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3D Printed Spectrascope- Ian Tracey

So you want to make a spectroscope, eh? And you want to 3d print it too? Well, this guide’s for you.

How to 3d print a spectroscope.

First off, we must define what exactly a spectroscope is. defines it as [A device] used to split light into various wavelengths...also used to help astronomers identify the motion, temperature and structure of celestial objects.”
Now that you’ve got a good idea of what a spectroscope is, let’s get ready to make one.
Go to TinkerCAD is a very helpful program that lets you design a 3d model, and export it to a slicer (we’ll discuss this later). An example screenshot is shown below.

Screenshot 2016-12-07 at 5.58.01 PM.png

You should create an account and then take the tutorial provided. You don’t have to do all of it, just do enough until you feel comfortable using the program. Next, you should take take a look at my spectroscope design, and tinker it a bit. Try ungrouping the whole design, and see how the whole thing was put together. Here’s the link for it...

Now that you’ve goofed with my design, I’ll show you how to make a very basic spectroscope. Once you complete this design, you can print it, or add on to it. Anyway, let’s get to it. Just follow my steps, and you’ll be ok.

  1. Open up a new design on tinkercad
  2. Drag a box onto the Workplane
  3. Stretch it out to the dimension of 75x42x4mm (LxWxH)
  4. Add another box.
  5. Make the dimesions 30x30x95mm
  6. Make the angle 45ยบ and put it  the middle of the other box. It doesn’t have to be blue, I just did this to make it easier to see.

  1. Add a hollow box on the bottom to get rid of the excess blue box from step 6.

  1. Now move the workplane to the top of the blue box.
  2. Duplicate the blue box. Make it hollow, and make its size 28x28x100. Make sure it’s centered with the blue box.
  3. Now, push the hollow box until it is a few (1-3) millimeters within the blue box. You can tell when you’ve done this when you can only see the blue box.
11) Add another hollow box. Make its dimensions 2x20x8 mm. Place it a 6 millimeters within the blue box.
12) Now group it all together.
13) Move the workplane back to its original position.
14) Off to the side of this design, make a box with dimensions 36x28x4mm.
15) Now add a hollow box (10x19x11) within the green one. Place it near the middle.
16) Group the two together. Place them in the hole at the bottom of the original design.
17) Now group everything together. Congratulations, you just made your first spectroscope! Now, you can either add more onto this basic design or print it out.

  1. Ok, so now that you’ve finished your design on TinkerCAD, you’ve got to download it. Go to design, download, and download as “.stl”.
  2. Now you have to get a Slicer program. This is a program that allows you to transfer your design from TinkerCAD, and actually print it out in real life! “Cura” is the best Slicer program that I’ve found, so go google and download it. Note: This program won’t work on a chromebook!
  3. You should import your design now. Do this by going to file, then import your design. Make sure that when your design is yellow, and not grey- this will ensure that it will fit on the 3d printer!
  4. Now, you can download it. Click “download to SD” in the top left corner. A notification will appear on the bottom of the screen. Click it, and eject the card.

The cura program is shown above.


Finally, we’re at the good part!

  1. Your design is ready to be printed now. Let’s do it! Place the SD card into the machine (located on the right side). Push it in until it clicks.
  2. Level the plate. Hit “move”, then “home axis”. Use a wrench or whatever to make sure that the plate is about uniformly level- you should be able to slide a piece of paper around with a little resistance.
  3. Now, let’s print it! Go to “print”, then choose your design. It’ll probably take a few hours, so get get a snack and wait until its done. However, you should check on it from time to time to make sure nothing goes wrong.
  4. It’s finished! Congratulations, you just 3d printed your first Spectroscope!

How to Use Polarr image editing- Guest blogger Ian Tracey

Let’s take this image, for example. It’s black and white, rather boring… Wouldn’t it be better if it was in color? This would allow us to see the galaxy better- and in its true

To start, we’ve got to download Polarr. Google “Chrome store”, and type in the search bar “Polarr image editor”. Scroll down until you see it listed under “apps”. Then, click ‘add to Chrome’, and wait for it to download.

Launch Polarr. In the top left corner, you’ll see this symbol.
Click on it, and upload the image you selected to enhance.
Now that you’ve got your image uploaded, you should see this menu bar on the right, with these symbols on it.

Click on the second one from the top- it looks like a cooking timer. It’ll bring up another menu, looking like this...
Click on the one that says color. This menu will pop up.

Try adjusting some of the values, such as the one for temperature. You’ll notice that it changes the color of the image! Keep playing around with these values until you get the image to look more colorful and vibrant, like the image below.
Next, let’s look at the tab for Light. It’s under the one for Color. There are many effects you can play around with, but let’s just look at Exposure, for example.

This will change the amount of brightness in your picture. But- be careful- too much, and you can make your image so bright, it’s difficult to look at! And if you make it too dim, it will be very difficult to tell what your image is.

Finally, let’s look for the Details tab- it’s right under the one for Light. Try some of these effects. Mess around with the clarity, try to make the image pop out more. Use sharpen too, but don’t overdo it- or else the image will be grainy.

You needn’t worry about the other features of this app, unless you really want to use them. They’re mostly just for fun. But anyway, let’s have a look at the starting and finished product.

I used a few distortion effects on this one. If you want to, you can, too. It’s a few buttons below the Details one.

I hope you phare well with your photo-editing process!

New and improved video projector for my super cheap, but great planetarium

If you've followed this blog for the past several years, you may remember that I have a planetarium where I teach. It was built in 1987, from equipment made in 1961. In 87, that made sense. There were no big developments in projection, so an old, quirky Spitz Nova III with a massive Spitz A3P console and soundboard (I have no idea why. I think Spitz just wanted to get rid of it) worked fine. Fast forward to the 21st Century, and we have kids that are no longer impressed with little white dots on the ceiling, and all of the production companies went digital. In 1998, when I took over, the amount of work that went into maintaining the equipment, creating, setting up, and putting on a show, was daunting.

     Over the years, I became a pretty good engineer, rigger, welder, and scavenger. But, the kids were no longer impressed, and if you're a teacher, you know that there has to be some level of entertainment. The cost of cool, however, was too much. I looked for options, and I found one. An LCD projector bouncing off a $25 curved security mirror. The results were a little underwhelming, but acceptable. Using Stellarium, and Celestia brought astronomy back to life in an old, obsolete planetarium.

     I was okay with what I had, but a VGA projector does an okay job, but the new 4K, and soon 8K projectors will certainly rock the house. For now, I will settle with my new HD NEC

All of the following images are cellphone captures

Dark Sky Photography with my new (to me) Panasonic LX-3

Being an astronomy teacher, I am always asked how to take great astrophotos. I really have no idea, but I am always willing to learn. The only option I have to take dark sky images is my favorite camera, and the greatest camera ever built, a Pentax K1000. I love that thing, and it takes amazing photos, but being that it uses film, and my inability to wait patiently for results, I never considered using it for night sky applications. Digital is the way to go, but the teacher part of my title means that I can't drop $1000 on that specific application. I started reading forums about point and shoot cameras that take great images in the dark. The Panasonic LX series seemed to be a stand out. My price range under $100, and Ebay came through. I picked up a loved (aka beat) but functional LX3 body, with a clean lens for $80 after shipping. Here are the first few shots.
A random tree 60 minutes after sunset

Zoomed in on Orion

Constellation of Taurus

Injury Report App Form Setup

Thank you for downloading the App. I hope you find it useful. It's not ready to go right out of the box. You will need to set up your Form page using your computer tablet or phone. The Form page allows you to enter data, and store it securely. Once you have the app, you'll need the Form to add to it. It will be stored, and since it's web based, any changes you make to the Form will be made in the App.

Here is the Form page. Open it and
I know this sounds like a pain, but it helps in keeping the Form from being destroyed by kids

 Please follow the next set of instructions carefully. This form is a live form. That means that any data you add, or changes you make will be saved on my copy. Please copy the form before doing anything else. If you find that the page has been altered, let me know ASAP so I can fix it

From the File Menu, Make a Copy

Change the Document name to make it easy to identify. In order to keep the data private, be sure you do not share it with anyone.

Your new Form should now be available for you to Edit and Use

The next part is easy. Select View Live Form

Paste the address in the app, or use it as is for reporting Injuries in a spreadsheet on your computer,

Be sure to test it out, and double check your privacy/share settings on your form

My next post will help you convert the spreadsheet into a report document

Another Action Cam Comparison 1080 GoPro Hero vs 1080 No Name Clone

Why stop with one Chinese GoPro knock-off, when you can have 2 at a forth the price. My last review was a head to head comparison of a 720p Action Cam I bought on Ebay for $32, and the new GoPro Hero. The 720 is a nice cam, and I'm happy with the cost/results, but the narrow field of view was a turn off. As a car dash cam, I think it's a nice option. Now, Ebay also sells 1080p cams for around $50, so I think that this resolution comparison would be more apples to apples. This new cam has lots of extra features that the $129 GoPro Hero lacks. Multiple time-lapse options, and wifi are the two I liked the best. Since I don't own other GoPro cameras (3, 3+, White, Black, 4, Etc) I'm not sure what this clone is made to compete with. But, based on price, you can buy 2 of these cams, with tons of accessories, and still have $20 in your pocket when thinking about the Hero.
$129+tax  Hero vs $54 free shipping Ebay SJ400 clone
Let there be no doubt, I love my Hero. It's simple, to the point, and gives amazing results. I am only looking at low cost options, that give a high level of price/result ratio. You may be curious, broke, on a tight budget, or be considering buying a $400 GoPro, but don't know if it's worth the cost. I think that dropping $50 on a nice quality cam that you never use, is better than doing the same for a $400 one.


The clone has wifi that connects to your phone, or tablet (Android specific?) via an app called iSmart DV

Having the wifi, and the LCD screen is a real plus when centering and leveling the camera. I have found it useful when I mounting the cam on my bike, outside, or in a spot with a tight fit. This a nice, but not a necessary option. The wide field of view on these cameras, makes it a point at anything and it will be in the shot camera.


Clone Time-Lapse The poor quality is due to YouTube compression . The actual video is HD

The time-lapse feature on both cams is really fun to play around with. The clone gives you several options beginning with 2 seconds and going to 60. 5 second interval is great for fast clouds, 10 for slow, and the rest is to experiment with. 60 would probably do well with flowers blooming. The GoPro Hero does it only at .5 seconds, which is ideal for fast moving objects.

The Hero excels at time-lapse. The SJ4000 clone can't do the .5 sec
GoPro Hero (the quality is reduced by YouTube processing)

I will post a side by side video as soon I get time to play. For now I'll keep them both with me