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Equipment Discussions >> Electronically Assisted Astronomy

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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Samsung SCB-4000/2000 vs Canon T2i sensitivity
      #5596424 - 12/30/12 03:51 PM

Will Samsung SCB-4000 or 2000 show more details on less bright DSOs (i.e. galaxies) than a Dslr like Canon T2i at ISO 1600 after a 4s or 10 seconds exposure?

Currently I'm using a Canon T2i with MagicLantern and C11 at F6 for video astronomy which enables 4s exposures in Liveview, similar to a Mallincam. It's ok for bright DSOs but not enough for live viewing of galaxies.
I should tell you that the T2i is getting quite hot during video astronomy.
I don't afford a Mallincam but I would like to know if the SCB-4000/2000 is considerably better/sensitive than a T2i for video astronomy.

Has anyone compared those CCTVs with a DSLR?


Happy New Year folks!


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StarmanDan
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Reged: 08/27/07

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5596662 - 12/30/12 06:11 PM

The CCTV will be more sensitive. I've seen the companion galaxies to the Deer Lick with my Sammy 2K & 8" SCT at f/6.3 and 512x exposure.

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ccs_hello
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Reged: 07/03/04

Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5597105 - 12/30/12 11:07 PM

I am unaware of that T2i can do "video", 4 second exposure, and "liveview" at the same time.

Can you elaborate?

BTW, DLSRs are designed mainly focused on high S/N while many of the devices mentioned in this specific subforum trading off that for "faster image acquisition time".

Clear Skies!

ccs_hello


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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: ccs_hello]
      #5597350 - 12/31/12 03:26 AM

@ccs_hello: Yes, I do video astronomy with my Canon T2i + MagicLantern with frame integration time up to 4 seconds. For this in MagicLantern you need to set up the function FPSOverride to 0.15 and you'll obtain a Mallincam like image in 4s in LiveView. You'll see the image "growing" on the LiveView display.

As a side note, after a test on M42 I obtained the same image quality after a 4s photo with T2i or 4s in FPSOverride in LiveView on T2i. The difference was I could film M42, not picture it, with FPSOverride.

Problem is I don't know which device is more light sensitive after 4s, the T2i (with a bigger sensor) or Mallincam!

Keeping the idea, will the Mallincam show more on a galaxy after 50s integration time than 50s picture done with T2i, considering both devices accumulate photons during the same period of time?

Is the final result the same but only the method different?

Have you made such a comparison?


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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: StarmanDan]
      #5597351 - 12/31/12 03:34 AM

@StarmanDan: How much more sensitive is the Samsung vs dslr in your experience? Can you exemplify to help me better understand the difference?

What dslr have you used for comparison?

Considering the Sammy 2k is limited to 10s integration time, will a DSLR show much more after, let's say, a 60s exposure?


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mclewis1
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Reged: 02/25/06

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5597643 - 12/31/12 10:08 AM

The CMOS sensor in the DSLRs is not quite as senstive as the larger pixel/cell Sony CCD sensor used in the video cameras. But if you are comparing a camera's overall sensitivity you also need to look at the gain and noise reduction capabilities.

A commercial security video camera has similar gain characteristics to most DSLRs (which have come a long way in the past few years). A Mallincam is built to go beyond this by adding high quality amplifiers and internal cooling to further reduce noise and allow longer exposures.

Controlling internal heat is a big deal for continuously read sensors (during "live" viewing).

Security cameras tend to give you the best bang for your buck and lowest entry price points. Cameras with larger CMOS sensors (DSLRs/mirrorless) offer more resolution and larger fovs (and general photography capabilities) at the expense of some sensitivity (at both short and longer exposures). Purpose built video cameras (Stellacam/Mallincam) offer increased sensitivity over either of these other cameras.

It's very difficult to compare overall sensitivity of various cameras from just the manufacturers specifications (they all seem to use different testing methodologies and rarely at the extremely low light/contrast levels required for astronomy use). Because of this and huge number of variables (scope size and condition, f ratios, sky conditions, etc.) the only really effective method of comparison is side by side viewing and given the cost of the higher end cameras this isn't very popular.


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5598854 - 12/31/12 10:34 PM

Quote:

How much more sensitive is the Samsung vs dslr ...? Can you exemplify to help me better understand the difference?

Considering the Sammy 2k is limited to 10s integration time, will a DSLR show much more after, let's say, a 60s exposure?




I don't think anybody actually measured the Samsung and various DSLR's sensitivity using a common test method, because a standard sensitivity test does not exist . Comparing measurements based on different tests carried on under different conditions would be misleading .

There are some examples of Mallincam (I know you asked about Samsung) images here:
http://mallincamproject.astrocpo.com/
However, the images are taken by different people with different gear so it's hard to make any direct comparison .

There are several aspects that will dictate the outcome of a DSLR vs. video cam comparison , and "sensitivity" is not the first of them .
The 2 most important issues are pixel size and CCD chip (diagonal) size .
Pixel size , winner is the video cam. A 1/2" or 1/3" CCD has a pixel area ranging from 32 um2 to 72 um2 (square microns ). A T2i has 18 um2 pixels . Assuming the same number of photons per unit of sensor area, the video cam receives 2 to 4 times more photons per pixel due just to this pixel size difference.
QE , Bayer filters , readout noise differences are very minimal .
Chip size matters and the winner here is NOT the larger size.
A 1/2" CCD has an 8mm diagonal, a 1/3" CCD has a 6mm diagonal. Canon T2i has a 26.6mm diagonal.
Let's assume you want to use the same scope and obtain the same field of view in order to frame the same subjects the same way in the video cam and the DSLR . The 1/2" CCD allows a focal ratio reduction 3.3 times more than the DSLR.
The 1/3" video cam allows a reduction of 4.4 times more than the DSLR.
Therefore , for the same scope and the same subject framing , the video cam receives 10 to 18 times more light per square micron of sensor area (goes up with the square of F reduction) .
Combine this 10 to 18 fold gain with the 2 to 4 times gain due to the larger pixel in the video cam and the result is the video cam pixels receive 20 to 32 times more light than the DSLR , for the same scope , same target and same image framing . Assuming similar QE , the video cam will capture an image on its sensor 20 to 32 times quicker than the DSLR . 17 sec max x 20 to 32 means 340 sec to 570 sec . What you see with the video cam in 17 seconds you will capture with the DSLR in 5 to 10 min .
This brings up another issue, which is the mount , with its tracking and polar alignment . You can get by with an alt/az setup and a quick and dirty polar alignment for 17 sec max exposure time but you need a good equatorial mount, good polar alignment (more time consuming) for 5 to 10 min . Then you also need to process the DSLR images , which adds even more time before you get to see the DSLR image .

Happy New Year


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mclewis1
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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5599874 - 01/01/13 03:54 PM

Oh I forgot to mention ... the Sony sensor in the Mallincam uses a CYMK vs RGB mask. The CYMK setup is also more sensitive.

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nytecam
Postmaster


Reged: 08/20/05

Loc: London UK
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mclewis1]
      #5600732 - 01/02/13 04:52 AM

I've the original Canon 300d DSLR and recently the entry level 1100d which much superior to the 300d in image quality and sensitivity but its still no match for the Sony HAD Exview CYMK sensor used in many CCTV/ astro-cams like Mallincam and SX Lodestar-C etc. All sensors are highly sensitive to near-IR radiation [galaxies radiate in IR too!] but in DSLRs this is blocked to preserve good colour.
But what is good colour in inordinately faint DSOs that doesn't register on the eye?
Quote:

Oh I forgot to mention ... the Sony sensor in the Mallincam uses a CYMK vs RGB mask. The CYMK setup is also more sensitive.


I've carried out comparative astro tests on my mono Lodestar and Lodestar-C one-shot-colour [OSC] cam that use Exview sensors and I rate the Lodestar-C @ ~60% the sensitivity of the Lodestar mono black&white cam so 60s mono needs a modest increase to 100s for similar image density but seen in glorious, if imperfect, colour

I've used both Lodestars on my astro-spectrograph and greater than one third of the radiation recorded is in near-IR which, with pale CYMK on-chip filters, greatly boosts the cam's sensitivity DSLR - no chance

Three recent DSO pics taken under a bright moonlight in Cigar Gxy, Bodes Gxy and Iris Neb



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ccs_hello
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Reged: 07/03/04

Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: nytecam]
      #5602128 - 01/02/13 11:08 PM

Videocams are still using complementary-color (CMY) then add G Bayer matrix while webcams and DSLRs, etc. now mostly use RGB (primary-color) Bayer array filter to get better color fidelity (which is mostly meaningless in astrophotography.)

The former has clear advantage over broadband spectrum emission objects. I.e., higher energy intake equals higher Signal output.

S/N stuff has a long story and many attributes to deal with. It's part of image science...

P.S. CMYK (K = black) is used in printing world for obstruct light reflection (absorb light). It's the opposite of let the light to shine in/pass through as in image sensors.

Clear Skies!

ccs_hello


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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: ccs_hello]
      #5602457 - 01/03/13 07:33 AM

If I understood well, after a similar 4 seconds exposure a cctv like Samsung SCB2000/4000 will capture much more light than a DSLR like Canon T2i.

Under these circumstances the next logical question is: in 8 seconds (or 512x) will the Samsung still capture much more light than the T2i exposed for 1-1.5 minutes?

If the final result is quite similar, than for me a Samsung CCTV investment is not worth it.

I use the dslr just to see more than in the eyepiece but NOT to take processed pictures. I don't have time or mood for stacking frames on PC or taking dark frames.

My CG5-GT unguided mount gives me quite round stars at maximum exposures of 1-1.5 minutes with a very good polar alignment.

Last night I discovered after 1 year that I can take my C11 down to F3.5 from F6 with the AlanGee telecompressor.


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mpgxsvcd
Carpal Tunnel


Reged: 12/21/11

Loc: Raleigh, North Carolina
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5603310 - 01/03/13 04:16 PM

Quote:

If I understood well, after a similar 4 seconds exposure a cctv like Samsung SCB2000/4000 will capture much more light than a DSLR like Canon T2i.

Under these circumstances the next logical question is: in 8 seconds (or 512x) will the Samsung still capture much more light than the T2i exposed for 1-1.5 minutes?

If the final result is quite similar, than for me a Samsung CCTV investment is not worth it.

I use the dslr just to see more than in the eyepiece but NOT to take processed pictures. I don't have time or mood for stacking frames on PC or taking dark frames.

My CG5-GT unguided mount gives me quite round stars at maximum exposures of 1-1.5 minutes with a very good polar alignment.

Last night I discovered after 1 year that I can take my C11 down to F3.5 from F6 with the AlanGee telecompressor.




Both sensors see the exact same light if the telescopes and focal reducers are the same. The real question is how much gain does each camera apply.

For the Samsung it might express the gain as 512x or a specific LUX number. The interchangeable Lens Camera will express it as a shutter speed and ISO exposure value.

If you can figure out how those numbers are equated then you can figure out which one needs more exposure time to make an equivalent picture.

In the cases I have seen it takes about ISO 12,800 for an interchangeable lens to equate to the good "video cameras". The T2i will not look good at ISO 12,800. The newest cameras will though.

You also have to look at the filter that is or is not used on the cameras and how much dynamic range each camera has.

The dynamic range on a large sensor camera is going to be vastly superior to that of the smaller sensor cameras. In the neighborhood of 2-8 stops.

However, the stock filter on most DSLR cameras will all but eliminate the Ha, UV, and IR light. That may or may not be taken out with the video camera.

If you are trying to image in UV, Ha, or IR spectrum then the video camera could possibly have 4-10 stops advantage. That would be huge. However, most of the interchangeable lens cameras can have their stock filter removed/replaced for a few hundred dollars.


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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mpgxsvcd]
      #5604020 - 01/04/13 02:38 AM

I see your point.

I was thinking of a max exposure of 512x (8s) for Samsung and one 1-1.5 minutes (no more because I don't autoguide, just use Celestron ASPA) exposure for Canon T2i at max ISO1600.

In my humble experience theres is no point to use a higher ISO with T2i because image is degrading at long exposures. I feel ISO800 is optimum for T2i for imaging DSOs.


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mclewis1
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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mpgxsvcd]
      #5604774 - 01/04/13 01:15 PM

Quote:

Both sensors see the exact same light if the telescopes and focal reducers are the same. The real question is how much gain does each camera apply.



While it's true that the same amount of light is falling on the surface of the sensor it is not the case that each sensor offers the same sensitivity so it's much more than just the gain the camera provides. Starting with a more sensitive sensor gets the camera's electronics more data or signal to work with. From that point the better gain and lower noise takes over to provide a better image of low light low contrast details. When someone is evaluating a camera for deep sky observing/imaging it's the sum of all the components (sensor, read amps, interface, cooling, packaging, power consumption, etc. etc.) that determines the more appropriate product.

Quote:

The dynamic range on a large sensor camera is going to be vastly superior to that of the smaller sensor cameras. In the neighborhood of 2-8 stops.



Travis, What cameras are you referencing? In general dynamic range doesn't have anything to do with the size of the sensor. It is simply the ratio between the signal and the noise. If you are starting out with more signal in each cell or pixel and are using similar low noise high gain electronics then you will have more dynamic range.

Quote:

However, the stock filter on most DSLR cameras will all but eliminate the Ha, UV, and IR light. That may or may not be taken out with the video camera. If you are trying to image in UV, Ha, or IR spectrum then the video camera could possibly have 4-10 stops advantage. That would be huge. However, most of the interchangeable lens cameras can have their stock filter removed/replaced for a few hundred dollars.



I agree, the filter situation does indeed make a big difference (Ha in particular is very important when viewing most extended nebula and galaxies). Security cameras usually come with a generally poor quality filter in place. Removing that filter can dramatically increase the amount of signal in those specific parts of the spectrum. Some security cameras offer an automated capability to slide the filter out of the way of the sensor, on others you have to physically remove the sensor completely. On the purpose built astronomy oriented cameras there usually is no filter at all. You then add back high quality, higher transmission and sometimes narrow band filters designed specifically for astronomy imaging.


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nytecam
Postmaster


Reged: 08/20/05

Loc: London UK
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: ccs_hello]
      #5604936 - 01/04/13 02:39 PM

Quote:

P.S. CMYK (K = black) is used in printing world for obstruct light reflection (absorb light). It's the opposite of let the light to shine in/pass through as in image sensors. Clear Skies!ccs_hello


Yep - I fell for that quote without checking - should read CYMG pixel matrix

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mpgxsvcd
Carpal Tunnel


Reged: 12/21/11

Loc: Raleigh, North Carolina
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mclewis1]
      #5610241 - 01/07/13 01:24 PM

Quote:


Quote:

The dynamic range on a large sensor camera is going to be vastly superior to that of the smaller sensor cameras. In the neighborhood of 2-8 stops.



Travis, What cameras are you referencing? In general dynamic range doesn't have anything to do with the size of the sensor. It is simply the ratio between the signal and the noise. If you are starting out with more signal in each cell or pixel and are using similar low noise high gain electronics then you will have more dynamic range.






Yes there is not a direct correlation to size of sensor and dynamic range. However, full frame sensor's almost always have more dynamic range than smaller sensors. There are a lot of factors in that though.

There are also many different definitions for dynamic range. I was using this definition from wiki.

"Dynamic range is the ratio between the largest and smallest possible values of a changeable quantity, such as in signals like sound and light. It is measured as a ratio, or as a base-10 (decibel) or base-2 (doublings, bits or stops) logarithmic value."

The common definition is that dynamic range is the ratio or number of stops from clipped white to clipped black.

14 bit RAW vs. 8 bit jpg(or equivalent), sensor technology...etc. Those all affect dynamic range. The Nikon D800 measured 14.4 EV with DXO mark. I know that their results are suspect but there are plenty of other tests that show cameras of that level achieve 13-14 stops.

The output format also affects dynamic range greatly. For instance there is a huge difference between 8 bit JPG and 14 bit RAW. So it really depends on how you are viewing the image. That is why I listed a broad range.

There is also the fact that some interchangeable lens cameras can do HDR images in camera and some can also do single exposure high dynamic range images. Those can simulate 1 to 2 extra stops.

Really there are so many different definitions and ways to test dynamic range that you can't accurately compare them. However, take equivalent images of Orion's nebula and let's see which camera blows out the core first. That should give you the results I stated.


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mpgxsvcd
Carpal Tunnel


Reged: 12/21/11

Loc: Raleigh, North Carolina
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mclewis1]
      #5610252 - 01/07/13 01:35 PM

Quote:

Quote:

Both sensors see the exact same light if the telescopes and focal reducers are the same. The real question is how much gain does each camera apply.



While it's true that the same amount of light is falling on the surface of the sensor it is not the case that each sensor offers the same sensitivity so it's much more than just the gain the camera provides. Starting with a more sensitive sensor gets the camera's electronics more data or signal to work with. From that point the better gain and lower noise takes over to provide a better image of low light low contrast details. When someone is evaluating a camera for deep sky observing/imaging it's the sum of all the components (sensor, read amps, interface, cooling, packaging, power consumption, etc. etc.) that determines the more appropriate product.





The problem with this theory is that it just assumes that one camera is more sensitive than the other. You just state that one camera is more sensitive than the other.

Given the same exposure settings(Aperture, Shutter Speed, and sensitivity gain) the images will only differ in resolution, noise, and dynamic range. Their exposures will be the same.

The issue is that we don't know what sensitivity gain(ie: 512x) on the specialized cameras equates to the same sensitivity gain(ISO) on the interchangeable lens cameras. We can only guess without a 1:1 comparison.

I propose that we do that test. I for one would love to see a specialized camera and a newer interchangeable lens camera compared with the exact same setup. I don't want to do it to say this camera is better than another. They all have their strengths and weaknesses.

I just want to figure out what the strengths and weaknesses are of each camera so we know better how to utilize them. For instance something with greater dynamic range will probably give you a better image of M42 while something with high Ha sensitivity will give you a better image of the Horse Head.

I just would like to see some concrete samples they show the differences instead of vague generalizations that one camera is "More Sensitive" than another so it must be better for everything.

I am willing to run the test I just need some other cameras to test it with. I would even drive a distance with my equipment to meet someone if you live in the North Carolina Region.


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mclewis1
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Reged: 02/25/06

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mpgxsvcd]
      #5610366 - 01/07/13 02:48 PM

Travis,

I'm with ya 100% on both posts.

The "more sensitive" comment is about the sensor, not the camera. The "more sensitivity sensor" is the Sony ICX 428AKL (ExView HAD) chip. With a sensitivity of 1600mv (from those big 8.4 x 9.8 um cells and CYMK filters) any camera that starts off with that chip is going to have a leg up on just about anything else out there ... and then of course there's the pre amp/amp gain, A/D conversion (and bit depth), noise reduction, etc. etc.


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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mclewis1]
      #5611774 - 01/08/13 11:23 AM Attachment (55 downloads)

The image of M31 below is taken by me with a C11 at F3.5 with AlanGee telecompressor on a CG5-GT and Canon 550D. This is not processed or stacked at all and unguided too, at ISO 3200 and a single 120s exposure. The 550D was set with High Iso Reduction on AUTO.

Can a LNTECH-300 show me much more on M31 after an exposure of 17/20s (1024x) with the same telescope?


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5611793 - 01/08/13 11:38 AM

you can't get M31 to fit on a Samsung or Lntech sensor with the same telescope and same reducer. You need to reduce the focal length another 4 times to match the same field of view as in your 550D image.

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mpgxsvcd
Carpal Tunnel


Reged: 12/21/11

Loc: Raleigh, North Carolina
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5611817 - 01/08/13 11:56 AM

Quote:

you can't get M31 to fit on a Samsung or Lntech sensor with the same telescope and same reducer. You need to reduce the focal length another 4 times to match the same field of view as in your 550D image.




An 11" F.875 telescope would be really cool.


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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mpgxsvcd]
      #5611844 - 01/08/13 12:18 PM

Ok,but I wasn't referring to the field of view. I was referring to the amount of detail (like arms, color, etc) captured on M31. My mistake I wasn't clear enough.

I realize that FOV with a CCTV will be smaller even if I didn't know how much smaller.


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mpgxsvcd
Carpal Tunnel


Reged: 12/21/11

Loc: Raleigh, North Carolina
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5611857 - 01/08/13 12:24 PM

Quote:

Ok,but I wasn't referring to the field of view. I was referring to the amount of detail (like arms, color, etc) captured on M31. My mistake I wasn't clear enough.

I realize that FOV with a CCTV will be smaller even if I didn't know how much smaller.




The field of view between the CCTV camera and APS-C is so different that the objects would not be similar at all. The difference really is quite significant when dealing with large objects like M31.

The larger sensor will fit the object in the field of view. The smaller sensor simply won't.


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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mpgxsvcd]
      #5611895 - 01/08/13 12:51 PM

Dame, I haven't made myself clear again.

In this case, to be more clear, let's replace M31 with a faint and small DSO and keep the same question.


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ccs_hello
Postmaster
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Reged: 07/03/04

Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5612558 - 01/08/13 07:18 PM

All image devices have multiple attributes to compare with. To make a fair comparison, some test conditions must be normalized first and there is no clear winner on all fronts.

At the end of day, it's all tradeoffs. Many situations seen in this subforum have been S/N vs. fast(er) image acquisition time debate.

Price, better S/N, or fast image acquisition time, can only pick two. <-- Did you notice I didn't even bother to use a quite "polluted" term: sensitivity?

Clear Skies!

ccs_hello


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nytecam
Postmaster


Reged: 08/20/05

Loc: London UK
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5613137 - 01/09/13 04:32 AM

An impresive M31 via DSLR single shot Moromete

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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: nytecam]
      #5613524 - 01/09/13 11:21 AM

Thank you Nytecam! We both know it's not so impressive when compared to others M31 shots.

For me it really is impressive because I have no experience in astrophoto, I have no guiding camera, I have used a C11 on CG5-GT pier mounted (not even an EQ6/Atlas) and I don't do image stacking or dark frames because of lack of time and mood.
Oh and I don't take a laptop outside with me.
I would like to have a DSLR to do everything for me, including stacking and dark frame subtraction, and let me see the beauties in the sky with ease and fast.

Someday maybe I'll buy an autoguider but I don't know if it resumes the guiding process automatically after changing different GOTO targets during the night. I don't see myself to setup the autoguider every time I enter a new GOTO target in the hand controller. I'm more a visual observer.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5613659 - 01/09/13 12:38 PM

Is the following combination usable: SCT + Meade f/3.3 reducer + inexpensive 1.25" 0.5x reducer + Lntech300/Samsung SCB-2000?

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5613905 - 01/09/13 03:11 PM

Usable but not pretty. The combo of the two will exacerbate their faults like coma and vignetting. It would depend on your tolerance of these aberrations when viewing. I tried a cheaper 0.5X focal reducer in combo with a 6.3 focal reducer and found the amount of coma objectionable. I have had good luck using an older version of Meade's 3.3 reducer and a two inch extension tube (Teleview) to achieve even more reduction without too much aberration but the quality of them is variable and I just was lucky. They still work better than the 0.5X variety as coma, although present, is just the outer edge of the field. Check the images I have posted as I used this combo for all but the last ones where I tried out the Mallincam reducer (also an option but pricey).

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Dwight J]
      #5613934 - 01/09/13 03:31 PM

I agree with Dwight, the f3.3 reducer on it's own would likely be my choice. I've also stacked different focal reducers and found that the f6.3 and one of the .5x 1.25" reducers can work but doesn't look particularly good at the edges. Different .5x reducers will produce different results as well. I've also tried a .5x 2" reducer with better results but the f3.3 reducer by itself is still my first choice.

With the f3.3 reducer you can use a 1.25" visual back and 1.25" nosepiece on the camera. It can also be useful to remove the external threads on 1.25" visual back to reduce the amount of spacing. With this reducer I prefer to use T thread spacers and a T - C mount adapter on the camera ... this makes for an all threaded robust connection.

http://agenaastro.com/blue-fireball-t-thread-female-c-mount-male-adapter.html


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mclewis1]
      #5613978 - 01/09/13 04:02 PM

Thanks for your feedback guys.

I see you both have experience in stacking a 0.5x reducer after the f6.3 reducer and prefer the Meade f3.3 reducer instead of this combo because of less coma with an SCT.

But has anyone tried a 0.5x reducer after a Meade f3.3 reducer with an SCT and a CCTV?


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5614059 - 01/09/13 04:44 PM

It would be fun to try that combination. It will be very fast and therefore will have very steep light cone angles so filters may be a big problem and there will be severe light drop off (vignetting) at the edges. The in focus travel required to come to focus could be an issue too.

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mclewis1]
      #5614491 - 01/09/13 08:57 PM

Quote:

It would be fun to try that combination. It will be very fast and therefore will have very steep light cone angles so filters may be a big problem and there will be severe light drop off (vignetting) at the edges. The in focus travel required to come to focus could be an issue too.



I am using the Meade x.33 reducer on the scope combined with a x.05 1.25" redcuer on the camera (replaces the nose piece) . It's the only way to get all the field of view the SCT has , which is very narrow to begin with.

It's true that there's some vignetting and coma at the field edges but this tiny video cam ccd doesn't see that far to the edges .

A simple test is to remove just the camera from the setup , but with all reducers in place on the scope .
Place a white sheet of paper at the sensor plane (the distance from the x.5 reducer back where the camera ccd window should be .

You can easily see looking thru the paper what is the illuminated area and how is it vignetting especially f you use the full moon projected on the paper.

I found out I can get the maximum reduction with the Meade reducer threaded straight into the back of the scope , as close to the scope as possible . The farther the reducer is from the scope, the less reduction you get.

Based on some field of view measurements I get my 8" and 10" SCT's down to F2.2 to F2.3 .

I have an adjustable extension between the Meade reducer and the camera 1.25" reducer .

I rotate the scope focuser all the way to the end and back off one turn. Then slide in the camera and adjust the variable extension until I reach close to focus. I secure the variable extension to that exact size and from there on focus normally using the scope focuser (by moving the primary). No microfocusers attached, just the reducer straight onto the scope back.

I placed a 2" light pollution filter in front of the Meade reducer around Christmas due to horrendous Christmas lights throught my neighborhood .

Forget about coma . The image scale is about 6-8 arcsec/pixel anyway so you won't see only some bigger stars due to coma, you'll see all stars bigger due to the image scale.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5614793 - 01/10/13 01:00 AM

And there's one additional point ...

Those of us with a Mallincam and SCB4000 cameras have the slightly larger 1/2" sensors, those with the 435/2000 and LnTech cameras have the slightly smaller 1/3" sensors. This makes a difference when your are evaluating the edge performance with various focal reducers. Those using the 1/3" sensors won't have as much to complain about.

Edited by mclewis1 (01/10/13 01:01 AM)


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mclewis1]
      #5614944 - 01/10/13 06:45 AM

Excellent news mattflastro!

What do you say about this camera http://www.bavono.com/eng/BVO616S.html ?

It has Sony ExView HAD CCD II, Sense-Up x1024 and AGC user selectable up to 36db (unlike Lntech or Samsung).

Problem is I can't find someone to sell it around the world.
Maybe we should Aliexpress to put it on their website because they already sell Bavono products! What do you think?


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5615103 - 01/10/13 09:17 AM

Quote:

Excellent news mattflastro!

What do you say about this camera http://www.bavono.com/eng/BVO616S.html ?

It has Sony ExView HAD CCD II, Sense-Up x1024 and AGC user selectable up to 36db (unlike Lntech or Samsung).

Problem is I can't find someone to sell it around the world.
Maybe we should Aliexpress to put it on their website because they already sell Bavono products! What do you think?



I downloaded the user manual for that camera and it doesn't say anywhere MANUAL GAIN or FIXED GAIN, only AGC OFF and ON .

From the sketchy info in that one page manual the only thing you can set manually is a maximum limit for the AGC , similar to the EFFIO-S and P camera DSP's from Sony . The same idea as in setting SENSE-UP to ON and selecting a max value . The camera does whatever it wants up to that value . You can't force it to use the maximum as a fixed value .


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5615111 - 01/10/13 09:28 AM

Quote:

Quote:

Excellent news mattflastro!

What do you say about this camera http://www.bavono.com/eng/BVO616S.html ?

It has Sony ExView HAD CCD II, Sense-Up x1024 and AGC user selectable up to 36db (unlike Lntech or Samsung).

Problem is I can't find someone to sell it around the world.
Maybe we should Aliexpress to put it on their website because they already sell Bavono products! What do you think?



I downloaded the user manual for that camera and it doesn't say anywhere MANUAL GAIN or AGC OFF or FIXED GAIN .

From the sketchy info in that one page manual the only thing you can set manually is a maximum limit for the AGC , similar to the EFFIO-S and P camera DSP's from Sony . The same idea as in setting SENSE-UP to ON and selecting a max value . The camera does whatever it wants up to that value . You can't force it to use the maximum as a fixed value .



I also forgot to mention that Sony Effio AGC goes up to 42dB , that's double the gain . Cameras that do only 36dB have a reason for it, and the reason is poor AFE performance . No sense in amplifying noise .Also, case looks plasticky . Maybe it's a good camera but cooling in a plastic enclosure will be problematic.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5615213 - 01/10/13 10:37 AM

Mattflastro I think you wrong this time regarding Bavono cctv Gain and enclosure.

Here is the manual http://www.bavono.com/Download/3044200337_BVO616S%20Manual(eng).pdf .

In the tiny product manual/specifications says that AGC = Off~36dB(3dB unit). I think this means you can increase the gain in steps of 3dB up to 36dB. Regarding Sony Effio I agree with you.
Regarding camera's enclosure, in the tiny product manual/specifications says Shell Material = Metal, not plastic.
Isn't this better Lntech300's AGC which is kept on Off because isn't user adjustable in different steps like Bavono is?!

Now shoot and correct me if I'm wrong.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5615465 - 01/10/13 12:51 PM

The guy selling these assures me they are the camera you are after. Comes with a lens. Not as cheap as the $70 ones but is it really better? Looks like it has network capability!

Quote

"BVO616S OR BVO616W They are the same, looking forward to your reply.
lens3.5-8mm

zesan yi"

http://www.aliexpress.com/item-img/BAVONO-CCTV-700TVL-OSD-Menu-Ultra-WDR-Gun-...


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: telfish]
      #5615485 - 01/10/13 01:00 PM

No, it's not the same product. Aliexpress sells model BVO616W (with Sense-Up only 512x) and we need BVO616S (with Sense-Up to 1024x and AGC user adjustable 3dB steps).

Yes, it seems to have a lens and a metal enclosure, not plastic.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5615571 - 01/10/13 01:42 PM

These are the specs he is quoting me at the same price as the W model.

BVO616S

Ultra High Resolution Wide Dynamic Range Box Camera

Features

1/3" Sony Ex-view HAD CCD II Image Sensor
Digital Wide Dynamic Range
Horizontal resolution of up to 700 TVL
Sens-up X1024 & minimum illumination of 0.0001 lux
Built-in automatic IR cut filter
Day/night mode to enable 24 hour continuous surveillance
8 times digital zoom
48 zones motion detection
24 zones privacy masking
Intelligent 3D DNR for reducing HDD capacity
Built-in OSD
Built-in balun
Supports dual power supply: DC 10V - 40V / AC 7V - 40V
Specifications

Model BVO616S
Video Standard NTSC PAL
Image Sensor SONY 1/3" Ex-view HAD CCD II
Total Picture Elements 1020(H) X 508(V) 1020(H) X 596(V)
Effective Picture Elements 976(H) X 494(V) 976(H) X 582(V)
Horizontal Resolution 700 TVL
Min. illumination (approx.) Color&#65306;0.1 Lux@F1.2(50IRE) / 0.0001 Lux(Sens Up On)
B/W&#65306;0.08Lux@F1.2(50IRE) / 0.00008 Lux(Sens Up On)
Synchronizing System Internal, AC Line Lock
Video S/N Ratio 52dB
Digital Zoom 8X
Day / Night AUTO / DAY / NIGHT / EXT1 / EXT2
High Speed Shutter 1/60(1/50) ~ 1/15K
Flickerless Mode ON / OFF
Digital Wide Dynamic Range OFF / HIGH / MID / LOW
Auto Gain Control (AGC) Off ~ 36dB (3dB Unit)
IR-Cut Filter Built-in
Iris ALC(DC Auto Iris) / ELC(Off/On ( ~ 1/200K sec))
Sens-up X 1,024
Smart IR OFF / ON
White Balance ATW1 / ATW2 / AWC / MANUAL / INDOOR / OUTDOOR
Digital Noise Reduction (2D+3D) HIGH / MID / LOW
Camera ID OFF / ON (Max. 20 char per line)
Motion Detection 48 Zones
Privacy Masking 24 Zones
Backlight Compensation (BLC) OFF / BLC / HLC
Options DIS, PAN/TILT
Video Output VBS 1.0V p-p (75ohm Terminated)
Fast Connection Built-in Balun
OSD Language English / Simplified Chinese / French / Portuguese / Spanish / Japanese / German / Russian
Power Input DC 10V - 40V / AC 7V - 40V
Power Consumption Less than 1.5W
Operating Temperature &#8208;10C ~ +50C
Operating Humidity Less than 90%
Shell Material Metal
Dimensions (mm) 107 x 61 x 55
Gross Weight (g) 531


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Moromete
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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: telfish]
      #5615630 - 01/10/13 02:22 PM

Make me understand please. He is selling both models or he says W model he sells is identical to S model which isn't on Aliexpress?

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5615643 - 01/10/13 02:30 PM

Yep,

He is saying that although the specs he gave me are different the camera and price is the same!

Latest confirmation.

Dear terry
BVO616S $187
regards
zesan yi

So who is going to be brave enough to be the one brave enough to order one?


Terry


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Moromete
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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: telfish]
      #5615661 - 01/10/13 02:41 PM

Than why isn't BVO616S on Aliexpress website?

That's strange. I don't trust chinese.


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telfish
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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5615663 - 01/10/13 02:42 PM

And that is the mystery!

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: telfish]
      #5615670 - 01/10/13 02:48 PM

Thx for info.

Tell him to put BVO616S on Aliexpressss website and than we'll order it. If he wants to sell it he has to make the ordering process clear and transparent for the customer. Push him to do it because he has an interesting product. Ask him if will remove the IR filter on request.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5615739 - 01/10/13 03:35 PM

Will do.

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: telfish]
      #5616640 - 01/11/13 03:38 AM

Quote:

Yep,

He is saying that although the specs he gave me are different the camera and price is the same!

Latest confirmation.

Dear terry
BVO616S $187
regards
zesan yi

So who is going to be brave enough to be the one brave enough to order one?


Terry



Guys,
Before jumping head first and buying sight unseen an unknown $200 camera, take a moment and reason a little:

- this camera has exactly the same specs as the Lntech and a million others .
- it does NOT have FIXED MANUAL GAIN .
- the manual clearly states AGC adjustable in steps of 3 dB . It doesn't say MGC in 3dB steps . For people not used with electronics specifications, this might sound the same as manual gain but it is not.
- AGC adjustable in steps of 3dB simply means YOU SET THE AUTOMATIC GAIN CONTROL LIMIT in 3dB increments . The camera is still doing AGC = AUTOMATIC GAIN CONTROL . The value you set is the maximum gain the AGC is allowed to use , starting from the lowest value that's possible in that camera. It doesn't do AGC within a 3dB window . An AGC confined to a 3dB window doesn't exist .
- in order for a camra to have manual gain control, the specification should say something like AGC = OFF/MANUAL/AGC STEPS of 3dB , or OFF/FIXED 3dB steps/AGC 3dB steps . This camera DOES NOT HAVE MANUAL GAIN CONTROL.
- in order for a camera to be usable for astro it needs other qualities as well, such as :
- adjustable GAMMA
- low noise circuits , especially AMP-GLOW elimination. Security video cams have ALL amp-glow as made by the factory .

Fortunately there is a very easy and simple way to tell if this camera is worth buying .
ASK THE VENDOR WHAT DSP is inside the camera. There aren't that many DSP makers and models on the market and their specs are available in much greater detail than a single page camera datasheet . Once you know the DSP model, we can find its user manual, see the details of the OSD menu and exactly what the camera does.
I would NEVER buy a camera without knowing what DSP in used in it .

Good luck with your camera buy and please report back if the camera lived up to your expectations of manual gain.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5616712 - 01/11/13 05:33 AM

Damn it, you must be right again!

Your technical explanation seems logical.

I thought I was right because in the tabel from here http://www.aliexpress.com/item/BAVONO-CCTV-700TVL-OSD-Menu-Ultra-WDR-Gun-Box-... says AGC = Level Setting.
Than I saw on Bavono's website that AGC is adjustable 3dB steps and I concluded that you set it manually with a fixed value.
I haven't thought that by level setting you establish only the upper limit and the AGC fluctuates as it wants between odB and user's fixed upper limit.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5616798 - 01/11/13 07:59 AM

Quote:

Damn it, you must be right again!

Your technical explanation seems logical.

I thought I was right because in the tabel from here http://www.aliexpress.com/item/BAVONO-CCTV-700TVL-OSD-Menu-Ultra-WDR-Gun-Box-... says AGC = Level Setting.
Than I saw on Bavono's website that AGC is adjustable 3dB steps and I concluded that you set it manually with a fixed value.
I haven't thought that by level setting you establish only the upper limit and the AGC fluctuates as it wants between odB and user's fixed upper limit.




Oh well, if anyone still wishes to try it here is the buying link. I will ask him what DSP is in it just in case someone is interested.

http://www.aliexpress.com/store/product/Ultra-High-Resolution-Wide-Dynamic-Ra...


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: telfish]
      #5616855 - 01/11/13 08:52 AM

Excellent job tellfish! Bravo!

If possible besides DSP, ask him the AGC is manual or works like mattflastro explained.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5622194 - 01/14/13 07:11 AM

What do you say about these models guys:

http://www.cameras-cctv.com/fs/doc/product/58ep-july-18-2012-manual.pdf

http://www.dahuasecurity.com/products/ca-f781e--92.html


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5622334 - 01/14/13 09:38 AM

Quote:

What do you say about these models guys:

http://www.cameras-cctv.com/fs/doc/product/58ep-july-18-2012-manual.pdf

http://www.dahuasecurity.com/products/ca-f781e--92.html




The first one appears to still have only AGC , no manual settings. It also appears to have only x512 sens-up in auto mode, not manual. When you set sens-up to x512, the camera doesn't do 512 . It does what it decides in order to have the average image exposed the way it decides. The samsung or lntech are used by setting sens-up to off and setting exposure to slow shutter mode, user set value up to x1024 ( lntech ). This camera doesn't have a slow shutter manual setting .

The second camera has a Sony Effio-S DSP. I have such a camera and tested it a lot. I really wanted to make it work because the Sony name is a better guarantee of quality than Lntech for example. But the camera doesn't want to cooperate. The Effio DSP suffers from some excessive DSP processing that quickly saturates the bright areas of the image and makes it lose all color . Again, it's the DSP attempting to bring the whole screen average brightness to certain levels that may be useful for a surveillance video camera but it kills all color and washes out detail for astro. There is a slightly better version, Effio-P , which goes to x512 sens-up (the Effio-S only does x256 ) and due to the longer time , lower AGC can be used but it's still basically the same problem.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5622481 - 01/14/13 11:15 AM

I have read on forums that Dahua makes better quality products, as are in general Korean products than Chinese ones (at least that's my impression).

OK, than what about this one http://www.d-max.co.kr/product/manual/dcc-600f.pdf ?

D-MAX camera's AGC seems to be manual so maybe the cctv could be more useful at 512x with AGC On than Lntech at 1024x with AGC Off.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5622503 - 01/14/13 11:28 AM

Quote:

I have read on forums that Dahua makes better quality products, as are in general Korean products than Chinese ones (at least that's my impression).

OK, than what about this one http://www.d-max.co.kr/product/manual/dcc-600f.pdf ?

D-MAX camera's AGC seems to be manual so maybe the cctv could be more useful at 512x with AGC On than Lntech at 1024x with AGC Off.



I spoke with those guys about 2 months ago. The AGC is not manual , sens-up only to x512 . They use a little known Korean DSP K-600 or KC-600 (don't recall exactly off the top of my head). Feature set seems about the same as all the others.
As far as Lntech being Chinese, all I have to say is that I don't really know who makes what parts of those cameras. The DSP is designed by a Korean company . The vendors I dealt with when buying Lntech stuff are in Hong-Kong .The stuff I received from them came from Korea and Hong-Kong based on the waybills , customs declarations that were attached etc.


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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5622514 - 01/14/13 11:34 AM

Please help me understand. Look at page no. 13 in D-Max manual. Since you can set AGC at 0-255 that means AGC is still not manual?

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5622602 - 01/14/13 12:34 PM

Quote:

Please help me understand. Look at page no. 13 in D-Max manual. Since you can set AGC at 0-255 that means AGC is still not manual?



AGC means automatc gain control and is not manual. The only difference between all the cameras you found is the number and size of steps that the upper limit of gain can be set by the user for the AGC . Typical AFE chips have programmable gains in the range of 36 to 46 dB in very small increments, as low as 0.1 dB and in some cases 0.015dB . That is roughly 300+ to 3000+ microsteps to set the AGC upper limit, so the DSP programmers decided to split this huge and useless number of steps into fewer larger ones , hence the low/mid/high variations , 0 to 100 or 0-255 . Please understand this, there is no more manual gain on current video surveillance cameras since the advent of onboard ARM based 32 bit DSP-s with OSD .


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Moromete
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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5622610 - 01/14/13 12:43 PM

Now I understood. Thank you for explaining. AGC myth busted!

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Moromete
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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5629276 - 01/18/13 02:27 AM

Does any Android application exist which allows the user to transform his Android device in a portable LiveView DVR for his CCTV/ analog astro camera by means of a USB cable connection?

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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5629424 - 01/18/13 07:16 AM

Quote:

Does any Android application exist which allows the user to transform his Android device in a portable LiveView DVR for his CCTV/ analog astro camera by means of a USB cable connection?



I don't know of any Android supported USB frame grabber .
However, there are other devices that record analog video on Flash memory cards.


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Moromete
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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mattflastro]
      #5629597 - 01/18/13 10:06 AM

Yes, I know there are other devices. I have found a mini DVR with a 3.5" LCD an AV IN.
But it would be wonderful and cost effective to be able to connect everything in astronomy to your phone (Android or iPhone) and not to be forced to buy new devices for different applications in astronomy.
In other words I'm looking for a laptop substitute in my Android phone considering it has GPS,etc.

Just imagine a Lntech300 camera connected to your phone through a cable which replaces a TV and a separate recorder or a laptop or even become an autoguider. You have the phone all the time with you in your pocket.

Can CCTVs be used for autoguiding? Is any software available for this?


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5629762 - 01/18/13 11:31 AM

Quote:

Yes, I know there are other devices. I have found a mini DVR with a 3.5" LCD an AV IN.
But it would be wonderful and cost effective to be able to connect everything in astronomy to your phone (Android or iPhone) and not to be forced to buy new devices for different applications in astronomy.
In other words I'm looking for a laptop substitute in my Android phone considering it has GPS,etc.

Just imagine a Lntech300 camera connected to your phone through a cable which replaces a TV and a separate recorder or a laptop or even become an autoguider. You have the phone all the time with you in your pocket.

Can CCTVs be used for autoguiding? Is any software available for this?



current Android phones are still far from capable of accomplishing what you envision . For one thing, the analog cameras need power that the phone can't supply. The USB frame grabber (no analog video input on Android phones) needs USB power too and I don't know of any phones that could support it . IF you want a real , reliable working solution, that's still in the hypothetical future . Maybe Ubuntu for smartphones will provide support for the type of stuff you want but not now.


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mclewis1
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Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5629776 - 01/18/13 11:39 AM

Quote:

Can CCTVs be used for autoguiding? Is any software available for this?



Yes. Because the video connection goes through a USB frame grabber you won't find support for specific video cameras in the autoguiding software ... but since the frame grabber creates a Windows web cam like video stream most autoguiding software can work with it.

The downside is that on low end cameras there can be quite a few warm/hot pixels and quite a bit of background noise which makes autoguiding sometimes a bit tricky. The slight shift in video sync between frames also prevents these cameras from being used as very accurate autoguiders but over all they do work.


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ccs_hello
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Reged: 07/03/04

Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: mclewis1]
      #5631249 - 01/19/13 10:14 AM

Android OS natively does not have USB webcam device driver(s) built in, let along the very high bandwidth demanding (cheap) USB video dongle (need isochonous transfer at USB 2 high-speed mode). If you are an experienced XDA Developer, you might be able to build a custom kernel to support the former, but almost impossible to support the latter class.

For IOS, it's much harder since it's a closed OS.

I have used smart-device's "USB Host mode" to support low-bandwidth easy devices (USB microphonee and USB audio device). I also know how to inject power and did so in the connection (now every newer devices with latest OS version who support it) will require it (i.e., smart device will not supply power). <-- If you want to know more, read my CN post in Software forum here.

P.S. for video dongle, even a low-end PC made few years back (e.g., Intel low-end Pentium 4) won't support it well (hickups). A smartphone, after all, is a smartphone (portable device).

P.P.S. OFF (the original) TOPIC discussions should start a new thread!!!

Clear Skies!

ccs_hello


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Samsung SCB-4000/2000 vs Canon T2i sensitivity new [Re: Moromete]
      #5632284 - 01/19/13 09:57 PM

Quote:

Yes, I know there are other devices. I have found a mini DVR with a 3.5" LCD an AV IN.
But it would be wonderful and cost effective to be able to connect everything in astronomy to your phone (Android or iPhone) and not to be forced to buy new devices for different applications in astronomy.
In other words I'm looking for a laptop substitute in my Android phone considering it has GPS,etc.

Just imagine a Lntech300 camera connected to your phone through a cable which replaces a TV and a separate recorder or a laptop or even become an autoguider. You have the phone all the time with you in your pocket.

Can CCTVs be used for autoguiding? Is any software available for this?



you could control your Canon DSLR with your Android phone assuming it's a recent phone and you would have live-view and remote focus with it together with all other camera functions :

http://dslrcontroller.com/


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