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Why use video over CCD cameras for visual??

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#1 Jay B

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Posted 10 February 2013 - 10:56 PM

Hi
I am interested in video astronomy. I just go a focal reducer and was playing around with an imaging source dbk camera I use for planetary imaging. I am pleased with my initial results. I was able to reduce exposures to 10 seconds without to much noise. The orion nebula looked nice! Way more than visual!!!. The same with the crab nebula. My question is: why not just use something like my imaging source camera or a dedicated CCD imaging camera with 6 second to 40 seconds or so exposure rather than a video camera for viewing? Video cameras require extra steps for frame grabbing etc. Plus I would guess that some of the CCD camera have more sensitive/better chips-especially for the price. Am I missing something here?
Thanks for input and opinions.

Jay

#2 mclewis1

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Posted 10 February 2013 - 11:19 PM

Jay,

The best quality images from a video camera are usually seen on directly connected video monitors but some frame grabber/PC combinations can rival these images. The frame grabber does introduce an extra step and it can impose some visual artifacts but there are many other benefits on the video side.

The sensors used in many video cameras actually tend to be more sensitive than what's used for solar system imaging (to start with many use CYMG vs. RGB masks). Many of the video cameras are built for longer exposure capabilities with a lot of additional noise reduction capabilities (like cooling).

If you look at the security oriented video cameras they probably compare quite closely with many of the solar system cameras (exposure wise, noise wise, etc.), but if you look at the purpose built astro video cameras (Mallincams, StellaCams, etc.) then you'll find quite a few differences.

You mentioned being able to work at 10 second exposures without too much noise. With many purpose built video cameras you're just starting out at 10 seconds, they are designed to minimize noise when exposing for many 10s of seconds to many minutes.

You can certainly do a lot with the latest solar system oriented cameras (much better than visual), they have certainly improved a lot in the past few years, but you can usually do even more with many of the purpose built video cameras (albeit at a higher price).

#3 rmollise

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Posted 11 February 2013 - 09:31 AM

Hi
I am interested in video astronomy. I just go a focal reducer and was playing around with an imaging source dbk camera I use for planetary imaging.


Well, other types of cameras can work somewhat, as you've discovered, but the Mallincams are designed for this. Unlike the planetary camera, they are cooled to reduce noise, and can go way past 10-seconds. They are also much more sensitive than CCD cameras, with small chips with large pixels. ;)

#4 jambi99

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Posted 11 February 2013 - 10:23 AM

Well, a ccd camera having the same ccd(icx429) , functioning at the same f-ratio would have the same sensitivy. There is no magic here. You can't create photon from nothing. Well, except if you have a emccd.Personnaly i took the ccd approach because its way way more cheaper and morebversatile.

#5 rmollise

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Posted 11 February 2013 - 05:08 PM

Well, a ccd camera having the same ccd(icx429) , functioning at the same f-ratio would have the same sensitivy. There is no magic here. You can't create photon from nothing. Well, except if you have a emccd.Personnaly i took the ccd approach because its way way more cheaper and morebversatile.


That's true....EXCEPT (there's always that catch)...there are not many CCD cameras with this chip, and none with video output, and none with Rock's mild cooler. Other than that...though...yeah... ;)

More versatile? Maybe, maybe not. As sensitive? Nope.

#6 nytecam

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Posted 11 February 2013 - 05:09 PM

Well, a ccd camera having the same ccd(icx429) , functioning at the same f-ratio would have the same sensitivy. There is no magic here. You can't create photon from nothing. Well, except if you have a emccd.Personnaly i took the ccd approach because its way way more cheaper and morebversatile.

Well said - it's an ever-perpetuated myth that video is more sensitive than CCD cams using the same, often Sony, sensor - it ain't so :lol: CCD cams only need a USB laptop connection for power and control and the laptop is all I carry to the scope - the cam hasn't moved for months and rarely needs a focus tweak but I do have the luxury of a dome as avatar. Check out my gallery :grin:

#7 Jay B

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Posted 11 February 2013 - 09:56 PM

Thanks for the infor. I understand that my imaging source camera, a planetary imaging camera, will not compare to a mallicam extreme. However I will reframe my question:
Why would a mallicam be any better than a comparable priced ( or lesser priced) CCD cooled camera made for deep sky imaging? For example, orion starshoot pro V20 at $1200 ( a little cheaper) which can go from .002 seconds over 9 hours.

http://www.telescope...-CCD-Imaging... camera


It seem that some of the pictures I see with the mallicam are already "pushing the limit" of real time. In other words, why would a mallicam extreme capture at say 30 seconds be in better than a dedicated CCD camera at 30 second with the same scope? Has anyoe done any comparisons using the same telescope etc.

#8 ccs_hello

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Posted 11 February 2013 - 10:23 PM

I think Orion G3 most resembles some video imagers referred here.
See this CN thread.
Unfortunately, its software side isn't so good so no further info on its near-realtime mode.

Clear Skies!

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#9 Dwight J

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Posted 11 February 2013 - 10:26 PM

Part of the reason Jay is that the Mallincam Extreme is not a 6.1 megapixel chip. It is much smaller and boasts larger pixels, not necessarily desirable for a CCD imager. The large pixels are more sensitive so a 30 second shootout would be no contest. CCD cameras need to have the image processed to show color. I just sold both of my CCD cameras as they were just not used once I bought a Mallincam VSS. If CCD cameras worked so well for "near real time" viewing no one would have bought a Mallincam, Samsung, etc. You don't need a ton of equipment either. When I am out in a dark sky area I control the mount using SkySafari and plug the camera (which runs on 12V) into a battery powered TV. The iPod controls the scope and plays the tunes as well. If you want to do imaging get a CCD camera designed for that purpose. For near real time a camera designed for that reason will perform better. I can get M27 in 7 seconds in color in the Mallincam whereas it barely shows in a noisy 20 sec monochrome CCD image. I am sure, given the recent flavoring of this forum, that someone who thinks they are smarter than I am will say it ain't so. I am relying on experience with both and once I saw jaw-dropping images from the Mallincam, I had to have one. Just call me a fan-boy.

#10 ccs_hello

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Posted 11 February 2013 - 10:35 PM

... For example, orion starshoot pro V20 at $1200 ( a little cheaper) which can go from .002 seconds over 9 hours...


Have to say this is a funny example or coincidence :). That imager is almost identical w/ MC Universe except that
1) the latter claimed to have a hyper circuit
2) the latter has a custom software to address near-realtime viewing mode
3) the latter claimed the image sensor used is special <-- picture on that sensor invited

I believe that topic also has been discussed. :)

Clear Skies!

ccs_hello

#11 jambi99

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Posted 11 February 2013 - 10:49 PM

Following camera would be perfect:

Orion StartShoot II (cooled)
Meade DSI II
StarLigth Xpress LodeStar-C
BrightStar Mammut (cooled)

What they have in common ? Yes, exview color sensor...

The first two one can be found used and under 300$. I just
got a StarShoot II for 250 $ and the camera is only 3 or 4 years old. Personally and compared to the price of the mallincam, its a steal.

Don't get me wrong, i think the mallincam work very well. But for the price difference i just don't see the point. Also, i don't understand people that are so allergic to use a laptops on the field. You can get a decent small netbook with 9" screen for200$. Its about the same price has a good quality lcd screen and its about the same size. Plus,you can use the netbook for other stuff.

:confused:

#12 Jay B

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Posted 11 February 2013 - 10:50 PM

Maurice
I checked out your gallery with the lodestar. Very impressive. It looks like you are doing what I was wondering about. Dwight and other folks thanks for your kind input. Good feedback on this thread so far. I also appreciate the last post above which has specific camera suggestions-awesome.
Jay

#13 mpgxsvcd

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Posted 11 February 2013 - 10:56 PM

Also, i don't understand people that are so allergic to use a laptops on the field. You can get a decent small netbook with 9" screen for200$. Its about the same price has a good quality lcd screen and its about the same size. Plus,you can use the netbook for other stuff.

:confused:


Because there are a lot of visual observers out there that will not appreciate the laptop and the light it produces as much as you do.

#14 ccs_hello

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Posted 11 February 2013 - 11:06 PM

...
Because there are a lot of visual observers out there that will not appreciate the laptop and the light it produces as much as you do.

Hmmm... that's strange. Isn't that video monitor also produces light pollution as well :) :) ??

P.S. mount-side laptop can be operated with lid closed while being remote viewed using VNC.

Clear Skies!

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#15 jambi99

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Posted 11 February 2013 - 11:12 PM

Just use a Night (red) windows themes and a black desktop background. Red light is soft on the eyes.You can also set the brightness to a lower level.Its just a 9" screen.Also, you can use these:

http://www.youtube.c...h?v=_MsRA1Wq0IY

#16 mpgxsvcd

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Posted 11 February 2013 - 11:18 PM

Just use a Night (red) windows themes and a black desktop background. Red light is soft on the eyes.You can also set the brightness to a lower level.Its just a 9" screen.Also, you can use these:

http://www.youtube.c...h?v=_MsRA1Wq0IY


Wow I like the privacy filter. I need to get that. With a lapdome that would be perfect. Thanks for the link. Where can you buy it?

#17 mpgxsvcd

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Posted 11 February 2013 - 11:21 PM

...
Because there are a lot of visual observers out there that will not appreciate the laptop and the light it produces as much as you do.

Hmmm... that's strange. Isn't that video monitor also produces light pollution as well :) :) ??

P.S. mount-side laptop can be operated with lid closed while being remote viewed using VNC.

Clear Skies!

ccs_hello


Easier said than done if you don't have an internet connection where you are observing. Also some observers don't like ANY extra light pollution at all.

#18 jambi99

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Posted 11 February 2013 - 11:30 PM

They are widely available.You can get them from staples:
http://www.staples.c...95_2-CA_1_20001

Pretty sure you could get them for cheaper somewhere else.

However and to be honest, i didn't get one my self yet. So, i can't confirm it will work well on the field. But base on the video, i think its worth giving it a try..

#19 mattflastro

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Posted 11 February 2013 - 11:46 PM

Hi
I am interested in video astronomy. I just go a focal reducer and was playing around with an imaging source dbk camera I use for planetary imaging. I am pleased with my initial results. I was able to reduce exposures to 10 seconds without to much noise. The orion nebula looked nice! Way more than visual!!!. The same with the crab nebula. My question is: why not just use something like my imaging source camera or a dedicated CCD imaging camera with 6 second to 40 seconds or so exposure rather than a video camera for viewing? Video cameras require extra steps for frame grabbing etc. Plus I would guess that some of the CCD camera have more sensitive/better chips-especially for the price. Am I missing something here?
Thanks for input and opinions.

Jay

What exact Imaging Source camera model are you using ?

#20 mattflastro

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Posted 12 February 2013 - 12:01 AM

... For example, orion starshoot pro V20 at $1200 ( a little cheaper) which can go from .002 seconds over 9 hours...


Have to say this is a funny example or coincidence :). That imager is almost identical w/ MC Universe except that
1) the latter claimed to have a hyper circuit
2) the latter has a custom software to address near-realtime viewing mode
3) the latter claimed the image sensor used is special <-- picture on that sensor invited

I believe that topic also has been discussed. :)

Clear Skies!

ccs_hello

Simple and short question, what is in reality behind the Hyper circuit _name_ ? IT's just a name, but whatever circuitry bears that name could be groundbreaking or could be trivial. Until we find out, it's just another marketing name for an analog front end .

#21 ccs_hello

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Posted 12 February 2013 - 12:14 AM

Video monitor also shines lights, not just computer monitor :).

WiFi can be setup without Internet involved.

#22 mpgxsvcd

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Posted 12 February 2013 - 12:42 AM

Video monitor also shines lights, not just computer monitor :).

WiFi can be setup without Internet involved.


Right and that is why nothing is allowed in some places.

Not sure how wifi without internet helps you get rid of the monitor for video viewing? Or am I missing something?

#23 ccs_hello

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Posted 12 February 2013 - 08:39 AM

re: Not sure how wifi without internet helps you get rid of the monitor for video viewing?

Remoting the mount-side device is the key (thru wireless, e.g., WiFi.)

#24 rmollise

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Posted 12 February 2013 - 09:37 AM

If you want to find out, you might try actually using a Mallincam. :lol:

#25 mpgxsvcd

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Posted 12 February 2013 - 10:31 AM

If you want to find out, you might try actually using a Mallincam. :lol:


I did. Not sure how to use it with wifi and without internet though? Seems pointless to hook it up to a computer with wires and then broadcast it to another computer that is not on the net.






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