Not personally, but I would think that anyone using a rotational dome would need some way to position it so that the telescope is not blocked by the slot. Since the "Active" mode doesn't do the geometry, unless you have a very wide slot that goes significantly past vertical, "Passive" is really the only option. I was unable to test POTH, as you suggested, since it is depricated, no longer part of the ASCOM 6.5SP1 distribution, and I could not find a download of it from a reliable source. I would expect, however, that it would have a similar issue, either needing to know where the telescope is slewing to or slewing the dome by polling the telescope's position periodically. SGP has slaving that works well and has a minimum polling frequency of 1 seconds. But it was made with the intention of some other application connecting to SGP to query the dome slewing state. I don't know of any other solution than DeviceHub if you are running up-to-date ASCOM.
Of course if you have a roll-off, open clam shell, or are just outside, you don't need any dome support all!
I'm guessing, based on my serial number, that there are a little over 120 Mach2's out there that came with APPM. I don't know how many copies of APPM are being used by 1100 and 1600 users, nor how many of those users along with other Mach2 owners have rotational domes (I think roll-offs are much more popular), but I am a bit surprised that this has not been brought up before. The Mach2 is fairly compact and I am using a 4" refractor, so my geometry ought to be about as optimal as it gets. The slot in my dome looks to be a similar proportion to other domes I've seen; it is by no means overly narrow. And yet, in Active mode, for most of the sample points, the dome ends up covering more than half of the telescopes view, so I need to use Passive mode. Maybe I really am doing something totally wrong and stupid, but I sure don't know what that would be...
- Shane
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On 2/28/2021 7:19 PM, Ray Gralak wrote: Shane,
As far as the APPM specific commands, could you allow a connection to DeviceHub to send the info necessary for the slew and then send the "special sauce" directly to the AP V2 driver? I would have to bring this up with Marj to see if this is something A-P would want to have implemented and supported. Are you aware of any others that would want this feature?
-Ray
-----Original Message----- From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Shane Ramotowski Sent: Sunday, February 28, 2021 4:29 PM To: main@ap-gto.groups.io Subject: Re: [ap-gto] APPM with Dome Questions
When using DeviceHub, if you are connected to both DeviceHub's telescope and dome drivers, then when you issue a telescope slew, DeviceHub knows the target RA and DEC and can start a dome slew to the azimuth that the telescope will end at.
If you cannot connect to the DeviceHub telescope and/or dome, then DeviceHub uses a polling scheme to ask where the telescope is and then send the dome to the correct azimuth. The polling period, unfortunately, seems to have a minimum of 5 seconds. So, during an APPM run, APPM will tell the telescope to slew. Sometime less than 5 seconds later, DeviceHub will retrieve the current RA/DEC from the telescope and start the dome slewing to that position. For longer slews, the telescope may still be moving. 5 seconds after the dome arrives at the indicated position, it finds that the telescope has moved again (in acutality, the telescope never stopped moving, simply completing its original slew. So DeviceHub issues a second slew to get to the final position.
So for the Passive settings in APPM, I have to use timeouts long enough to account for 2 polling periods plus 2 slew times to ensure that the dome is really in position before imaging starts. I can't let APPM catch the dome in a stopped state between two dome slews. I hope that makes sense.
I ran a large model last night using DeviceHub. I lost 5 points in total, which isn't that bad. Three of them were because of the bodaciously bright almost full moon and the other two were bad luck in the timing of long slews from the end of on string of points to the start of the next. I was concerned that DeviceHub would not position properly for the counterweight-up points, but it did so correctly. The model run took a lot longer than I expected since I was waiting 40 seconds (usually unnecessarily) for each point to give the dome time to get into position in case it was a long slew.
I really don't know if supporting DeviceHub's telescope driver will work. I'm assuming that if the SideOfPier property is set correctly when the slew is issued, DeviceHub will go to the correct location even if it ends up counterweight-up. But I haven't tested that and I really don't know how--well I guess I could write a little program to do that. I will do so if you are considering adding such support and the results of that test would help.
As far as the APPM specific commands, could you allow a connection to DeviceHub to send the info necessary for the slew and then send the "special sauce" directly to the AP V2 driver?
- Shane
On 2/28/2021 8:10 AM, Ray Gralak wrote:
Hi Shane,
One more question, Ray: In APPM, is there a way to connect to the DeviceHub telescope or is it locked to the AP ASCOM driver? You would not want to connect APPM to the DeviceHub telescope. APPM uses some commands that the DeviceHub would not be able to pass through to the AP V2 driver.
That said, what is the use case for this?
-Ray
-----Original Message----- From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Shane Ramotowski Sent: Sunday, February 28, 2021 3:52 AM To: main@ap-gto.groups.io Subject: Re: [ap-gto] APPM with Dome Questions
One more question, Ray: In APPM, is there a way to connect to the DeviceHub telescope or is it locked to the AP ASCOM driver?
Thanks - Shane
On 2/27/2021 8:09 PM, Shane Ramotowski wrote:
Ahh, I think it understand. I use DeviceHub to do the slaving, but still connect to the DeviceHub dome with APPM. I will try that and see what happens.
Thanks - Shane
On 2/27/2021 5:27 PM, Ray Gralak wrote:
Shane,
OK. I'll wait for the ASCOM folks to add the APIs that you want before I try to use "Active" mode again. I think you misunderstood. ASCOM is not planning to add those APIs.
For the second part of my reply, I guess I did not make it clear enough that I was using DeviceHub not allowing APPM to connect to the dome, since APPM cannot send the dome to the correct position an DeviceHub can. _I am simply trying to understand what I'm doing wrong when setting up "Passive" parameters in the "Dome Settings" box.__ In passive mode, APPM only needs to poll the Dome's slewing state to work. If you can't do that then APPM won't be able to tell when the dome is done slewing.
If Device Hub won't let APPM connect to the Dome driver you can use the older ASCOM POTH application, which allows multiple applications to connect to an ASCOM driver.
So can you please tell me what settings I can use for "Delay before staring dome slew check" and "Settle time after dome stops slewing" to ensure that I end up with at least 30 seconds between the end of the telescope slew and the start of imaging? First, the two parameters only have meaning when you are connected to a Dome driver. If you are not connected they won't be used.
"Delay before starting dome slew checking"
The number of seconds before APPM will start checking the dome driver's slew state. This delay allows the dome driver time to initiate dome movement that will be reflected by reading "True" from the Dome driver's "Slewing" property. If the value is False when read, then dome slewing will be considered completed.
"Settle time after dome stops slewing"
The number of seconds to delay slew completion after the Dome driver's "Slewing" property reads "False".
-Ray
-----Original Message----- From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Shane Ramotowski Sent: Saturday, February 27, 2021 2:16 PM To: main@ap-gto.groups.io Subject: Re: [ap-gto] APPM with Dome Questions
OK. I'll wait for the ASCOM folks to add the APIs that you want before I try to use "Active" mode again.
For the second part of my reply, I guess I did not make it clear enough that I was using DeviceHub not allowing APPM to connect to the dome, since APPM cannot send the dome to the correct position an DeviceHub can. _I am simply trying to understand what I'm doing wrong when setting up "Passive" parameters in the "Dome Settings" box.__ _ So can you please tell me what settings I can use for "Delay before staring dome slew check" and "Settle time after dome stops slewing" to ensure that I end up with at least 30 seconds between the end of the telescope slew and the start of imaging? Assume that I did not change the default telescope slew of 900X. The log entry I posted is from a session that used DeviceHub with "Delay before starting dome slew check" set to 30 seconds and "Settle time after dome stops slewing" set to 10 seconds. You can see that the time between the start of the telescope slew and the the start of imaging is about 12 seconds. So, clearly, I am not understanding how these two parameters work.
Thank you - Shane
On 2/27/2021 2:16 PM, Ray Gralak wrote:
Shane,
APPM's "Active mode" sends the telescope's destination coordinates to the dome ASCOM driver. In this case, it is the responsibility of the driver or intermediate
application to translate the RA/Dec coordinates to the appropriate dome position. Hmmm, so how does that work? What part of the ASCOM dome API would that be? <https://ascom-standards.org/Help/Developer/html/T_ASCOM_DriverAccess_Dome.htm>
Again, APPM does not do dome calculations (nor is there a plan for it to do that). IMO, the ASCOM Dome API is missing a way to send scope Ra/Dec/pierside to the Dome driver. ASCOM makes such a big deal about abstracting away telescope applications from the hardware, but the incomplete Dome API pretty much forces the use of a third-party application.
I think each dome manufacturer should each create their own drivers that should take into account the telescope and mount dimensions. It would have made life much easier for each application developer that has had to implement dome coordinate transformations in their applications.
> In "Passive mode" APPM waits for the dome to finish slewing by polling the dome's driver (or intermediate application).
That is exactly what I expected. What should I set the two passive values to to ensure that the imaging doesn't start for, say, 1 minute after the scope stops slewing? Or am I not understanding the meaning of those two fields and their documentation in the manual? To use passive mode the dome driver or application must be slaved to the telescope. In this case APPM just polls the slewing state until dome slewing stops. If slaving can't be done, there is an option in APPM to pause after each point, which would allow you to position the dome opening.
The total time between the start of the point's processing and start of it's imaging is about 12 seconds. Shouldn't that be at least 40 seconds to allow the dome delay and settle times to happen? What am I misunderstanding?. There are no dome messages in your post so I can't tell you what happened. Are you sure that you had APPM connected to your Dome application?
BTW, the problem might be that you are using the ASCOM Device Hub instead of the older POTH dome handling. The behavior is dome behavior is different in Device Hub, and it sounds like the author left out some old functionality.
-Ray
-----Original Message----- From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Shane Ramotowski Sent: Saturday, February 27, 2021 11:32 AM To: main@ap-gto.groups.io Subject: Re: [ap-gto] APPM with Dome Questions
Ray, thanks for the reply, but I don't really see anything that will help.
APPM's "Active mode" sends the telescope's destination coordinates to the dome ASCOM driver. In this case, it is the responsibility of the driver or intermediate
application to translate the RA/Dec coordinates to the appropriate dome position. Hmmm, so how does that work? What part of the ASCOM dome API would that be? <https://ascom-standards.org/Help/Developer/html/T_ASCOM_DriverAccess_Dome.htm>
I am definitely returning false fort the CanSlave and Slaved properties, since there is no hardware-based slaving capability in the dome controller. And I don't see way to "send the telescope's destination coordinates" to the ASCOM driver.
The call that the ASCOM driver receives from APPM is "SlewToAzimuth()" but I think you are basing that azimuth on the center of the dome rather than the position of the telescope, which can be significantly different--consider the initial slew to zenith in which the RA axis rotates west and level and the DEC axis point strait up. The telescope is several inches West of the center of the mount. From what I understand, if you are going to use SlewToAzimuth(), you need to consider this.
If you look at ASCOM's DeviceHub, written by Rick and Pete, who answer most of the dome-related questions posted to the ASCOM Driver and Application Development Support Forum, it has a whole section for dome and mount geometry in it's setup section to allow slaving.
> In "Passive mode" APPM waits for the dome to finish slewing by polling the dome's driver (or intermediate application).
That is exactly what I expected. What should I set the two passive values to to ensure that the imaging doesn't start for, say, 1 minute after the scope stops slewing? Or am I not understanding the meaning of those two fields and their documentation in the manual?
Here is a log excerpt from one of my attempts last night. Under Settings->Dome Settings, Passive is selected, "Delay before starting dome slew checking" is set to 30 seconds and "Settle time after dome stops slewing" is set to 10 seconds.
0467221 2021-02-26 20:46:21.965: Info, State Machine, Entering State=SlewNext 0467222 2021-02-26 20:46:22.103: Info, SlewNext, Starting Slew to Point 3 RA: 08h 30m 06.56s, HA: -01h 20m 00.00s, Dec: -10° 00' 00.0") 0467223 2021-02-26 20:46:22.105: Info, Slew Next, East=True, Dec=-10, HA=-1.33333333333333, MerDelay=-0.25, MerOffset=0 0467224 2021-02-26 20:46:22.105: Info, Meridian, Setting Meridian Delay to -0.25 (-00h 15m 00.00s) 0467225 2021-02-26 20:46:22.144: Info, SlewAsync, Begin UnSAFE Slew to RA/Dec: 8.501824 / -10.000000 ( 08h 30m 06.56s / -10° 00' 00.0") 0467226 2021-02-26 20:46:22.215: Info, State Machine, Entering State=PreSlewing 0467227 2021-02-26 20:46:25.482: Info, State Machine, Entering State=Slewing 0467228 2021-02-26 20:46:30.722: Info, State Machine, Entering State=StartSettle 0467229 2021-02-26 20:46:30.741: Info, StartSettle, Starting Settle wait time 0467230 2021-02-26 20:46:30.970: Info, State Machine, Entering State=WaitSettle 0467231 2021-02-26 20:46:32.974: Info, WaitSettle, Settling Time Complete 0467232 2021-02-26 20:46:33.022: Info, WaitSettle, Finished Slew to Point 3 0467233 2021-02-26 20:46:33.022: Info, WaitSettle, RA/Dec: 8.501833 / -10.000000 ( 08h 30m 06.60s / -10° 00' 00.0") 0467234 2021-02-26 20:46:33.022: Info, WaitSettle, HA/Dec: -1.329942 / -10.000000 (-01h 19m 47.79s / -10° 00' 00.0") 0467235 2021-02-26 20:46:33.226: Info, State Machine, Entering State=StartImage 0467236 2021-02-26 20:46:33.260: Info, State Machine, Starting Exposure, Duration=5 LST=7.17191416666667 (07h 10m 18.89s) 0467237 2021-02-26 20:46:33.260: Info, State Machine, LST mid image=7.1727475 (07h 10m 21.89s) 0467238 2021-02-26 20:46:33.260: Info, StartTakeImage, Sequence Generator Pro: Binning=1, Subframe Type: 0, Duration=5, IsDarkFrame=False
The total time between the start of the point's processing and start of it's imaging is about 12 seconds. Shouldn't that be at least 40 seconds to allow the dome delay and settle times to happen? What am I misunderstanding?
The dome controller and ASCOM driver do handle Slewing property correctly, returning TRUE from the time that the slewToAzimuth() is issued until the dome is stopped at the requested position, then returning FALSE until the next slew is issued Sometimes, DeviceHub or SGP will end up issuing more than one slew to get the dome to the final position. The slaving software notices that the telescope has moved and starts an azimuth slew to where is while the telescope is still moving. Once the dome arrives at that position, another azimuth slew to get to where the telescope finally stopped. Last night, the longest time that such multiple slews took was about 20 seconds. That is why I set the "Delay before starting dome slew checking" to 30 seconds. I though that would make APPM not even check for a dome slew until the dome was in place and had stopped moving. Instead, it seemed to have made no difference: the imaging started almost as soon as the telescope arrived at its position.
Thanks - Shane
On 2/27/2021 10:06 AM, Ray Gralak wrote:
Hi Shane,
APPM's "Active mode" sends the telescope's destination coordinates to the dome ASCOM driver. In this case, it is the responsibility of the driver or intermediate application to translate the RA/Dec coordinates to the
appropriate dome position.
In "Passive mode" APPM waits for the dome to finish slewing by polling the dome's driver (or intermediate application).
So, it seems that your dome's ascom driver (or intermediate application) may not be correctly indicating when
the dome is slewing.
-Ray
-----Original Message----- From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Shane Ramotowski Sent: Friday, February 26, 2021 9:19 PM To: main@ap-gto.groups.io Subject: [ap-gto] APPM with Dome Questions
Hi gang,
I am the proud owner of a brand new (well 2 weeks) Mach2 and tried to do my first APPM model tonight. I'm having problems with the dome control and hope someone can point in the right direction.
My observatory is a ClearSkys (I don't think they are around anymore) 8 ft dome. The pier is centered and the bottom of the mount is just about even with the bottom of the dome. The rotation control is homemade (my COVID quarantine project) and works very will with both ASCOM DeviceHub and SGP. I'm using SGP for image capture and plate solve.
I can't figure out how to set up APPM to control the dome properly. If I use "Active" in the "AP Point Mapper - Dome Settings" panel, APPM seems to do it's calculations based on the center of the dome instead of where the telescope is. This is not surprising since I can't seem to find any where in the program or the documentation to set the mount and telescope geometry. I suppose, since APCC knows that I'm using a Mach2, it _could_ already know roughly how far from the center of the RA/DEC axes intersection the bottom of my telescope is. But I don't see anyway that it could know where the center of my OTA is. I really don't think it's using the parameters from 3D view; I haven't set that up, but the default is a much larger diameter telescope than mine.
Anyway, when I use "Active", I end up imaging across the edge of the slot because the slot is positioned for the center of the mount instead of where the telescope is. Most of the images ended up plate solving anyway, but since the stars are all diffraction spikes, I don't know the quality of those solutions. The initial slew to meridian is probably the worst because the dome is in the exact opposite position than it should be and my slot just goes barely past vertical. I checked the ASCOM logs on the PC and my ASCOM debug screen on the dome controller. The dome _is_ slewing to the position that APPM requests; that position just doesn't seem to be based on where the telescope is.
Can anyone tell me what I'm missing? Where do I enter the offsets for the mount/scope geometer so that APPM can got to the correct position?
So, after trying "Active", I swiched to "Passive" and tried with two different dome slaving programs: ASCOM Device Hub and SGP. For "Delay before starting dome slew checking", I used values ranging from 5 to 30 seconds. For "Settle time after dome stops slewing", I used values from 1 to 20 seconds. I didn't see any effect when changing these settings; in all cases the the telescope slewed to the next position and started imaging a few seconds after it got there--many seconds before the dome was in position. None of those images solved since the dome was in the way. Again, I can't figure out what I'm doing wrong--it's like I'm not even changing the values. Is there another setting that I'm missing that enables these timeouts?
I'm sure someone else has successfully done an APPM run from an automated dome! What am I missing?
Thanks - Shane
-- Shane Ramotowski kor@... https://www.kor-astro.net
-- Shane Ramotowski kor@... https://www.kor-astro.net
-- Shane Ramotowski kor@... https://www.kor-astro.net
-- Shane Ramotowski kor@... https://www.kor-astro.net
-- Shane Ramotowski kor@... https://www.kor-astro.net
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