? Or maybe a very good 8 inch dob for less than $500?

IMO it would be wise to master collimation *before* purchasing another
Newtonian. Otherwise you may find yourself in the same boat once
again. The alternative would be to go with a different type of
telescope for your next telescope.

Finally, most important of all: If at all possible find your nearest
astronomy club (or attend the nearest 'starparty') and share your
concerns with the people you meet there. It's *far* easier to resolve
situations such as yours in person, with your telescope on hand for
inspection.
--
Bill
Celestial Journeys
http://cejour.blogspot.com

I aline ALL of my scopes using a 35mm film can(plastic) and I'd lay odds
that with me doing sidewalk astronomy it's just as good as a laszer one
which I don't need/


The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
The Church of Eternity
http://home.inreach.com/starlord/church/Eternity.html
AD World
http://www.adworld.netfirms.com/


"Bullseye" wrote in message
...
On Wed, 2 May 2007 16:36:15 -0700, "Starlord"
wrote:

I would go for a single high power EP, they do much better that the
barlowed
ones do. I used my 4.8naggler EP during mars passing.


The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
The Church of Eternity
http://home.inreach.com/starlord/church/Eternity.html
AD World
http://www.adworld.netfirms.com/


wrote in message
roups.com...
On May 2, 5:21 pm, Bullseye wrote:
I have a Nexstar 114GT and it can give visuals of the moon nicely
(most scopes can I think) but I can't see sqwat when I point to Mars.
I pointed to it 1-2 years ago when it was all over the news that it
was close to Earth, but all I could see was a pink little ball, no
features at all. Also in Saturn all I could see is a tiny little dot
with a tiny circle around it. I've centered the scope and adjusted it
all the ways I'm supposed to to get the best image (I've forgotten the
exact terms that are used since I've ditched astronomy for awhile),
but trust me I did. I just want to sell this sucker and get a new one.
Can anyone recommend the best 4 inch reflectors out there for less
than $500? Or maybe a very good 8 inch dob for less than $500?

Mars will be almost overhead for north temperate latitudes this
December, although less than 16 arc-sec in diameter, so get yourself a
bigger telescope ASAP. For $500 you should be able to get an 8-inch
Dob AND a good 3x Barlow (you will probably need one.) If you can
stretch the budget a couple of hundred dollars go for a 10-inch, but
don't delay your purchase too long. Make sure you have about 30x to
35x per inch of aperture.

Practice observing Jupiter and Saturn, so that you will be ready for
Mars.


That's the term I meant to use, "collimated". I had forgotten it
because it's been a long while. I tried collimating it the cheap way.
Taking one of those small black containers that hold a roll of film,
making a small hole in the middle. Sticking a small dot in the middle
of my mirror, and trying to align it with the screws. If that's not a
good way to do it then I'll have to buy one of those laser
collimators. But I'm also thinking about just getting one of the 8"
dobs. Thanks for your suggestions.

I have a Nexstar 114GT and it can give visuals of the moon nicely
(most scopes can I think) but I can't see sqwat when I point to Mars.
I pointed to it 1-2 years ago when it was all over the news that it
was close to Earth, but all I could see was a pink little ball, no
features at all. Also in Saturn all I could see is a tiny little dot
with a tiny circle around it.

The others have made good suggestions -- making sure your scope is
collimated and even getting a bigger scope -- but keep in mind that Mars is
always a very challenging object. Many observers express disappointment.
Worse, right now Mars is only about 5 arc seconds in diameter. No scope, no
matter the aperture or optical quality, is going to show much. In December,
when it gets up to almost 16 arc seconds, it'll be better. But even then,
don't expect much. If you can see a polar cap and Syrtis Major during the
December opposition, then you should feel fortunate. It'll be 2018 before
we have a decent opposition again. As for Saturn, when I show it to the
public in good "seeing," I get one of two reactions: (1) "That looks like a
picture!" or (2) "It's so small!" Saturn *is* small. In addition, the
three planets that offer any hope of seeing detail (Mars, Jupiter, Saturn)
are much paler than juiced up HST photos suggest. You might experiment with
eyepiece filters (red or orange for Mars) to enhance contrast, but don't
expect to see much on Mars right now.
--
Curtis Croulet
Temecula, California
33°27'59"N, 117°05'53"W

"Bullseye" wrote in message
...
I have a Nexstar 114GT and it can give visuals of the moon nicely
(most scopes can I think) but I can't see sqwat when I point to Mars.
I pointed to it 1-2 years ago when it was all over the news that it
was close to Earth, but all I could see was a pink little ball, no
features at all. Also in Saturn all I could see is a tiny little dot
with a tiny circle around it. I've centered the scope and adjusted it
all the ways I'm supposed to to get the best image (I've forgotten the
exact terms that are used since I've ditched astronomy for awhile),
but trust me I did. I just want to sell this sucker and get a new one.
Can anyone recommend the best 4 inch reflectors out there for less
than $500? Or maybe a very good 8 inch dob for less than $500?

First, let's deal with Mars.

Don't know where you are, but, here in East Tennessee, Mars is rising around
0430 and the sun shows up around 0530. Thus, for the hour before Mars is
wiped out by the rising sun, the planet is low on the horizon. Objects that
are low on the horizon generally are not good targets if you are looking for
detail -- because -- the lower on the horizon, the more atmosphere you are
looking through, thus, the more degraded are seeing conditions. You really
need to wait a few months when Mars is higher in the sky at night.

Now, as for an 8-inch Dob. You can't go wrong with the Orion XT-8. I owned
one until Hurricane Katrina swept it away and I was delighted with it. In
2003, when Mars made its historically close approach to Earth, I saw the
polar ice caps and the dark markings on Mars with no difficulty, viewing
from a light-polluted urban location.

Check out the Orion website for the XT-8. You will find a basic XT-8 (the
"classic") and the Intelliscope version. The Intelliscope version adds over
$100 to the basic price PLUS you then buy the Intelliscope controller for
another $100 or so. You can get the Intelliscope version without the
handheld computer-- the Intelliscope version has the encoders built into the
base -- it works just like a normal Dob -- you can add the handheld computer
later to the Intelliscope version but, if you buy the basic
(non-Intelliscope version), you can't add Intelliscope later.

Here are the Orion Dobs -- note that the "classic" XT-8 is now $369.95 and
the XT-10 is $549.95.
http://www.telescope.com/jump.jsp?it...EGORY&itemID=9
At that rate, if you stay with the "classic" without the Intelliscope, you
could afford to go to the 10-incher. If you go with the Intelliscope model,
the XT-8 fits your $500.00 budget.

Here is a description of my XT-12
http://www.schlatter.org/Dad/Astronomy/XT%2012.htm
and the Intelliscope
http://www.schlatter.org/Dad/Astrono...ope%20page.htm

The XT-series (4.5, 6, 8, 10, and 12) are the same scopes, just different
aperture and different physical size and weight. You can pick up and carry
the 4.5, and 6 easily; the 8 is a handful but can be carried; if you're
young and in good shape you can carry the 10; don't even think about
carrying the 12.

A follow-up:

In situations such as this there are a multitude of possibilities,
only some of which have been addressed. Similarly, some of the
possibilities mentioned may not be relevant to the difficulties at
hand. None of us are all-knowing. None of us are able to study the
planetary images formed by your telescope. We don't mean to insult
your experience, intelligence, etc. when we offer suggestions. Yet,
sometimes I feel that my words (as well as those of others) may appear
to be somewhat condescending when they are not meant to be.

So, without making any assumptions I offer a list of possibilities in
no particular order:

poor seeing conditions
inadequately collimated optics
poor optical quality (telescope and/or eyepieces)
observer inexperience
insufficient magnification
thermal effects inside the telescope
thermal effects near the telescope

Other possibilities exist; but in my opinion (which is not always
correct) the difficulty is likely due to one or more of the
possibilities listed above. A knowledgeable amateur in your area, if
one could be found, would be able to pin down the problem and perhaps
even provide a remedy.

I would suggest not purchasing a new telescope until the cause of your
current difficulty has been determined or until you've seen and looked
through a telescope that you know you would enjoy owning.

Meanwhile, don't give up on your current telescope. Use it at every
reasonable opportunity. Your telescope is *far* superior to the best
telescope that Galileo used! It's capable of showing you *much* more
than what can be seen with your eyes alone.

Concentrate more on what you can see and less on what you can't see.
Photographs, CCD images and sketches often enhance the contrast and
color (when present) of planetary features. Colors tend to be very
subtle when present. Contrast likewise tends to be very subtle --
like the shadings on a small section of egg shell.
--
Bill

On Thu, 3 May 2007 04:21:03 -0400, "Joe S." wrote:


"Bullseye" wrote in message
.. .
I have a Nexstar 114GT and it can give visuals of the moon nicely
(most scopes can I think) but I can't see sqwat when I point to Mars.
I pointed to it 1-2 years ago when it was all over the news that it
was close to Earth, but all I could see was a pink little ball, no
features at all. Also in Saturn all I could see is a tiny little dot
with a tiny circle around it. I've centered the scope and adjusted it
all the ways I'm supposed to to get the best image (I've forgotten the
exact terms that are used since I've ditched astronomy for awhile),
but trust me I did. I just want to sell this sucker and get a new one.
Can anyone recommend the best 4 inch reflectors out there for less
than $500? Or maybe a very good 8 inch dob for less than $500?

First, let's deal with Mars.

Don't know where you are, but, here in East Tennessee, Mars is rising around
0430 and the sun shows up around 0530. Thus, for the hour before Mars is
wiped out by the rising sun, the planet is low on the horizon. Objects that
are low on the horizon generally are not good targets if you are looking for
detail -- because -- the lower on the horizon, the more atmosphere you are
looking through, thus, the more degraded are seeing conditions. You really
need to wait a few months when Mars is higher in the sky at night.

Now, as for an 8-inch Dob. You can't go wrong with the Orion XT-8. I owned
one until Hurricane Katrina swept it away and I was delighted with it. In
2003, when Mars made its historically close approach to Earth, I saw the
polar ice caps and the dark markings on Mars with no difficulty, viewing
from a light-polluted urban location.

Check out the Orion website for the XT-8. You will find a basic XT-8 (the
"classic") and the Intelliscope version. The Intelliscope version adds over
$100 to the basic price PLUS you then buy the Intelliscope controller for
another $100 or so. You can get the Intelliscope version without the
handheld computer-- the Intelliscope version has the encoders built into the
base -- it works just like a normal Dob -- you can add the handheld computer
later to the Intelliscope version but, if you buy the basic
(non-Intelliscope version), you can't add Intelliscope later.

Here are the Orion Dobs -- note that the "classic" XT-8 is now $369.95 and
the XT-10 is $549.95.
http://www.telescope.com/jump.jsp?it...EGORY&itemID=9
At that rate, if you stay with the "classic" without the Intelliscope, you
could afford to go to the 10-incher. If you go with the Intelliscope model,
the XT-8 fits your $500.00 budget.

Here is a description of my XT-12
http://www.schlatter.org/Dad/Astronomy/XT%2012.htm
and the Intelliscope
http://www.schlatter.org/Dad/Astrono...ope%20page.htm

The XT-series (4.5, 6, 8, 10, and 12) are the same scopes, just different
aperture and different physical size and weight. You can pick up and carry
the 4.5, and 6 easily; the 8 is a handful but can be carried; if you're
young and in good shape you can carry the 10; don't even think about
carrying the 12.


Sorry about your scope getting swept away. When Mars does show up
higher in the sky in a few months what will we be able to see? You say
in the 2003 opposition you were able to see the polar caps and dark
markings. When it's not so close to Earth what do people usually see
in 4-8 inch scopes? I hope it's not just an orange ball