PHD2 help

[souls33k3r]

Hi All,

I do have two questions but i'll separate them in to two thread just so the questions don't get side tracked and might even help someone in the future if they're looking for specific answer.

So basically i'm a super beginner in the world of PHD and i must admit i'm getting the hang of the software. (Is it just me or does anyone keep an eye on the graph religiously like i've always done. MaximDL before and now PHD2)

Before i ask, i have to set up and tear down my kit every time so the location of my setup can be a few feet away every time.

First question: How of often should one calibrate PHD2? (assuming i'm imaging the same target over a couple of nights apart and slew to a different target). Is it always a necessary thing to calibrate at DEC0 in the south? If it's not necessary to calibrate, how can you skip PHD2 to calibrate? Last night i hit "Connect > Loop > Green guide button" and it still calibrated but the calibration happened where my object was for the night.

Second Question: I often get PHD2 star loss message, but PHD2 doesn't automatically choose a new star. In fact i have to manually do the "ALT+S" to find a new guide star

Third Question: The last three times when i've started using PHD2, the view window where the stars show up nice and sharp at say 2s exposure, then at some point out of no where the stars go away and if i drop to 1.5s, the stars show up again and guiding starts fine, then push it back up to 2s and stars are fine again. But i keep having to drop from 2s all the way down to 1s. Is there a way to make PHD2 change the exposures without me having to do that?

Sorry if these question sound quite noobish but i'm only just learning my ways around this software.

Thanks in advance

[spillage]

Hi 

I am no expert but if you have to set up your kit every session then you need to calibrate every time. If you are using the drift align option then I normally slew to the first point, run calibration and then drift align.

I do not think PHD2 will automatically choose a star for you out the box but I am sure that using imaging software like apt or sgp can send this command to phd2. Mine sometimes loose the star and the box goes a red colour but will eventually pick up back up. I have just put this down to seeing conditions and do not really let it bother me that much.

hope this helps a bit.

 

Mark.

[ChrisEll]

1. No, you don't have to calibrate every time as long as you use the same guiding setup and the camera is orientated the same (I mark my guide cam with a sticker to denote TOP and always set it up that way). If you use an OAG ditto. I've calibrated at Dec 40-50 ok. Next time just click the crosshair button to start guiding... there's an Auto Restore Calibration setting which I think needs to be ticked.

2. That's normal.

3. Odd.

[souls33k3r]

7 minutes ago, spillage said:

Hi 

I am no expert but if you have to set up your kit every session then you need to calibrate every time. If you are using the drift align option then I normally slew to the first point, run calibration and then drift align.

I do not think PHD2 will automatically choose a star for you out the box but I am sure that using imaging software like apt or sgp can send this command to phd2. Mine sometimes loose the star and the box goes a red colour but will eventually pick up back up. I have just put this down to seeing conditions and do not really let it bother me that much.

hope this helps a bit.

 

Mark.

Cheers for your input Mark.

Sorry i should've said, i do indeed use SGP

[souls33k3r]

12 minutes ago, ChrisEll said:

1. No, you don't have to calibrate every time as long as you use the same guiding setup and the camera is orientated the same (I mark my guide cam with a sticker to denote TOP and always set it up that way). If you use an OAG ditto. I've calibrated at Dec 40-50 ok. Next time just click the crosshair button to start guiding... there's an Auto Restore Calibration setting which I think needs to be ticked.

2. That's normal.

3. Odd.

Cheers for your reply Chris

1) I always unscrew my guide cam from the guidescope so i guess i will have to keep it as it is or somehow find a way to do that before putting it back in the box.

2) If this is normal, is there a way in SGP or PHD2 that if the star gets lost it should choose the next star? The issue is, if the star gets lost, SGP will abort the sequence which is the last thing i need if in case i fall asleep when i'm looking.

3) Odd indeed, was wondering if (again) there is a way in PHD2 or SGP to set it up to choose different exposure lengths if this happens.

[Adreneline]

Hi,

I'm no expert either but I have been using PHD for 18 months now and I've learnt what works for me. I also have to setup and strip down everytime so I've got pretty slick at finding a system that consistently works for me. 

Re. Qu. 1 : I only calibrate PHD once I am satisfied I have the scope correctly aligned. I PA using the polarscope and my eyeball and my iphone app. I then slew my way to my target stopping off at a few 'regular' points along the way to calibrate the scope with CdC (which I have discovered needs to be set to Equatorial Coordinates and J2000 every time I use it otherwise the GoTo can be hopelessly off; the save settings on exit doesn't work for me). Having arrived at the target I focus up the imaging scope and then run up PHD and calibrate at the target location. If I change targets during the evening (a rare event with our weather!) I recalibrate PHD at the new target. I have never calibrated at DEC0 - I don't understand why I might want/need to do so. I'm pretty OCD'ish about my graph but overall I'm looking to achieve around 0.5" RMS which I do pretty much every time unless the seeing is poor (and I get a heads-up on that if I can't get below 1.5 on my FWHM focus figure). I tried drift alignment a few times and didn't do any imaging - I decided it wasn't for me!

Re. Qu. 2 & 3 : I used to get star lost messages a lot when I used a colour guide camera and the SW finder scope that came with my SWED80DS-Pro, but I also used to find the camera would become 'unavailable' so I put it down to USB issues. Since I changed to a mono ZWO camera and upgraded to the new SW dedicated guide scope I've not had anything like the problems I used experience. The biggest problem with the original guide scope was getting it to focus; the new scope is far better in this respect. I also used to find all the stars 'disappearing' but again since I changed camera and guide scope my guiding experience has been much better. I can see no star trailing on 600s NB exposures and that is with a carefully balanced, standard NEQ6 Pro mount - no mods or upgrades.

HTH.

 

 

[Jkulin]

I watched these two videos a few times and have to admit that without it I would have been lost: -

It made things so much easier to understand and I now find my making knowledgeable adjustments to improve the guiding.

I set up and put away each night, but I do have a permanent pier and I only recalibrate if I think I have a problem which is very rare.

HTH

[ChrisEll]

1 hour ago, souls33k3r said:

Cheers for your reply Chris

1) I always unscrew my guide cam from the guidescope so i guess i will have to keep it as it is or somehow find a way to do that before putting it back in the box.

2) If this is normal, is there a way in SGP or PHD2 that if the star gets lost it should choose the next star? The issue is, if the star gets lost, SGP will abort the sequence which is the last thing i need if in case i fall asleep when i'm looking.

3) Odd indeed, was wondering if (again) there is a way in PHD2 or SGP to set it up to choose different exposure lengths if this happens.

2. Not AFAIK

3. Again NAFAIK... I wonder if it's a driver issue. I've not seen this happen. If you have another guide cam or can borrow one try that. Perhaps the star's SNR or focus is an issue...?

[souls33k3r]

1 hour ago, Adreneline said:

Hi,

I'm no expert either but I have been using PHD for 18 months now and I've learnt what works for me. I also have to setup and strip down everytime so I've got pretty slick at finding a system that consistently works for me. 

Re. Qu. 1 : I only calibrate PHD once I am satisfied I have the scope correctly aligned. I PA using the polarscope and my eyeball and my iphone app. I then slew my way to my target stopping off at a few 'regular' points along the way to calibrate the scope with CdC (which I have discovered needs to be set to Equatorial Coordinates and J2000 every time I use it otherwise the GoTo can be hopelessly off; the save settings on exit doesn't work for me). Having arrived at the target I focus up the imaging scope and then run up PHD and calibrate at the target location. If I change targets during the evening (a rare event with our weather!) I recalibrate PHD at the new target. I have never calibrated at DEC0 - I don't understand why I might want/need to do so. I'm pretty OCD'ish about my graph but overall I'm looking to achieve around 0.5" RMS which I do pretty much every time unless the seeing is poor (and I get a heads-up on that if I can't get below 1.5 on my FWHM focus figure). I tried drift alignment a few times and didn't do any imaging - I decided it wasn't for me!

Re. Qu. 2 & 3 : I used to get star lost messages a lot when I used a colour guide camera and the SW finder scope that came with my SWED80DS-Pro, but I also used to find the camera would become 'unavailable' so I put it down to USB issues. Since I changed to a mono ZWO camera and upgraded to the new SW dedicated guide scope I've not had anything like the problems I used experience. The biggest problem with the original guide scope was getting it to focus; the new scope is far better in this respect. I also used to find all the stars 'disappearing' but again since I changed camera and guide scope my guiding experience has been much better. I can see no star trailing on 600s NB exposures and that is with a carefully balanced, standard NEQ6 Pro mount - no mods or upgrades.

HTH.

 

 

Cheers mate.

1) I can't remember where but read it here on SGL that calibrating at DEC 0 is recommended which is what i've started doing. Not that i find it made any difference but just following the norms i guess. Previously when i used the inbuilt MaximDL guiding system, i always used to calibrate at the intended target i was imaging and that never failed me. I used to do 3 min exposures without any issue. Stretched it to 10 min once but then quickly gave up that idea because 10 minutes is too long for me to wait and see if my sub is fine or not

2 & 3) I do indeed use a mono camera. It's a QHY5L-II mono camera with the QHY miniGuidescope. This guidescope has never failed me because firstly i can find stars all over the field and the camera is sensitive enough to pick them. It's got a focuser mechanism at the front lens so focus is not an issue. I remember Bern from modern astronomy once mentioned to me that it's ok for the stars to be a bit out of focus with this setup because it's the centeroid that the guide cam has to work with. Needless to say, i've done both in and out of focus and it worked fine in MaximDL but only started to see this when i started using PHD. Currently i'm doing 300s exposures without a hitch but it's this guide star lost and the weird behavior with stars disappearing and then re-appearing as i change the guide exposure

48 minutes ago, Jkulin said:

I watched these two videos a few times and have to admit that without it I would have been lost: -

It made things so much easier to understand and I now find my making knowledgeable adjustments to improve the guiding.

I set up and put away each night, but I do have a permanent pier and I only recalibrate if I think I have a problem which is very rare.

HTH

Cheers mate, i do remember going through all of this and initially setting up my PHD using this method. Truth be told, i've never had to mess about with my PHD2 settings, guiding numbers might be bad but stars are very round even after 5min exposures. I don't think i'll be going over the 5min mark with my current CMOS camera (ASI1600MM-C)

25 minutes ago, ChrisEll said:

2. Not AFAIK

3. Again NAFAIK... I wonder if it's a driver issue. I've not seen this happen. If you have another guide cam or can borrow one try that. Perhaps the star's SNR or focus is an issue...?

Cheers mate.

2 & 3) I sincerely do hope there is a way or at least how are people doing un-attended imaging or counter this sort of an issue when using SGP and PHD2.

[Freddie]

Obviously you can only calibrate at dec0 if your Mount is connected to a control prog on your computer and therefore PHD will always know where your mount is pointed. If not, calibrate on each target.

[souls33k3r]

14 hours ago, Freddie said:

Obviously you can only calibrate at dec0 if your Mount is connected to a control prog on your computer and therefore PHD will always know where your mount is pointed. If not, calibrate on each target.

Yes i use stellarium for that.

I'm wondering if there are any PHD2 gurus around that can give me guidance on the issues that i'm having.

[souls33k3r]

Thought i would give an update on this thread.

1) Will continue to calibrate at Dec0 while i still can. New house location will have new questions but for now this is now answered.

2) I have found a way to make sure i do not get star loss error message. When SGP begins to guide, i go through star selection using the ALT+S until i find nearly saturated star and then start guiding. 2 nights in a row and have not had any issues

3) What i ended up doing was choose "Auto" as my exposure settings and that has not failed me all night last night (Started imaging at 10pm up until 4:30am)