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#1 Pharquart

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Posted 11 March 2013 - 06:38 PM

One of the posters in the "handicapped outreach" thread posted something about supplementing a visual telescope with video. Rather than hijack that thread on this tangent, I figured I'd start a dedicated one.

I've often thought of picking up one of the ubiquitous cast-off 60mm refractors or a 4.5" reflector and mounting it in parallel on one of my main scopes, then using a video camera on the smaller scope to show people what the larger scope is looking at.

What suggestions do you have for a video camera? I usually do outreach from a heavily light polluted area, sometimes literally under a street light. So I'd be looking mostly at planets and the moon. I sometimes get out to where a telescope can find M42, M31, or M13. Because I'm in a city, I can either find power for a laptop or small TV or take along my portable power supply.

Any suggestions for a video camera?

Brian

#2 maroubra_boy

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Posted 11 March 2013 - 08:52 PM

Hi Brian,

Very noble of you to start a new thread.

The camera I use is the GSTAR-EX colour camera. Myastroshop does ship internationally. I hook up the camera to a portable DVD player with an AV-in socket. As both the camera & screen are 12v, I just take a suitable 12V battery/power pack.

As this camera is quite small, coupling it to a guide/small scope, or even a camera lens, it can ride piggy back to your main scope.

But note, for the camera to show a reasonable disk size of Jupiter or Saturn it requires a decent amount of focal length, something a 60mm refractor or 114 f4.4 scope just doesn't have.

In the other thread, I mentioned the amount of detail my 80mm f/5 refractor can show in M42 and other DSOs. Don't underestimate how potent the astronomical video cameras are from light polluted areas! M104, the Sombrero Galaxy, was unmistakeable with its dark lane with this 80mm from my location in inner Sydney.

Mallincam cameras I wouldn't hesitate in recommending either. Just superb cameras, & the Mallincam Jnr is only a little more pricey than the GSTAR.

Alex.

#3 buddyjesus

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Posted 12 March 2013 - 12:27 AM

sounds like an excellent plan. maybe the samsung?

http://www.cloudynig...ber/4379862/...

cheap way into video from my investigation, though I never followed up on it.

#4 skyguy88

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Posted 19 March 2013 - 01:28 AM

Hi Brian,

I've been doing video outreach for five years. It works wonderfully. Most of the objects that you will use in the outreach setting will be relatively bright. If that is your only use then camera selection isn't critical. But if you want to do other observing with it, longer exposure is a big help. I started with an early Mallincam and did fairly well with its 12 second limitation. But I eventually added a Hyper plus version and the increased exposure (to 56 sec) made a big difference in view quality and the number of objects that I can observe clearly.

One thing that happens when you use the camera is that because you are working with a group and don't need to help each visitor to find/see your objects, you have time to engage in more extensive discussion. And that increases the engagement. It also makes knowing a lot about your targets more important-a good thing.

Try it..You'll like it.

Bill

#5 Pharquart

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Posted 24 March 2013 - 04:11 PM

I bought a webcam and modded it for astronomy by removing the lens and attaching a 1-1/4" barrel. It worked for the moon, but provided extremely high magnification, something like using a 4mm eyepiece. Jupiter and her moons were visible, but completely washed out as a blaring white blob. I later learned it was because the auto gain feature of the webcam cranked up the gain because of the large dark area of the rest of the sky. This particular camera's software didn't have gain control, and even turning the brightness control down to minimum didn't provide any improvement. (The moon worked, because the whole image area was bright enough so keep the gain set correctly.)

I'm intrigued by the Mallincam and GSTAR-EX, but they're a little out of my price range. I'm looking for something under $100, and something that will provide a little less magnification. The Samsung 435 might be right. Is apparent magnification driven by the chip size? My webcam has a 3mm wide chip. Will cameras with wider chips provide more AFOV and thus lower magnification?

I don't mind risking $10 on a webcam that didn't work. I'm not very hyped about spending $100 or more to buy a camera that won't do what I want: live video astronomy. I'm not trying to stack or image. I just want people to be able to see on a screen something like what they can see in the eyepiece. Will a Samsung 435 do that?

Brian

#6 maroubra_boy

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Posted 08 April 2013 - 04:35 AM

Hi Brian,

Is your 1.25" nose piece threaded for filters? If so, then using one of the cheap 1.25" focal reducers will help reduce the magnification effect. I use one with my C8 otherwise all I'd see is the white's of ET's eyes, so to speak.

I too used a modified webcam as my first video camera. Some Logitech camera drivers do provide a lot of control, including gain. You could easily get a preloved Logitech webcam from a mate for nix, modify it, install the drivers from the net, and get your mits on a focal reducer, all for the cost of the reducer. Astronomics sells one for les than $25:

https://www.astronom...ron-meade-an...

This is the type of reducer I use.

I don't know anything about the Samsung camera, I can't help there.

As you mentioned, the smaller the chip the 'higher' the effective magnification, the only way around this without going to larger chips (& lager $$$) is shorter focal length. Fast, short tube Newtonians are great for this! My newest video rig is my son's 114mm f/4.4 Newt! Absolutely brilliant little scope! I was fortunate to have a mate give me an old set of Meade 8" SCT fork mount that he was about to throw out. It just needed some TLC, a wedge made out of plywood, & the old surveyors tripod I've had for 20 years, & $3 for 3 mounting bolts to couple the mount to the wedge (which cost me $0 as it was made from left over stuff from a previous project). Now I've got a ripper video rig which I'm still to try out with the focal reducer. M42 fits nicely in the screen, and in full colour, and more detail than could be seen naked eye through this scope.

I mention this rig as it shows that it doesn't take a lot to get spectacular results with video. Short tube Newts are very, very cheap, and ones that contain the Barlow shoved down the focuser can be converted to excellent video scopes too, as this CN article describes:

http://www.cloudynig...ts/convert2.pdf

If the pennies are tight, there are some clever ways to have them work wonders.

#7 maroubra_boy

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Posted 08 April 2013 - 06:33 AM

A pic of my 114mm scope video rig with the GSTAR camera attached.

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#8 StarStuff1

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Posted 14 April 2013 - 02:04 PM

The Samsung 435 is a very decent and inexpensive camera. I think it has beeen replaced with a newer model. Visit the "Video and Electronically Assisted Astronomy" forum for many more details and tips. My Sammy cost about $125 shipped. This was after I wasted $400 on two other cams that did not do integration. The Sammy can integrate up to about 8 seconds (IIRC) and is very sensitive. It can do both color and B&W. At one outreach session about this time last year it amazed attendees with a full color image with great detail of M42 and with only a 4 second integration time. Of course this was with a 12-in Schmidt Cass with an inexpensive .5 focal reducer. Even with my 5.1-in f/5 newt it can deliver impressive pics of DSOs at a decently dark location. The first time I used the cam for public outreach was at a kids summer camp. The scope was an AT66. The view of the Moon on the small digital TV just filled the screen. Using the digital zoom on the cam really impressed the kids.

Here is a pic of the cam and TV with the 5.1-in newt.

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#9 Tim Brothers

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Posted 12 September 2013 - 11:23 AM

We're on the hunt for a new video camera as well and while it is for class/research it needs to meet the same requirements as the outreach cameras (needs to integrate and has to be very easy to use). I am mounting ours on the slit entrance to a Lhires III spectrograph to replace our StellaCam3 (junk) and now replacing the replacement supercircuits pc165dnr (more junk). The one thing I did like about the StellaCams is that they have a remote. Do any of these you are recommending have one or easy to use controls?

thanks - Tim

#10 Skylook123

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Posted 12 September 2013 - 11:48 PM

This past year at the Grand Canyon Star Party my granddaughter and I got asked to help with an annual event at the Kaibab Learning Center, a sort of day care plus pre-school education facility for children of Park employees. Our head Ranger used a 90mm spotting scope on the first quarter moon, while I used a Lunt 60mm solar scope with a Mallincam Junior. I fed the signal to a 13.3" monitor that was perfect for the four to seven year olds to see the big basketball of the sun with about five filaments, four bright faculae, five sunspot groups, and filaments around the limb. The camera worked perfectly, with both filaments and surface details available. Perfect use for that setup, and the first time they'd tried video - usually binoculars on a special chair.

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#11 Skylook123

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Posted 12 September 2013 - 11:50 PM

And another view:

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#12 mattflastro

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Posted 15 September 2013 - 02:30 PM

We're on the hunt for a new video camera as well and while it is for class/research it needs to meet the same requirements as the outreach cameras (needs to integrate and has to be very easy to use). I am mounting ours on the slit entrance to a Lhires III spectrograph to replace our StellaCam3 (junk) and now replacing the replacement supercircuits pc165dnr (more junk). The one thing I did like about the StellaCams is that they have a remote. Do any of these you are recommending have one or easy to use controls?

thanks - Tim

Tim,
The Adv Cam MK II and the Peltier cooled cam APU-1 come with remotes that include manual gain, black level and manual integration time adjustments .
If you would like more info, please visit the website (plenty of user captured images) or contact me directly for any questions .

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#13 Tim Brothers

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Posted 18 September 2013 - 03:12 PM

Matt

Do any of these cameras have sensors larger than 1/3" format? I see something about a focal reducer, is that available now? That's what we're using now and it produces a 3x4 arcminute FOV which is just too small. I think we need something at least 1/2" wide. Thanks!

#14 kfiscus

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Posted 18 September 2013 - 11:34 PM

Here is my dirt-cheap and woefully old-school video outreach setup. I just use a $35 Meade black & white digital EP that sends its video signal through a 12' RCA cable into a small garage sale TV. I put the camera into either focuser on my XT10/XT4.5 duo on an EQ platform. The only targets that this insensitive camera can grab are terrestrial targets before dark, the moon, Jupiter, Saturn, Venus.

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#15 core

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Posted 19 September 2013 - 02:18 AM

That's what we're using now and it produces a 3x4 arcminute FOV which is just too small. I think we need something at least 1/2" wide. Thanks!


The alternative is to just use smaller scopes (with correspondingly shorter focal length). For the moon, something in the 500mm or less range allows for much greater areas of the surface to be shown. I've found 80mm-100mm range scopes to be quite capable even for hand-tracked video astronomy.

As for Brian's initial question, outreach video camera for bright objects are quite abundant; imo most everything out there should work fine - you could even slap a live-view DSLR to the scope and view the output video. fwiw use the aforementioned Meade Electronic Eyepiece, or Samsung SDC-435 for outreach events.

#16 Tom and Beth

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Posted 19 September 2013 - 07:03 PM

We're on the hunt for a new video camera as well and while it is for class/research it needs to meet the same requirements as the outreach cameras (needs to integrate and has to be very easy to use). I am mounting ours on the slit entrance to a Lhires III spectrograph to replace our StellaCam3 (junk) and now replacing the replacement supercircuits pc165dnr (more junk). The one thing I did like about the StellaCams is that they have a remote. Do any of these you are recommending have one or easy to use controls?

thanks - Tim


Hello Tim,

The Video Observing group (below) has quite a few members who can suggest cameras for you, but wondering what was it about the StellaCam and Supercircuits that classified them as "junk". Knowing that can lead to better suggestions.

I see the Samsung 435 has been mentioned. Currently branded as SCB-2000 with a more sensitive sensor than the Supercircuits camera, and it integrates up to 512.

I see you are also after an "easy to use" camera, and recently I have been experimenting with Samsung SNB-2000, which has the (I believe) same sensor as the Analog Camera, 512 sense up, but more importantly you can access the control menu and video using a browser. They also have a "HD" version designated SNB-5000 and 7000. A patient buyer can find the SNB-2000 under $150 USD and about double for the SNB-5000. An analog SCB-2000 will set you back about $100.

Bear in mind, this is just a small sample, and those who frequent the aforementioned Video group seem to be well versed in camera specifics.

Edit: An example; this is a screen grab (absolutely no processing) of an image of M27 taken with a SCB-2000 on the back of my C102 (Vixen) refractor with a .5 Focal reducer . Sense up was at 512. These low cost analog cameras can have a remote added by soldering 5 momentary switches and as much wire as you care. Instructions on the Yahoo group.

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#17 David Pavlich

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Posted 30 September 2013 - 12:22 PM

Regardless of what camera you decide on, video outreach is a good thing for all the reasons described. Jack Heurkamp is always a big hit at our outreach events since he's the one that brings the camera.

As an aside, at my first star party (French Camp), I was set up next to Jack and his MallinCam. I had a great time calling out objects that I was looking at (C11 on a CGE) and then look at his monitor to see what it looked like from the camera's point of view. It's something that would work well at an outreach event to demonstrate just how effective the camera really is. Highly recommended.

And, heck, if a grizzled ole' outreach guy like Jim uses one, :grin:, it's gotta' be good!!

David

#18 Skylook123

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Posted 18 October 2013 - 08:34 AM

Yeah, David, I personally am strictly an eyeball at the eyepiece kind of observer, but the impact of video at outreaches has been tremendous for the physically handicapped, visually impaired, and children just too young to get the hang of an eyepiece. I'm upgrading from the Mallincam Junior to the Mallincam Junior PRO to be able to go "deeper" for public events. It shipped today.

Mallincam Junior PRO

#19 skyguy88

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Posted 18 October 2013 - 09:51 PM

Hi David, Jim,

And I am a nearly full time video guy. No debate here, but I would like to point out that with video you can do an outreach program just about any time in the lunar cycle. We did a school program last Wednesday, 2 days before the full moon. Started with the moon and then used M13, M27, M17, and even got a marginal look at NGC 891. The nebulae were a little washed out but still stunning, well detailed and fully colored, Great objects to engage the kids.

Bill






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