Hardware and software advice needed for upgrading to guided imaging

[ianpwilliams]

I don't have a mains adaptor, but it all has to be battery powered anyway. I'll check the power settings for the camera and see if I have better luck next time.

[ianpwilliams]

I have everything running again. I ran StellariumScope, clicked Connect which brought up EQMOD, ran Stellarium, went into settings and deleted three telescopes, leaving the connected ones.

When I slew using EQMOD it works, particularly if I set the slew speed to the maximum of 4.

In Stellarium I can see the "Scope" crosshair. Incidentally would I set that crosshair position manually if outside, maybe to whatever I could see in APT? I know in theory the scope should be pointing at Polaris once polar aligned, but I'm not sure if that would be exactly true or not.

Anyway, when I select another nearby target in Stellarium, it does seem to be slewing but really slowly, even if EQMOD slew speed is set to 4 (not sure if that makes a difference anyway though). Is there any way I can speed it up?

[ianpwilliams]

Ignore my previous question, it was because I had Sync selected instead if Scope. Although my Polaris question still stands.

[Tinker1947]

So its working then.....??

[D4N]

It would be close to Polaris if Dec is at 90N, remember that Polaris isn't exactly on the North celestial pole.

I imagine that there is a max slew speed in there somewhere, I use CdC though so not so sure about Stellarium.

/Dan

Sent from my iPad using Tapatalk

[Tinker1947]

My Stellarium slew speed may be a bit slower than EQMod but not by much, the speed set in EQMod doesn't appear to alter it......

[ianpwilliams]

Yes it does all seem to be working now. If I choose a target in Stellarium and tell Stellarium to slew the telescope to it then it does it! Amazing stuff!

So now I'm trying to get polar alignment working using EQMOD, based on the YouTube tutorial. These seem to be the steps that I need to follow:

Run StellariumScope

Click connect (which opens EQMOD)

Minimize StellariumScope

Click "Unpark Scope" in EQMOD

Expand the EQMOD window

Uncheck "Enable Limits"

Click "Pole Star HA" button

Select 12 o'clock from pulldown menu

Unlock the Dec on the mount and put the scope side-on and remove the polarscope caps

Remove the scope and weights?

Use the Alt and Az bolts to centre Polaris on crosshairs on Polarscope

Use the Alt bolt to move Polaris to top of big circle (12 o' clock position)

Use the left and right Slew controls in EQMOD to rotate the RA until the small circle in the polarscope is over Polaris at 12 o'clock

Click "Set Polarscope home"?

Click Align Polarscope in EQMOD - this will rotate the RA until the small circle is where Polaris should actually be

Use the Alt and Az bolts to move Polaris to the small circle in the polarscope

Park the scope to the HOME position

Re-enable Limits in EQMOD

A few questions...

1 - Do these steps look right?

2 - Do I need to remove the scope and weights? The YouTube tutorial suggested possibly removing the scope, which surely would also mean removing the weights to avoid slewing with weights and no scope. So do I need to remove both, or neither? Will it really get into such an odd position?

3 - The time is wrong in EQMOD, despite being correct in Windows (5pm in EQMOD was 4:03pm in Windows), and I can't see a way to change it. At the moment I have 55.96N, 3.14W, 21m elevation, and just the time seems to be wrong.

4 - Using "Set Polarscope Home" (and then "Return to Home" later) - is this worth doing? If I'm setting up every time then I'm not sure if it would be worth having a saved position. Surely it would be hard to be that precise setting up next time?

5 - In Stellarium I'm not convinced that the latitude and longitude were correct either. I seem to recall reading something about how you have to convert them to a different format or something, is that correct?

[Tinker1947]

I can't help with the PA, i use the handset with the PA option, then reconnect EQMod ect afterwards......

[ianpwilliams]

Yeah I could just polar align the old fashioned way using the slew controls in EQMOD and the EQMOD polar alignment window, and by looking through the polarscope. But the method in the YouTube video appears to be more accurate as far as I can tell.

[ianpwilliams]

I can't help but think that I should have tried upgrading to guided imaging in the autumn. I can do all the practice I want indoors, but when I eventually get out there in the freezing cold it's not going to be pretty!

[ianpwilliams]

A few questions about PHD2 and the guide camera now:

I loaded up PHD2 and connected to the mount and camera, and that all worked fine (PHD2 opened EQMOD - would it do that if Stellarium had already opened EQMOD previously?).

As you can see from the attached image (taken indoors while looping a 0.01 second exposure because it's in a bright room), there are a couple of dots in the image - will that be dust or something do you think? Possibly on the guide scope lens? And will it be a problem?

The guide camera instructions say to insert the guide camera halfway into the guide scope, tighten the three setscrews, and then loosen one of them to allow movement of the camera in and out of the guide scope in order to achieve focus, either on a star or a distant object. Will it be worth trying to focus on a distant object indoors in the daytime do you think? I do have another room which I could move the setup into, but it'll be a pain moving it all through. But it's either that or I do it outside. Either way I'm aware that I'll have to then do finer focus by rotating the objective lens on the guide scope, and I'm guessing that I'll have to do that outside.

[D4N]

Why not just take the guide scope to the other room? It doesn't need to be attached to everything else just to sort the focus out.

/Dan

Sent from my iPad using Tapatalk

[ianpwilliams]

Yes there is that option I suppose

[ianpwilliams]

A few questions about PHD2 and the guide camera now:

I loaded up PHD2 and connected to the mount and camera, and that all worked fine (PHD2 opened EQMOD - would it do that if Stellarium had already opened EQMOD previously?).

As you can see from the attached image (taken indoors while looping a 0.01 second exposure because it's in a bright room), there are a couple of dots in the image - will that be dust or something do you think? Possibly on the guide scope lens? And will it be a problem?

The guide camera instructions say to insert the guide camera halfway into the guide scope, tighten the three setscrews, and then loosen one of them to allow movement of the camera in and out of the guide scope in order to achieve focus, either on a star or a distant object. Will it be worth trying to focus on a distant object indoors in the daytime do you think? I do have another room which I could move the setup into, but it'll be a pain moving it all through. But it's either that or I do it outside. Either way I'm aware that I'll have to then do finer focus by rotating the objective lens on the guide scope, and I'm guessing that I'll have to do that outside.

Is there anyone who can help with the above?

[ianpwilliams]

A few questions about PHD2 and the guide camera now:

I loaded up PHD2 and connected to the mount and camera, and that all worked fine (PHD2 opened EQMOD - would it do that if Stellarium had already opened EQMOD previously?).

As you can see from the attached image (taken indoors while looping a 0.01 second exposure because it's in a bright room), there are a couple of dots in the image - will that be dust or something do you think? Possibly on the guide scope lens? And will it be a problem?

The guide camera instructions say to insert the guide camera halfway into the guide scope, tighten the three setscrews, and then loosen one of them to allow movement of the camera in and out of the guide scope in order to achieve focus, either on a star or a distant object. Will it be worth trying to focus on a distant object indoors in the daytime do you think? I do have another room which I could move the setup into, but it'll be a pain moving it all through. But it's either that or I do it outside. Either way I'm aware that I'll have to then do finer focus by rotating the objective lens on the guide scope, and I'm guessing that I'll have to do that outside.

And this too?

[Thalestris24]

Hi

Looks like you have some dust bunnies or marks on the camera glass but I wouldn't worry about them. Presumably you can just detach the finder guider and get approximate focus on a distant object at your convenience. You can then get better focus outside on stars with everything set up. Once you've done that you shouldn't have to do it again. You can't really use PHD2 to focus during the day since it doesn't let you do short enough exposures. The Altair capture program does let you go down to ms so you can use that during the day.

Louise

[ianpwilliams]

Yes it does all seem to be working now. If I choose a target in Stellarium and tell Stellarium to slew the telescope to it then it does it! Amazing stuff!

So now I'm trying to get polar alignment working using EQMOD, based on the YouTube tutorial. These seem to be the steps that I need to follow:

Run StellariumScope

Click connect (which opens EQMOD)

Minimize StellariumScope

Click "Unpark Scope" in EQMOD

Expand the EQMOD window

Uncheck "Enable Limits"

Click "Pole Star HA" button

Select 12 o'clock from pulldown menu

Unlock the Dec on the mount and put the scope side-on and remove the polarscope caps

Remove the scope and weights?

Use the Alt and Az bolts to centre Polaris on crosshairs on Polarscope

Use the Alt bolt to move Polaris to top of big circle (12 o' clock position)

Use the left and right Slew controls in EQMOD to rotate the RA until the small circle in the polarscope is over Polaris at 12 o'clock

Click "Set Polarscope home"?

Click Align Polarscope in EQMOD - this will rotate the RA until the small circle is where Polaris should actually be

Use the Alt and Az bolts to move Polaris to the small circle in the polarscope

Park the scope to the HOME position

Re-enable Limits in EQMOD

A few questions...

1 - Do these steps look right?

2 - Do I need to remove the scope and weights? The YouTube tutorial suggested possibly removing the scope, which surely would also mean removing the weights to avoid slewing with weights and no scope. So do I need to remove both, or neither? Will it really get into such an odd position?

3 - The time is wrong in EQMOD, despite being correct in Windows (5pm in EQMOD was 4:03pm in Windows), and I can't see a way to change it. At the moment I have 55.96N, 3.14W, 21m elevation, and just the time seems to be wrong.

4 - Using "Set Polarscope Home" (and then "Return to Home" later) - is this worth doing? If I'm setting up every time then I'm not sure if it would be worth having a saved position. Surely it would be hard to be that precise setting up next time?

5 - In Stellarium I'm not convinced that the latitude and longitude were correct either. I seem to recall reading something about how you have to convert them to a different format or something, is that correct?

Thanks. I'll remove the guidescope to get focus in the other room. I'll check to see if the dust bunnies are on the guidescope or guide camera. I have a lens pen but I can't remember if that's for removing dust bunnies. But I can always leave them.

I still have the above questions outstanding if anyone can help.

Clear skies forecast here tonight except for an orange block at 8pm. I wonder if it might be worth getting out there...not that I would expect to end up with anything, as I'm sure there will be unexpected issues.

Just remembered another question. If and when I do actually get outside and get to the imaging stage, what kind of sub length should I try? For centering the target I would probably do the usual 30 secs, but what about subs? Should I start low and increase, maybe 1min, 2min etc until I get star trails, and then go back one?

[wxsatuser]

Sub lemgth is easy with a dslr.

The correct length for your sky brightness is when the camera histogram peak reachs at least 20% but no more than 40%.

Does'nt matter what other settings you have, iso etc, just expose for around at least 20%.

Depending on sky brightness this could be 30secs or 10minutes, or more.

You will have to do test exposures to find your optimum exposure.

I would suggest taking a 30sec exposure and see where the histogram peak lies.

For example if it lies at say 10% you could double it to 1minute and it will be near 20%

I normally as a rule expose to 25%.

Here is the histogram on my 60Da, a 10minute exposure for around 25%, this was with an LP clip filter.

We are looking at the white luminance one at the bottom, ignore the RGB ones.

[ianpwilliams]

So what is it that will limit my sub length? Star trails (which presumably there would still be a risk of even when guiding?) or histogram, or both? There has to be something that limits it, otherwise you could go for hours weather permitting.

And you say that the ISO won't matter (I usually always go 800)?

And regarding the histogram, the white luminance peak looks hard left to me, shouldn't it be around the first line to the right to be 25%?

Also, do you know if APT provides a histogram after a shot is taken? I'm guessing it would. I could forget about APT altogether and use the camera screen and remote timer, but it seems like APT would be worth trying.

[wxsatuser]

The white histogram is just past the first line, 20% on Canons.

What limits you exposure is sky brightness, tracking and how much noise you camera is going to generate.

It's a balancing act between these main three.

With an HEQ5 Pro you should easily do guided exposures to 10minutes, with good PA but if you have lots of LP

then you may not get past 1 or 2 minutes. If you have LP get a decent filter like an Astronomik clip filter as a filter

will allow you to expose longer, upto 3times longer.

Whatever you do do not expose to the right, you will here this around the net but don't do it.

[wxsatuser]

Forgot, ISO.

Whatever ISO you use just expose for around that first line.

As you lower the ISO you will expose longer but keep that peak at 20%ish.

800 is most likely fine for all objects.

[ianpwilliams]

Damn, that's a worry. I was already getting 1 min subs unguided, so I hope I haven't wasted the extra money buying the guided equipment just to up it to 2 mins or something!

Astrononik website says this:

I want to take astronomic pictures, but the night sky is bright due to light pollution. How can I improve my results using a DSLR?

We would suggest two filters: (1) The CLS-filter enhances the contrast and allows you to have a 5x longer exposure time. The background stays neutral and allows fine corrections during the post processing. (2) If you take pictures of HII regions we suggest an Astronomik h-alpha filter with a FWHM (full width at half maximum) of 12nm. The gain in contrast is extreme and it's no problem to expose through the whole night. This offers you the possibility to take pictures with an amazing depth. The disadvantage of the filter: A full moon isn't a reason anymore to quit and go to sleep

FLO also have light pollution filters (also very expensive though), would they be an alternative option?

[wxsatuser]

One minute subs but where was the histogram?

IMO if you going to get a filter, get a good one.

If you unmodded get a CLS clip, I would'nt personally go for the Ha one.

I do also have the Hutech IDAS 2 inch one, this  you will have to fit in your imaging train somewhere.

[wxsatuser]

To give you an idea here is M27 with a 200mm lens taken through the huge glow of the local ffootball club floodlights.

I could'nt see many stars, just the very bright ones.

At my usual ISO my subs are easily 5minutes but the glow pushed the M27 subs down to 2minutes for the same 25% histogram.

[Pompey Monkey]

Damn, that's a worry. I was already getting 1 min subs unguided, so I hope I haven't wasted the extra money buying the guided equipment just to up it to 2 mins or something!

Astrononik website says this:

I want to take astronomic pictures, but the night sky is bright due to light pollution. How can I improve my results using a DSLR?

We would suggest two filters: (1) The CLS-filter enhances the contrast and allows you to have a 5x longer exposure time. The background stays neutral and allows fine corrections during the post processing. (2) If you take pictures of HII regions we suggest an Astronomik h-alpha filter with a FWHM (full width at half maximum) of 12nm. The gain in contrast is extreme and it's no problem to expose through the whole night. This offers you the possibility to take pictures with an amazing depth. The disadvantage of the filter: A full moon isn't a reason anymore to quit and go to sleep

FLO also have light pollution filters (also very expensive though), would they be an alternative option?

The Astronomic CLS LP filter works very well. I could do 7-8 minute exposures from my bright suburban home skies.

The clip-in version is the easy option, but it only clips into the DSLR, making it redundant if you go down the CCD route in the future.