Re: Mounting a Guide Scope to a G11 Mount
Putting the guide scope side-by-side with a fairly short focal length imaging scope is fine, but if you¡¯re going to use the C9.25 for imaging it¡¯s best to piggyback the guide scope. ?Guide scopes can be surprisingly small, so a good solution would be to piggyback the guider on the C9.25. ?Unless you¡¯re pushing to the total weight limit, that should work pretty well.
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On Dec 14, 2020, at 9:56 AM, Terry Pullen via <tpullen152@...> wrote:
?Hello Group
Having just refined and improved my Polar Alignment, of my permanent pier mount G11 using Sharp Cap, I am now keen to get into guided imaging.
I did the PA adjustment using my DSLR camera connected to one of my side-by-side main scopes, a Sky 90. The other scope on the mount saddle is a C 9.25.
My thinking is to remove the C9.25 from the saddle then add a new guide scope [make/size/FL yet to be selected] to replace the C9.25 and then reposition and rebalance this new Sky90/Guide Scope combo.
My question concerns the Guide Scope - is mounting the GS onto the side by side saddle, rather than on top of the Sky90, an acceptable arrangement?
I anticipate the distance between the centre axis of the imaging and guiding scopes to be around 7". I presume I would need to aim the Guide Camera to match the Sky90's target/FOV.
If anyone would like to also recommend a Guide Scope for use with a ZWO ASI120MM MINI Guide Camera then I shall be very pleased to see these. ??
Many Thanks
Terry [uk] ????
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Re: Mounting a Guide Scope to a G11 Mount
Paul, With good sky, and good focus, I get stars hfd bouncing around from high 2 to 5.?? Guiding is still good with 3? - 4. Mearl
On Mon, Dec 14, 2020, 1:42 PM Paul Goelz < pgoelz@...> wrote: On 12/14/2020 1:26 PM, Mearl Balmer wrote:
> I like my Orion 9X60 guide scope with its focus control. Pairs with my
> ASI290mm well.
>
> Mearl
Mearl,
I have the Agena version of that same scope and also the ASI290.? I have
never been happy with the size of the stars.? Initially they looked
awful.? Adding a UV/IR filter helped some and adding a minus-violet
filter helped more.? But the HFD never is less than maybe 4+ no matter
how carefully I focus.? In places they show very noticeable coma.
Agena thinks the issue might be the objective and they are kindly
sending a replacement scope which I have not received yet.? But since
you have the same setup.....how do your stars look?? What is a typical
HFD?
I have always wondered what to expect on an inexpensive scope but Agena
could not tell me what a reasonable HFD would be even though this is a
pretty common setup and the scope is supposed to be a guide scope.
Paul
--
Paul Goelz
Rochester Hills, MI? USA
pgoelz@...
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On 12/14/2020 1:33 PM, Brian Valente wrote: i understand you are doing guiding without PE correction. But you are asking questions?related to the periodic errors. i.e., you are looking at periodic error through the lens of guiding. I can only say this so many times: it's not effective and masks issues I think we are talking past each other here. I completely understand what you are saying. I only continue this line of inquiry because as far as I know, while guiding may mask PE issues it does not CREATE periodic error.... correct? So the periodic error I see in a guide log at the bearing frequency of 76s is real and only the relative magnitude is questionable, right? So my question remains..... the PHD2 frequency analysis of a GUIDED session shows an 0.8" residual error at the bearing frequency of 76s. I assume that represents the remaining RMS amplitude of the guide star error after guiding corrections have been applied? If so, I am not all that concerned because that is better than my typical seeing. It may be (and probably is) worse uncorrected but for now I am interested in understanding and evaluating the CORRECTED performance since that is what ends up in my images. In the absence of stars, all I can do at present is work with what I have, which are about ten guided sessions. I'd love to do a 30 minute unguided session but that does not look likely for many days. I'm ready to just drop this and forge ahead alone, but seeking input from those who understand this more than I currently do seemed logical? I think I am asking rational questions? Paul -- Paul Goelz Rochester Hills, MI USA pgoelz@... www.pgoelz.com
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Re: Mounting a Guide Scope to a G11 Mount
On 12/14/2020 1:26 PM, Mearl Balmer wrote: I like my Orion 9X60 guide scope with its focus control. Pairs with my ASI290mm well.
Mearl Mearl, I have the Agena version of that same scope and also the ASI290. I have never been happy with the size of the stars. Initially they looked awful. Adding a UV/IR filter helped some and adding a minus-violet filter helped more. But the HFD never is less than maybe 4+ no matter how carefully I focus. In places they show very noticeable coma. Agena thinks the issue might be the objective and they are kindly sending a replacement scope which I have not received yet. But since you have the same setup.....how do your stars look? What is a typical HFD? I have always wondered what to expect on an inexpensive scope but Agena could not tell me what a reasonable HFD would be even though this is a pretty common setup and the scope is supposed to be a guide scope. Paul -- Paul Goelz Rochester Hills, MI USA pgoelz@... www.pgoelz.com
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Hi Paul
i understand you are doing guiding without PE correction. But you are asking questions?related to the periodic errors. i.e., you are looking at periodic error through the lens of guiding. I can only say this so many times: it's not effective and masks issues
If you want to discuss your guiding results in general and guiding parameters, that's a different story, but your questions continue to be around how PE is being handled.
On Mon, Dec 14, 2020 at 9:08 AM Paul Goelz < pgoelz@...> wrote: On 12/14/2020 11:38 AM, Brian Valente wrote:
> My (strong) suggestion is that you work on PEC completely separately
> from guiding. Use PEMPro and PEMPro log viewer to test and evaluate your
> PEC completely standalone.
>
> Guiding and the settings there can cloud the specifics.
As I have stated many times before, PEC WAS NOT ENABLED for most if not
all of the old logs that I examined just now and for only a small
portion of the log you saw.? I agree that in the log you saw, PEC while
it was on eliminated the worm and worm/2 signals and accentuated the 76s
signal.... and I understand why.? I have trained PEC several times,
found that it did not help and so I turned it off and left it off.? And
the several times I looked to verify it was off.... it was off.? So PEC
is NOT a factor in the other logs I examined this morning where the 76s
signal was predominant.
> There is never a case without PEC where a 7.5x fundamental is higher
> than the primary PE. You might be seeing post-guiding results where the
> PE is corrected?
Yes, I am of course seeing post-guiding results since as I said, these
logs were from imaging sessions where guiding was enabled.? But I would
expect that guiding would be just about as effective on a 76s signal as
it would be on a 240s signal given my 2s guiding exposures?? The fact
remains that in almost all of my guide logs MADE WITH PEC OFF, the 76s
signal was at least 50% higher than any other signal.? ???
As soon as I can see stars again I'll do an unguided log but for now
this is what I have to work with.? I am not unhappy with my guiding
results so far..... PHD says my peak error is always less than 2" and
usually around 1".? I started looking more closely a couple days ago
when I had a session where the peak was noticeably higher in what
appeared to be fairly stable seeing.? That was my first serious session
with multi star guiding a well as polar alignment using a Polemaster.? I
would have expected both to improve things and they certainly would not
be expected to cause the larger RA swings I observed?
Paul
--
Paul Goelz
Rochester Hills, MI? USA
pgoelz@...
-- Brian?
Brian Valente portfolio
|
Re: Mounting a Guide Scope to a G11 Mount
I like my Orion 9X60 guide scope with its focus control. Pairs with my ASI290mm well.
Mearl
On Mon, Dec 14, 2020, 12:56 PM Terry Pullen via <tpullen152= [email protected]> wrote: Hello Group
Having just refined and improved my Polar Alignment, of my permanent pier mount G11 using Sharp Cap, I am now keen to get into guided imaging.
I did the PA adjustment using my DSLR camera connected to one of my side-by-side main scopes, a Sky 90. The other scope on the mount saddle is a C 9.25.
My thinking is to remove the C9.25 from the saddle then add a new guide scope [make/size/FL yet to be selected] to replace the C9.25 and then reposition and rebalance this new Sky90/Guide Scope combo.
My question concerns the Guide Scope - is mounting the GS onto the side by side saddle, rather than on top of the Sky90, an acceptable arrangement?
I anticipate the distance between the centre axis of the imaging and guiding scopes to be around 7". I presume I would need to aim the Guide Camera to match the Sky90's target/FOV.
If anyone would like to also recommend a Guide Scope for use with a ZWO ASI120MM MINI Guide Camera then I shall be very pleased to see these. ??
Many Thanks
Terry [uk] ????
|
Mounting a Guide Scope to a G11 Mount
Hello Group
Having just refined and improved my Polar Alignment, of my permanent pier mount G11 using Sharp Cap, I am now keen to get into guided imaging.
I did the PA adjustment using my DSLR camera connected to one of my side-by-side main scopes, a Sky 90. The other scope on the mount saddle is a C 9.25.
My thinking is to remove the C9.25 from the saddle then add a new guide scope [make/size/FL yet to be selected] to replace the C9.25 and then reposition and rebalance this new Sky90/Guide Scope combo.
My question concerns the Guide Scope - is mounting the GS onto the side by side saddle, rather than on top of the Sky90, an acceptable arrangement?
I anticipate the distance between the centre axis of the imaging and guiding scopes to be around 7". I presume I would need to aim the Guide Camera to match the Sky90's target/FOV.
If anyone would like to also recommend a Guide Scope for use with a ZWO ASI120MM MINI Guide Camera then I shall be very pleased to see these. ??
Many Thanks
Terry [uk] ????
|
On 12/14/2020 11:38 AM, Brian Valente wrote: My (strong) suggestion is that you work on PEC completely separately from guiding. Use PEMPro and PEMPro log viewer to test and evaluate your PEC completely standalone.
Guiding and the settings there can cloud the specifics. As I have stated many times before, PEC WAS NOT ENABLED for most if not all of the old logs that I examined just now and for only a small portion of the log you saw. I agree that in the log you saw, PEC while it was on eliminated the worm and worm/2 signals and accentuated the 76s signal.... and I understand why. I have trained PEC several times, found that it did not help and so I turned it off and left it off. And the several times I looked to verify it was off.... it was off. So PEC is NOT a factor in the other logs I examined this morning where the 76s signal was predominant. There is never a case without PEC where a 7.5x fundamental is higher than the primary PE. You might be seeing post-guiding results where the PE is corrected? Yes, I am of course seeing post-guiding results since as I said, these logs were from imaging sessions where guiding was enabled. But I would expect that guiding would be just about as effective on a 76s signal as it would be on a 240s signal given my 2s guiding exposures? The fact remains that in almost all of my guide logs MADE WITH PEC OFF, the 76s signal was at least 50% higher than any other signal. ??? As soon as I can see stars again I'll do an unguided log but for now this is what I have to work with. I am not unhappy with my guiding results so far..... PHD says my peak error is always less than 2" and usually around 1". I started looking more closely a couple days ago when I had a session where the peak was noticeably higher in what appeared to be fairly stable seeing. That was my first serious session with multi star guiding a well as polar alignment using a Polemaster. I would have expected both to improve things and they certainly would not be expected to cause the larger RA swings I observed? Paul -- Paul Goelz Rochester Hills, MI USA pgoelz@... www.pgoelz.com
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Re: Losmandy Update: Covid
Sorry to hear Brian. Hope the team recovers quickly! Stay strong!
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I have a measurement request from any Titan owner who has access to their titan and can do a quick physical measurement for me??
can you please email me direct, thanks a million
brian at losmandy dot com -- Brian?
Brian Valente portfolio
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Hi Paul
>>>Note that all this analysis is on guide logs with guiding enabled.?
My (strong) suggestion is that you work on PEC completely separately from guiding. Use PEMPro and PEMPro log viewer to test and evaluate your PEC completely standalone.?
Guiding and the settings there can cloud the specifics.?
There is never a case without PEC where a 7.5x fundamental is higher than the primary PE. You might be seeing post-guiding results where the PE is corrected? Remember PHD analysis are at best estimates based on backing out the corrections. The only true way to look at this is unguided results, and preferably outside PHD?
On Mon, Dec 14, 2020 at 7:46 AM Paul Goelz < pgoelz@...> wrote: On 12/11/2020 11:46 PM, Brian Valente wrote:
> Hi Paul
>
> i agree DEC looks pretty?good. again the amount of backlash will change
> through the night, primarily due to changes in your scope orientation
> (i.e., altitude)
>
> RA seems to me to show issues related to a bad PEC. you have a lot of
> back-and-forth
OK, in the past couple days I have learned a lot about how to evaluate
my guide logs.? The following picture emerges after looking at ALL my
old logs (about ten of them) in the PHD2 log viewer.? PEC was off for
most if not all of these because I never found it to improve the
performance.? Now I know why.? Seeing was variable and mostly bad, but
that would only contribute noise to the frequency analysis, right?
1.? In all but one or two of my old logs, I see the worm and worm/2
signals but the predominant signal by far in the frequency domain is the
76.2s signal from the worm bearing(s).
2.? Because the 76.2s signal is not phase locked to the worm period, it
cannot be removed with PEC training and in fact will likely be magnified
by PEC because the G2 does not average multiple training runs (which
would average out the 76.2s signal and reduce or remove it from the
resulting corrections).
3.? If I am interpreting the log viewer correctly in the frequency
analysis, the corrected error at 76s is a maximum of about 0.8".? Since
that is the predominant signal and the corrected error of the other
signals is lower, is this enough error to worry about?? My seeing is
RARELY that good ;)
4.? Would it be reasonable to assume that the worm bearing signal should
never exceed the 240s worm signal and if so, is it time to do a simple
RA worm bearing and stop screw adjustment to see if it can be reduced?
Right now, the RA is untouched from as-received.
Note that all this analysis is on guide logs with guiding enabled.? I do
not have any unguided logs to analyze and according to the weather
forecast, I will not have an opportunity to make one for quite some time
:(
Paul
--
Paul Goelz
Rochester Hills, MI? USA
pgoelz@...
-- Brian?
Brian Valente portfolio
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Re: Losmandy Update: Covid
So sorry to hear about this Brian.
Please extend my condolences and prayers for a speedy recovery.
It appears we are going to be rife with this stuff.
One of our Daughters teaches nursing at USC. And she has become very concerned.
She told us to not even go to the grocery store.
--
SonnyE
(I suggest viewed in full screen)
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Re: Losmandy Update: Covid
So sorry to hear this, Brian.? Get well soon. All of you.
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On 12/11/2020 11:46 PM, Brian Valente wrote: Hi Paul
i agree DEC looks pretty?good. again the amount of backlash will change through the night, primarily due to changes in your scope orientation (i.e., altitude)
RA seems to me to show issues related to a bad PEC. you have a lot of back-and-forth OK, in the past couple days I have learned a lot about how to evaluate my guide logs. The following picture emerges after looking at ALL my old logs (about ten of them) in the PHD2 log viewer. PEC was off for most if not all of these because I never found it to improve the performance. Now I know why. Seeing was variable and mostly bad, but that would only contribute noise to the frequency analysis, right? 1. In all but one or two of my old logs, I see the worm and worm/2 signals but the predominant signal by far in the frequency domain is the 76.2s signal from the worm bearing(s). 2. Because the 76.2s signal is not phase locked to the worm period, it cannot be removed with PEC training and in fact will likely be magnified by PEC because the G2 does not average multiple training runs (which would average out the 76.2s signal and reduce or remove it from the resulting corrections). 3. If I am interpreting the log viewer correctly in the frequency analysis, the corrected error at 76s is a maximum of about 0.8". Since that is the predominant signal and the corrected error of the other signals is lower, is this enough error to worry about? My seeing is RARELY that good ;) 4. Would it be reasonable to assume that the worm bearing signal should never exceed the 240s worm signal and if so, is it time to do a simple RA worm bearing and stop screw adjustment to see if it can be reduced? Right now, the RA is untouched from as-received. Note that all this analysis is on guide logs with guiding enabled. I do not have any unguided logs to analyze and according to the weather forecast, I will not have an opportunity to make one for quite some time :( Paul -- Paul Goelz Rochester Hills, MI USA pgoelz@... www.pgoelz.com
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Re: Losmandy Update: Covid
Very sorry to hear, Brian. Wishing all a speedy return to good health.
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Re: Losmandy Update: Covid
Speedy recovery to everyone and your families, Brian!
Regards,
? ? ?-Paul
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On Sun, Dec 13, 2020 at 10:47 PM, Brian Valente wrote:
Hi everyone
?
i apologize for being offline for a day or so
?
Losmandy has been hit by Covid. Pretty much the whole Losmandy office tested positive. No one is critically ill, but several are bed-bound.?
?
Unrelated, some of our suppliers also tested positive as well, including complete shops. Wow, this thing moves fast and leaves no one behind.
?
This is despite our best efforts to be as careful as possible, following all protocols and recommendations from CDC and local health officials.?
?
?
?
I am writing so that you know responses may be slower than anticipated, and shipping is slowed down as well.?
?
We wanted you to know we are still doing everything we can to keep things moving, but it may be a bit before we are back to normal.
?
Brian
--
Brian?
?
?
?
Brian Valente
portfolio
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Re: Losmandy Update: Covid
Extremely sorry to hear this. Wishing everyone a speedy recovery.
V.P
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Re: Losmandy Update: Covid
Sorry to hear this. Best wishes to everyone.?
Jamie
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Re: [Gemini_users_io] Losmandy Update: Covid
Wow...awful.? Very sorry to read this news Brian.??
Pass our heartfelt best wishes to your company and its families for a speedy recovery and mild symptoms.??
Sincerely, Michael
On Sun, Dec 13, 2020, 7:47 PM Brian Valente < bvalente@...> wrote: Hi everyone
i apologize for being offline for a day or so
Losmandy has been hit by Covid. Pretty much the whole Losmandy office tested positive.
No one is critically ill, but several are bed-bound.?
Unrelated, some of our suppliers also tested positive as well, including complete shops. Wow, this thing moves fast and leaves no one behind.
This is despite our best efforts to be as careful as possible, following all protocols and recommendations from CDC and local health officials.?
I am writing so that you know responses may be slower than anticipated, and shipping is slowed down as well.?
We wanted you to know we are still doing everything we can to keep things moving, but it may be a bit before we are back to normal.
Brian -- Brian?
Brian Valente portfolio
|
Re: Losmandy Update: Covid
So sorry to hear.? Please, everyone take care of yourselves and each other.? Best wishes to all.
On Sun, Dec 13, 2020 at 10:47 PM Brian Valente < bvalente@...> wrote: Hi everyone
i apologize for being offline for a day or so
Losmandy has been hit by Covid. Pretty much the whole Losmandy office tested positive.
No one is critically ill, but several are bed-bound.?
Unrelated, some of our suppliers also tested positive as well, including complete shops. Wow, this thing moves fast and leaves no one behind.
This is despite our best efforts to be as careful as possible, following all protocols and recommendations from CDC and local health officials.?
I am writing so that you know responses may be slower than anticipated, and shipping is slowed down as well.?
We wanted you to know we are still doing everything we can to keep things moving, but it may be a bit before we are back to normal.
Brian -- Brian?
Brian Valente portfolio
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Mearl Balmer
Paul Kanevsky
Jamie Amendolagine
Michael Herman