Hole design observatory build

[wimvb]

The first imaging night from the obsy has come to its end. Just before midnight clouds rolled in again. I started imaging ngc 925, a small but very nice galaxy in Triangulum. Focusing the guide camera wasn't any trouble. I focused the imaging camera with a Bahtinov mask on Capella, then moved the scope until I could see that star in the guide scope fov. Moved the guide head until the Bahtinov pattern indicated focus. Easy.

I had some problems with devices not connecting, and I had to add a usb hub to get stable connections. I lost connection between the obsy network and my computer indoors a few times. Solved that by moving downstairs and connecting with an ethernet cable. Finally I found out that the mount had been in summer storage too long. Guiding showed severe backlash/stiction in DEC, which I will deal with tomorrow. Guiding RMS was 0.55" in RA, and a whopping 1.5" in DEC with a devastating saw tooth pattern. I will also need to check if the scope is balanced properly.

I turned off guiding and went for bright targets with short exposures instead: Taygeta in the Pleiades and M43. This worked good enough untill the clouds put a stop to the fun.

Tomorrow I'll take calibration frames (saw some dust bunnies on the light frames), and start tinkering with DEC.

All in all I'm pleased to be back in business again. Next session I will test guiding and automated flips.

[Firas]

Here is Wim happy and proud with an almost finished observatory and a healing knee. 

 

The 8 ONTC f5 was finally erected on the pier tonight. 

Soon OAG to be attached, then collimation with Paracorr, polar alignment, some software work and off begins the galaxy hunt.

If all goes as planned and weather permits, that is. 

Looking forward for first light.  

  

[wimvb]

As I reported yesterday, first light of the obsy was a mixed success. DEC guiding was all over the place, but RA was pretty good. Rather than spending the entire cloud free spell trouble shooting, I decided to go for short exposure AP. So, here's my first ever Orion nebula/Trapezium. (I haven't imaged this nebula before, because it was always obscured by trees or to low over a neighbour's house.)

Ok, not my usual standard. But this is only a very Quick & Dirty processing of 4 minutes (!) worth of data before clouds spoiled the fun.

R: 25 x 3 seconds (75 s)

G: 25 x 3 seconds (75 s)

B: 30 x 3 seconds (90 s)

I haven't taken any calibration files yet, so this is just stacked, and stretched of the raw image files.

Edited January 20, 2020 by wimvb
gradient removal

[gorann]

Not bad at all for 5 minutes. And you can use it to save the Trapezium if you also take some longer exposures.

[gorann]

13 hours ago, Firas said:

Here is Wim happy and proud with an almost finished observatory and a healing knee. 

 

The 8 ONTC f5 was finally erected on the pier tonight. 

Soon OAG to be attached, then collimation with Paracorr, polar alignment, some software work and off begins the galaxy hunt.

If all goes as planned and weather permits, that is. 

Looking forward for first light.  

  

Fantastic bino-imager you have there!

Edited January 21, 2020 by gorann

[Firas]

6 hours ago, gorann said:

Fantastic bino-imager you have there!

Thanks Göran. 

We were actually planning a dual take on a very interesting galaxy. W'll see how that goes, when all is fully operational. 

[wimvb]

Until then, it's a cyclops. 

[wimvb]

Proper first light, 2 nights spent with ngc 2683.

Using the obsy, some things become apparent. Guiding has to be improved. The guide graph shows what is either backlash (DEC) or stiction. I tried to wiggle the saddle, but it seems stable enough, so I will poke around with allen keys to see if the DEC axis is actually a bit too tight.

The roofs are not sliding smoothly enough. Especially the roof half over my scope is difficult to open and close. It will have to do this season, but during summer recess I will install a proper V-rail with metal wheels.

I have ordered an anemometer to complement my weather station (which is not installed yet). I will probably redo the housing for the weather station also. After that, integration with Ekos, so that at least I will get warnings when clouds roll in or the wind gets too strong.

The East pier has to be made higher. I will adjust the adapter height about 2 - 4 inches. Apparently the EQ6 is a bit smaller than the AZ-EQ6.

The hole that I made in the pier adapter for the central bolt underneath the mount, is slightly too large. This makes it more difficult to do AZ adjustments during polar alignment. I'll fix that by inserting a piece of metal or plastic around the central bolt. As it is, the bolt & mount can move sideways when you tighten it after polar alignment. I hadn't really thought of this when I designed the pier adapter.

[TerryMcK]

A very good write up Wim. I look forward to seeing more posts on this really interesting thread.

[Laurin Dave]

7 hours ago, wimvb said:

Proper first light, 2 nights spent with ngc 2683.

Using the obsy, some things become apparent. Guiding has to be improved. The guide graph shows what is either backlash (DEC) or stiction. I tried to wiggle the saddle, but it seems stable enough, so I will poke around with allen keys to see if the DEC axis is actually a bit too tight.

The roofs are not sliding smoothly enough. Especially the roof half over my scope is difficult to open and close. It will have to do this season, but during summer recess I will install a proper V-rail with metal wheels.

I have ordered an anemometer to complement my weather station (which is not installed yet). I will probably redo the housing for the weather station also. After that, integration with Ekos, so that at least I will get warnings when clouds roll in or the wind gets too strong.

The East pier has to be made higher. I will adjust the adapter height about 2 - 4 inches. Apparently the EQ6 is a bit smaller than the AZ-EQ6.

The hole that I made in the pier adapter for the central bolt underneath the mount, is slightly too large. This makes it more difficult to do AZ adjustments during polar alignment. I'll fix that by inserting a piece of metal or plastic around the central bolt. As it is, the bolt & mount can move sideways when you tighten it after polar alignment. I hadn't really thought of this when I designed the pier adapter.

Nice write up and great image Wim..  I had that issue with my AZEQ6, fixed it by cutting up a plastic bottle into a thin strip and wrapped it around the bolt to take up the slack

Dave

[wimvb]

3 minutes ago, Laurin Dave said:

Nice write up and great image Wim..  I had that issue with my AZEQ6, fixed it by cutting up a plastic bottle into a thin strip and wrapped it around the bolt to take up the slack

Dave

I had something similar in mind. Or a bit of aluminium tape around the bolt near the head. I probably drilled a 13 mm hole to accept a 12 mm bolt for easy assembly. But at the time I didn't consider that this would affect polar alignment. Ah well, I'm an electrical egineer not a mechanical, by trade. There's always the possibility of a V 1.2.

[Alan White]

I have just this thread all the way through, what a great build.

The knee injury had me curling my toes in sympathy, I have kneecap issues in
both of my knees, so literally feel your pain, hope the recovery continues.

That observatory design as used by Gorran and now you, is that a more usual design in your area?

 

Edited January 26, 2020 by Alan White

[wimvb]

25 minutes ago, Alan White said:

hope the recovery continues

The recovery goes well, thank you.

26 minutes ago, Alan White said:

That observatory design as used by Gorran and now you, is that a more usual design in your area?

There are now at least three of these that I know of 😁; two single pier observatories by Göran, and a dual pier version by me. I think that Göran could have made a traditional ror if he'd wanted. In his original design, he let the roof slide down to the ground on two removable beams. He later added the raised supports. The sloping roof design has several advantages, one of which is that it's simple while easy to clear from snow. Another is that it allows for a lower south facing wall. The disadvantage is that if it runs as smooth as it should, the roof will open by itself, and you have to lift it to close. So you do need a winch. Since I'm on a south slope, a traditional horizontal running roof to the north would be very impractical unless I'd raise the whole obsy. There's simply not enough clearance to the north. East/West sliding roofs would result in a very long and heavy construction, at least 8 m overall. Plus obstructions to both East and West. As it is, the observatory fits very nicely with the surrounding landscape.

[Alan White]

Thanks Wim, that makes a great deal of sense.
I had not thought about the sliding the roof back issues and needing a winch.
 

[RAR_MI_USA]

Very nice observatory and great work and visuals throughout the process. May I ask about the steep roof incline downhill? Do you have it motorized or somehow assisted in it's return route? The roof's grade downward looks awfully steep and I could imagine a struggle bringing it back if done simply by human power, depending of course, on the weight of the roof, and with snow and ice buildup possibly being a factor in added weight. Opening it up would pose another problem with the weight working to pull away down the incline.

Edited March 4, 2020 by RAR_MI_USA

[wimvb]

Thanks, @RAR_MI_USA.

The roofs are operated by one winch each, 12 V, 2000 lbs. The East roof will slide down on its own accord, but the West roof doesn't run as smooth, and needs help opening. During summer recess, I'll need to check that. I'll probably install rails and V groove wheels to make it smoother. In the future I may install an electric fence system to automate the roofs. 

[gorann]

7 hours ago, RAR_MI_USA said:

Very nice observatory and great work and visuals throughout the process. May I ask about the steep roof incline downhill? Do you have it motorized or somehow assisted in it's return route? The roof's grade downward looks awfully steep and I could imagine a struggle bringing it back if done simply by human power, depending of course, on the weight of the roof, and with snow and ice buildup possibly being a factor in added weight. Opening it up would pose another problem with the weight working to pull away down the incline.

The winch is no problem and a cheap addition compared to building a v-shaped roof that is also obstructing much more of the sky, as Wim pointed out.

[RAR_MI_USA]

Great. The winches should work perfectly for you needs. Again, very nice Obs and visual timeline. I wish you many clear skies!

[BigMisterP]

On 04/03/2020 at 14:52, wimvb said:

Thanks, @RAR_MI_USA.

The roofs are operated by one winch each, 12 V, 2000 lbs. The East roof will slide down on its own accord, but the West roof doesn't run as smooth, and needs help opening. During summer recess, I'll need to check that. I'll probably install rails and V groove wheels to make it smoother. In the future I may install an electric fence system to automate the roofs. 

Just to confirm,

The winch will let the cable down, but, the roof may need manual "assistance"to open?

But, closing is fine as the winch deals with it.

Do you have sensors to stop to winch pulling too far, or did you just measure what you needed.

[wimvb]

42 minutes ago, BigMisterP said:

Just to confirm,

The winch will let the cable down, but, the roof may need manual "assistance"to open?

But, closing is fine as the winch deals with it.

Do you have sensors to stop to winch pulling too far, or did you just measure what you needed.

Correct. There seems to be just a bit too much friction somewhere.

There are no sensors, as I operate the winch by hand control (the yellow box in Göran's image). No automation yet.

[wimvb]

A short update with images.

During summer recess (May - August) I did some more work on the obsy. The biggest task was to replace the rubber wheels under the roof beams by proper v-rail and wheels. This lifted the roof by about 5 cm. As a result there is now a gap between the roof and the south wall. I need to close this with a board or I'll have the largest pigeon coop in the neighbourhood. Compare the last image here with Firas' image from earlier this year. 

I did some work on the outside, including painting. Inside I sanded the floor boards and treated them with wood oil. The boards are a bit warped and have a very rustic look after sanding. And finally I installed a box (60 x 40 x 40 cm) around each pier, where I can have power and network outlets. I also have a permanent power and ethernet cable from the house to the obsy.)

Late this afternoon I put the mount back in its place and got the 190MN in. Next will be to attach the camera and wire everything. Next weekend I expect to be up and running.

Btw, up and running: my knee is doing well now. I can bend it almost as much as before my accident, and have nearly full strength again.

Edited September 6, 2020 by wimvb

[wimvb]

On 03/01/2020 at 16:28, sloz1664 said:

Your next design is a "safe" path from your house to the Observatory.

It took a while, but here it is

Some time ago we hired someone to do help with rough landscaping in our garden to be. The boulders that were blocking the path to my obsy were removed and I put some granite slabs in place. Then filled up with gravel. So now I have a safe path to the observatory. No more broken knee caps hopefully.

Edited July 9, 2021 by wimvb

[sloz1664]

Hi Wim,

Glad to see the "Safe Path"  has been installed. Hopefully Trouble Free imaging from now on 👍

Steve