Not fully understanding Polar Alignment

[masjstovel]

Hi,

I'm a newbie and I've used a fair amount of hours on the web studying polar alignment now. I thought i had it after 30 minutes, but now several hours later i understand less than i did then.

I have the EQ5-mount and the "new" sky-watcher polar alignment reticule, which represents a clock, but no Northern hemisphere constallations. I get the Polaris position from an app. It gives me a visual position in the clockwheel simular to the one in my polar scope. It also displays the Polaris position digitally (i.e. 01:37, which corresponds to the visual position on the clock). It gives me my local longitude (5* 15'E). Lastly it gives me the local time.

From what i understand the "old" Polar reticules doesn't have the clock, but a small dot or circle on the bigger circle with constallations around it like the big dipper that you align visually with the actual big dipper, then align Polaris in the small circle?

1. The Polar alignment scope i have has a white marker line on it (Index marker ring). What do i use this for, and should it point in the 12'oclock position or do i turn on this at some time?

2. When i rotate the RA axis, the polar clock also rotate. Are the 6 o'clock position always supposed to point straight down, and 12 o'clock position always supposed to point straight up when i polar align or do i have to rotate the clock in relation to my position (longitude) or something? Like, do i have to calibrate the clockwheel orientation at any time to get accurate alignment or does always 6 point straight down like an actual clock? I dont mean calibrating to make the reticule calibrated by this, but turning around the clock reticule so that 6 o'clock is no longer in the 6 o'clock position.

3. Do i have to take in consideration that the view in the polar alignment scope is upside-down, or do i Place polaris identically like on the app? (SAM console is the app, and i downloaded it for my Sky-watcher adventurer mini).

4. The videos and articles i've read on this type of reticle also provides you a HA (Hour angle). Is the new reticle just a clock showing this HA? Or do I have to take HA in consideration in addition to aligning or is this polar clock really just showing the HA visually?

5. Some articles (this for instance: https://lonewolfonline.net/polar-alignment-equatorial-telescope-mount/

says that its important to know what date and time of the year the Polaris is at its highest altitude. Why is this important?

6. Videos and articles mentions that putting my telescope in "Home position" is important. Why is this? The polar alignment Scope is pointing the same way no matter where the telescope points.

7. As mentioned the app provides my local longitude. Is this important in the alignment process other than "Nice to know"?

I welcome any answers!

 

[Robny]

Try not to overthink the process too much...

So long as the mount is levelled, the polar scope is aligned (centred in the housing) and your time, date and location is correct in the app you are good to go. 

You need to rotate your DEC axis so you can see through the polar scope, then to make it a little easier rotate the RA axis so 12:00 is at the top of the polar scope.  You can get this by aligning Polaris onto the cross hairs in the centre of the scope then using the altitude bolts, place Polaris directly above centre where 12 would be then, then rotate RA until 12 is sitting on top of Polaris.

Once this is done, look at your app and using the altitude and azimuth bolts place the star in the polar scope in the same position to match the app, then you're done.

You can use the setting circles (I never have), but it is quite convoluted in my opinion...However, it would be a good skill to learn in case you are out with no signal and cannot use the app.  But the above should get you going, this was my method until I started using Sharpcap PRO to polar align - GAME CHANGER 

Hope this makes sense?

Good Luck

Rob

[masjstovel]

Hi Rob, and thanks for the reply. The process you describe is what i have done.

I installed synscan goto upgrade kit a week ago ish, and when i do the 2-star align, is when the problems happen. The first star it goes to is pretty close, but needs small adjustments to center it. Ive chosen Vega then in east. Then when i goto the next star left again. Dont remember the name. The scope then goes haywire and points down in the ground almost. Guessing 30degrees off or something. 

Soo i figured i did something wrong with the alignment process. Thats why i started with all these videos and did, as you describe, overthink it.

But now i dont know what is the problem.

I can also mention that the scope bumps in the tripod legs sometimes when the synscan goes to a position. I look out for this and stop it but. Is there a way to programthe mount to go another way or something to avoid this?

 

What is sharpcap pro?

[Cornelius Varley]

5 minutes ago, masjstovel said:

Hi Rob, and thanks for the reply. The process you describe is what i have done.

I installed synscan goto upgrade kit a week ago ish, and when i do the 2-star align, is when the problems happen. The first star it goes to is pretty close, but needs small adjustments to center it. Ive chosen Vega then in east. Then when i goto the next star left again. Dont remember the name. The scope then goes haywire and points down in the ground almost. Guessing 30degrees off or something. 

Soo i figured i did something wrong with the alignment process. Thats why i started with all these videos and did, as you describe, overthink it.

But now i dont know what is the problem.

I can also mention that the scope bumps in the tripod legs sometimes when the synscan goes to a position. I look out for this and stop it but. Is there a way to programthe mount to go another way or something to avoid this?

 

What is sharpcap pro?

Your problem seems more related to a power problem and not polar alignment. What are you using to power the mount ?
Sharpcap Pro is an image capture programme that has a polar alignment routine.

[masjstovel]

The synscan says 12v, so i have an adaptor with the correct 2.5mm pin and adjustable volt which i set to 12 and put it in the wall? Is this wrong?

Ill look into sharocap.

[Cornelius Varley]

24 minutes ago, masjstovel said:

The synscan says 12v, so i have an adaptor with the correct 2.5mm pin and adjustable volt which i set to 12 and put it in the wall? Is this wrong?

Ill look into sharocap.

What is the amp output of the PSU? Does the PSU have a regulated output ? Non regulated PSU's are not recommended because they can't provide a stable voltage output under load. What happens is that when ta non regulated PSU is placed under load, ie when slewing, it can't maintain a constant 12v and amps so the PSU drops the voltage output and increases the amps to compensate. When this occurs the voltage will drop below that required for the Synscan unit to operate correctly. The mount will then start slewing wildly. 
The power supply pin size on Synscan mounts is 2.1mm not 2.5mm so you might also get intermittent problems there too.

[masjstovel]

 

I meant 2.1mm, or it fits perfectly.
I Attached a photo. Norwegian electric systems use 240V. I see its separated in PRI (priority) 240V 0.7A and SEC (secondary) 12V, 1.5A, so i guess i have 0.7A then since i plug it in the wall?
I'm not into electrinics, but maybe you understand it better? 

[Anvil Basher]

I read somewhere that if you put the motor on backwards it does as is happening to you. The same goto upgrade also fits the eq2/3?, but the motors are fitted opposite, but fits both mounts. Make sure the box you got has the correct eq mount it is for.

[Cornelius Varley]

The maximum amps output on the PSU is a little low. Skywatcher usually recommend a PSU with an output of 2 amps min 11-15v

[Cornelius Varley]

27 minutes ago, Anvil Basher said:

I read somewhere that if you put the motor on backwards it does as is happening to you. The same goto upgrade also fits the eq2/3?, but the motors are fitted opposite, but fits both mounts. Make sure the box you got has the correct eq mount it is for.

The two upgrade kits share the same box but are completely different. The motors cannot be put on backwards, they only fit one way. The gears can be accidently fitted the wrong way but that would also mean that the mount would not have slewed towards the first alignment star correctly.

[masjstovel]

52 minutes ago, Anvil Basher said:

I read somewhere that if you put the motor on backwards it does as is happening to you. The same goto upgrade also fits the eq2/3?, but the motors are fitted opposite, but fits both mounts. Make sure the box you got has the correct eq mount it is for.

The Box had the EQ5-sticker, and its the parts to the EQ5, im pretty sure.

When Scope is parked, the RA-cogs are on the left side and DEC-cogs are on the lower side. 
On the Picture that will be RA-cogs to the right as you view the Picture, and DEC cogs on the lower side.

Thats correct right?

 

29 minutes ago, Cornelius Varley said:

The maximum amps output on the PSU is a little low. Skywatcher usually recommend a PSU with an output of 2 amps min 11-15v

Ok, So you think this is the problem? Any recommandations what adaptor to get? IMO its stupid that an adaptor with a socket to put in the wall didnt include in the box, but i dont know.. Only the 12v car-socket.

[OJ87]

1 hour ago, masjstovel said:

 

I meant 2.1mm, or it fits perfectly.
I Attached a photo. Norwegian electric systems use 240V. I see its separated in PRI (priority) 240V 0.7A and SEC (secondary) 12V, 1.5A, so i guess i have 0.7A then since i plug it in the wall?
I'm not into electrinics, but maybe you understand it better? 

Hi Masjstovel, as I see in photo, your output is 1.5A when you use 12V, if it's enough or not, you must check your manual and see what S/W recommends. For my EQ6R is not enough, it requires at least 2,5A in tracking mode and 4A when I use goto. 

 

[masjstovel]

3 minutes ago, OJ87 said:

Hi Masjstovel, as I see in photo, your output is 1.5A when you use 12V, if it's enough or not, you must check your manual and see what S/W recommends. For my EQ6R is not enough, it requires at least 2,5A in tracking mode and 4A when I use goto. 

 

Hi, and thanks for the reply.
This is what the manual says, but im blank on electronics so im not sure what it means? 
 

PC Connection -  RS-232C, 9600bps, No parity check, 8 data bits, 1 start bit, 1 stop bit

Power Supply -  DC 7.5 to 12V, 100mA

Power output on Multi-purpose port - Power Supply Voltage - 0.7V Maximum 100mA current output

 

[Cornelius Varley]

13 minutes ago, masjstovel said:

Hi, and thanks for the reply.
This is what the manual says, but im blank on electronics so im not sure what it means? 
 

Power Supply -  DC 7.5 to 12V, 100mA

 

This relates to the recommended voltage for powering the handset for firmware updating. The full Synscan manual usually recommends a regulated PSU 11-15vDC  2 amps minimum. 

[masjstovel]

6 minutes ago, Cornelius Varley said:

This relates to the recommended voltage for powering the handset for firmware updating. The full Synscan manual usually recommends a regulated PSU 11-15vDC  2 amps minimum. 

Thanks again! 2A minimum, is there a max Amp? found one 12V 5A

[Cornelius Varley]

Just now, masjstovel said:

Thanks again! 2A minimum, is there a max Amp? found one 12V 5A

So long as the mount doesn't require more than the max amps that the PSU can supply then it should be ok. The mount will only pull the amount of amps it needs.

[malc-c]

Back in 2011 I measured the current draw of my EQ-5 synscan.  

 

So your 5A power supply should be fine.  There is no maximum.  If you used a 20A supply the mount will still draw 1.8A.  You'll just have more head room and the PSU won't brake a sweat supplying what the mount needs.

Quote

When slewing my 200P on an EQ-5 the actual current draw is around 1.8A when both axis are moving at the same time, and just over an amp when slewing just the RA.

12v 2A would be the minimum I would recommend for the EQ mounts - I'm using a 2A switching supply that came with a now defunct network switch which works fine

Edit: just re-checked and the SynScan manual states 12v 2 Amp minimum continuous current rating for the mains power supply [/quote]

So your 5A power supply should be fine.  There is no maximum.  If you used a 20A supply the mount will still draw 1.8A.  You'll just have more head room and the PSU won't brake a sweat supplying what the mount needs.

Edited April 27, 2019 by malc-c

[masjstovel]

Update: The 12V 5A i found was for ordering only, so i bought  a 12V 2.5A instead. 
Also i learned how to park the Scope. It seems important, since the scope doesn't "know" where its pointing at startup right? I must have been close to having it parked the last time though because my first star in alignment the last time, Vega, was pretty close.

So, today its cloudy (of course), but i made a plan for testing it tonight. 

Since i know that Polaris is at 60* 25', and North, I can set up the mount (& scope) pointing at least pretty close to where Polaris is behind the clouds right? Tripod leveled and all that. Then calibrate these setting-circles on RA and DEC axis. Pointing like this on polaris its supposed to be RA: 6 o'clock, and DEC 90degrees, or is it something I've misunderstood? Then I plan to start the 2 or 3 star alignment, and use Stellarium to read of the positions when its finished slewing and check if the setting circles match.

This plan would work even if its cloudy wouldn't it? I'm kind of high on myself now for the first time since I bought the scope, so please don't slaughter the plan  

I mean, if i missed Polaris a bit, it would still be relatively correct on the setting circles wouldn't it?
 

 

Edited April 27, 2019 by masjstovel
Typo

[Anvil Basher]

On 26/04/2019 at 17:35, masjstovel said:

The Box had the EQ5-sticker, and its the parts to the EQ5, im pretty sure.

When Scope is parked, the RA-cogs are on the left side and DEC-cogs are on the lower side. 
On the Picture that will be RA-cogs to the right as you view the Picture, and DEC cogs on the lower side.

Thats correct right?

 

Ok, So you think this is the problem? Any recommandations what adaptor to get? IMO its stupid that an adaptor with a socket to put in the wall didnt include in the box, but i dont know.. Only the 12v car-socket.

 

If the system is moving correctly with the handset then it must be your polar alignment. If this odd movement is only when using goto, but the hand controls work fine, it leaves your alignment. The psu at 5 amp is good. The psu you have currently might be under pressure, but if it is working the hand control on the pad fine then I would have thought that if the power being drawn was not enough using goto, it would slow down, maybe stop, maybe start smoking, spark........but not speed up and go in all directions. Maybe if the counterweights were off balance it may affect it, but I guess you have correctly balanced the mount. Maybe it is the psu, but my experience of psu's leaves me thinking if it does not supply enough power then the equipment normally does not work, slows, or starts smoking through seizure.

[Erling G-P]

If the mount continues to point the scope in odd directions, you could also try doing a factory reset; available somewhere in the menus.  It helped me when I had a similar issue with my HEQ5 - it would slew to positions way off the alignment stars, for no apparent reason.  Factory reset brought it back to normal.

[masjstovel]

@Anvil Basher I just dont understand that the alignment is so off given that @Robny's procedure is correct. That's what ive done every time, and feel quite satisfied that im on the right place.

With that said, i got this Mel/Maz message last time, and i don't know what would be acceptable Levels of Mel/Maz error?

The other photos are the setup in what i believe to be the home position. Does it look correct? 

I havent though about it before, but it may be important:
When press the slew buttons from parked position this happens:

Right key: RA sends the Scope to the left

Left key: RA sends the Scope to the right

Up key: DEC sends Scope to left

Down key: DEC sends Scope to right

 

Is this correct???

I also wonder about something on the dec axis. It seems a bit off topic, but there is a thought behind it. Lets say i dismounted the telescope, turned it 180 degrees and mounted it again. Would that have anything to say synscan-wise other then id have to redo the alignment and all? Is there a right and wrong way to mount the scope? I mean right is right and left is left on this axis no matter what, isnt it? I ask because at 60 degrees latitude the RA-motor cover and the DEC cover would "crash" if i want to observe something near the Northern horizon. Is this just how it is or am i far down in a hole with something here?
 

Edited April 27, 2019 by masjstovel

[masjstovel]

7 minutes ago, Erling G-P said:

If the mount continues to point the scope in odd directions, you could also try doing a factory reset; available somewhere in the menus.  It helped me when I had a similar issue with my HEQ5 - it would slew to positions way off the alignment stars, for no apparent reason.  Factory reset brought it back to normal.

Thanks for the tip. If it turns out i have done both the polar alignment and the motor installation correct, i will try that! Would i have to reinstall the newest firmware then or is it kept with a factory reset?

Edited April 27, 2019 by masjstovel

[Erling G-P]

3 minutes ago, masjstovel said:

Thanks for the tip. If it turns out i have done both the polar alignment and the motor installation correct, i will try that! Would i have to reinstall the newest firmware then or is it kept with a factory reset?

I'm pretty certain the firmware isn't affected, but you'll have to input lat/longitude and other basic info again.

 

Your Mel/Maz values are considerably higher than what I normally see - I normally am below 10' on each axis, going close to or below 0' on a few rare occations. As a newbie myself however, I'm not sure what they're supposed to be, or what is considered good or 'good enough'.

[Anvil Basher]

9 minutes ago, masjstovel said:

Thanks for the tip. If it turns out i have done both the polar alignment and the motor installation correct, i will try that! Would i have to reinstall the newest firmware then or is it kept with a factory reset?

It does sound like an issue with alignment. North leg on tripod facing north, get your polar alignment, sycset requires location, time, etc, and it should work. The part about the hand control working was just to see if it moved in every direction perfectly, showing it has enough power to move them. It is as if you are aligning from the south, especially as the scope points towards earth when looking at a star you can see in the sky from the north. A factory reset might just do it.

[masjstovel]

5 minutes ago, Erling G-P said:

I'm pretty certain the firmware isn't affected, but you'll have to input lat/longitude and other basic info again.

 

Your Mel/Maz values are considerably higher than what I normally see - I normally am below 10' on each axis, going close to or below 0' on a few rare occations. As a newbie myself however, I'm not sure what they're supposed to be, or what is considered good or 'good enough'.

Ok, does this mean directly that my polar alignment is bad, or lets say if i choose the wrong star in center for example on my 2-star alignment this values are affected?