Problems with PHD2, first time guiding!

[Quetzalcoatl72]

I got guiding working last night for the first time(sort of) everything was green, however the graphs were all over the place, I was told in youtube not to worry about those, but they looked nothing like the tutorial videos, very erratic. Anyway I will try to recall last night what happened, my memory is not so great, set up as follows;

• Levelled tripod + mount + rough PA + added all equiptment
• Balanced scope slightly east heavy (RCT f/8 1600mm) with ZWO ASI120MC(old model) guide cam
• Set up a pretty much perfect polar alignment with Sharpcap's polar assist on my Windows 7 Laptop
• Did a quick 1 star to Arcturus then set pc direct mode on the handset and fired up PHD2
• Connected mount and camera then changed the RA and DEC rate to 0.90 as was told from last time
• Looping, auto selected star and started calibration, cal complete everything green, guiding then begun

(I will note that the mount made sounds I've never heard before when it was calibrating like spaceship noises I can't explain, I've a history of my mount making knocking sounds in DEC and coffee grinding noises in both ascensions. Picture also violently wobbles when making slight movements with the directional keys) anyway...

• Once I saw that It was guiding I slew to my target for the night, The Cat's Eye nebula.
• I then did a 5 minute exposure something I've never done before and the stars were still egg shaped, not too horrendous but I reckon it could do many 4 minutes without fail
• I noticed not everything was green, the SNR was orange and at 8.0+ not 15+ like originally
• I then realized that the target wasn't the best thing to image on a almost full moon night so I then slew from there to Sunflower Galaxy where it stayed the rest of the night.
• The snr had dropped to 4.0+, I didn't know how to increase it, I-re calibrated a couple of times restarted phd2 etc and it wasn't really working well as the guide camera was incredibly grainy for some reason, It still said it was guiding so I just left it and hoped for the best
• I started my exposures 10 x3min for reference, when I went back outside I noticed all the pictures were star trailing, like it wasn't even tracking at all, and noticed the finderscope was pretty dewed up and the camera couldn't see any stars, very grainy.

In the end I just packed up my laptop and did 30x3mins the normal way, with terrible results as I'm used to at this moment, 40-50% of the images were usable and stacking them didn't yield anything probably due to the moon. If anyone can help me have a better chance at guiding next time that would be great! I will include the calibration image and the guide logs from that night if that helps.

PHD2_DebugLog_2021-04-25_221334.txt PHD2_GuideLog_2021-04-25_221334.txt

[Astrosharkey]

What mount are you using, and what size is your guide scope?  Calibration looks good though.

[Quetzalcoatl72]

5 minutes ago, Astrosharkey said:

What mount are you using, and what size is your guide scope?  Calibration looks good though.

eq6 pro, and a astro essentials 50mm scope. aperture is 240

[JSeaman]

HEQ5/6 and ASI 120 2x2 guide scope from the logs

I see at 11pm you calibrated and started guiding, this worked for 1 minute and 35 seconds

It then started again at ~11:07pm, from your text above it reads that you started guiding then slewed the mount? You should slew to the target and then start guiding

It guided OK for about 15 minutes then stopped. The guiding looked good and the star mass was fairly steady, this looks OK up until here

At 11:30 ish it goes downhill, you start guiding again and have a really erratic star mass, was it cloudy? 

Recalibration at 11:45 was really good again (no issue with RA/DEC Orthogonality) but guiding was terrible, massive swings, I see you knocked it up to 2.5 seconds, did you change anything else?

At 1:22 another cal was attempted but this failed

 

So you had a patch in the middle which worked

Edited April 26, 2021 by JSeaman

[Quetzalcoatl72]

14 minutes ago, JSeaman said:

It then started again at ~11:07pm, from your text above it reads that you started guiding then slewed the mount? You should slew to the target and then start guiding

At 11:30 ish it goes downhill, you start guiding again and have a really erratic star mass, was it cloudy? 

Recalibration at 11:45 was really good again (no issue with RA/DEC Orthogonality) but guiding was terrible, massive swings, I see you knocked it up to 2.5 seconds, did you change anything else?

There was the odd few clouds but I don't recall at what times, it was clear of them later on though. I changed it to 2.5 as the camera looked like t.v. static, I couldn't get the quality back to what it was on the first cal at Arcturus which was black background bright star's. I didn't think clouds would make the camera do that effect, I thought something had changed, or the camera was broke. The massive swings could be me rotating the main camera to get the galaxy horizontal, that's all I changed.

I have problems with the goto, have for a while now, I always position with the ra and dec clutch on a bright star near the target before I slew to it and start imaging. Upon slewing it just isn't centered at all, somewhere at the top or far left on the camera screen usually. I often wondered if bad gears effect the goto?

[JSeaman]

OK the black background with white stars is usually focus or too long an exposure, maybe reduce it down

Clouds will have a huge effect though

As soon as you're guiding don't touch anything, if you need to rotate the camera etc, pause guiding then start looping, reselect stars and start guiding again. Otherwise it will think the mount's moving as you do things and try to correct

Regarding the goto, do you use cartes du ciel or something? It would be worth clearing your alignment points, slewing to a bright star and then moving the scope there with the clutches off and calling this point 0

[Quetzalcoatl72]

I've never heard of cdc, is it freeware and what does it do and how do I clear my alignment points? It's very hard making fine adjustments while holding the mount etc, I'm used to the handset, aligning with the directional keys and the pressing esc and holding esc to re-align. My main camera is a dslr so I can't see the exposure live otherwise I'd align on the object I want to image. I have to keep taking 30+ secs and reviewing it each time, doing guess work on what direction the object will move with which key.

[scotty38]

Apart from anything else you can move your mount with the laptop if you’re using sharp cap etc with ascom drivers. As said though you can get it done via cdc which is free too and shouldn’t need to do it manually at all.

[Richard Wesson]

18 minutes ago, Quetzalcoatl72 said:

I've never heard of cdc, is it freeware and what does it do and how do I clear my alignment points? It's very hard making fine adjustments while holding the mount etc, I'm used to the handset, aligning with the directional keys and the pressing esc and holding esc to re-align. My main camera is a dslr so I can't see the exposure live otherwise I'd align on the object I want to image. I have to keep taking 30+ secs and reviewing it each time, doing guess work on what direction the object will move with which key.

You should try plate solving - I use it in APT with my dslr. Saves so much time and hassle when aligning on an image.

CdC or Cartes du Ciel is a free planetarium bit of software. Integrate better with eqmod than stellarium. 

[Richard Wesson]

Link to CdC download here:

https://sourceforge.net/projects/skychart/

 

[Quetzalcoatl72]

30 minutes ago, Richard Wesson said:

You should try plate solving - I use it in APT with my dslr. Saves so much time and hassle when aligning on an image.

CdC or Cartes du Ciel is a free planetarium bit of software. Integrate better with eqmod than stellarium. 

I'd forgotten about plate solving, something I need to look into thanks. In other news my rowan belt mod kit should arrive tomorrow so hopefully I can get that installed and have smoother slewing and tracking!

[JSeaman]

As you will have seen CDC = Cartes Du Ciel, works with EQMod to let you control the mount from a PC

What adjustments are you making by hand? EQMod will do slewing for you and yes it's free.

Do you have live view on the camera? In fact, what camera is it?

A finder scope might be a worthy investment to save you a lot of time. 

Agree on the plate solving recommendation too, that's a real time saver - take a picture of the sky, plate solve and it tells you where you are actually pointing so you can correct it

[almcl]

Couple of other points which I don't think anyone has mentioned.

Once you calibrate and before moving to target, carry out a guiding assistant run and accept its recommendations.  This will account for changes in seeing and may make other suggestions.  I can't see one in your log file?

Second, and this may not be what you want to hear, but you appear to be imaging at around 0.5" per pixel (making assumptions about your DSLR and scope)  but guiding at over 6 " per pixel, a ratio of 12 to 1.  This is likely to be problematic, even if you can get the guiding down to a tenth of a pixel - which PHD developers suggest is the likely limit of possible accuracy.  In the fullness of time you may need to consider an Off Axis Guider, although that too will not be without its challenges.

[Quetzalcoatl72]

1 hour ago, JSeaman said:

As you will have seen CDC = Cartes Du Ciel, works with EQMod to let you control the mount from a PC

What adjustments are you making by hand? EQMod will do slewing for you and yes it's free.

Do you have live view on the camera? In fact, what camera is it?

A finder scope might be a worthy investment to save you a lot of time. 

Agree on the plate solving recommendation too, that's a real time saver - take a picture of the sky, plate solve and it tells you where you are actually pointing so you can correct it

I have a finderscope that's how I'm guiding, unless you mean a secondary one? I'm using a canon 600d it has x5 x10 zoom. I just unlock the clutches to move bright star into position, the only adjustments I make, unless I don't like a galaxy or nebula's position I may rotate the camera.

[Quetzalcoatl72]

1 hour ago, almcl said:

Couple of other points which I don't think anyone has mentioned.

Once you calibrate and before moving to target, carry out a guiding assistant run and accept its recommendations.  This will account for changes in seeing and may make other suggestions.  I can't see one in your log file?

Second, and this may not be what you want to hear, but you appear to be imaging at around 0.5" per pixel (making assumptions about your DSLR and scope)  but guiding at over 6 " per pixel, a ratio of 12 to 1.  This is likely to be problematic, even if you can get the guiding down to a tenth of a pixel - which PHD developers suggest is the likely limit of possible accuracy.  In the fullness of time you may need to consider an Off Axis Guider, although that too will not be without its challenges.

No I've never used the assistant. very soon I will be swapping out the dslr for a dedicated CCD cam, so in the upcoming months I'll be using a ZWO ASI 533MC-PRO, or something along those lines. I've never used a ccd for deep sky objects so that's another challenge ahead I was to resolve before I even get the new camera. Could practice on the 120asi i guess, but then i wont be guiding

Edited April 26, 2021 by Quetzalcoatl72

[Richard Wesson]

17 hours ago, Quetzalcoatl72 said:

I'd forgotten about plate solving, something I need to look into thanks. In other news my rowan belt mod kit should arrive tomorrow so hopefully I can get that installed and have smoother slewing and tracking!

I would really recommend it. I used to struggle with trying to find a target in the light polluted skies here, then lining it up in the frame properly which could take ages. In APT  (https://www.astrophotography.app/) I normally (following polar alignment in Sharpcap) select an object and use go to ++ which directs it roughly  into the correct place and then uses plate solving to accurately place it in the centre of view. I also connect PhD to APT to allow dithering and use it to control my imaging runs. 

[JSeaman]

On 26/04/2021 at 23:45, Quetzalcoatl72 said:

I have a finderscope that's how I'm guiding, unless you mean a secondary one? I'm using a canon 600d it has x5 x10 zoom. I just unlock the clutches to move bright star into position, the only adjustments I make, unless I don't like a galaxy or nebula's position I may rotate the camera.

600D has live view doesn't it? You should be able to put that on and move the mount around

If you're using the finderscope for guiding then you could pop the guide camera off so you can use it to set the initial position easily without the need to plate solve

So essentially you would:

1. Slew to a target with Live View

2. Set up guiding calibration

3. Start guiding

4. Not touch anything

5. Take pics

 

If you neeed to rotate the camera, pause guiding, rotate camera, go to step 3

[Quetzalcoatl72]

2 hours ago, JSeaman said:

600D has live view doesn't it? You should be able to put that on and move the mount around

I bought a zwo asi533 cam last night so i wont be using the dslr anymore

[newbie alert]

On 26/04/2021 at 23:45, Quetzalcoatl72 said:

I have a finderscope that's how I'm guiding, unless you mean a secondary one? I'm using a canon 600d it has x5 x10 zoom. I just unlock the clutches to move bright star into position, the only adjustments I make, unless I don't like a galaxy or nebula's position I may rotate the camera.

If you unlock the clutches you've now lost your star alignment so your mount now hasn't got a clue where it is.. really bad habit to do.. why not move it on the handset?? Or the on-screen handset..

[newbie alert]

I'd also run the guiding assistant and apply the settings.. and rotate the camera so it's orthogonal.. are you pulse guiding or st4?

[michael8554]

From your GuideLog:

You should Calibrate at Dec=0, not Dec = 38, Dec = 41, etc.

PHD2 has been told your guide image scale is 6.45arcsec/pixel.

I calculate it to be 3.27arcsec/pixel, so you have a wrong entry somewhere.

(I notice you did the first Calibration with Guide Rate at 1.5arcsec/sec, but you corrected that for subsequent Cals. )

So Cal on later runs is taking about 30 steps instead of about 12.

Colour guidecam is struggling, many Star Lost situations.

So get your image scale and Calibrations right, do  a Guide Assistant run on Target, to set Minimum Moves and Dec Backlash Compensation.

Then post the GuideLog.

You don't seem to have read any PHD2 instructions, there are plenty of Help and How To guides in the Help menu.

Start with this one:

https://openphdguiding.org/phd2-best-practices/

Michael

 

 

[JSeaman]

2x2 binning hence the 6.45

[michael8554]

Ah darn it, missed that !

I'd stick with 3.27, except the colour scope will struggle even more.

But 30 steps to Calibrate means something isn't right, maybe EQASCOM guide rate ?

Michael

 

 

[Quetzalcoatl72]

9 hours ago, newbie alert said:

I'd also run the guiding assistant and apply the settings.. and rotate the camera so it's orthogonal.. are you pulse guiding or st4?

I'm pulse guiding, and I've always been told after the first star align you do the clutches then the hand set. Then on the 2nd star you just do the hand set and you're done. But now that I started using all of these programs and not the hand set things are surely different. Surely just centering an object with the handset wont keep the mount's go-to perfect and always centered when i go to different objects throughout the night, I've heard I need to plate solve.

[Quetzalcoatl72]

4 hours ago, michael8554 said:

Ah darn it, missed that !

I'd stick with 3.27, except the colour scope will struggle even more.

But 30 steps to Calibrate means something isn't right, maybe EQASCOM guide rate ?

Michael

 

 

I've recently applied the eq6 rowan belt mod to my mount and it sounds much better, I have no idea how it will function next time. Tomorrow seems clear so I'm going to redo everything and see what happens.