Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

stargazine_ep14_banner.thumb.jpg.27eb9b06c9c8a1fe5ac3bae21c92743b.jpg

Stargazer33

Lightbox for taking Flats

Recommended Posts

I've finally got around to making my flats box.

I decided to go for a cylinder rather than the normal square as I thought it would maximize the amount of reflected light and limit any 'dead' areas. I could also use the Celestrons dust cap retaining pins to lock the flats box onto the 'scope.

I purchased some of the craft board that has a thin foam sheet sandwiched between two sheets of thick paper/thin card. In order to bend the card into a cylinder, I creased the board every 20 mm by pressing the edge of a steel ruler into the board. It took two of the sheets to make a cylinder big enough to fit my C9.25, with only a couple of cm trimmed off.

   IMG_20191230_161223.thumb.jpg.007212d56aa8f0a4a3f7f05e033352ec.jpg  IMG_20191230_161129.thumb.jpg.451655123f8cb94e3bcaf5b712e7f9d9.jpg  IMG_20191230_161034.thumb.jpg.db398c709038585141f7c179d9b28831.jpg

 

I then made a reinforcing ring/defuser holder from two strips of the foam board; this time creasing them at 15mm intervals. I stuck these level to the bottom edge so the joins were 90° to the main cylinder joins. These strips were cut wide enough to ensure that the diffuser cleared the secondary housing.

IMG_20191230_161300.thumb.jpg.165c3b10097043989b438c6b785356d0.jpg  IMG_20191230_225442.thumb.jpg.faec62ac72e41ae12daea6052a1dc5ad.jpg

 

The cylinder was designed to lock into the C9.25s dust cap retaining pins so next I cut two keyways into the bottom outer side. They looked a little weak so I reinforced them with some Christmas chocolate reindeer plastic packaging!

 IMG_20191230_160952.thumb.jpg.57fcdc99266524b43ee5b56f4d8967b9.jpg

 

Although the foamboard is quite shiny, I wasn't happy with all the grooves, so I lined the inside with white A4 paper. The Perspex sheet was cut to shape and hot glued into place onto the ledge.

IMG_20191230_162024.thumb.jpg.0fa4322c767ea3a1f33214bc35616108.jpg  IMG_20191230_161949.thumb.jpg.328762bbf6af4e2017dc5437b98d1e49.jpg

 

Next, starting at the top, I notched the edge of the cylinder to run the LED string lights cable through and then started to spiral the LEDs around and down the cylinder.

IMG_20191230_230932.thumb.jpg.8a7b97a7d069a61cfb391ab72e0fe23e.jpg  IMG_20191230_161841.thumb.jpg.f6099780cdc354df77cc03a5326cc79a.jpg

 

The top cap/reflector was made from two discs of foamboard. One to go inside the cylinder and one to sit proud of the edge. They were glued together before being hot glued onto the top of the cylinder. The LED light string that I bought has an integrated on/off button as well as both up and down brightness buttons with a 3M sticky pad on the back, so I stuck this to the top cap.

IMG_20191230_161621.thumb.jpg.119dac7a772157089617dd988829ecde.jpg

 

As I had previously made myself a 'scope mounted power distribution box with aircraft sockets for power, I removed the 3 pin UK plug/ac-dc converter and soldered on an aircraft plug to match my 12 volt DC supply socket.

IMG_20191230_161426.thumb.jpg.806f7c1e4232d01797f271e24af4d385.jpg  IMG_20191230_161737.thumb.jpg.212f3c86489bc522420c596c7cdf6a46.jpg

 

The lightbox illuminated.

IMG_20191230_161809.thumb.jpg.4c42eb8a1cfac719471f1e197f9e596f.jpg

 

Edited by Stargazer33
Stray picture removed!
  • Like 2

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By astrosathya
      Hi Everyone,
      I am thinking of re-starting mirror grinding at home. I used to grind by hand and in this method, when we use the 1/3rd off-centre strokes for hogging out the sagitta, the upper glass becomes concave and would be polished into a mirror. 
      However, this time I'd like to build a Mirror-O-Matic or something similar and do not understand that if the tool is on top, how will the bottom glass become concave? 
      Or am I mistaken?
      Please advice.
       
    • By astrosathya
      Friends, I am back with a tutorial video on how to modify your Sky Watcher HEQ5-PRO mount or its American twin, the Orion Sirius EQ-G into a belt driven mount.
      The benefits of converting to a belt drive is that you don't have to worry about Backlash. The procedure took me about an hour to complete.
      Link is below
      https://youtu.be/PjDZiXaN5KM
    • By feverdreamer1
      Hi,
      As a newbie in AP I recently discovered that astro imaging isn't as simple as I imagined, it's not just "pointing and shooting".
      The main point is that I need a tracker that will follow the sky's movement. But after seeing the prices at which decent trackers are sold I decided to see if I could build one myself from spare parts at my workshop. Turns out that I can, using two planks of wood a hinge, an arduino, a stepper motor, etc. So I decided to get to it, I have built the connection between both planks of wood with the hinge, but have now discovered a problem. After some investigation, I realized it's quite commonly named the "Tangent Problem" (the rod forms a 90º angle with the bottom plank). So the solutions offered vary from curved rods to involute pieces of plastic and tilting the rod.
      I also saw another solution that was adjusting the speed at which the rod moves, and since I'm going to be using an arduino-driven stepper motor, I decided that this was the way to go. The problem is that I don't know in what ratio the speed has to increase over time to compensate the "Tangent problem".
      That's why I decided to pose my question here as I'm sure someone must have done it already.
      Sorry for my bad english, it isn't my first langnuage.
      Thanks in advance and clear skies,
      S
    • By FranTeryda
      Hi! I really want to get into watching the night sky. After a looking at the scopes that are available in my country, I chose to buy a SW Explorer 200P (haven't yet) and build a homemade dobsonian base. 
      I really like the aesthetics of the Orion Sky-quest dobsonian bases, so I draw a really similar design to fit the SW scope I want to buy. But while drawing it, I had tons of questions and I hope you can help me. 
      First of all, I just could get some aproximate measures of the parts of the scope out of the internet. If any of you has one of these SW reflectors, I would really appreciate if you can take some measurements for me to make the design more precise.  Specially I really need the thickness and size of the holes of the rings.
      About the bearing surfaces, I can't get anywhere the Teflon pads you usually use. What can I use to replace them? Also, what about the radius of the altitude bearings, Is it important? 
      Finally, which should be the height of a dobsonian mount? I don't want to be bent over to be able to see comfortably, nor I want it to be  too tall. Is it supposed to be used on a stool or something?

      I will really appreciate any other tip you can give me. I have never had a telescope, neither have I seen a dob mount. So I can be making a big mistake trying to convert this OTA to use with a dobsonian mount. 
      Anyway thank you very much. Cheers from Argentina
      Almost forgot to add some pics of the 3D design I made! 

    • By RH323
      I'm fairly new and on one of my daily stargazing sessions I viewed, with the naked eye, a huge passing light going SE, from my perspective it was brighter and bigger than any stars, planets or meteors that I've seen before. It was roughly the size of a baseball. 
      If this was a star -> . 
      this is roughly how big it looked -> O
      It had a trail of similar size, seemingly dusty. It also passed and disappeared between Corona Borealis and one of Hercules' legs. 
      Viewed on May 16th, 22:00- 23:40 
       
      I assumed, based on recent headlines, that it was Comet Swan, but upon further investigation, that was far from true. 
      Comet Swan should not be visible with the naked eye, and definitely not to the degree I saw. Additionally, based on my coordinates* it wouldn't even cross the sky I saw, it would be below the horizon. 
      (*roughly 15 °N, 120 °E, PH)
       
      Considering again the magnitude of the object amd the fact that I viewed it with the naked eye discounts it from being an asteroid or meteor*. 
      (*More possible but still hard to believe with its size, you wouldn't even see something like that during meteor showers)
       
      So I then researched if it could be space debris. I thought that something as big as that should be covered by a news article somewhere. 
      *The only results were of the 18 ton Chinese Rocket but it couldn't be that because:
      A. It passed over Los Angeles and New York then fell into the Atlantic Ocean, with some pieces landing in Africa. Meaning it wouldn't pass over my country.
      B. That happened 5 days before my viewing, on May 11 at 11:33 AM ET (08:33 PDT)
       
      It's still possible but it just seems unlikely, and with how big it was I'd assume that it would attract some media attention but I cant find anything else. 
      Does anyone have any idea what it could have been? I have to know. If it was debris then all I need is confirmation.  
       
      *
      https://www.google.com/amp/s/www.cnbc.com/amp/2020/05/16/chinese-rocket-falls-to-earth-space-debris-problem-worsens.html
      https://www.google.com/amp/s/www.theverge.com/platform/amp/2020/5/13/21256484/china-rocket-debris-africa-uncontrolled-reentry-long-march-5b
       
       
       
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.