Hey reddit, I'm the guy who built my own telescope. Here is verification: http://i.imgur.com/EYYRz.jpg?1 and here is another picture for your enjoyment: http://i.imgur.com/nvpRB.jpg?1 Ask me anything!

Comments: 238 • Responses: 46  • Date: 

neural_convergence64 karma

What are you using to account for rotation of the earth to keep the telescope on target for the long exposures?

I am sure there is some sort of product to perform that, but I assume based on the DIY nature of the telescope that you would have done that yourself as well.

That_Telescope_Guy137 karma

The mount has two axis of rotation, one (polar axis) is parallel to the earths rotation axis. There is a motor gear drive that turns this axis one revolution per day in the opposite direction of the earths rotation. This nominally keeps the target stationary for long exposures.

Because of other effects including gravity sag/flexure, alignment errors, and atmospheric refraction tweaking of the drive position is continually needed. When I started this hobby some 30 years ago I looked through a guide scope at a star centered in a cross hair and as it drifted would make small corrections to both axis drives. Now this is done using a guide CCD, and software.

theresaviking21 karma

What got you started 30 years ago?

That_Telescope_Guy59 karma

I've been interested in astronomy since I was a kid. Thirty years ago I was starting to get enough money to do something about it.

neural_convergence14 karma

Follow-up: Is the guide software something your wrote yourself or is it an off-the-shelf product? If the latter, what is it called?

Thanks for replying!

That_Telescope_Guy33 karma

I use CCDOPS for guiding from Santa Barbara Instrument Group (SBIG). You can down load for free from their web site. They make their money selling cameras!

Enursha8 karma

I studied exoplanets at Cal Poly and used CCDOPS as well. Fun stuff!

Edit: Though we mostly used CCDSOFT, a superior piece of software.

That_Telescope_Guy15 karma

CCDOPS is free, CCDSoft I believe has a cost.

FordDent4235 karma

How much computer editing is involved? As in, how closely related is the picture you posted in the post compared to how you actually saw it?

That_Telescope_Guy73 karma

Except for the brightest objects, everything looks like a faint grey smudge by eye, ie colorless. I will typically enhance the saturation to increase the color, and may use other techniques to select only the stars (and or nebula) for enhancement so that the sky background does not become too garish! Separately I try to force the sky to a neutral color, not the muddy brown it would otherwise look.

The images are exposed for up to several hours, then forced brighter using a variety of software. I break the total exposure down into 10 minute sub exposures.

Bottom line there is a lot of image manipulation that goes on in producing a single image.

FordDent421 karma

If I were to actually go to that place in space, would I see the grey or is that becuase of how many lightyears it is away? And for an aspiring stargazer, what entry based telescope would you advise I get?

That_Telescope_Guy1 karma

Visit a public observatory, understand what you want to do. Build up from a modest start.

Visual astronomy is great for a modest set of targets, but.... many great objects photographed, are almost invisible visually. Moon, Pleiades cluster, planets, globulars and some more are fine visually. Many nebula cannot be seen in a telescope by eye unless you have the patience of a saint!

MrGulio34 karma

Your work is extremely impressive and inspiring. Please please please post a detailed set of instructions on how you did it and a break down of the costs.

That_Telescope_Guy77 karma

The detailed of instructions would take many pages, I will find/post some references that provide the basic information.

As for cost, the hobby at my level is not cheap. The mount is the single most expensive part of the system.My mount is an Astro Physics "1200GTO" which no longer made. The size smaller 900GTO today is $8750, the size larger 1600GTO today is $11500. I believe 10 or more years ago I paid less than $10K for the mount. The telescope itself consists of a purchased mirror and home made truss and support structure. Everything is probably $5K. The imaging cameras are in the $5K range The observatory is very homemade and about $1000 in lumber and concrete. It is called sweat equity. There are many other bits and pieces some made on my lathe some purchased. There is also software some free, some purchased.

All the above being said, I started with a Celestron C8 and low cost mount 25 years ago for of order $1000. The hobby has grown over the decades, not as suddenly dumping 20K in stuff and having a go at it.

LarrySportello17 karma

Did you have to remove the IR filter on your camera to get pictures of the nebulas?

Did you build your own equitorial mount as well?

That_Telescope_Guy44 karma

If you use a conventional "SLR daylight camera" like a Cannon or Nikon etc there is a red cutoff filter that dramatically reduces the astronomical H-alpha wavelength where much nebula detail and color is. I did start taking pictures with a SLR but left the filter in. I now have CCD imagers made for astro-photography that do not have the IR filter.

I would personally be reluctant to remove the IR filter myself for fear of screwing up and destroying the camera.

poonjab92021 karma

Man builds his own bad ass telescope...

Scared to take apart a camera. Does anybody else find this particularly amusing?

That_Telescope_Guy40 karma

Camera has very small parts with very tight tolerances. Easy to screw up.

That_Telescope_Guy3 karma

Your sarcasm matches mine. Love it!

dcux6 karma

Just how far have astro ccds come? When I was really into backyard astronomy ccds were just becoming available and required cooling units to work well. They were also quite expensive.

Thanks for posting. I may just have to break out my 8" SCT again soon. If only I had a static location and dark skies (middle of a huge urban light pollution hole).

That_Telescope_Guy13 karma

CCD cameras are excellent, can cool 35 deg below ambient and lower with water assist. Low noise, and straight forward operation. They come at all price points, from many hundreds to tens of thousands of dollars. One thought if you have a SLR, experiment with that before jumping into more expensive equipment. With Photoshop, maybe even Photoshop elements it is possible to suppress the sky background to an amazing degree.

Shadow7037932 karma

Regarding cooling, are you using a TEC at all? Considered using a TEC? TECs are pretty cheap but the power supplies are a bit expensive, HOWEVER you can modify a decent PC PSU like a Corsair 450W pretty easily.

That_Telescope_Guy1 karma

Like the previous conversations about removing an IR filter in a SLR camera (I know optics, electronics got to be simple) the imagers I now have all have built in cooling.

pimpin8ez16 karma

Where about do you live? I would imagine somewhere far from light pollution?

That_Telescope_Guy27 karma

I live in Fairfield County Connecticut. The light pollution here is bad. On good nights the milky way can be easily seen, but often it is just a faint smudge.

Harlestone2 karma

is your telescope portable, or could it be with a lot of effort?

That_Telescope_Guy2 karma

I did portable in by early life, pain in butte?!!!. Fixed observatory a compromise, but worth it!

veeshan16 karma

what inspired you to build it, and how what's the longest session you've had with ur telescope. Also, can i borrow ?

That_Telescope_Guy28 karma

I have been interested in astronomy since my pre teen years. As a result of my interest I became an engineer and have worked at designing and developing telescopes for over 40 years now. The largest I personally worked on is a 4+ meter aperture telescope in the Andes in Chile. I got to go there for the dedication. The longest "photographic" or imaging session to date spanned two nights and lasted for ~8 hours.

rationalgia2 karma

Was your interest in astronomy or rather astrophotography? I too had an interest in astronomy and started out going to star parties and doing the amateur astronomer thing. For me, the only natural path to follow an interest in astronomy was to go back to school to study astronomy (though I later left the field and worked as a spacecraft controller). What made you choose engineering over astronomy?

That_Telescope_Guy3 karma

I cut lawn for a professor ( don't remember where) I wanted to be a "scientist" he pointed out to my parents that this was a 1% of 1% field. to make a good living!!

Math, Physics, and a scholarship lead me to engineering.

My dad was an artist! Go figure!

ivarneli1 karma

Can you share which 4m telescope you worked with? Earlier this month I was working on Cerro Tololo in Chile and visited the Blanco and SOAR telescopes, which I think comprise 2/3rds of the 4m class telescopes in that country.

That_Telescope_Guy1 karma

It was SOAR.

SeattExPat14 karma

That is a beautiful machine.

Is it a reflector or a refractor? It's hard to tell from the pictures. Also, I would love to know the objective diameter and focal length, please. If you could give us an idea on eyepiece magnification as well, that would be swell.

That_Telescope_Guy15 karma

The large telescope is a Newtonian Reflector. It is 16 inch aperture, and 72 inch focal length. The smaller "Guide telescope" can also be used for imaging is a 4 inch aperture refractor.

I do not ordinarily look thru the telescope preferring to take images. The eyepiece is about 8 ft off the floor when looking up and it is quite dangerous at night to be up there. However if one used a 1/2 inch focal length eyepiece the magnification would be 144X.

xertal11 karma

How long did it take to build the telescope and how much money did you spend? Also why did you decide to built your own telescope instead of buying a preassembled one? Finally please post more pics ;)

That_Telescope_Guy13 karma

I gave a rough cost earlier. I built my own to save some money. An equivalent finished scope to mine would cost over $15K more than my cost. And I'd miss out on the fun of building it.

uberphat8 karma

Can you post the specs of your telescope please.

That_Telescope_Guy9 karma

Newtonian, 16 inch aperture, 72 inch focal length.

donrhummy5 karma

What do you do for a living?

That_Telescope_Guy11 karma

My education is Mechanical Engineer, over the years I "graduated" to what is called Systems Engineer.

donrhummy4 karma

How does it compare to the telescopes used by NASA and astrophysicists?

That_Telescope_Guy4 karma

Generally it is smaller, less sophisticated, and cheaper. BUT depending on the "mission" some of their hardware is quite small compared to my large scope.

ScottFromCanada4 karma

Can you explain image stacking a bit? I just started using Registax and haven't had much luck so far. The only thing I've read so far is that stacking can be good for cancelling out the camera noise, but does it also make the image brighter? Thanks!

That_Telescope_Guy5 karma

You have not said what kind of images you are taking. Registax and a similar group of free software is generally used for stacking video where hundreds of images are taken over a few tens of seconds. Think planets, moon, or sun. I have never tried these on a classic astrophoto with stars and dim nebula. Where I have 10 to 20 images of faint fuzzys I use Mike Unsolds "Images Plus" for both taking the exposure and initial stacking and processing. CCDOPS may have the same capability but probably only for SBIG cameras.

samtheonionman4 karma

Have you always been interested in astronomy? Why did you want to build this? Was it difficult to build?

That_Telescope_Guy6 karma

See previous answer for part 1 and 2. Building the telescope was not difficult in any classical sense of hard work. It did require a lot of thinking what kind of telescope did I really want and what was I going to do with it. I personally have had 3-4 telescopes over my life and those experiences helped me decide on this one. The building did require about 6 months of calendar time, to complete.

cbass4114 karma

Did you get any shots of Venus, Jupiter, or the transition of Venus this year?

Also, what is a decent, entry level telescope that someone on a budget could purchase?

That_Telescope_Guy8 karma

I wanted to photograph the Venus transit and set up a small telescope in the part of my yard with a good western view. It was cloudy and I got nothing. Late in ther transit I jumped in the car and drove around and found a clear spot where I could briefly see the transit in binoculars.

I have some shots of the solar system objects which I will post. Most are taken with other telescopes.

I would not give specific telescope recommendations, however a magazine like Sky and Telescope often has reviews of equipment at different price points. You might even ber able to see past reviews on their web site.

Years ago I took decent photos by plopping my film camera with a mild telephoto lens on a cheap motorized mount and exposing for 1/2 hour.

PeacockDoom3 karma

Where would I go if I wanted to purchase the right optical equipment to do this myself?

That_Telescope_Guy4 karma

I'd start by looking at something like Sky and Telescope, or Astronomy magazine; and when I started I would jump in slowly.

Yianna2 karma

i Always Loved astronomy But i live near cologne and i can only see the birghtest stars and Telescopes are very expensive (at least in germany). Do you think it's still worth a try ?

That_Telescope_Guy4 karma

It is probably worth a try, but go slow. Is there a public observatory nearby who might let you hang a camera on their telescope?

A thought.

That_Telescope_Guy2 karma

Here is a link to three pictures of the sun taken Aug 31. They are taken in hydrogen alpha light using a very narrow band filter.

The first is a full disk, with an inset showing the identification of each sunspot. The next two are closeups of specific subregions. http://imgur.com/a/puTx2

RockyPowPow2 karma

What do you do for a living? Did your profession parlay into this grand hobby?

Elevation where you live?

Do you plan on making further improvements to it so that it can do more than what it is doing now? If so, what else are you hoping to add?

That_Telescope_Guy8 karma

See above for profession, yes my profession and hobby do complement each other very much.

Improvements yes, always, this is the world of continuous improvement! Specifically I would like to do more narrow band imaging, that gives very dramatic color.

_shnazzy2 karma

So, you seem to know stuff about telescopes. Hypothetically, if I were a budding amateur astronomer looking to buy my first entry level awesome telescope to see stuff far away with, what would you recommend? Without a budget in mind, just a general biggest-bang-for-your-buck sort of idea.

Your photographs are beautiful.

That_Telescope_Guy3 karma

You know all this interest is blowing me away. I really cannot recommend anything specific. There is much good out there! My advice is start modest, when I started, a big frustration was just finding the target object. When I finally saw M51 (whirlpool galaxy ) by eye as a faint fuzzy I thought this was great but this is one of the brighter galaxy's. My thought is get a dual use instrument. Binoculars have always been recommended. A 3" class refactor is good on many solar system objects, and some deep space stuff. With a tracking mount and a camera with time exposure, you can get decent images.

Build from there. People think I have a huge investment in this equipment. I do! But it was done over pay as you go decades, with a developing confidence I would keep at it.

The point is you can invest many dollars and decide to give it up. Then $ wasted!

mykchap2 karma

My question is can you upload more and more awesome photos from time to time if you manage to capture some? Please?

That_Telescope_Guy2 karma

right nowit is full moon, a bad time for good images. I do maintenance, and... after I get them processed solar (sun or daystar) images) Will post in next day so!!!

That_Telescope_Guy2 karma

If this works out I am posting a link to an album of 3 images ov the Veil Nebula East taken early in Aug 2012 (around the 2 or 3) showing what happens before and after editing.


First is the heavily processed final sum of 9 images each of 10 minute exposure, then a single 10 minute (600 seconds) exposure with no brightening, and last after doing a levels brightening of the single exposure.

unsieved2 karma

How do you manage and backup all the data you acquired?

That_Telescope_Guy4 karma

Lets face it, back up on 2 disks in house. The world is risky.

IWontSayIt1 karma

How did you do it? (in less than 10 words)

That_Telescope_Guy3 karma

accept failure, learn from mistakes, self reliance, know your gut!

counts as 10 words!!!

mardob1 karma

What will be your next quest? Your next mission? Got something else going on in the garage?

That_Telescope_Guy1 karma

Solar! Helps during summer when the nights are short!!!!

nhilante1 karma

I always have a humidity problem resulting in atleast an hour of waiting before i can use the scope when i place it outside. How did you manage to overcome that with that homemade shack? or is it not a problem there?

That_Telescope_Guy2 karma

Big problem, many parts of the solution. Basically, cover parts to achieve minal sky exposure. Of course you need the path to the target under observation. Key is drying the air near optics by the cooled CCD when the humidity is high.

shoganaiyo1 karma

Is the telescope mobile? Could you transport it to a different location for better viewing?

That_Telescope_Guy2 karma

No way. The advantage of a home observatory is you do not have to take it down if the local forecast is rain!!!

uncreative11 karma


That_Telescope_Guy1 karma

I actively track but mount is pretty good up to several minutes, what is IRAF.

attax1 karma

So, I studied astronomy for a few years before pursuing Chemistry instead. This is fascinating to me, but my biggest question is what did you do for the glass? Did you order it yourself or make it yourself? IF you made it, how did you do it?!

That_Telescope_Guy3 karma

For the 16 inch Newtonian, the mirror maker was Pegasus. My opinion, adequate, but not up to his claim. That being said, I would likely go to him again.

itaremeelar1 karma

How would you recommend going about building a telescope? I know how they work and such (intended astronomy/astrophysics major), but I was wondering what the process is like. Fun? Tedious? Certainly rewarding, yes?

That_Telescope_Guy1 karma

Rewarding .... yes. Potential for being sent to an anger management class... also yes. Start modest, relish success, learn from failure. You'll get there.

Start too ambitious and you will need to start over!

dirtymoney1 karma

How does it do on closer celestial objects, like within our solar system? Got any pics of jupiter?

That_Telescope_Guy1 karma

My 16 inch is set up for deep sky. I am getting some images together from my 4" solar scope, which include local objects (solar system) and the sun. This is another dimension of my hobby!

nrock22561 karma


That_Telescope_Guy1 karma

First name is Conrad!

kbakes10201 karma

Could you post a photo before editing and after editing? Would be very interesting to see a side by side comparison.

That_Telescope_Guy2 karma

Great idea!

Not quite as simple as it sounds, because almost all digital images , even straight out of camera have "editing". Let me work on the thought you are expressing and see what I get.

seeteethree1 karma

In 1958 my wife's father built a 14 inch reflective telescope; ground his own mirrors, and built a clockworks using the motor from a table fan. Still in the backyard.

That_Telescope_Guy1 karma

Is/was it used.

My comment is based on the reality that a smaller scope used often became my objective. Until I built the observatory it was a pain to set everything up, and have a cloudy night.

SeaLeggs0 karma

How many boobies have you seen through it, excluding Mrs That-Telescope-Guy's?

That_Telescope_Guy2 karma

Now none, as a kid no comment!!!

Zaydene0 karma

My father makes telescopes as well.

Did you build any custom machinery to help you build? A kiln, vacuum chamber, grinding machine; or did you outsource most of your stuff?

That_Telescope_Guy1 karma

Fixtures yes, lathes, drill presses, etc no.