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Magnus_e

Starting summers observatory project

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1 minute ago, Gonzo said:

man, don't we over engineer our observatories sometimes... lol

That's true. If you look at garden sheds turned into hobby workshops connected to the mains, i'll bet you will find a lot of dodgy viring :)

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Yay! Almost seven months after starting the build, I have started the install :)

I managed to finish the south an west wall, mount the north wall and wheel in the pier. Then it started snowing....

Hopefully I will complete the obsy install tomorrow. I'll add all the servers and gizmos and the awx, but I will hold off installing scopes and cameras untill the weather clears.

I'm not going to be able to test the wather resistanse in a while, as all wather is frozen here now. I am hoping for no kondensation thoug..

DSC_0483.JPGDSC_0486.JPGDSC_0488.JPGDSC_0490.JPGDSC_0491.JPG

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I cannot believe it, it's done <(''<) <( '' )> (>'')>

I really feel I have to add a huge 'Thank You' to my parents for helping me in this build. It ended up being my mom and I that finally got the roof up the stairs. For the 'portable...' pier even my parents neighbor helped to get it up the stairs.

There are some things left, like installing the scope, polar aligning and such, but all servers etc is installed. Will have to tidy up the plastic sheeting around the edges, but rain finding it's way between the roof and building will not be an issue.

Got to test parking and unparking the roof a couple times. To my surprise the full travel of the linear actuators was the limiting factor on how far the roof opened. The roof did however not hit the awning of the house, so I'm happy with how it turned out. Should be able to image from the East trough the zenith and to the west horizon.

Just have to wait for some clear skies to test everything. Can hardly wait :)

DSC_0494.JPGDSC_0496.JPGDSC_0499.JPGDSC_0498.JPG

 

Edited by Magnus_e
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Looks really nice, well done! 

Must feel good that it's finally ready for your scope. Looks like we have used the same kind of wall planks, I'm a couple of weeks away from being done though :)

 

IMG_20161111_123605.jpg

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Thanks for the comment poogle, looks like you are making progress fast. You should be happy that you are building it on the balcony. Getting mine up from the basement was a two month incremental task. With everyone busy with work and such, this time of the year.

The 'everything here is frozen now' comment has changed to it's poring down with rain. Super happy that the install was completed in two days, and the obsy did not have to sit outside under a tarp, with servers and all in the rain. Next time I visit the remote location I will truly see if there are any leeks.

I have logged on a couple times and everything works, except a networking issue. When i try to run a speedtest.sh script (that downloads a 500MB file) I have, the download speed starts low then goes up to 1MB/s, then it starts dropping. When it drops down to ~0KB/s I loose connection, and cannot reconnect for a while. I hope it's a easy fix, but don't know... I did not experience that at any point when testing in the garage.

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A quick visit to the remote location, and I'm happy with the two day trial.

There is 5 drops of water inside, and its a easy fix. I could feel that the inside of the inlet vent was moist, so I think angling it upwards will let it drain outside rather than inside. Other than that everything was dry to the touch. Even my wet snowy footsteps that I left behind when building had completely dried up when it was poring down outside.

The networking issue was a easy fix. I moved the zyxel (powerline adapter) from a 1 -> 4 socket adapter to a short extention cord with no power switch, and it helped a lot. From hovering around 300Kb/s and dropping out from time to time, its now hovering around 5Mb/s. Not extremely fast, but a lot faster then wen I was testing in the garage, and that worked.

For anyone not aware on how to speedtest over ssh, then the command is:

wget --report-speed=bits --output-document=/dev/null http://speedlayer.com/downloads/test500.zip

The link can be the testfile of any speedtest.

Ill mount the dlink ip camera and the hardwired safety button to close lid in case of network loss, and do some remote tests.Speedtest.png

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powerline adapter should not really be connected to an extension, but straight to the wall socket to get maximum output.

Glad to see you're almost 100% up and running, almost there.

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43 minutes ago, Gonzo said:

powerline adapter should not really be connected to an extension, but straight to the wall socket to get maximum output.

Glad to see you're almost 100% up and running, almost there.

I know, it's one of those compremizes... Where the router is located theres only a 2x wall socket. The Zyxel is so big that it would cover both. In that case a pc, monitor, printer, scanner, etc would have to be powered by the Zyxel pass trough. a 1.5 meter extention cord is the best option for now. Shall see how it works out, or if I have to think up an option.

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Doesn't seem like I can catch a break on this winter ting.. It has been raining almost every day over the last ten days or so, since the obsy was completed.
It is atleast getting a good weather test :clouds2:

The network has settled on a very stable 10Mb/s, so that should hopefully work. I also found that the dlink camera can give me a clue if it's clouded or not. Even in complete nighttime I can see the clouds to the west illuminated by a little village. In twilight I can see everything thats going on, and rain is obvious.

Day

dlink-daytime.png

Sivil dusk

dlink-sivil-dark.png

Clouded night

dlink-night.png

Night time IR and rain.

dlink-rain-now.png

Hopefully the rain will clear some time, so I can install the mount and get on with imaging :bino2:

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Hi, again :)

The obsy has gotten a real weathertest with a lot of rain, and it's 100% dry to the touch inside :)

Last night I installed all the gear (- flatfield lightsource, and electronic dustcap), and I managed to do a two star align on the avx.

I did encounter a issue, that stole many hours. I made a tread for it here Dew heaters destroys powerline network signal

Atlest I managed to do an initial focus of the scope and guider, align the scope, guidescope and red-dot to the same point and two star align the avx.

Hopefully I will have time today to start polaraligning the mount.

First ever image from the obsy. Not stars, but getting closer :)

light_RGB_streach.png

 

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Consept proved!

Just finished first 10 min sub of andromeda :)

I can happily say tath the Orion ssag (qhy5) is working with INDILib 1.3.1. I have not got it to work in erly testing, but now it calibrates and guides with minor changes to default settings :)

The new EKOS interface also lloks great. The image could have rounder stars, but I have not finished polaraligning yet, so room for improvement.

ekos.png

first.png

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It's been a while since I processed a image with only an hour of subs, but heres first light of Andromeda.

6x 600 sec lights at iso 800.

No calibration subs.

Stacked and processed in PI.

Will have to nail focusing and do a proper polaralignment, but I'm happy most of the obsy is working.

one-hour-andromeda.png

I had to leave for home to get ready for work tomorrow, and I'm not comfortable leaving it imaging alone yet. Will have to 'get to know it' first.

Some pics of the install :)

DSC_0519.JPGDSC_0527.JPGDSC_0522.JPGDSC_0525.JPG

DSC_0526.JPG

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Network issues fixed!

Added a cat6 network cable to the build, and now have stable 300Mb/s in the observatory.

 

Have done some more testing the last week... I have been imaging remotely from my home, and things just work (except for network speed).

I have been having issues with the powerline adapter. Dew heaters killing network, guiding aborting when a image is downloading (due to low bandwith), aso. However! All drivers is working, EKOS is a joy to use and the only thing left to do is polaraligning.

It's clouded today, but sooon I will have a calibrated observatory :)

 

--2016-12-03 16:33:31--  http://speedtest.tele2.net/500MB.zip
Resolving speedtest.tele2.net (speedtest.tele2.net)... 90.130.70.73, 2a00:800:1010::1
Connecting to speedtest.tele2.net (speedtest.tele2.net)|90.130.70.73|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 524288000 (500M) [application/zip]
Saving to: '/dev/null'

     0K .......... .......... .......... .......... ..........  0% 18.9M 3m42s
    50K .......... .......... .......... .......... ..........  0% 18.4M 3m45s
   100K .......... .......... .......... .......... ..........  0% 34.3M 3m11s
   150K .......... .......... .......... .......... ..........  0% 43.5M 2m47s

511800K .......... .......... .......... .......... .......... 99%  333M 0s
511850K .......... .......... .......... .......... .......... 99%  319M 0s
511900K .......... .......... .......... .......... .......... 99%  261M 0s
511950K .......... .......... .......... .......... ..........100%  306M 0s
512000K                                                       100% 0.00 =14s

2016-12-03 16:33:45 (301 Mb/s) - '/dev/null' saved [524288000/524288000]

DSC_0530.JPG

 

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A little update on Observatory 17b :)

From the time of the install there have been some changes. The biggest one is moving to a mono CMOS camera (asi1600mm-c) with filter wheel and ZWO LRGB + Baader HaS2O3 filters.

I have also installed the remote controllable dust cap, and fixed down the styrofoam plates. (One night of imaging a styrofoam plate came loose and almost ended at the neighbours).

Weather has not been kind, but I did get a weekend of imaging after I installed the new camera, and did manage to remotely set up and get a image I'm happy with.

And just to add, the water proofing of the obsy is spot on. I run the fan always when I'm not imaging and there are no moisture, even with all the rain there has been.

 

So some pictures of the changes, and my first good remotely collected image :)

 

filters-lrgb-HaS2O3.jpg

 

asi1600-efw.jpg

 

dustcap.jpg

 

scope.jpg

 

vapourbarrier.jpg

 

insulation.jpg

 

 

NGC 1499, California nebula.

California-NGC1499_DCrop_DBE_MMT_HT_HDRMST_LHE-UMDSO-MTS-2-edge.png

 

Also, feel free to visit the observatory's website. :) (in my signature)

Edited by Magnus_e
images, reordered
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If you are still having issues with the powerline adapter why not invest in one that has a socket built in? 

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5 hours ago, rodrigol said:

If you are still having issues with the powerline adapter why not invest in one that has a socket built in? 

 

On 12/3/2016 at 17:03, Magnus_e said:

Network issues fixed!

Added a cat6 network cable to the build, and now have stable 300Mb/s in the observatory.

 

Have done some more testing the last week... I have been imaging remotely from my home, and things just work (except for network speed).

I have been having issues with the powerline adapter. Dew heaters killing network, guiding aborting when a image is downloading (due to low bandwith), aso. However! All drivers is working, EKOS is a joy to use and the only thing left to do is polaraligning.

It's clouded today, but sooon I will have a calibrated observatory :)

 


--2016-12-03 16:33:31--  http://speedtest.tele2.net/500MB.zip
Resolving speedtest.tele2.net (speedtest.tele2.net)... 90.130.70.73, 2a00:800:1010::1
Connecting to speedtest.tele2.net (speedtest.tele2.net)|90.130.70.73|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 524288000 (500M) [application/zip]
Saving to: '/dev/null'

     0K .......... .......... .......... .......... ..........  0% 18.9M 3m42s
    50K .......... .......... .......... .......... ..........  0% 18.4M 3m45s
   100K .......... .......... .......... .......... ..........  0% 34.3M 3m11s
   150K .......... .......... .......... .......... ..........  0% 43.5M 2m47s

511800K .......... .......... .......... .......... .......... 99%  333M 0s
511850K .......... .......... .......... .......... .......... 99%  319M 0s
511900K .......... .......... .......... .......... .......... 99%  261M 0s
511950K .......... .......... .......... .......... ..........100%  306M 0s
512000K                                                       100% 0.00 =14s

2016-12-03 16:33:45 (301 Mb/s) - '/dev/null' saved [524288000/524288000]

 

 

Powerline adapters where to mutch of a haslle. Kept failing when using dew heater controller as it was inteferring (PWM).

With Cat6 I now have 300/300Mb internet in the observatory.

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Hi Magnus,

What a simply fantastic setup you have.

How have you automated getting flats and biases?  Do you just close the observatory lid and film?

Do you know roughly how much it cost excluding optical equipment? It seems I probably need to sell the house to fund something like this.

Regards,

Steve

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9 hours ago, SteveBz said:

Hi Magnus,

What a simply fantastic setup you have.

How have you automated getting flats and biases?  Do you just close the observatory lid and film?

Do you know roughly how much it cost excluding optical equipment? It seems I probably need to sell the house to fund something like this.

Regards,

Steve

Thanks.

The biases and darks I get by closing my remote controlled dust cap :)

I have a A4 led drawing board that I got for flats, but it's not installed yet. It does not turn on when I switch on the powersupply. A button on the board must be pressed, so I have to modify before I will install it. For now I can dither every frame, witch works well. Or I could do sky flats if I get clear skies when twilight.

 

For the price, I have not added all the numbers. It would also be a little confusing as when I order something outside of Norway, I have to add shipping to the price, and then multiply by 1.25x to include taxes.

 

However I have a list of pretty much all items in the obsy! The length of timber purchased I have in a pile of receipts somewhere, and in the cad for the building.

// Teleskope / Mount / Accessories
SkyWatcher Equinoq 80 PRO APO
Celestron AVX
Sky Watcher Field Flattener
Orion Miniguider 9x50
Orion Star Shot Auto Guider
ZWO ASI1600mm-cool
ZWO 7x36mm Electronic Filter Wheel
ZWO 36mm LRGB
Baader HaS2O3
TS 90mm clamps (for telescope)
2x TS Guide rings 34 - 85mm
Dovetail + clamshells (for adjustable base for guide rings)
SW Dowetail (for teleskope)
SW 1.25" LP filter (allready had this, is currently in guide scope)
SW Focus motor
Shoestring focus motor controller
4" + 2x 2" Dew heater strips
Hitec 4 channel dew heater controller

// 8" 'portable' pier
Dan's pier top plates, 8" pier top 
for Celestron AVX inc customization (made pier with 4 rods, so needed 4, not 3 holes in plate)
1x wood hobby plate 1200x620x18mm (cut in half and stacked for pier base)
4x steel angles (normally used for shelves, now casted in to center of pier for added sideways stiffness)
1x 8" cardboard casting tube (main pier structure)
4x 1m m20 threaded rods (for stiffening pier, and anchoring)
2x 25kg weber b30 concrete (used ~30kg for pier)
16x m20 nuts (for anchoring pier to base, and piertop to pier)
Quick matt black spraypaint
Spacked (for pretty pier)

// Observatory building
2"3 treated timber (for most of construction)
2"4 treated timber (for strenghtening of roof support)
2"2 treated timber (for roof structure)
1x 2400x1220x15mm OSB board (for floor and main room / electronics seperator wall)
20x angled holeplates (for observatory structure)
10x straight holeplates (for observatory structure)
12x small angled holeplates (stiffening roof)
Screws short, long, longest (one big box each)
Window rubber seal P (for seal between roof and building)
Primed paneling
Screws for outdoor panel
11x 2cm tick styrofoam plates (for insulation...)
1x roll of 0.2mm tick vapor barrier (for wather proofing)
4x galvaniced hinges (for roof)
Quick matt black spary paint 4x

// Observatory technical
2x 100mm ventilation ducts
100mm 240v ventilation fan for wet room
2x 240v wires (for ventilation fan)
2x Gimson Robotics gla600-s long stroke linear actuators, ink bracets and 12v supply
Odroid C1+
Odroid case
Raspberry Pi 3 Model B
Raspberry Pi case
SanDisk SDHC 16GB UH (system disk for RasPi)
ICY BOX IB-AC611 usb hub (4x output + charge port for powering Raspberry PI)
1x cat6 tp cabel 10m (for internet)
4x cat6 tp cable 1m
1x cat5e tp cable 3m (for dlink camera)
Dlink 1Gb/s eco switch
Dlink DCS-4701EV outdoors IR IP kamera
Linksys PoE Injector (for dlink ip camera)
2x power 'branches' with 6x outputs each
outdoor 5m 240v extension cord with 3x outputs
8 kanals usbrelay (for device power and opening, closing roof)
wiringbox ip67 (for 8 channel usbrelay)
2 channel usbrelay (for swapping polarization to lin actuators)
wiringbox ip67 (for 2 channel usbrelay)
5m dual sided velcro (for cable management)
5m cablecollector
240v exterior push-switch (for manual roof closing)
wiringbox ip67 (for push switch)
2x(red, black) 10m 12v 10A wire

Looking at the list it's no wonder it took some time to assemble :)

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I have been planning to follow @Gonzo with his remote obsy and time has just come free to start work, and now finding your build and such a comprehensive list has made me a really happy man!

You two seem to have struck on a good formula so I'm going to copy it, after all imitation is the greatest form of flattery!

I'm lucky in that my "remote" is just 100m up my garden, next to my workshop which already has power and cat5e running to it.

I will try to distil what I have found both here and in @Gonzo's build and when I post my build perhaps I can advice on anything you have learned that I have missed.

One question for now, whilst I have been in IT for too many years to admit to on here, I last did anything Unix related over 20 years ago, and have never been much of a coder, more databases and SQL, so am a bit daunted by the Linux/Indi elements, so do you have any guidance on getting started?

Best regards,

Ian

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Hi Ian :)

I'm happy to see that you found this thread useful.

A couple things to add after having some experience using the obsy.

1. I should have figured out how to connect my mount to the 'portable' pier before casting it. I could have saved some cash by using the existing pattern for the pier-plate, and not have to get it customized.

2. I made the height of the pier, the obsy walls and the roof so that the entire mount and scope clears the walls. I did this to have a clear view to the horizon, witch I have never needed or used. I would rather make the obsy wall height and the roof 'height' so that the park position of the mount is less critical.

3. The Orion StarShot Autoguider has issues with INDI. I've been planning to replace it, but have not got around to it. Having a autoguider that calibrates on each try, makes a lot of the 'smart' functions of EKOS work a lot better.

 

For starting with linux, I would just get a copy of Ubuntu and install it on a old PC or Laptop to get familiar with setting up and installing INDI.

For later you would most likely like to have it on a raspi, odroid or even a small PC, running just the serverside and no gui, then connect to it from your desktop or so.

The goto page to get everything installed https://indilib.org/forum/general/210-howto-building-latest-libindi-ekos.html

 

Having a obsy makes starting an evening of imaging, and ending it later, SO much more enjoyable. No 30 mins to an hour setting up and calibrating, just booting up and done.

I have the obsy dry enough, that I keep all the gear in during summer, when it's to bright to image anything. All gear looks good, with very little dust at all.

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Hi Magnus, thanks for the input, and now, after a few months working away from home, I'm finally ready to get to work.

This is the real reason I need a remote obsy - I sit in hotel rooms in evenings for months on end in really boring places when I could be logged in and imaging - so the more I think about the build, the more I realise Ineed to consider sensors and automation.

One thing I saw from your parts list is that you have both an Odroid and a Rasp Pi, is this a case of one for Imaging and one for Controlling?

I had planned to build this sky quality monitor to assist with things like the automation of a roll-off roof, based around an Arduino Mega, which looks like I might be able to perform other automation tasks with it:

https://sourceforge.net/projects/arduinomysqmskyqualitymeter/files/mySQMPRO/

But if you have other suggestions or things you have picked up on the way for sensors and automation to enhance the obsy, I'd love to hear about them and include in the design as appropriate.

@Gonzo - Would love your input here too.

Best regards,

Ian

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That’s a really impressive build. Now you say remote set up, but how do you get the lens caps off?

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5 hours ago, MultumInParvo said:

Hi Magnus, thanks for the input, and now, after a few months working away from home, I'm finally ready to get to work.

This is the real reason I need a remote obsy - I sit in hotel rooms in evenings for months on end in really boring places when I could be logged in and imaging - so the more I think about the build, the more I realise Ineed to consider sensors and automation.

One thing I saw from your parts list is that you have both an Odroid and a Rasp Pi, is this a case of one for Imaging and one for Controlling?

I had planned to build this sky quality monitor to assist with things like the automation of a roll-off roof, based around an Arduino Mega, which looks like I might be able to perform other automation tasks with it:

https://sourceforge.net/projects/arduinomysqmskyqualitymeter/files/mySQMPRO/

But if you have other suggestions or things you have picked up on the way for sensors and automation to enhance the obsy, I'd love to hear about them and include in the design as appropriate.

@Gonzo - Would love your input here too.

Best regards,

Ian

Hi Ian.

I use Induino MeteoStation for weather in combination with WounderGroundWeather. Both work with IndiLib

https://indilib.org/support/tutorials/177-howto-configure-compile-wire-print-and-assemble-the-induino-meteostation.html

 

The Odroid I use for imaging and the RasPi does most of controll and GPIO. GPIO support on the Odroid is not as good as the raspi. Also, the raspi has only 100mb/s network. I'm lucky that the observatory has a bandwidth of 300mb/s, so I get the images down faster with the Odroid.

 

8 minutes ago, Marvin Jenkins said:

That’s a really impressive build. Now you say remote set up, but how do you get the lens caps off?

I use this driver https://indilib.org/support/tutorials/165-diy-auto-indi-telescope-cover.html with my 3d printed dustcap. Works quite well :)

https://www.thingiverse.com/thing:2307397

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@MultumInParvo I'll be happy to answer any questions you might have.

Throw them into my build thread please and I'll help you once I'm back in a few days time.

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      Having a drawing of the base in LibreCAD, I printed the drawing 1:1 scale on multiple A4 sheets of paper and glued them together. I transferred the drawing to a piece of cardboard and cut it out.

      Applied this cardboard template to the sheet of plywood, and cut out two parts with a jigsaw.. I’m not an experienced user of jigsaw, and couldn’t manage to cut half-circles accurately enough. Even worse was that the two parts were very different. I didn’t want the frame to randomly tilt left or right when adjusting its altitude, and had to spend a lot of time with sandpaper to make the halves as similar as I could.
       
      Glued the two large parts with three small parts in the middle. Additionally nailed the parts and the base was ready.
       
      Part 3: Frame
      The frame is simply a triangle made of three pieces, with short sides cut at a 30° angle. Most jigsaws can cut at 45°, but not at 30°. Had to buy a new jigsaw with a 30° bevel capacity.
      Cut out three sides, cut short sides at a 30° angle, but didn’t put them together just yet.
      The lens needs to be perfectly aligned with the Sun-facing part of the frame, otherwise the Sun projection isn't circular but elongated.
      My solution was to carve a hole with a little step as shown on the image.

      The inner hole is Ø46.5mm, the outer hole is Ø50.8mm.
      The outer hole is the exact size to let the lens fit, but with a little bit of friction. Had to carve several holes to find the minimal size the lens could fit in.
      The step is just large enough to have enough surface for the glue to keep the lens in place, I didn't want to reduce the aperture too much.
      I used an X-Carve for carving and Easel for modelling.
       
      With all 3 sides ready, I could assemble the frame. It appeared that my 30° angle cuts were not very precise, but after some sandpapering the sides started fitting together alright. Glued the parts together and left them to dry for a day. To apply some pressure on the joints, I wound several twine loops around the frame really tight, made sure all sides fitted well together and left it to dry like that for a day.

      Part 4: Mirrors
      When selecting mirrors I was looking for the smallest mirror that fit the cone of light. Small mirrors are a lot easier to place, and they let me better control the length of the light path. I considered using elliptic mirrors, but they were bulky and really hard to place. All mirrors are first surface mirrors, otherwise planning their locations would be a lot more confusing.
      This was my original plan of placing the mirrors:

      As you can see, all the angles and distances were carefully measured, and I wanted to simply make mirror holders of those exact dimensions. This was clearly a bad idea.
      I 3d-printed some parts like this:

      And only later I realized that the frame angles are not exactly 60°, and that there are drops of glue along the edges that don’t let me fit the pieces deep enough in the joint between the sides.
      I cut angles from all the mirror holders:

      After I put the first mirror in place I realized the angles are all wrong, and that I needed to re-do the holder. Separating the mirror from the holder was a huge pain, which resulted in an accident. The mirror fell off the desk and got damaged.

      Luckily, only the back side got damaged, the front side was still working:

      The final designs of mirror holders looks like this:

      The holes in the front surface let me apply pressure on the back of the mirror if I ever want to separate it from the holder. The recesses collect the excess glue to avoid mirror skewing when gluing them.
      All other holes are simply to save the filament.
       
      Part 5: Placing mirrors
      What I learned is that you can’t plan positions of several pieces with high precision and just hope that it all comes together. I needed a feedback about the precision of mirror positions.
      I used a laser pointer to verify mirror positions at each step.
      In the picture you can see that the laser is firmly set in a hole in another piece of wood, with layers of isolation tape on the tip of the laser pointer to make it stable. A clamp holds the piece of wood in place, ensuring that the laser ray goes in the same direction as a solar ray would. A crosshair of black thread at the center of the lens ensures the laser goes exactly through the center of the lens.


      When placing each mirror, I marked the spot where I expected the laser to end up. While gluing the mirror holder to the frame, I kept the laser as close to that spot as possible. If for some reason, the laser couldn’t hit the expected spot, I did my best with placing the mirror, and recalculated locations of the following mirrors.
      I saw the first sunspots after placing all the mirrors and simply holding an eyepiece in hand.

      Part 6: Eyepiece holder
      I tried eyepieces of different focal length and liked the picture I got with a 10mm eyepiece the most.
      An eyepiece needs to be in a very exact spot to produce a sharp image. At this point it was obvious that my frame doesn’t match the model, and that I didn’t even know what exactly was wrong with the frame. I didn’t want to rely on the model and moved forward with trial-and-error.
      I printed several parts to hold the eyepiece, with different eyepiece locations:

      The part in the photo was a total disaster. It needed quite a lot of filament, at the same didn’t have enough surface area to be glued to the frame, and not enough surface area to hold the eyepiece firmly.
      The next iteration was a lot better:

      This part has a lot more surface area, and needs less filament to be printed. I intentionally printed the hole for the eyepiece too small, and had to sandpaper it a little bit, to make the eyepiece stay firmly fixed.
      Adjusting the focus is done by sliding the eyepiece up and down until the Sun becomes a circle with well defined borders.
       
      Part 7: Dust
      All optical parts should be kept clean. Dust on the mirrors and the lens will make the image darker. Dust on the eyepiece will show up as artifacts on the projected image. Unlike sunspots, the artifacts will not move with the Sun. To clean the eyepiece I used compressed air. To clean the mirrors I used isopropyl alcohol.
       
      Part 8: Fire safety
      Don’t leave devices with magnifying lenses lying around. Once the Sun happened to be in such a spot that its light went right through the lens, burning through the cap of the eyepiece. Luckily, nobody was hurt and no other damage was done.

      Part 9: Future work
      Build quality of the base is very poor. The frame tilts sideways when adjusting its altitude despite all my efforts. I’d like to build a new base, but leave all the work to the machines. I already have a model for an X-Carve to make both base parts, compatible with my current frame:

      A notch along the edge of the half-circle should eliminate the tilt. The precision of the machining should make the base very stable. Maybe next year, when sunspots become a common daily sight, I’ll get to this project.
       
      Thank you for reading this far!
      I hope you enjoyed it.
    • By long_arms
      Hello, 
      It's been a long time since I've posted in this forum, anyway I've picked up a Skywatcher 200p F/6 dobsonian as a DIY project whilst I continue to work on a new telescope from scratch, (I've started to grind the mirror). 
      I'll be making improvements to this dobsonian as a project and learning experience, I've already got a temperature controlled fan which has a probe that can measure both mirror and ambient temperature. I'll be measuring the primary mirror with my in progress Foucault/Ronchi/Bath Tester when that's finished in the next couple of weeks,  may even refigure it depending on results.
      But I'm most excited about this right now. The blackest Black Paint as an alternative (hopefully better alternative) to flocking!
      This stuff is seriously black and flat, I backed it on kickstarter and received 3 bottles along with goodies.
       
      I plan on painting the area opposite the focuser, area around the primary mirror, inside the focuser drawtube, potentially the secondary mirror holder and edge of the secondary also. 
      It's a shame I don't have any flocking to compare it with but it looks incredible. 
      This video shows just how impressive it is (moreso than my little tester I've done).
       
      https://www.youtube.com/watch?v=uJIIzcbRD9w
       
      I'll try and get some decent before and after pics. 
       
      Dan

    • By BLT_Astro
      Hi everybody - I wanted to share my experience of designing and building my own observatory. It is a unique octagonal design and offers pros and cons to more common designs often utilised by the amateur community. If you are considering an observatory project, I hope it gives further inspiration and allows you to find a solution that works for your site, skills, budget and observing aspirations. The story is on my website, link here:
      https://www.bltastro.com
      Clear skies!

    • By Phillips6549
      Tickets (free) are now available for the Birmingham University "Astronomy in the city" event on 6th March.   Sounds like an interesting evening for newcomers like me.
      The agenda includes
      What to see in the sky this month, 
      A talk on super novae
      Ask the experts
      An observing season
      And tea and biscuits! 
      http://www.sr.bham.ac.uk/observatory/astronomyinthecity.php
    • By JemC
      In the famous words of Bilbao Baggins, I'm going on an adventure!
      Almost 2 years ago i got rid of my old shed with the intention of replacing it with a R O R shed, 
      Well a lot has happened since then, but no R O R shed ? No way i could build one, my DIY skills are rubbish.
      My mount and scope plus other bits have sat in the garage ever since, mainly because it's such a pain to drag everything out and set up only to be thwarted by cloud/rain, so i decided that they would stay in the garage until the arrival of R O R shed,
      so fast forward 2 years.....
      Well! while browsing some astro sites i happened across an advertisement which said something like wooden observatory for sale, 7ft x 7.5ft, buyer to dismantle and remove, so me being in need of one had a look at the pictures he posted, that will do nicely i thought, so i contacted the seller and asked for more info and pictures,
      It's not a roof that rolls off onto supports, it turns out 1/2 of the roof rolls over the other 1/2 with a front section of the shed that drops down,
      I was happy with what i received from the seller, he couldn't have been more helpful and seems a really nice bloke, 
      Right then, where are you located mate i asked, 
      Bovey Tracey he replied,
      to be honest, i had never heard of it, so time to consult google maps..
      Well it turns out it's only about 270 miles one way from my house in Lancashire ? (so round trip of approx 540 miles)
      Time to make a decision, do the positives outweigh the negatives, is it going to be a cost effective solution in getting my R O R shed ? 
      after doing some calculations and a little more contact with the seller, the answer to the 2 questions above is YES  ?
      I have hired a box van for this coming Saturday,shangied my brother in law to accompany me and..
      I'm going on an adventure to Bovey Tracy to dismantle it and give it a new home in sunny Lancashire,
      even though my DIY skills are rubbish i feel i have to give this a go,
      All in with the cost of The Obsey (as it is now known until i can think of something better) and with the hire van/fuel and brother in laws dinner
      it's going to set me back approximately £570 and a day out, I'm well chuffed with that, the cheapest quote i had to have one built was £1000
      I have a couple of pictures of the obsey in it's current location if anyone would like to see them,
      Sorry to waffle on so long,
      Thanks for reading
      JemC
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