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First real test with Watec


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After years of struggling to see faint objects I finally decided to have a go at video astronomy and bought a Watec a couple of weeks ago.

I've tried it out a few times, but tonight was the first time I put it on the tracking mount. It really is pretty impressive. At the moment I'm using it with a small (4.5") f4 Newtonian. Even at quite short integrations (1-5 seconds) objects that can't be seen from my site in the scope alone show up easily (e.g. M110 & M76). Tonight the pick of the bunch was NGC891. I've never managed to see this even in my 12" scope, but with the Watec in the 4.5" it was easily visible with a very distinct dust lane at 10-20 seconds integration. The other nice thing about it is that stars are nice and tight across the whole field of view, whereas most eyepieces show a fair amount of coma in the outer 30% of the fov in this scope.

I'm planning to have a go with the 12" scope, if only I can get it balanced on the mount! I'm looking forward to tracking down that long list of faint objects that I've failed to see visually before :)

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Andrew, I live in the east end of London and as you can imagine the light pollution is pretty bad even though I back onto a wood. I tried to see M51 but could just make out the dense core of the galaxy but nothing else. I bought a Watec 120+ from Modern astronomy and plugged it into my JVC 17" monitor and the spiral arms became visible. Many objects have now been seen from my location which was impossible to see under any circumstances so it was money well worth spending. May I ask what monitor you are using? And when you get it plugged into the 12” it will blow your mind and will revolutionise your viewing. Steve

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I have some initial AVIs of external galaxies, taken with an (F12!) MAK127... Maybe I can upload them. But I sense these were not the ideal examples! I can e.g. clearly see the (Mag-15?) central star of M57. I could also see "dark lanes" of galaxies etc., in real time. Open / Globular clusters are almost "trivial"! Basic stacked images reveal a lot more. Still working on my TS/GSO F4/8" Newt, which should give me far better Signal/Noise ratio? :)

Edited by Macavity
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I hope to get the 12" on the mount soon. If it proves too unwieldy I may get an 8" Newtonian instead.

I'm using a laptop at the moment. I was thinking of looking for an old B&W portable TV (I heard these were good) although the Watec instructions suggest they can't be plugged straight into a TV (I'm not sure if I've misunderstood this).

I've also been thinking about using it with the AstroVideo software (in order to stack images on the fly). The Astrovideo site suggests this software only works with Windows XP or earlier, or with 32 bit OS, but in fact it will work with Windows 7 64 bit if you change settings by right clicking and troubleshooting compatibility.

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I was thinking of looking for an old B&W portable TV (I heard these were good) although the Watec instructions suggest they can't be plugged straight into a TV (I'm not sure if I've misunderstood this).
The good old Cathode Ray Tube TV (or even a portable LCD TV) would be good. But it would need some kind of "direct" (video monitor) input. Otherwise one gets lost in "modulator" interfaces etc. Usually some kind of direct input via RCA Connector is best... :)

Still looking for some (low voltage, budget) small 4:3(?) monitor though... :(

Edited by Macavity
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I heard the cathode ray tube gives the best (brightest) results, but my grasp of electronics is not great so I'm not sure what's needed in terms of cables. Ultimately I hope to compare that vs progressive stacking of images on the laptop while viewing using AstroVideo. At the moment I'm still getting to grips with polar alignment and using a driven mount!

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After years of struggling to see faint objects I finally decided to have a go at video astronomy and bought a Watec a couple of weeks ago.

I've tried it out a few times, but tonight was the first time I put it on the tracking mount. It really is pretty impressive. At the moment I'm using it with a small (4.5") f4 Newtonian. Even at quite short integrations (1-5 seconds) objects that can't be seen from my site in the scope alone show up easily (e.g. M110 & M76). Tonight the pick of the bunch was NGC891. I've never managed to see this even in my 12" scope, but with the Watec in the 4.5" it was easily visible with a very distinct dust lane at 10-20 seconds integration. The other nice thing about it is that stars are nice and tight across the whole field of view, whereas most eyepieces show a fair amount of coma in the outer 30% of the fov in this scope.

I'm planning to have a go with the 12" scope, if only I can get it balanced on the mount! I'm looking forward to tracking down that long list of faint objects that I've failed to see visually before :D

Andrew ,

wow , that sounds impressive for a 4" Newt...actually I have been thinking of a 6"...the eights and bigger really start getting heavy which starts causing tracking issues unless you have a very solid mount..enjoy the camera and bring on some images.

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Had another go with the watec a couple of nights ago. Saw several more objects using the 4.5" Newt + Watec that I can't see with a 12" Newt alone (several faint galaxies, bubble nebula, spiral arms in M81 - in the 12" I can only see the core).

Tried to get the 12" on the NEQ6 but gave up because it's just too unwieldy. Could probably do it with some sort of frame to hold the scope while I lower it on! Either that or it's a two person job. Not really a viable option for everyday use. Think I may get an 8" Newt, which I should be able to put on the mount easily enough.

Also started playing around with different bits of software (GSTAR, Deepsky stacker, AstroVideo). Will post some images when I sort out the best setup (assuming we get some clear skies at some point).

Edited by Andrew
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The Watecs are fantastic, used one for about 18 months now, some of my sketches using the thing are posted on the sketching part of the forum.

I use an old 17 inch tft monitor i bought of ebay for nothing and I also bought a video converter box also of ebay to convert the signal so it can be shown on the monitor but i also use my old laptop with a video grabber usb dongle to display the image and best of you can simply record what you see as an AVI but I would use an older monitor i.e. non widescreen or the image will be stretched out, not good if you are sketching!

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would this camera be any good to use with a scope?

Watec WAT-202D

  • Multi AE modes
  • Various white balance settings
  • White balance control(6 types)
  • Shutter speed control(8 steps)
  • Flickerless mode
  • AGC
  • Back light compensation
  • Gamma correction
  • Effective pixels: 380k(N), 440k(P)
  • Resolution: 450TVL, 470TVL(Y/C)
  • Minimum illumination: 1.0 lx. F1.2
  • Gain control: AGC ON(HI:8-36dB, LO:8-24dB), OFF(12dB)
  • Back light compensation: ON/OFF
  • S/N ratio: 50dB
  • Shutter speed: EI(1/60(N) or 1/50(P)-1/100,000), FL, OFF, 1/250, 1/500, 1/1000, 1/2000, 1/4000
  • White balance: ATW, PWB, MWB, 3200K, 4200K, 5100K, 6300K
  • Gamma: 0.45/1.0
  • Weight: 160g
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Hi

The key parameter is "minimum illumination" and 1.0 lux is no where near low enough.

In addition this camera does not have any in camera integration options - the Samsung SCB000 would be a much better option - this has a minimum illumination value of 0.05 lux and can go down to 0.0001 lux with in camera integration (512 fields or about 10 seconds).

And it's cheaper!!!

Hope this helps

Paul

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Hi

Some cameras have an integration mode - basically allows longer exposures that the 1/25 of a second normally found in video cameras.

The are normally indicted by x2, x4 ... x512 - denoting the number of frames that are integrated. You can think of this as in camera stacking of frames but without the alignment. I reality it's more like setting the exposure to be a multiple of the frame rate (which is fixed for a video camera at 1/25 or 1/30 of a second for PAL or NTSC cameras).

I believ that some of the Watec and Minitron cameras offer this as well as some of the Samsung models.

In the end what you are looking for is a minimum Lux value of less than 0.001 if you want to stand a chance of imaging dimmer DSOs - for planets and the moon this is not necessary.

Hope this helps

Paul

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thankyou i am trying to get a live view (not to photo) just to look on a screen of dso rather than planets but watec(which i have heard are great) just dont seem to be avalible here anywhere.

so i kjeep looking but is the f/ and lux that are the important things to look for? do i need to look at anything else?

how about this 1?

Specification

  • Image Sensor 1/4" CCD
  • Video Quality 400 TV Lines
  • Number of Effective Pixels NTSC: 510 x 492 / PAL: 500 x 582
  • Minimum Illumination 0 Lux / F1.2<------------------------------------------this better?

  • Day/Night Mode Color during day / switches to B&W at night
  • White Balance Automatic
  • Signal / Noise Ratio > 48dB
  • Electronic Shutter 1/60 - 1/100,000 NTSC or 1/50 - 1/100,000 PAL
  • Gain Control Automatic
  • Backlight Compensation Yes
  • Wide Dynamic Range No
  • Lens 6mm
  • Viewing Angle 33 degrees
  • Night Vision
  • Number of infrared LEDs 18
  • Infra-Red Wavelength 850nm
  • Night Vision Distance Up to 65ft / 20m
  • Infra-Red LED Life 10,000 hours
  • Operating Power DC 12V
  • Operating Temperature 0 degrees C ~ 50 degrees C / -32 degrees F ~ 122 degrees F
  • Body Construction Aluminum
  • Dimensions - Camera 5.9" x 2.5" x 2.1" / 61mm x 61mm x 125mm
  • Weight - Camera 0.7 lbs / 321 g
  • Weight - Camera & Stand 1.0 lbs / 457 g
  • Cable Length 32ft / 10m
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Minimum Illumination 0 Lux / F1.2<------------------------------------------this better?
A confusing specification [ZERO!] if ever? The "minimum illumination" of the Watec 120N+ is quoted as 0.00002 Lux F1.4. (I counted Four noughts!) That gives me a vague handle on things, relaive to older CMOS "lunar and planetary" imagers ("A few lux"?), the Celestron NexImage ("<0.1 lux", if I remember rightly?). "Not sure / convinced" is my initial reaction. :icon_salut: Edited by Macavity
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ok so you thinkj the specs are wrong (may be to make them look good?)

so does any1 have ideas on on a ccd that is around £100 or less that gives good live view on dso's?

i cannot find watec's so need another make that is more avaliable.

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