1392 replies to this topic

[SHFT]

Went out again to practice polar alignment, didn't have my lenses with me so I did use the Z61.

 

Ran in to the same problems again. I don't know why I have that much trouble finding polaris through the polarscope.

I can see some stars but I have no idea if it's Polaris or not. What focal lenght or fov does the polar scope have, maybe that will help, so I can punch the numbers into Stellarium.

 

Another disturbing thing is I noticed a slight wiggle in the RA and I'm not sure this is normal?

 

https://www.youtube....eature=youtu.be

Edited by SHFT, 17 July 2018 - 05:32 PM.

[lucutes]

I sometimes have trouble centering up Polaris with my 9X50 view finder. What I would do is use a diagonal for the Z61 and eyepieces to centre up Polaris. If you have a reticule eyepiece even better. Become familiar with the stars around Polaris. If you set your altitude properly on the mount and the mount is level then it's just a matter of finding true North.  

[Dave24137]

The wiggle could be from the clutch not being tight enough.

However, you don’t want to tighten it so much that it becomes difficult to loosen (which could knock the alignment when forcing it).

While the SGP is actually tracking, does the motor stutter like that, or is the wiggle in the video from you moving it with your hand? Presuming the latter, I don’t think it’s an issue: just tighten the clutch a bit more if necessary. (There’s also additional strain on the clutch, because the Z61 probably isn’t balanced in declination, even if your counterweight in RA is spot on. That’s why it’s good to use a dovetail plate.)

As far as finding Polaris, learn that part of the sky. See Ursa Minor and know where Polaris is. A sky-chart or an app onsite can help. And try having both eyes open. With the left, look at Polaris directly, while looking through the polar-scope with the right. That should get Polaris roughly centered in the polar-scope, and then you can align from there.

Edited by Dave24137, 18 July 2018 - 05:01 AM.

[SHFT]

Clutch should be tightened properly. iOptron has send me some instructions to check the RA play. Going to check it tonight. Really nice of them to provide such manuals.

 

http://www.ioptron.u...SGP_RA_Play.pdf

 

Ever since I mixed up Ursa Major and Minor, I can identify Polaris rather easy but as soon as I look through the scope, I can't see a thing.

I'll try using both eyes and maybe check focus by focussing on the moon, which should be rather easy.

[dciobota]

Thanks for that link SHFT, hopefully this helps others too.  I was going to suggest checking the two grub screws that hold the mounting adapter on, they can get loose.

 

As to finding Polaris, how I do it is align in the late evening, when Polaris just starts to show.  This way the other stars nearby get lost in the skyglow and Polaris is the only one that stands out in that section of the sky.  Makes it easier, since I too get confused at a very dark site if I try to align it at night.

 

Hope this helps, and thanks again for the link.

[andrewweeks]

The support folks at iOptron said the solution would be to widen the hole in the declination adapter by 1mm when using the CEM25 adapter.

"You may use ZEQ25/CEM25 adapter, except you need to enlarge  (~1mm in diameter) the polar scope cover hole on DEC bracket."

 

I just ordered the Polemaster and adapter will let you all know how it goes with widening. Having my son-in-law do the work for me as he has all the good tools. Like Dave, I plan on using the PM on a GEM in the spring so I don't mind spending the money now for the SGP.

 

Andy

 

Hi, Roscoe. Picture included.

 

I used the CEM25 adapter and it almost fit perfectly: almost.

 

I used longer pliers and gently "convinced" the adapter — carefully squeezing two opposing sides, and then the other two (you'll know what I mean when you have it in hand) until it slid most of the way in, then I lightly hammered it (with a block of wood in-between) until flush. Once installed, it will be difficult to remove, so make sure you're committed prior to installation. Also, once set, tighten the internal screw solidly, and the adapter isn't going anywhere. Just be aware of exactly where the (other) securing screw is located for attaching the camera (placed to the side is best).

 

...

[Dave24137]

Good plan, Andy. I will say that it took less than a couple minutes to bend the adapter mostly into place, just with pliers, which then fit flush.

 

Drilling away a mere millimeter runs some risk, and you could chip the finish. Keep us posted.

 

Also, don't forget that the screwhead has to be reduced as well (see photo), otherwise there isn't enough clearance to turn when attaching the camera.

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[andrewweeks]

Good plan, Andy. I will say that it took less than a couple minutes to bend the adapter mostly into place, just with pliers, which then fit flush.

 

Drilling away a mere millimeter runs some risk, and you could chip the finish. Keep us posted.

 

Also, don't forget that the screwhead has to be reduced as well (see photo), otherwise there isn't enough clearance to turn when attaching the camera.

I may end up going to your plan. I'll let folks know either way. 

 

Andy

[SHFT]

I made some progress!

 

I took all your advice and went back to the basics. I mounted my camera with the 18-55mm kit lens and I took some pictures of 1,5 minutes. No startrailing what so ever (except for the one time I forgot to turn on the SGP )

The polar alignment went a lot better after I placed the mount on a little table, so that the polar scope was a little higher. Polaris was very faint but the moon was very bright as well.

 

I framed Casseopeia and it was reasonably sharp, I did notice some weird rings in the picture, could it be due to the massive light polution I have when looking north. (I will upload the picture later.

Edited by SHFT, 24 July 2018 - 03:23 AM.

[andrewweeks]

I may end up going to your plan. I'll let folks know either way. 

 

Andy

 

Good plan, Andy. I will say that it took less than a couple minutes to bend the adapter mostly into place, just with pliers, which then fit flush.

 

Drilling away a mere millimeter runs some risk, and you could chip the finish. Keep us posted.

 

Also, don't forget that the screwhead has to be reduced as well (see photo), otherwise there isn't enough clearance to turn when attaching the camera.

I ended up installing the PoleMaster without boring out the hole. It occurred to me that if I put the adapter in using a vice to compress it the remaining 1/8" it should work... and indeed it did with very little effort. Sitting snug on the adapter face. Can't wait to get out and test the exposure length this week. I may end up replacing the screw instead of grinding it down. I really appreciate you posting what you did @Dave24137! 

 

Andy

[mbphoto]

Anyone ever used an angled camera finder for polar alignment?
I have two here but never got to actually fit the finder onto the polar scope. (I'm at 46° and hate bending down to polar align..)

 

 

Also, since most here seem to use the rather heavy ZS61, did anyone ever use a larger scope (e.g. the Orion ED80 f/7.5 at the SAME weight as the WO 61)?

Since I'm shooting full frame, I'd need that extra focal length, especially since I have a great setup at 420mm and f/5.6 already.

 

 

I'm definitely going to try and use the SGP more this year. Looking into a polemaster as well, because finding polaris really is a PITA with that many stars..

[Dave24137]

You're welcome, Andy. And the vice was certainly the better option.

 

While kind of unnecessary, I still tightened the adapter as normal. That, coupled with the snug fit, ensures that it won't go anywhere. And a replacement-screw is an easier option, too.

 

I've had good results with the Polemaster: I achieved 210-second exposures (unguided) the other night (not yet processed) and I couldn't be happier. With that said, the software can be annoying. Several times I've gone through all the steps, and then in Start Monitor the cross-hairs commence dancing all over the screen, and I have to start over.

 

Moreover, the SGP does not have a Home option (maybe with the controller, but that's a waste in my opinion): so I use a small post-it with a dot on the edge and place it on the screen next to the chosen star, so I know where the Home position is at the end of alignment.

 

mbphoto: I'm at 41-degrees and I've simply raised the height of the tripod: at least on calm nights without much wind. As long as your tripod is sturdy, the additional height doesn't really increase vibration. But the added height does allow for a more-convenient viewing-angle, for alignment.

 

As I've said, long focal-lengths are pushing the SGP past what it's meant for; but if set up well, it can be done. With the FX camera, I think there's an option to enter a DX mode, which will crop the image but zoom you in a bit. I use a D500 and haven't used FX in some time, so I could be wrong there.

 

And finding Polaris, for me, involves keeping both eyes open. You can get Polaris mostly centered by moving the polarscope in relation to your other eye. And then you have a single bright star, which you can align thereon.

 

Also, to ensure that your polarscope is exactly vertical, center Polaris and then move the mount up and down to see if Polaris follows the center line. Tweak, and then when positioning Polaris in the reticle, your alignment will be more accurate.

Edited by Dave24137, 31 July 2018 - 01:30 PM.

[mbphoto]

Thanks Dave

 

Yes, the D810 has crop modes, but I'd prefer cropping in post myself

 

I'll probably get one of these red dot finders for the hotshoe, just to be able to aim the lens somewhere interesting.

 

If my results aren't pleasing enough, I'll definitely give the 420mm (focal length) telescopes some thought.

[dciobota]

Not sure if I'm diverting my own thread, I just thought I'd share an image and a video I took back in June from my dark site.

 

Swan and Eagle, taken at 135mm:

https://photos.app.g...1HbUdcNkAHoF536

 

Video of the Milky Way, taken at 10mm, 1min exposures, iso1600 I believe.  SGP was running at 1/2 speed.  The skip in the video is because I fell asleep not realizing the battery I was using was not fully charged, so I had to switch batteries mid stream.

https://photos.app.g...prFzoktHwqMEPr6

[mbphoto]

That video is amazing!

Didn't know there were soo many meteors to capture during a night

[dciobota]

Thanks!  Next time I'll try to use my astro cam instead and see how that work.  I think some of those streaks at least may be sattelites.

[lucutes]

Hey all. I ran into some issues the other night while imaging the Heart Nebula. Elongated stars were obvious but I thought it was level, "balanced", and decently polar aligned. Compared to my last session with the SGP and the Z61 this session did not go as well. I am wondering if I should start auto guiding to assist the tracking. I did have the OAG and ASi385 mounted but it was not in use. I am thinking the additional weight of the OAG and camera probably went against me this time.  The first image is the bad one and second is the better of the 40 odd subs I took @60sec.  I used the ASi071MC-Pro and Baader 2" UV/IR-cut filter.

 

If you are wondering why I didn't bother auto guiding it is because I am not totally familiar with PHD and it was 5 degrees out, brrr.

 

 

 

 

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[dciobota]

Yeah, I would say at your focal length and that weight you will start getting occasional bad subs without guiding.  I think what is happening is that the momentum is large enough to amplify PE to where you will see those elongations.  I would definitely suggest giving guiding a try.  Barring that, you could also try unbalancing a little bit to put a little tension on the RA belt and motors.  That might smooth out movement due to PE.

[SHFT]

So I bit the bullet guys, I bought the polemaster.

I only did a quick polar alignment as a test due to clouds but it was super easy. Essential astrophotography kit imho!

 

I don't have to work in the next 14 days and the weather seems reasonable so wish me luck!

[alancurry]

I want to thank everyone for the great information in this thread. I also bit the bullet and bought the Polemaster. I was able to press in the CEM25 adapter partly without using pliers. I then finished pressing it in with Quick-Grip clamp. I'm using a 45mm, M4x.70 pan head screw.  

 

 

 

 

 

  

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[ukarmy04]

Hey folks, been following this thread for a couple months now. Managed to get a used SkyGuider Pro from someone on Craigslist and took it out this weekend to Joshua Tree (Bortle 2-3). I used the great tips provided by all of you on how to set up the mount and it worked beautifully.

 

Setup:

SLIK 700DX Pro Tripod

iOptron SkyGuider Pro (with flipped counterweight head)

iOptron Ballhead

Canon T4i (with LPF2 filter removed)

Canon 200mm f2.8 lens (stopped at f2.8)

 

Each of these images were generated from ~60 x 120" exposures at ISO 800. Stacked in DSS and spent only 10 minutes doing some quick stretches, so excuse the poor processing. I also have an AT65EDQ that I want to try, but didn't want to overwhelm myself with the extra weight and longer focal length. Maybe next time I'll give it a shot.

 

[andrewweeks]

Hey folks, been following this thread for a couple months now. Managed to get a used SkyGuider Pro from someone on Craigslist and took it out this weekend to Joshua Tree (Bortle 2-3). I used the great tips provided by all of you on how to set up the mount and it worked beautifully.

 

...

 

 

Well done!!!! Thanks for sharing!

 

Andy

[StarCyclist]

Thanks everyone for your great insights, tips and pictures using this setup. Quick context: I recently got into astrophotography after upgrading my old camera, spending the last three months "playing" with a 600mm lens (equivalent) and a SkyTracker Pro. After several nights taking pictures, rewarding results and encouraged by forums like this one, I decided to get more a little more serious and ordered a Z61 + SkyGuider Pro inspired by Trevor at AstroBackyard (like some of you, I assume). Having said this, I have a couple of newbie questions that hopefully somebody can answer for me:

 

When positioning the telescope for photographing an object with a refractor telescope, I'm under the impression that the only two adjustments are RA (the SGP balanced axis) and the DEC (provided by a head ball or a simple head mount). Remember that I'm coming from a world where the setup didn't need a balance, and positioning for the targeted object was simply achieved by moving the head ball directly connected to the camera.

 

1) Is my assumption correct about how to position the telescope using a balanced setup? (RA and DEC adjustments)

2) Is the DEC adjustment mechanism included in the SkyGuider Pro full package? I'm asking because I'm seeing some setups using a head ball instead... and not sure why.

3) For the #2 scenario, wouldn't it be better to use a head mount such as the Manfrotto 410 for small adjustments? This actually will provide more flexibility to position the telescope and find the target (but this probably would throw off the balance, not sure...)

 

Thanks so much in advance!

[dciobota]

Welcome to the forum and congrats on the new kit!

 

Here's my setup:

https://www.cloudyni...e-it/?p=8528056

 

The skyguider pro photo package comes wit what you see in the pic: the dec adapter with counterweight and shaft plus the dec head that has a vixen style saddle to mount the scope dovetail on.  So if you ordered the correct kit you should hav3 everything you need.  If not, you can still buy those pieces separately.

 

Once you mount everything that way, you can balance the ra by loosening the main clutch.  Then, you can balance dec by rotating the ra until the telescope is on one side of the mount.  Then tighten ra and loosen the two dec saddle knobs until the scope rotates freely in dec.  Then balansce scope and camera by sliding the dovetail until youre well balanced.  Btw, you don't really need to be well balanced in dec, since only the ra tracks and guides.

 

Hope this helps.

[ukarmy04]

Just thought I'd share some photos of a modification I'm playing around with that might help with declination adjustment on this mount.

 

I added a retaining bolt that passes through the circular declination plate and into the counterweight bracket so that it sandwiches everything together, even when the two thumbscrews of the plate are loose.

 

I put a 3/8" to 1/4" reducer into the counterweight bracket and passed a countersunk 1/4" bolt through the assembly. On the inside of the counterweight bracket, I added a 1/4" nut to hold it all together.

 

I think the whole thing could benefit from some Teflon washers placed on either side, but I didn't have any with me when I made this.

 

From testing briefly indoors, this modification seems to help a little bit. There is still a little bit of movement when I tighten down the two thumbscrews of the declination plate, but at least it's only movement about the declination axis. There is no longer vertical play between the declination plate and the counterweight bracket.

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Edited by ukarmy04, 22 September 2018 - 11:41 PM.