Return to the Cloudy Nights Telescope Reviews home pageAstronomics discounts for Cloudy Nights members
· Get a Cloudy Nights T-Shirt · Submit a Review / Article

Click here if you are having trouble logging into the forums

Privacy Policy | Please read our Terms of Service | Signup and Troubleshooting FAQ | Problems? PM a Red or a Green Gu… uh, User

Equipment Discussions >> Electronically Assisted Astronomy

Pages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | >> (show all)
ccs_hello
Postmaster
*****

Reged: 07/03/04

Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: ccs_hello]
      #5286349 - 06/24/12 07:39 AM

Another comment:

Set aside the collness of using the super-high resolution CCD (960H), have you noticed the camera is listed as the 650-700 TVL (TV lines) class?

Typically, the most commonly seen high-resolution (720H or 768H) videocam is listed as 550-600 TVL class.

Essentially, it means that
- At the same image sensor size (e.g., type-1/3"), the super-high reso type's pixel area is 50% smaller (3:2 @ 768H:960H) thus less light gathering.
- However, the horizontal resolution only marginal gain. The culprit is the NTSC CVBS output which choke the bandwidth.

P.S. For the curious,
yes, there are indeed standard reso CCD (512H). (Typically quoted as 330 TVL videocam when used.)
Under the same image sensor format (e.g., type-1/3"), its per-pixel area size is twice as the 960H's.
Who is using this type of classic CCD sensors? A good example is Meade DSI. This is a tradeoff between spatial resolution and more light gathering power.

Clear Skies!

ccs_hello


Post Extras: Print Post   Remind Me!   Notify Moderator  
jbell
sage


Reged: 04/09/10

Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: nytecam]
      #5286381 - 06/24/12 08:13 AM

Quote:

... but I love my Lodestar when it can churn out stuff like this in 1second exposure etc in M13 + Catseye PN [1s]; M92 [1s]; M92 [30s] and M57 [20s]






Quote:

Another comment:...... The culprit is the NTSC CVBS output which choke the bandwidth.....
Clear Skies!

ccs_hello




Yea, the direct usb connect of the lodestar is the bomb... and explains maurices pics. Best astro purchase I've made. When the lxd is cooperating, I can run rings around any other "live" camera in the area.

One other thought... No D/A converter, and no mpeg4 compression on the frame grabber.

my2c.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Raginar
Postmaster
*****

Reged: 10/19/10

Loc: Rapid CIty, SD
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: jbell]
      #5286567 - 06/24/12 11:04 AM

Stupid question, are you guys just using a lodestar autoguider for those pictures?

Chris


Post Extras: Print Post   Remind Me!   Notify Moderator  
mclewis1
Thread Killer
*****

Reged: 02/25/06

Loc: New Brunswick, Canada
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: James Cunningham]
      #5286658 - 06/24/12 12:15 PM

Quote:

I wonder if you use Gstar software whether you could extend the exposure time to 34 seconds? With that chip and a good reducer, you should be able to see almost everything.



Jim, I don't believe the Gstar s/w actually increases the exposure/integration times. It appears to offer a form of stacking and some other image enhancements that improve on the basic images. There are statements about the effects being similar to doubling the integration times of a basic camera.

Increasing exposure/integration time within a camera is a huge trade of with the increase in noise. If you increase integration times you must address noise, if you don't it very quickly overwhelms the images.

One method is to improve the DSP (digital signal processor) and read amp characteristics - this is expensive unless they are part of new hardware/firmware intended for wide spread commercial use (volume pricing). The other method is internal cooling, and so far with video this is strictly for a boutique product (Mallincam, Stellacam) or DIY type of upgrade.

Edited by mclewis1 (06/24/12 12:44 PM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
jbell
sage


Reged: 04/09/10

Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: Raginar]
      #5286815 - 06/24/12 02:02 PM

Quote:

Stupid question, are you guys just using a lodestar autoguider for those pictures?

Chris




Yea.. It's basically a starlight 7c in auto guider form. I believe it's same chip as mallincam but not hampered with NTSC.


Post Extras: Print Post   Remind Me!   Notify Moderator  
mclewis1
Thread Killer
*****

Reged: 02/25/06

Loc: New Brunswick, Canada
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: jbell]
      #5287003 - 06/24/12 03:51 PM

Quote:

Yea.. It's basically a starlight 7c in auto guider form. I believe it's same chip as mallincam but not hampered with NTSC.



Then you'd believe wrong.

Mallincam's use the Sony 418/428 chips, the Starlight Express camera uses a 429 chip. The 418/428 chips have larger pixels.


Post Extras: Print Post   Remind Me!   Notify Moderator  
jbell
sage


Reged: 04/09/10

Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: mclewis1]
      #5287390 - 06/24/12 08:42 PM

that's what I get for posting from my phone and not double checking... yes it's the 429ak.
http://www.sxccd.com/handbooks/Handbook%20for%20the%20Lodestar%20%27Colour%27.pdf

thanks mark.

apology for the off topic


Post Extras: Print Post   Remind Me!   Notify Moderator  
mclewis1
Thread Killer
*****

Reged: 02/25/06

Loc: New Brunswick, Canada
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: jbell]
      #5287510 - 06/24/12 09:59 PM

I don't think it was too off topic. A reminder that a camera's capabilities are much more than simply one sensor vs. another is a good thing.
I find double checking stats becomes more important as time goes by ... (personal experience)


Post Extras: Print Post   Remind Me!   Notify Moderator  
Raginar
Postmaster
*****

Reged: 10/19/10

Loc: Rapid CIty, SD
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: mclewis1]
      #5287550 - 06/24/12 10:18 PM

I never thought to use my lodestar autoguider as a mallincam.

Sorry for OT,


Post Extras: Print Post   Remind Me!   Notify Moderator  
ccs_hello
Postmaster
*****

Reged: 07/03/04

Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: Raginar]
      #5287634 - 06/24/12 11:25 PM

ICX428 and ICX429 are sister CCD sensors. One is primarily designed for NTSC format and the other PAL. The pixel area difference is minimal (8.4 um x 9.8 um vs. 8.6 um x8.3 um) which is 15% more.

The European version of the videocams (and Mallincam) will simply change the sensor used from '428 to '429.

Some astroCCD imagers chose to use these CCDs originally designed for videocam due to (1) large sensor area & large per-pixel area (2) lower price due to mass production and easier to source.

Clear Skies!

ccs_hello


Post Extras: Print Post   Remind Me!   Notify Moderator  
James Cunningham
Post Laureate
*****

Reged: 08/07/10

Loc: Maryland
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: scout72]
      #5287925 - 06/25/12 06:37 AM

I also wonder about the IR filter. Hopefully, it will be almost the same as taking out the IR filter on the Samsung cameras. If you attempt to take out the filter, please let us know how you did it. From the outside, almost all of these cameras look the same. Also, hopefully, it will come with an adapter to fit a 1.25 inch diagonal.

Post Extras: Print Post   Remind Me!   Notify Moderator  
WillCarney
Pooh-Bah
*****

Reged: 10/08/09

Loc: Bloomington, ILL
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: Raginar]
      #5288123 - 06/25/12 09:52 AM

Quote:

Stupid question, are you guys just using a lodestar autoguider for those pictures?

Chris




I've used one for a number of different picture events.
I have used wide angle lenses 6-15mm for shooting meteors and satellites. As well as using it in the telescope as a camera. On several occasions I used a QSI as a guider and the Loadstar as the camera.

William


Post Extras: Print Post   Remind Me!   Notify Moderator  
mclewis1
Thread Killer
*****

Reged: 02/25/06

Loc: New Brunswick, Canada
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: James Cunningham]
      #5288552 - 06/25/12 02:52 PM

Quote:

I also wonder about the IR filter. Hopefully, it will be almost the same as taking out the IR filter on the Samsung cameras. If you attempt to take out the filter, please let us know how you did it. From the outside, almost all of these cameras look the same. Also, hopefully, it will come with an adapter to fit a 1.25 inch diagonal.



Jim,

It will not come with an adapter. It likely won't come with anything extra. It may not even come with a manual of any sort. It's a C mount box camera, designed for low light security use. The usual customers are security systems integrators who have a fair amount of experience with similar cameras (yeah I know, if you met any of these folks I may be giving them more credit here).

Because it's a day/night or low light type of camera is has settings to take advantage of these low light conditions which makes the camera of interest to us in the video astronomy side of things.

Just like a Samsung security cameras you'll need to figure out the removal of the IR filter (lets pray that with this camera that it's as easy to do as with the Samsung and not something that's well glued in place), source a C mount to 1.25" nose piece (the adapter you mentioned) - a cheaper model made from Delrin is appropriate here but you should also be able to use the one that came with your Mallincam if you choose to, and a suitable +12v power source. Note that the power connections are small screw on type so you'll need to have a cable with bare wire ends and you'll need to ensure that you always get the polarity correct. Put the wires in the wrong way and you'll likely fry the camera.

The video connection is composite only via a BNC connector ... again some of the stuff that came with your Mallincam may help out here.

Then there's the menu system which is likely to be quite different than that on the Samsungs. Nobody will know what settings are appropriate for planets or DSOs (although some educated guesses will likely get somewhat close).

Using this camera for astronomy purposes will be a real DIY project. Not a tough project for those folks with experience with the Samsungs or similar but it's definitely not a commercial plug n play type of setup. There won't be any hand holding available until a few folks have time to really work with the camera.


Post Extras: Print Post   Remind Me!   Notify Moderator  
jambi99
sage


Reged: 08/14/10

Loc: Québec, Canada
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: mclewis1]
      #5289253 - 06/25/12 10:03 PM

I just ordered one too.The thing is that i sold my scb-4000 a month ago to finance my Orion deep sky imager II hehe. However, i was planning to get a scb-2000 for quick observation and for planetary. Therefore for 75 $ (50 $ cheaper than the scb-2000) and some better specs(on paper), i think its good bet.

Post Extras: Print Post   Remind Me!   Notify Moderator  
jambi99
sage


Reged: 08/14/10

Loc: Québec, Canada
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: ccs_hello]
      #5289275 - 06/25/12 10:21 PM

Do you think the 50% smaller pixel size can truly be translated to 50% loss of light gathering? This, compared to the the original exview sensor? People seem to report that the scb-2000 is actually pretty close in term of sensitivity compared to the scb-4000. Despite pixel size 40% smaller and the fact the the camera has a super had II sensor. This is why i sold my scb-4000. I don't think the difference is that much. Correct me if I'm wrong, but it seems that integration time and focal ratio seem to have more effect on the camera sensitivity.

Post Extras: Print Post   Remind Me!   Notify Moderator  
ccs_hello
Postmaster
*****

Reged: 07/03/04

Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 new [Re: jambi99]
      #5289355 - 06/25/12 11:55 PM

jambi99,

It is a long story to tell. But a general rule of thumb is:
under the same generation of technology improvements, the per-pixel area "photon to electron" conversion factor tends to scale linearly, except toward the smaller pixel size, the line starts to go flat and even curve up until the pixel size is far too small to be worthy for that generation of technology.

Of course, long integration time and fast f-ratio is forcing more star-light to fall into the same pixel "photon bucket" thus more signal ("S" part of S/N) to help the image quality.

P.S. you might have noticed that I have been careful not to use the terms: sensitivity (fuzzy, misunderstood, misinterpreted, or even "cooked" term) and QE (multiple definitions and some are misleading).
Thus my post is dry and imprecise. Sorry about that.

Clear Skies!

ccs_hello


Post Extras: Print Post   Remind Me!   Notify Moderator  
ccs_hello
Postmaster
*****

Reged: 07/03/04

Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 [Re: ccs_hello]
      #5289376 - 06/26/12 12:12 AM

To complement my previous post, let me express my personal opinion/guessing...

If that videocam mfg makes two models of the 1024x videocams, if everything are made the same except
one is using an ExviewHAD II type-1/3" high-resolution CCD, and
the other is using an ExviewHAD II type-1/3" super-high resolution (960H) CCD

I'll pick the former, if low-light performance is the main decision factor. Note that spatial resolution for that 960H version won't be that high anyway.

Clear Skies!

ccs_hello


Post Extras: Print Post   Remind Me!   Notify Moderator  
jambi99
sage


Reged: 08/14/10

Loc: Québec, Canada
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 [Re: ccs_hello]
      #5289401 - 06/26/12 12:54 AM

I agree too and it think that any improvement is always good. However, my point is that the pixel size and the sensor type seems to be quit negligible with very fast f-ratio. See, we are using these cameras in a particular way. The fact that we are using these camera with really fast focal ratio is not, in fact, what they are designed for. Let me us the analogy of the water bucket. Lets say you put these buckets(bigger and smaller) under a rain fall(normal use of the CCD). Then, the bucket size will matter. However, if you put the same buckets under the niagara fall(fast f-ration), the bucket size doesn't matter anylonger. Sorry, the analogy might be a little a inaccurate, but it give you an idea of what i mean.

Post Extras: Print Post   Remind Me!   Notify Moderator  
core
Pooh-Bah
*****

Reged: 02/23/08

Loc: Mostly in Norman, OK
Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 [Re: jambi99]
      #5289416 - 06/26/12 01:06 AM

Quote:

See, we are using these cameras in a particular way. The fact that we are using these camera with really fast focal ratio is not, in fact, what they are designed for.




The way I'm reading it ... the original intent of these cameras are for cctv applications - most all C/CS mount lens I've seen have very larger apertures - eg, I have a 8mm f/1.6, 25mm f/1.4, 12.5mm f/1.3


Post Extras: Print Post   Remind Me!   Notify Moderator  
ccs_hello
Postmaster
*****

Reged: 07/03/04

Re: 17 sec (x1024) Camera Sony 960h Exview HAD CCD2 [Re: core]
      #5289666 - 06/26/12 08:11 AM

Peter,

Shorter focal length lenses are easier/cheaper to make. The Entrance pupil (or Objective lens diameter) in the above examples are just 5mm, 17.85mm, and 9.6mm respectively. A long focal length with fast f-ratio, even if the lens' output image circle size does not need to be large (just large enough to cover videocam's tiny type-1/2" sensor area), the price will be high and Chromatic Aberration will require premium optics.


jambi99,

What you are describing is known as the common imaging triads:

(a) make the exposure time longer, thus more photons can be collected
(b) make the optical system more efficient to "funnel" the incoming photon flux to the "photon detection apparatus". E.g., fast optics, better lens coating (if refractors, if typical camera lenses), better mirror coating (if reflectors).
(c) make the "photon detection apparatus" (e.g., an image sensor) more efficient in converting/processing/displaying an image.

For (a), requires better tracking, polar alignment, good light pollution control, and better seeing.
For (b), requires more investment on premium optics
For (c), requires more technology advancements (opto-electronics, electronics, image science & processing, etc.) and sometimes serious money.

In another word, under photon starvation shooting condition (like us the astro people), that Niagara River is just a drying stream and would require a lot of help, (a)+(b)+(c) incurs a lot of trade-offs.


Luckily, in this VEAA branch, at the current time, I'd say it's a golden age under these constraints:
- inexpensive long exposure videocams (re-purposed from mass-market security-industry day-night CCTV cameras) are readily available
- its low spatial resolution, (arguably some may add the word barely) good enough (NTSC video) quality, and tiny sensor area put less burdens on mount's tracking and premium optics

From this baseline, there are multiple directions to branch out. Some will say the ROI (return of investment) will not be that great any more . Of course everyone is entitled to have his/her own opinions on those factors.

Clear Skies!

ccs_hello


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | >> (show all)


Extra information
6 registered and 10 anonymous users are browsing this forum.

Moderator:  David Pavlich, JayinUT 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 37408

Jump to

CN Forums Home


Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics