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Richard,

Interesting thoughts. Thanks for the input.

BTW I'm using an Starlight Xpress Mx7-c with my fastar lens. Most of the starlight cameras should work with their adapter. They're smaller and lighter than the ST-237 so that shouldn't be an issue.

Scott

--- In C14@y..., Scott Evans <sevans@i...> wrote:

Richard,

Your comments are interesting because I had always heard that the

focal

ratio would be the primary factor in determining exposure time

regardless

of focal length. Shouldn't the f/5 fsq be a shorter exposure than

the f/11

c-14?

BTW with the fastar lens installed I have an 735mm focal length 14"

scope. ;-)

Scott

First of all, I am talking specifically about CCD imaging.

The effective focal length of the telescope coupled with the physical
size of your ccd chip's imaging area (when used in the "normal" way,
ie prime focus) determine the field of view of the imager. I say
effective focal length to take into account the possible use of a
focal length reducer or extender.

This is independent of focal ratio.

In the case of the C14, it has a very long focal length and therefore
cannot provide me the wide field of view that I can get from the FSQ.
On the other hand, because it is 14" in diameter, it gathers 1225%
more light than does a 4" scope. So if somehow you could give the two
scopes the same FOCAL LENGTH, therefore getting exactly the same
field of view in either scope, you'd find the C14 to be a LOT FASTER
to expose.

What I was noting as I was beginning my quest into widefield imaging
is how much longer the exposures take, simply because the only way I
have to get a short focal length is from a small aperture telescope
and they sure don't gather light as quickly as that C14 does.....

I understand the attraction of the FASTAR adaptor now, for widefield
work. Too bad that it is not recommended for any of the popular high
resolution cameras such as the SBIG 8 and 10 series and the FLI
Maxcam and Dream Machine series or the Starlight Express HX and MX
series. All the cameras weigh too much and offer too much of an
increase in the central obstruction.

So you can get and ST237 CCD camera and FASTAR and shoot at lower
resolution fast or you can use a newer generation camera and shoot
higher resolution slowly in a refractor. Funny thing is that other
than download time, there's nothing about high resolution from an
image capture perspective that is any slower than low resolution. But
because the mechanical designs of the cameras are so big and heavy,
the interesting cameras cannot be used with the most interesting
telescope configuration option that Celestron sells for the C14.

--- In C14@y..., Scott Evans <sevans@i...> wrote:

Richard,

Your comments are interesting because I had always heard that the

focal

ratio would be the primary factor in determining exposure time

regardless

of focal length. Shouldn't the f/5 fsq be a shorter exposure than

the f/11

c-14?

BTW with the fastar lens installed I have an 735mm focal length 14"

scope. ;-)

Scott

First of all, I am talking specifically about CCD imaging.

The effective focal length of the telescope coupled with the physical
size of your ccd chip's imaging area (when used in the "normal" way,
ie prime focus) determine the field of view of the imager. I say
effective focal length to take into account the possible use of a
focal length reducer or extender.

This is independent of focal ratio.

In the case of the C14, it has a very long focal length and therefore
cannot provide me the wide field of view that I can get from the FSQ.
On the other hand, because it is 14" in diameter, it gathers 1225%
more light than does a 4" scope. So if somehow you could give the two
scopes the same FOCAL LENGTH, therefore getting exactly the same
field of view in either scope, you'd find the C14 to be a LOT FASTER
to expose.

What I was noting as I was beginning my quest into widefield imaging
is how much longer the exposures take, simply because the only way I
have to get a short focal length is from a small aperture telescope
and they sure don't gather light as quickly as that C14 does.....

I understand the attraction of the FASTAR adaptor now, for widefield
work. Too bad that it is not recommended for any of the popular high
resolution cameras such as the SBIG 8 and 10 series and the FLI
Maxcam and Dream Machine series or the Starlight Express HX and MX
series. All the cameras weigh too much and offer too much of an
increase in the central obstruction.

So you can get and ST237 CCD camera and FASTAR and shoot at lower
resolution fast or you can use a newer generation camera and shoot
higher resolution slowly in a refractor. Funny thing is that other
than download time, there's nothing about high resolution from an
image capture perspective that is any slower than low resolution. But
because the mechanical designs of the cameras are so big and heavy,
the interesting cameras cannot be used with the most interesting
telescope configuration option that Celestron sells for the C14.

--- In C14@y..., Scott Evans <sevans@i...> wrote:

Richard,

Your comments are interesting because I had always heard that the

focal

ratio would be the primary factor in determining exposure time

regardless

of focal length. Shouldn't the f/5 fsq be a shorter exposure than

the f/11

c-14?

BTW with the fastar lens installed I have an 735mm focal length 14"

scope. ;-)

Scott

The faster f-ratio equals shorter exposure principle only applies to
extended objects. For stars that are essentially point sources,
exposur time depends on the number of photons collected in a given
time, i.e. the actual aperture, not the aperture ratio.
Hope this helps
Robert Bilsborrow

Hi C14-lovers,

Yesterday someone from Germany offered me an old C14 manufactured
in the early 80's.
I asked him if it has Starbright Coatings and he told me that there
is no such label on the tube.

My question now is: how much procent of light will I loose if this
C14 has not the Starbright Coatings: 10, 20 maybe even 30 procent ?

If it is that much I will not gain too much if compared with my
excellent C11 which has the Starbright Coatings.

Several years ago Celestron announced that the schmidt corrector
plates were now made from crown glass (BK-7 ?) instead of just
(green) plate glass (at least on their C8's).
I know that Meade uses plate glass (very greenish ! and so much lesser
light transmission) on their 8 and 10 inch models but BK-7 on the
12 inch SCT.
So what kind of glass type the C14 corrector plate is made of
nowadays and when did Celestron started to use crown glass ?

Thanks very much for any info concerning the mirror coatings and
corrector plate glass used.

Rgds,
Marc Biesmans, Belgium

Richard,

Your comments are interesting because I had always heard that the focal ratio would be the primary factor in determining exposure time regardless of focal length. Shouldn't the f/5 fsq be a shorter exposure than the f/11 c-14?

BTW with the fastar lens installed I have an 735mm focal length 14" scope. ;-)

Scott

--- In C14@y..., boshar@t... wrote:

Hi all,

I have a 1989 non-ED 178mm AP Starfire.
I'd like to have a large aperture compact telescope and the C14

seems

to fit what I need. However, some tell me the quality has suffered

in

recent years. Can someone tell me of their experiences in comparing
these two very different telescopes?

I have a cm1400 and am quite happy with it.

Would I lose much planetery detail and the ability to split close

No. You will get fine detail of the planets as long as the seeing
conditions are good.

doubles? Are stars fuzzy or pinpointed when using the C14 visualy?

Stars look great. Collimate the scope though!

I

would presume ccd deep sky imaging would improve with the C14 but,
would the stars be bloated?
My skies are 4-5 magnitude and the Milky Way is easily seen almost

to

the horizon.

The main thing to consider is the C14 is a very long focal length
(3910mm) scope and therefore your CCD images will be narrowfield not
widefield like with the AP. The next thing to consider is that for
any given target, the extra light gathering power of the C14 is nice.

I shot lots of images with my 14 and then recently started to do
widefield with a 4" refractor (TV101 and FSQ106). The biggest gripe I
have is the exposures take A LOT LONGER than what I'd have to do with
the C14. For example, a 5 to 10 minute exposure seems to take 40 to
60 minutes with the smaller refractors. It is a light gathering issue.

The f/3.3 focal reducers are really hard to make work with out
introducing a ton of COMA into the image, so about all I think you
can easily do from a focal reduction perspective is to use the f/6.3
reducers (gives an F7 with the 14").

You will notice that you see a very narrow field of view through the
14 and that the exposures are a lot faster.

I'd love to have a 14" scope with a 600-800mm focal length...


Here are links to somee images I took with mine:







The Star Queen is at both f/11 and at f/7 to show the difference in
focal length. The M57 is at f/11 and the M27 and bubble are at f/7
I use the Celestron focal reducer.
rdc

Thanks for any feedback from your experience.

Bob

I have a 1989 non-ED 178mm AP Starfire.

SNIP

However, some tell me the quality has suffered in
recent years.

Can't comment on that, but Celestron and Meade produce telescopes
that on average are good but this means that there are excellent ones
and less good ones as well. I guess since they make less C-14's than
C-8's quality control could be better for these instruments.

Can someone tell me of their experiences in comparing
these two very different telescopes?

Wish I could...

Would I lose much planetery detail and the ability to split close
doubles?

Under perfect seeiing the C-14 would show more (more light, more
detail due to larger aperture)and should be able to split closer
doubles. Problem is that larger telescopes and telescopes with
obstruction suffer more from seeiing than refractors. Due to the
obstruction, you will also loose some contrast in the image!

Are stars fuzzy or pinpointed when using the C14 visually?

Pinpoint in my C-14, but make sure collimation is as good as you can
get it... same comments about seeiing: brighter stars at higher
magnification will look "fuzier" than in the Starfire due to
obstruction and larger aperture being more sensitive to seeiing
effects.

I would presume ccd deep sky imaging would improve with the C14

but,

would the stars be bloated?

Due to the long focal length (= higher primary magnification) and due
to the optical system used, brighter stars appear somewhat larger
than they would with a refractor.

My five cents...

Geert Vandenbulcke

Hi all,

I have a 1989 non-ED 178mm AP Starfire.
I'd like to have a large aperture compact telescope and the C14 seems
to fit what I need. However, some tell me the quality has suffered in
recent years. Can someone tell me of their experiences in comparing
these two very different telescopes?
Would I lose much planetery detail and the ability to split close
doubles? Are stars fuzzy or pinpointed when using the C14 visualy? I
would presume ccd deep sky imaging would improve with the C14 but,
would the stars be bloated?
My skies are 4-5 magnitude and the Milky Way is easily seen almost to
the horizon.

Thanks for any feedback from your experience.

Bob

--- In C14@y..., "Jim Anderson" <jim.a@h...> wrote:

If I may suggest the Williams Optics GT-ONE HD mount.

Substantially less

money than the 1200 but rated perfectly for what you want to do and

more. I

have had mine now for about 4 months and I can do nothing but rave

about it.

Check out the Yahoo GT-ONE and Williams Optics groups. You won't be
disappointed.

Jim

One of my local friends in the SF Bay area has one of those GT-One
mounts that he bought second-hand from another observer here. He has
had a nightmare trying to get it to work correctly. It had problems
with the motors: the shafts had excessive play in them, there was as
stripped out hole that retains one of the tensioning screws into the
mount. And the control electronics had problems as well. The guy that
dumped it on my friend claimed the mount was nearly new and had "only
been used once or twice, and not for imaging" but if so, that said
the mount was defective from the get-go. The long and short of it is
that William Yang has offered to fix it, but my friend has to ship it
back to Taiwan to get it repaired.

I think it is great that William stands behind his product, but
really makes me angry to hear of someone selling a bad mount or maybe
the mount was defective from the start, which makes me wonder about
William Optics consistency. It is too early to tell what the real
problem was, but it certainly has cost my friend a lot of time and
aggravation.

In hearing reports from owners of the GT-One, it sounds like the
mount is a good one if it works OK, but I've not heard of too many
folks that have them right now so my sample size is sort of small.
rdc

If I may suggest the Williams Optics GT-ONE HD mount. Substantially less
money than the 1200 but rated perfectly for what you want to do and more. I
have had mine now for about 4 months and I can do nothing but rave about it.
Check out the Yahoo GT-ONE and Williams Optics groups. You won't be
disappointed.

Jim

--- In C14@y..., sand27921@y... wrote:

has anyone found a way to modify the c14 to be able to use the key
pad of a go to electronic scope? Celestron says that it does not
have it available. Maby if enough c14 users asked they would make

the

modifications available. Any comments?

Your wish is Celestron's command: check the Celestron ad in the
December 2001 S&T (Page 43) "Introducing The New Celestron 14" GOTO
Telescope".

They base the mount on the CI700, and add "Nextar GOTO features".

I wonder if they made any improvements to the CI700 when they added
the GOTO features?
rdc

has anyone found a way to modify the c14 to be able to use the key
pad of a go to electronic scope? Celestron says that it does not
have it available. Maby if enough c14 users asked they would make the
modifications available. Any comments?

C14@... wrote:

Date: Tue, 20 Nov 2001 23:16:38 -0000
From: golubosks001@...
Subject: CI-700 Mount

The C-14 is my dream scope. I may have the opportunity to get a fork
mounted one in March for a really good price. But, if that falls
through, I will get a new one on an EQ mount probably around
Christmas 02.

My concern it the CI-700 mount. I've considered the Astrophysics 900
GOTO. But, will not be able to afford it. So, I am considering the
G-11 (with Gemini GOTO) or the CI-700 (GOTO).

I've done my research and have learned a lot about the G-11. But,
finding information on the CI-700 is hard. I've only found one web
page that talks about the mount with a C-14 attached.

If the mounts are similar, other than the eye appeal of a G-11, is
the extra expense worth the price of the G-11 over the CI-700?

I would like for anyone who has used both mounts and perferably has
considerable experience with the Celestron mount to answer.

I plan on using the scope for mostly visual purposes. I will take
snap shots of the moon, sun, and planets through the scope. I may do
some piggy back (manual guided)in a sheltered location for for
exposures of 10 minutes but, will never get into CCD or really long
exposure photography.

Is it worth buying the scope on the CI-700 mount and waiting until I
can afford the Astrophysics 900?

I have owned a CI700 and sold it. Here are my main gripes with the CI700:
the RA clutch slips terribly. If you tighten the front plate setscrews, you
can keep it from totally slipping all the time, but then it won't freewheel
when you loosen the clutch. I hate that.

Celestron takes a really cavalier attitude about it too: they just declare
that it works the way it was designed and that is the way it is. They further
claim that it is best to work that way. BS I say.

My friend Jim Nomura (jnomura@...) has done a lot of development work
to straighten out the CI700 problems and he can do a re-work for you for a
few hundred dollars. He has also adapted the Sky Sensor 2000 GOTO system from
Vixen to work with the mount. You may want to consider that.

As it stands the CI700 is way too lightweight for the C14. If you re-do it
then it can work, but it is still a very frustrating experience to me. Maybe
it is fine with the C11, but for imaging with the 14 it is pretty unusable
from my perspective.

I'd buy the OTA only and find a decent mount. The AP mounts are great but
expensive and hard to find. The Vixen and Losmandy mounts are pretty good,
but anything lighter than a G11 is too light. Personally I would recommend
finding a used HGM200 or HGM100 mount if you can, as you can do imaging with
it very well in case the fancy strikes you.

The C-14 is my dream scope. I may have the opportunity to get a fork
mounted one in March for a really good price. But, if that falls
through, I will get a new one on an EQ mount probably around
Christmas 02.

My concern it the CI-700 mount. I've considered the Astrophysics 900
GOTO. But, will not be able to afford it. So, I am considering the
G-11 (with Gemini GOTO) or the CI-700 (GOTO).

I've done my research and have learned a lot about the G-11. But,
finding information on the CI-700 is hard. I've only found one web
page that talks about the mount with a C-14 attached.

If the mounts are similar, other than the eye appeal of a G-11, is
the extra expense worth the price of the G-11 over the CI-700?

I would like for anyone who has used both mounts and perferably has
considerable experience with the Celestron mount to answer.

I plan on using the scope for mostly visual purposes. I will take
snap shots of the moon, sun, and planets through the scope. I may do
some piggy back (manual guided)in a sheltered location for for
exposures of 10 minutes but, will never get into CCD or really long
exposure photography.

Is it worth buying the scope on the CI-700 mount and waiting until I
can afford the Astrophysics 900?

Thanks
Ron

--- In C14@y..., kberna1376@a... wrote:

Beautiful shot! I have a AP1200GTO scheduled for delivery in

January

because of my frustration with trying to do CCD with the C14-G11
combo. Hope I have as much sucess as you have...Ken

Thanks for the comment on the shot. I think you will have equally
good or better shots once you get that prized AP1200GTO.

That mount is fantastic. I just love it. I finally have a platform
that I can mount nearly anything. Lately I have been running a pair
of refractors in tandem: an FSQ106 for imaging and a TV101 as the
finderscope. You will really enjoy your mount.

--- In C14@y..., rdcrisp@e... wrote:

--- In C14@y..., kberna1376@a... wrote:

I have used the C14-G11 combo for a couple of years. The G11

with

the C14 is very good visually, and very portable, but is

difficult

for CCD work. I have had some good resuts with it in Fastar mode

at

f2.1. It is also OK using a 3.3 reducer. But even then you need
very still wind conditions. I have not had good results at

longer

focal lengths. Also, I have heard comments that the stepper

motors

introduce minute vibrations that reduce CCD resolution.

Ken

I have a CM1400 and use it for CCD work with the ST7E camera. I
originally used it with the CI700 mount that was part of the

original

sales package. I was always disappointed with the results. I
understand the CI700 is similiar to the G11, but perhaps not as

good.

I finally lucked out and found an AP1200GTO mount and life has been
wonderful since.

Here is a CCD benchmark between the CI700 and the AP1200:

CI700 picture:

ebula+17March+2001.jpg&.src=ph&.view=t&.hires=t

AP1200GTO picture:

ebula+30May2001.jpg&.src=ph&.view=t&.hires=t


Both images were made using the CM1400 and the ST7E running at the
F/11 focal ratio. The CI700 shot had minimal mass in the system,
while the AP1200GTO shot had a TV101 piggybacked atop the CM1400.

The mount made all the difference in the world. The CI700 shot was
the best I ever got with it. I sold it to a visual-only fellow that
is quite happy with it.
rdc

Beautiful shot! I have a AP1200GTO scheduled for delivery in January
because of my frustration with trying to do CCD with the C14-G11
combo. Hope I have as much sucess as you have...Ken

--- In C14@y..., kberna1376@a... wrote:

I have used the C14-G11 combo for a couple of years. The G11 with
the C14 is very good visually, and very portable, but is difficult
for CCD work. I have had some good resuts with it in Fastar mode

at

f2.1. It is also OK using a 3.3 reducer. But even then you need
very still wind conditions. I have not had good results at longer
focal lengths. Also, I have heard comments that the stepper motors
introduce minute vibrations that reduce CCD resolution.

Ken

I have a CM1400 and use it for CCD work with the ST7E camera. I
originally used it with the CI700 mount that was part of the original
sales package. I was always disappointed with the results. I
understand the CI700 is similiar to the G11, but perhaps not as good.
I finally lucked out and found an AP1200GTO mount and life has been
wonderful since.

Here is a CCD benchmark between the CI700 and the AP1200:

CI700 picture:


ebula+17March+2001.jpg&.src=ph&.view=t&.hires=t

AP1200GTO picture:


ebula+30May2001.jpg&.src=ph&.view=t&.hires=t


Both images were made using the CM1400 and the ST7E running at the
F/11 focal ratio. The CI700 shot had minimal mass in the system,
while the AP1200GTO shot had a TV101 piggybacked atop the CM1400.

The mount made all the difference in the world. The CI700 shot was
the best I ever got with it. I sold it to a visual-only fellow that
is quite happy with it.
rdc

to anyone. The program will not accept my e-mail which is
ctsm27@... I wish to enquire if anyone has found the new goto
controls. I think that someone should be able to retrofit the key pad
to c14 that already has the drive motors. Those of us that have the
old c14 with the fork mount would like to be able to have the goto
features. If anyone has any information i would appreciate.
Clarence Sanders

TEST