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GuySt

No stars in HEQ5 Polar Scope ??

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Hello everyone - my first post. I'm 62 and newly retired. Taking up astrophotography, a long desired hobby, now I've the time to devote to it (I'm a long-time photographer so the camera/imaging end of things I know well).

Gear (all brand new except the Nikon and Surface laptop): Sky-Watcher HEQ5, Williams Optics RedCat 51, ZSO 120mm mini camera and scope for guiding, Nikon D7500 camera, MS Surface Laptop with all the software to use APT/Stellarium/ASCOM (tested and all the things connect !! and I can take images with the Nikon and slew the mount).

Tonight was my first time outdoors as I finally got the Battery Pack to power everything. I live in a condo in Madison WI, Bortle class 6, so I must go elsewhere to use this gear. I've done the homework while waiting for the battery and thought (?) I knew what to do to polar align the mount.

But nothing doing, sad to say. Set up the tripod , N leg towards NCP and levelled it. Put mount on tripod. Latitude already set to 41-degrees at home. Plugged it into the battery and powered it up. Took off the caps for the Polar Scope, rotated DEC axis to make sure view through Polar Scope is good.

Looked through the Polar Scope and saw no stars. Nada. I did see some specks, but they must be on the eyepiece/focuser as the specks rotate if I rotate the Polar Scope focuser. I turned off the mount and looked through the Polar Scope. No stars; completely black. I confirmed that there is a light path through the Polar Scope by using my cell phone flashlight to shine a light through it from the top end which I could see on my hand held near the eyepiece.

Now ... I have poor eyesight. So, the issue may be the Polar Scope, or my eyes. And after all that, the reason for my post ...

I want to know if it's necessary to do Polar Alignment using the built-in Polar Scope? I have read about Drift Alignment. And software using a guide scope (PHD2, etc.). If I get the HEQ5 setup with the RA axis pointing towards the NCP can these software-based tools get the HEQ5 aligned sufficient for good astrophotography? I'm thinking it may be better with my bad eyes to use a tool that uses images for alignment that I can better see than what I can see through that Polar Scope.

Thoughts?

Best regards - Guy S.

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Well you are saying you are 2 degrees off, you are at 43 and the Latitude is set to 41. Also Polaris is fairly bright and the other advantagous to us is that there is not a lot else around it. It is one of the few constellations easily found if you are at a dark site as it in effect sits out of the milky way line of sight.

How well focused was the polar scope? If incorrect then you would see the reticule as that is fixed in position but the stars would be out of focus and being stars they tend to be dim and you see nothing.

I would sort out the latitude setting, presently just reads wrong. Take maybe more time with the N leg being well directed at Polaris. Unsure how to easily accomplish this - almost think a piece of wood with a heavy line drawn on it would be useful and sight along it.

Rather unfortunately in astronomy things do not wander into view, they do wander out, rarely wander in. And we think that we are within 2 degrees and more likely we are within 5 or 10 degrees and nothing is in view if that is our accuracy.

I would say spend 10 minutes extra getting everything set up just that little better. But do check the polar scope focus.

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You ask if there is another way of doing polar alignment without using the polarscope.  Drift alignment is somewhat tedious and time consuming.  But there are two bits of software (needing cameras) that you can use.  

Polemaster (not cheap but makes PA a doddle). 

Sharpcap does a routine if you are techie enough, never used it but I believe it uses a guidescope camera.

Going back to manual polar aligning, first of all have you checked the polarscope is orthogonal (tilt the mount during the daytime and look at something like the top of a telegraph pole through the polarscope, and turn the RA.  If the top of the telegraph pole wobbles around, you need to tweak the little grub screws in the polar scope until it stay in the same place.  Bit fiddly but one time only job.

Actual PA Make sure, you are pointing North and your latitude is correct on the dial, make sure the Alt/Az bolts are roughly sticking out the same length each side, this will give you some room for movement and as you say rotate the Dec so there is no visual obstruction.

Personally I have been using Polemaster for about 3 1/2 years now, and would not want to go back to the old back and neck aching and kneeling manual method any more. 

Carole   

 

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They are NOT the easiest thing to use! 🙄 A couple of random thoughts.
(Before you give up and look for better ways? See Carole above etc!)

I echo ABOVE re. focussing. The multi-turn focus may be a long way out.
I suggest you might "hang on(!!!)" to the setup -- try to (carefully!) "tilt"
it to a bright object - During *DAYLIGHT*: TV aerials... Church Spires(?)...
You can then be sure you have things at "infinity" in focus...

For an initial (quite good) "latitude" mount setting, I use a Digital Level:
(Available from "good stores"... Ebay -- "Hundreds of other uses" etc. 😎I

27-10584-0_xl.jpg.9ab38ecd3deee5191137775279a0e43b.jpg

Just lay inside the Saddle - adjust the inclination to 5n.m whatever deg! 😉

I also draw a chalk (whatever) a "North-South" on the "patio" (whatever)
using the Sun's Shadow at local solar noon! Rotate the setup to match.

I can now be sure I have the mount "pretty well" aligned, before I try to
look throught the polar scope! I THEN found I could see stars through
the polar scope, but I couldn't see the graticule easily! I made a DIY LED
illuminator... It worked! I could align the mount. But I still "gave up". lol! 🤣

But I would STILL commend the above way to set the scope up (nearly)!
(It might be all you need, until you can/do explore the better methods...) 🙂

Edited by Macavity
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Did you rotate the DEC axis by 90 degrees to line the hole up in the DEC axis?

The polarscope is unlikely to be in focus when the mount arrived, on my mounts the eyepieces have all needed unscrewing a few turns to get them focussed.  You can do this in the day by tilting your mount so it points at a distant object, but take care it doesn't tip over.

Polar alignment can be done electronically, often faster and much more accurately, but not for free.  If you're going to guide then PA can be done with a finder guider and SharpCap Pro, which is a cheap option.

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All the advice above is good regarding alternative methods of PA. A couple of points from me regarding the traditional use of the polar scope. First, the altitude scale on the mount is not accurate, I haven’t took much notice of mine for a while. I think I live at 52’ (that’s how often I take notice of it) but when accurately polar aligned my altitude scale is nearer 60’ that’s where it is sitting as I type and I have extremely accurate pa using the traditional method.

 

If you continue with manual PA an app like Polar Align Pro can assist as it has a daytime polar align routine which is not accurate enough for AP but will at least get Polaris in the fov of the polar scope for later fine adjustment.

 

Edited by Jiggy 67
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Hi GuySt,  thanks for posting. As others have replied take things a step at a time. Carole's advice concerning the polar scope being orthogonal is a job you can do in daytime but if your HEQ5 is like my old CG5 you may have to temporarily take out one of the dec knobs to lower the altitude of the view through the polar scope.  A job best done in daytime in case one of the tiny grub screws in the polar scope drops off! Slight turn on one screw-check and repeat carefully. The three screws work against each other.. I would hope your manual describes the process better than Celestron do.

Your problem is made worse having no garden to set up permanent markers to help align the tripod each night. If you try to set up as it is getting dark Polaris will stand out amongst the sky being the brightest star. 

Once you have adjusted the focus of your polar scope you will find subsequent attempts on other nights easier. You might then want to use the Skywatcher  Star Adventurer Mini App (free) on a mobile or tablet to help get a more precise polar alignment. While the App is meant for the Star Adventurer Mini you can use the polar alignment utility to manually set polar alignment. It is quite easy to do. This is not as precise as a Pole Master or iPolar device but depending on tbe focal length of your imaging gear can be fine. It is however much more precise than just lining up Polaris through the polar scope.

Good luck with your efforts. Everything worthwhile takes time and patience.

Cheers,

Steve

Edited by SteveNickolls
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Sounds like your polarscope needs focusing to me. Firstly, take out the polarscope and in the day point at the sky and rotate eyepiece till reticule is in sharp focus. Then at the objective lens end, there is a locking ring, loosen the ring and then turn the whole tube whilst looking at a distant object till in focus. You should now see through the polarscope an in focus reticule and an in focus view of a distant object. Tighten up the locking ring. Next you need to calibrate the polar scope with the ra axis. To do this you must lower the altitude scale to around zero so you can view a distant object through the polarscope. Using altitude and azimuth centre the crosshair on some distant object then rotate the ra axis through 180 degrees. If the crosshair stays on target you are calibrated. If not you need to adjust the reticule. This is done by adjusting the three grubscrews that hold the reticule. To calibrate you need to put the crosshair halfway between the original position and the displacement. Move ra axis back through 180 degrees and check again. Repeat this process till the polarscope crosshair remains on target as ra axis is turned through 360 degrees. This may all sound confusing but once done it is quite a simple procedure. There are videos on u tube explaining this. Once the polarscope is properly focused and calibrated set the altitude scale to your latitude and point the mount North. Looking through the polarscope rotate ra axis till reticule corresponds to position of polaris and then fine adjust altitude and azimuth till polaris is in the little circle. If you do all that you will be polar aligned. For visual astronomy none of the above is needed, just set your latitude and point North. As I do not do imaging I can't comment on the desired accuracy needed. Hope this helps. 

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Hi Guy,

I'm still a relative beginner to this game too, and I also use a HEQ5. I was very confused at the start with all of the various procedures to get set up properly but I'm getting the hang of them well over time with practice. I would recommend getting the hang of PA with the HEQ5 polar scope before you look for other methods. 

It sounds like you have your Dec axis rotated through 90 degrees and you have a clear light path. I second the advice above about trying this out during the day so that  you have focus at 'very far' if not infinity. Anything that is more than a little out of focus whether it's through the polar scope, guide scope or main scope can mean that you see nothing..... coming closer to focus will give you the famous donut and from there on it's easy.

Then on the next clear night, twist your neck so that you're looking through the polar scope with one eye, and keep the other eye open, looking at Polaris. You'll have a good gut feel about how to bring Polaris into view in the polar scope, and once you see it in the scope, you can align it to the 'Polaris position in polar scope' time value.

One last suggestion - adjust the polar scope LED brightness using the handset so that you can just see it clearly but it's not outshining any stars in the field of view.

I now use SharpCap and a guide camera to do PA, and it works very well, but it's not necessarily any easier than using the polar scope. I'm happy that I know how to use the polar scope as a fall-back position if needed.

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I am ... embarrassed. I think I know what I did; I may have left the counter-weight shaft INSIDE the RA housing. Which would certainly have obscured the view through the Polar Scope. Perhaps the light I saw when I put my cell phone flashlight was light reflected by the chrome shaft? As one of you suggested I did a YouTube search for Polar Scope alignment and was going to follow the steps one of them suggested. As I was holding the mount in my lap I took off the Polar Scope caps, rotated mount so that the hole through the RA axis shaft was in place then had a look through: silver! And then the DOH! moment: the oounter-weight shaft. Pulled in out and ... oh, look, I can see things!

But all is not lost. Confess that the Sky-Watcher manual about aligning things is less than clear. The YT vids are terrific (especially Martin's video) and my goal today is to get the Polar Scope aligned. Then I'll get it back outside. I think perhaps I may just take it down the street and get comfortable with setup, alignment, take-down before driving a half hour to dark skies.

I thank all of you who replied. Truly. So very good advice I intend to follow.

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We’ve all done it or similar, try scratching your head for 15 minutes trying to work out why all is black through the ep and then realizing the scope front cap was still on!!. 
I wouldn’t polar align without the weights on though, you might get perfect pa and then add the weights which will shift the mount 

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Hi GuySt

I'm 69 and I do this stupid stuff all the time. I am, however, making a laminated check list to reduce the rate of idiot failures.

If like me you find it difficult to get back up having bent down to look through the polar scope , you may benefit from using a webcam on the polar scope. I just bought a cheep webcam and made a little adapter to connect it to the eyepiece.

I use Sharpcap to look at the image. Works a treat and no more groaning trying to get back up!

Just a suggestion. I have only just started using it and I'm chuffed as punch.

cheers

Gaj

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Would have suggested the counter weight bar not extended, if no one else did, but see you realised it yourself :)

Like Padraic I would also recommend dimming the red lighting in the polar scope (via the utilities menu) - otherwise it will drown out Polaris.

If using a smart phone, the Synscaninit2 app is great - it can show you a graphical view of what you should see in the polar scope, with the position of Polaris.  It has both the 'old' and 'new' style of polar scope, so you must pick the one corresponding to your scope.

For comfort and more precise adjustment, I use an angle finder for the polar scope. Comes with 2.5x magnification, which makes it much easier to place Polaris precisely.

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A shout-out and Thanks to Carole (carastro) who's mention of PoleMaster led me to research it. And buy it. And use it. Last night!! Could hardly have chosen a worse night, TBH. Very bright moon (97% full), a bit overcast, and in the midst of my city (Madison, Wisconsin) which is, according to the ClearOutside app Class 8 Bortle. But, the PolarScope could "see" more than I could see with binocs!!

I ran the app and though it is different than the online video I'd reviewed I think I actually got the mount correctly polar aligned with it!! On the first go.

Though I'd not intended to take any images, just work on setup, polar aligning, etc., I could not resist. Here is the result (using only lights and darks, no flats or biases used in Sequator). It's been post-processed to reduce the noise (without use of those missing flats and biases), scaled 50%, DPI reduced to 120dpi, and saved at 90% JPG in Gimp 2.10.20

I'm excited. Only one odd thing (besides the PoleMaster app being completely different from what I expected) -- it's clear when scrolling the light frames that the star field is moving. The stars stay sharp and do not trail (30s exposures at 800 ISO with my Nikon D7500) but the star field is shifting, left to right.

Q1: Is that supposed to happen?

I thought the point of an EQ mount is that it moves with the earth's rotation so, well, things don't move in the scope's FOV.

M31_20200928_output_Sequator_01.jpg

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