Afocal Astrophotography (is really simple)!
What follows is an afocal
astrophotograph I took of Saturn. Afocal astrophotograph is a fancy term for
just sticking a camera up to where you normally put your eye to look through
the telescope. Afocal: just held up to the regular eyepiece of a telescope, or
microscope or binoculars. Astrophotography: when you aim at something in the
sky that isn’t a bird or plane. It’s that simple!
Here is the resulting photography through my 8” Zhumell reflector (mirror, not lens) Dobsonian (mounted on a lazy-susan swivel) telescope. I was using a high magnification eyepiece. I think it was my 3mm Zhumell Planetary eyepiece. That’s why it’s dark and kind of fuzzy. The smaller the mm number in a telescope eyepiece: the higher the magnification (zoom in) but the less light and less sharpness you’ll get:
Here is the resulting photography through my 8” Zhumell reflector (mirror, not lens) Dobsonian (mounted on a lazy-susan swivel) telescope. I was using a high magnification eyepiece. I think it was my 3mm Zhumell Planetary eyepiece. That’s why it’s dark and kind of fuzzy. The smaller the mm number in a telescope eyepiece: the higher the magnification (zoom in) but the less light and less sharpness you’ll get:
And that photo above (on a 19" screen) is about as small, but crisp as it was looking with my eyeball through the telescope too! Depending where Saturn is in relationship to earth the rings can be edge-on and almost invisible or more titled so we can see them better. Also, Saturn and all the other planets change in apparent size depending on time of year and how close/far they are from planet Earth.
Later, I took around 10 seconds of jittery, crappy hand-held
video and then registered (lined up) and stacked (piled on top of each other) the
resulting video frames using RegiStax. RegiStax is a FREE awesome
astrophotography program. It took me about 4 hours to download and install it
(mostly just the downloading took a crazy amount of time). What’s cool is that
when I went back to look at the raw video it was so shaky that Saturn was only
in the viewfinder for about 3 seconds. So, 3 seconds of blurry Saturn stacked
up and throwing away 7 seconds of darkness.
After taking the 10 seconds of video, I imported it and then
played around in RegiStax. Once I got my preferred settings in RegiStax I set
it to process, that took about 40 minutes. The result was it transformed
crumby, shaky low-res video from a 1990s Fuji Finepix 4700 digital camera into
this blast of awesomeness:
Notice how you can see at the bottom right where the sphere of the planet actually casts a shadow on the lower part of the ring as it passes behind the planet! You can also barely make out differences in the rings (darker colors).
RegiStax is a FREE (but long) download available here: http://www.astronomie.be/registax/
You’ll want to install it on a desktop because it is HUGE and powerful program.
Think PhotoShop for 3-dimensions.
Harsher
processing (different settings) with RegiStax of the same 316 frames of video
stacked on top of each other:
Because I was sick of holding my old camera (a 1990s Fuji FinePix 4700 'Silver Brick' that I had since college) up to the
eyepiece I made a cheesy but free afocal astrophotography bracket out of
scraps:
Here is this crazy apparatus mounted on my old tiny telescope. The red ring between the camera and eyepiece is a reel from some white Teflon plumber's tape. It was the perfect size for my old telescope and it's lousy little .9" eyepieces (see below about eyepiece sizes).
The little eyepiece in my hand to the left is what you're probably used to in toy store telescopes and microscopes. It's a .9" Japanese size eyepiece. Tiny, not so great usually. Next to it is some 1.25" format eyepieces. Now we're talking! Better telescopes can accept 2" eyepieces and 1.25" eyepieces with an adapter. Professional quality eyepieces are 1.25" and 2".
Here is my HUGE Zhumell Z8 telescope with a 2" format eyepiece mounted in it (to the right and higher than the Pepsi can). It has a frosted white plastic dust cover on it and yes it IS almost as big as the Pepsi can!! It's actually heavier than an unopened can of soda (in Michigan we call soda "pop").
You didn't believe me when I told you my telescope eyepieces are as big as a pop can did ya?
If you have a Dobsonian-mounted telescope (on a spinning lazy susan style mount) a great user upgrade modification is what I did to my Zhumell Z8 shown here. Mount in on a milkcrate and cut holes on either side of the mount. These mods accomplish a few things: with the addition of a rubber bumper on the bottom of the tube (so it doesn't bang into the mounting as hard) I can now push the telescope tube upright, then bear hug the whole telescope and grab it by the two new huge holes. I push my chest into the tube which mashes it tightly against the mount (and rubber bumper) Yes, I carry my entire telescope out the door in one piece instead of multiple trips! No more carrying the base, then the tube and trying to assemble them in the darkness. The huge pieces I cut out where also pretty heavy, meaning I have less weight to deal with all around, which is nice. The milkcrate just makes it higher so I don't have to lean down and get a backache or migraine while using the scope.
The other piece of advice that really, really helps when using this type of reflector telescope has to do with colimation (lining up the primary and secondary mirrors with eachother, and then lining up the eyepiece--all using a laser). Whenever you make adjustments to the secondary mirror mount screws or the thumbscrews of the primary mirror (but not the locking screws) always try to tighten them to get to where you want things aligned. At first I would loosen one side and tighten another. Once I shifted to always tightening, after a few nights of use and colimation things were so tight that they telescope didn't need to be colimated at all! Things just tended to stay put...and that's after the bear hug and walking down stairs and out a door and down stairs of a stone paver patio!
So, do you have an old Tasco telescope? It's a great telescope with two deadly flaws (that you can fix). For a few dollars you can order a new eyepiece mechanism that will allow you to put 1.25" eyepieces in your telescope! I did this and was blown away by the quality increase when using my good eyepieces in what I thought was a bad telescope. Tasco telescopes are optically fine, they're eyepieces are totally crumby though.
The second deadly flaw is their criminally negligent telescope mounts (tripods). They're just awful and probably were the main reason that 99% of their telescopes end up "used only a few times, asking $10 for it". Find a way to stabilize the mount and you'll love the telescope. This may entail wood and metal working, or haunting charity resale shops (Salvation Army, Disabled American Vets) for a deal on a better mount. For $5 I found a fancy equatorial telescope mount, twenty pounds of counterweights and best part was--it came with my old telescope tube! Yep, the grey telescope I took many cool photos with was only $5 for the scope, great mount with weights and a pile of mediocre eyepieces and other stuff!
I highly recommend the DAV Thrift Store at 8050 N Middlebelt Rd, Westland, MI 48185! The workers are also SUPER NICE!!! They work for charity to help disabled veterans. Probably my favorite place on Earth besides Costco and my own house.
I also like my binoculars big, and mounted on tripods. Above are a pair of great Konus binos I scored cheap off of Amazon brand new.
In later posts I’ll detail my: spectrometers (a few homemade and a store-bought one); infrared experiments and my favorite hobby of all: staring at the sun! Until then just know this: no matter how cheap a telescope or microscope or binoculars you have you can usually stick your camera (even a cellphone camera) up to the eyepiece and take cool pictures afocally.
For the desktop or laptop Stellarium is a great astronomy tool: stars, planets, space junk and satellites visible from Earth are all easy to find using this software. They charge for the mobile app but desktop version is free and way more powerful. I have it on my phone but always seem to use the free app SkEye, which lets me scroll around and even attach my phone to my telescope and it tells me which way to swing the scope to view my target object. There is an align function that's easy: point telescope at a known object, scroll on screen and tap the object. Do that a couple times and your phone and telescope act as one!
Remember, telescopes are just light buckets: the bigger the bucket the more light you grab. The eyepieces do the focusing and magnifying (zooming in). In my big 8" telescope looking at the moon is actually a little too bright and painful. I have to squint. Good thing we don't have super-sensitive cat's eyes.
The moon is so bright that most astronomers don't bother to use their telescopes when it's visible because, much like the sun, it drowns out the stars in the sky. Even the ancients were both awed and annoyed by the moon:
Meow!
If you have a Dobsonian-mounted telescope (on a spinning lazy susan style mount) a great user upgrade modification is what I did to my Zhumell Z8 shown here. Mount in on a milkcrate and cut holes on either side of the mount. These mods accomplish a few things: with the addition of a rubber bumper on the bottom of the tube (so it doesn't bang into the mounting as hard) I can now push the telescope tube upright, then bear hug the whole telescope and grab it by the two new huge holes. I push my chest into the tube which mashes it tightly against the mount (and rubber bumper) Yes, I carry my entire telescope out the door in one piece instead of multiple trips! No more carrying the base, then the tube and trying to assemble them in the darkness. The huge pieces I cut out where also pretty heavy, meaning I have less weight to deal with all around, which is nice. The milkcrate just makes it higher so I don't have to lean down and get a backache or migraine while using the scope.
The other piece of advice that really, really helps when using this type of reflector telescope has to do with colimation (lining up the primary and secondary mirrors with eachother, and then lining up the eyepiece--all using a laser). Whenever you make adjustments to the secondary mirror mount screws or the thumbscrews of the primary mirror (but not the locking screws) always try to tighten them to get to where you want things aligned. At first I would loosen one side and tighten another. Once I shifted to always tightening, after a few nights of use and colimation things were so tight that they telescope didn't need to be colimated at all! Things just tended to stay put...and that's after the bear hug and walking down stairs and out a door and down stairs of a stone paver patio!
So, do you have an old Tasco telescope? It's a great telescope with two deadly flaws (that you can fix). For a few dollars you can order a new eyepiece mechanism that will allow you to put 1.25" eyepieces in your telescope! I did this and was blown away by the quality increase when using my good eyepieces in what I thought was a bad telescope. Tasco telescopes are optically fine, they're eyepieces are totally crumby though.
The second deadly flaw is their criminally negligent telescope mounts (tripods). They're just awful and probably were the main reason that 99% of their telescopes end up "used only a few times, asking $10 for it". Find a way to stabilize the mount and you'll love the telescope. This may entail wood and metal working, or haunting charity resale shops (Salvation Army, Disabled American Vets) for a deal on a better mount. For $5 I found a fancy equatorial telescope mount, twenty pounds of counterweights and best part was--it came with my old telescope tube! Yep, the grey telescope I took many cool photos with was only $5 for the scope, great mount with weights and a pile of mediocre eyepieces and other stuff!
I highly recommend the DAV Thrift Store at 8050 N Middlebelt Rd, Westland, MI 48185! The workers are also SUPER NICE!!! They work for charity to help disabled veterans. Probably my favorite place on Earth besides Costco and my own house.
I also like my binoculars big, and mounted on tripods. Above are a pair of great Konus binos I scored cheap off of Amazon brand new.
In later posts I’ll detail my: spectrometers (a few homemade and a store-bought one); infrared experiments and my favorite hobby of all: staring at the sun! Until then just know this: no matter how cheap a telescope or microscope or binoculars you have you can usually stick your camera (even a cellphone camera) up to the eyepiece and take cool pictures afocally.
For the desktop or laptop Stellarium is a great astronomy tool: stars, planets, space junk and satellites visible from Earth are all easy to find using this software. They charge for the mobile app but desktop version is free and way more powerful. I have it on my phone but always seem to use the free app SkEye, which lets me scroll around and even attach my phone to my telescope and it tells me which way to swing the scope to view my target object. There is an align function that's easy: point telescope at a known object, scroll on screen and tap the object. Do that a couple times and your phone and telescope act as one!
Remember, telescopes are just light buckets: the bigger the bucket the more light you grab. The eyepieces do the focusing and magnifying (zooming in). In my big 8" telescope looking at the moon is actually a little too bright and painful. I have to squint. Good thing we don't have super-sensitive cat's eyes.
The moon is so bright that most astronomers don't bother to use their telescopes when it's visible because, much like the sun, it drowns out the stars in the sky. Even the ancients were both awed and annoyed by the moon:
The stars about the lovely moon fade back and vanish very soon, when round and full her silver face swims into sight and lights all space.
Sappho
Meow!
