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What can you do in 10 to 30 seconds?

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#26 CharlesC

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Posted 04 February 2019 - 12:43 PM

Hi Steve,

 

CCD's being faster than CMOS is not a myth.  Saying that CMOS have caught up and are faster than CCD is the myth.  Everyone has become brainwashed into thinking CMOS is more sensitive because of the beautiful images full of rich detail that they can produce, not realizing that in fact they are taking way longer to get that image.  The problem is that all the images that are posted from CMOS cameras are stacks, while all the images posted from CCD cameras are single exposures.  That is not a fair comparison.  I have done a bucket-load of tests, with dozens of camera models, and for a single exposure CCD's still produce the best SNR...reworded another way, CCD's produce the shortest Time To Observable Image.  Specifically the ICX828 CCD still blows everything else away, by more than a factor of 10.  Slowly I am putting all my testing together to present to the community, it is just taking a lot of time to do correctly.  Please stay tuned, I am on it!

 

Cheers,

 

Jim T.

 

My empirical judgement is that most sensitive CMOS takes double the time of the most sensitive CCD.  I looked at what folks were doing with ASI224 a long time and compared it to times for my CCD Revolution2/LN300.  The new higher resolution CMOS look much better, but requires a more accurate mount because of the doubling of required exposures.  That said, I hope to upgrade to CMOS soon after being on sidelines for a couple of years.


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#27 Don Rudny

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Posted 04 February 2019 - 07:57 PM

Hi Steve,

 

CCD's being faster than CMOS is not a myth.  Saying that CMOS have caught up and are faster than CCD is the myth.  Everyone has become brainwashed into thinking CMOS is more sensitive because of the beautiful images full of rich detail that they can produce, not realizing that in fact they are taking way longer to get that image.  The problem is that all the images that are posted from CMOS cameras are stacks, while all the images posted from CCD cameras are single exposures.  That is not a fair comparison.  I have done a bucket-load of tests, with dozens of camera models, and for a single exposure CCD's still produce the best SNR...reworded another way, CCD's produce the shortest Time To Observable Image.  Specifically the ICX828 CCD still blows everything else away, by more than a factor of 10.  Slowly I am putting all my testing together to present to the community, it is just taking a lot of time to do correctly.  Please stay tuned, I am on it!

 

Cheers,

 

Jim T.

Thanks for this info, Jim.  I still find the Lodestar with the Sony 829 (Pal version of the NTSC 828) sensor the go to for viewing dim objects quickly.  Resolution may not be the greatest, but you get to see a lot in some unique faint objects.  There were some like Martin Meredith and the late Nytecam who did wonders with their Lodestars, especially the mono, and posted results here.

 

Don


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#28 DSO_Viewer

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Posted 04 February 2019 - 08:54 PM

Hi Steve,

 

CCD's being faster than CMOS is not a myth.  Saying that CMOS have caught up and are faster than CCD is the myth.  Everyone has become brainwashed into thinking CMOS is more sensitive because of the beautiful images full of rich detail that they can produce, not realizing that in fact they are taking way longer to get that image.  The problem is that all the images that are posted from CMOS cameras are stacks, while all the images posted from CCD cameras are single exposures.  That is not a fair comparison.  I have done a bucket-load of tests, with dozens of camera models, and for a single exposure CCD's still produce the best SNR...reworded another way, CCD's produce the shortest Time To Observable Image.  Specifically the ICX828 CCD still blows everything else away, by more than a factor of 10.  Slowly I am putting all my testing together to present to the community, it is just taking a lot of time to do correctly.  Please stay tuned, I am on it!

 

Cheers,

 

Jim T.

Jim, I think that the only main reason most will find a ccd sensor faster than a cmos sensor is because these tiny ccd sensors can be used at very fast focal ratios where one can use a Meade 3.3 reducer or double stack a 6.3 reducer. Most cmos are much larger and cannot be reduced down due to severe vignetting issues thereby making scopes much slower.

 

Steve



#29 DSO_Viewer

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Posted 04 February 2019 - 09:00 PM

Jim, I think that the only main reason most will find a ccd sensor faster than a cmos sensor is because these tiny ccd sensors can be used at very fast focal ratios where one can use a Meade 3.3 reducer or double stack a 6.3 reducer. Most cmos are much larger and cannot be reduced down due to severe vignetting issues thereby making scopes much slower.

 

Steve

Also Jim you mention that cmos sensors require stacking but did not the Mallincam extremes and Starlight Lodstars having ccd's use stacking software like Miloslick and Starlight Live to enhance their views?

 

Steve


Edited by DSO_Viewer, 04 February 2019 - 09:00 PM.


#30 jimthompson

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Posted 04 February 2019 - 09:44 PM

Thanks for this info, Jim.  I still find the Lodestar with the Sony 829 (Pal version of the NTSC 828) sensor the go to for viewing dim objects quickly.  Resolution may not be the greatest, but you get to see a lot in some unique faint objects.  There were some like Martin Meredith and the late Nytecam who did wonders with their Lodestars, especially the mono, and posted results here.

 

Don

Hi Don,

 

Sorry but when you say "the late Nytecam", are you saying he passed away?  If so I had not heard that.  What a great loss to the EAA community.

 

Regards,

 

Jim T.



#31 jimthompson

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Posted 04 February 2019 - 09:52 PM

Also Jim you mention that cmos sensors require stacking but did not the Mallincam extremes and Starlight Lodstars having ccd's use stacking software like Miloslick and Starlight Live to enhance their views?

 

Steve

Hi Steve,

 

Yes you can use stacking with MC Xtremes/Xterminators and Lodestars, but for many the mode of operation has always been single exposures, especially for the analog video type cameras.  That is what I'm talking about here, the fact that you don't need to stack multiple frames to get your observable image when you use a CCD.  Try for yourself a single 20 or 40 sec exposure with a CMOS camera and pretend like that is all you have to work with, no stacking.

 

With regards to focal reducers, you are correct that the larger sensors that are popular now amongst CMOS camera users tend to limit how fast an optical system you can use, that is an additional affect.  All my testing has been at the same f-ratio.

 

Best Regards,

 

Jim T.


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#32 Don Rudny

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Posted 04 February 2019 - 09:57 PM

Also Jim you mention that cmos sensors require stacking but did not the Mallincam extremes and Starlight Lodstars having ccd's use stacking software like Miloslick and Starlight Live to enhance their views?

 

Steve

Steve,

 

Just addressing the Lodestar, I usually stacked in SLL or Lodestar Live as it was initially called, but usually only 3-5 stacks to improve the first image that was pretty good.  I think Mallincam usually did a single direct to monitor and Miloslick added the stacking option when using a computer.  Stacking reduces the random noise signal that will improve the SNR or any camera.  I’m sure that Jim can elaborate on this.  Sensor speed needs to be addressed in a manner that uses the same optics speed to address your previous comment, but I would defer to Jim on the details of how that is done.  I do recall that Sony published mv output at specific f stops for sensors and the 828/829 sensor was one of, and maybe the highest.

 

Don


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#33 Don Rudny

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Posted 04 February 2019 - 10:06 PM

Hi Don,

 

Sorry but when you say "the late Nytecam", are you saying he passed away?  If so I had not heard that.  What a great loss to the EAA community.

 

Regards,

 

Jim T.

Yes, Jim, I am sad to report that Maurice Gavin, aka Nytecam, passed away on June 5, 2018.  He was an inspiration to many and was the one who got me into EAA with the Lodestar originally.  It was a great loss as you say, to EAA and amateur astronomy.  Here was a nice thread started by Nick as a tribute to him from the CN EAA community.

 

https://www.cloudyni...ce/?hl= nytecam

 

Don


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#34 will w

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Posted 04 February 2019 - 10:36 PM

Also Jim you mention that cmos sensors require stacking but did not the Mallincam extremes and Starlight Lodstars having ccd's use stacking software like Miloslick and Starlight Live to enhance their views?

 

Steve

Steve, Most software out has stacking and binning in it if you wont to use it. If you are doing video. No binning or stacking a CCD will put your object on your screen faster than a CMOS camera. But the CCD will not have the resolution that the CMOS camera will have.I dont know where most in this forun do video or semi AP with their cameras.From what pictures i see posted here with a CMOS and CCD cameras is a big time difference.When i do use my CCD xtreme with miloslick s/w. I dont stack. Miloslick does not have binning it it. At least i have not found it in the s/w. Now if i wont to do AP or semi AP i will stack. Then i can get a pretty picture like a CMOS camera. Read CharlesC post 26. will w



#35 alphatripleplus

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Posted 04 February 2019 - 10:38 PM

Just a couple of points - The ICX829 CCD sensor in the Lodestar X2 mono is very sensitive in my experience . As others have commented, with the larger pixels one gives up resolution with the Lodestar compared to newer smaller pixel CMOS sensors. In addition, given the higher read noise associated with a CCD compared to CMOS sensors, my typical sub-exposures are longer with the X2 compared to what I did when I owned a CMOS camera.

 

However, for a given total exposure, the only other sensor that is probably comparable in sensitivity is the IMX290 mono (based on comparisons I have seen posted by others, but not my first hand experience as I still have not got my hands on one). 

 

I routinely use Starlight Live to stack, and usually stack for longer than some others, as the SNR does continue to improve with more stacking, albeit more slowly as the stack length increases.

 

As this thread asks what can be seen in 30 seconds, here is an example of a single 30 second exposure of M52 and the Bubble Nebula (NGC7635) in H-alpha, taken @ f/4 with a ST80 and Lodestar X2 mono:

 

 

NGC7635, M52; 1 x 30sec (H-alpha)

 

NGC7635.M52.Ha_1x30s_ND_f4.0_RS_2017.11.13_21.55.48.jpg

 

 

 

 

For comparison, here is a longer stack of 45sec H-alpha subs taken a few minutes later the same evening with the same equipment:

 

NGC7635, M52; 16 x 45sec (H-alpha)

 

NGC7635.M52.Ha_16x45s_f4.0_RS_2017.11.13_22.28.43.jpg

 

 

The stacked exposure shows more extensive nebulosity around the Bubble, goes much deeper (more stars), and has a much smoother background -  a result of the improved SNR in the longer stack.... but I am still surprised that the Bubble can be captured in a single 30 sec H-alpha shot.


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#36 will w

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Posted 04 February 2019 - 10:55 PM

Errol, Thats a very good for 30 seconds. The 828 & 829 CCD chips are very sensitive. Rock uses them in some of his cameras. will w



#37 DSO_Viewer

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Posted 04 February 2019 - 10:57 PM

Steve, Most software out has stacking and binning in it if you wont to use it. If you are doing video. No binning or stacking a CCD will put your object on your screen faster than a CMOS camera. But the CCD will not have the resolution that the CMOS camera will have.I dont know where most in this forun do video or semi AP with their cameras.From what pictures i see posted here with a CMOS and CCD cameras is a big time difference.When i do use my CCD xtreme with miloslick s/w. I dont stack. Miloslick does not have binning it it. At least i have not found it in the s/w. Now if i wont to do AP or semi AP i will stack. Then i can get a pretty picture like a CMOS camera. Read CharlesC post 26. will w

I am confused here sorry Will but I have only been in this hobby for 2 years now and the term video that you use puzzles me. The only true camera that I have ever seen in true video mode was one from Japan that showed live 1/4 second exposures of deep sky objects that were not the brightest ones.  I have never seen a Mallincam extreme/exterminator or Lodstar ccd camera do this. If you have a link showing true video live 1/4 or less seconds on dso's, I would very much appreciate it.

 

Steve



#38 will w

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Posted 05 February 2019 - 09:38 AM

I am confused here sorry Will but I have only been in this hobby for 2 years now and the term video that you use puzzles me. The only true camera that I have ever seen in true video mode was one from Japan that showed live 1/4 second exposures of deep sky objects that were not the brightest ones.  I have never seen a Mallincam extreme/exterminator or Lodstar ccd camera do this. If you have a link showing true video live 1/4 or less seconds on dso's, I would very much appreciate it.

 

Steve

Steve, Try Wikipedia, www.wikipedia.org/   Type in video in the search box. that page will tell you what video is better than i can tell you. it will give you the history of video. will w



#39 jimthompson

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Posted 05 February 2019 - 09:40 AM

Yes, Jim, I am sad to report that Maurice Gavin, aka Nytecam, passed away on June 5, 2018.  He was an inspiration to many and was the one who got me into EAA with the Lodestar originally.  It was a great loss as you say, to EAA and amateur astronomy.  Here was a nice thread started by Nick as a tribute to him from the CN EAA community.

 

https://www.cloudyni...ce/?hl= nytecam

 

Don

frown.gif  Thanks for the information Don.  I had no idea.



#40 jimthompson

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Posted 05 February 2019 - 09:43 AM

I am confused here sorry Will but I have only been in this hobby for 2 years now and the term video that you use puzzles me. The only true camera that I have ever seen in true video mode was one from Japan that showed live 1/4 second exposures of deep sky objects that were not the brightest ones.  I have never seen a Mallincam extreme/exterminator or Lodstar ccd camera do this. If you have a link showing true video live 1/4 or less seconds on dso's, I would very much appreciate it.

 

Steve

Hi Steve,

 

I believe Will is talking about video astronomy from the perspective of using a camera who's output is analog video, what some may call "classical" EAA.  I don't think he was implying a camera that presents live images of deepsky objects at 30fps.

 

cheers,

 

Jim T.


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#41 DSO_Viewer

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Posted 05 February 2019 - 12:07 PM

Steve, Try Wikipedia, www.wikipedia.org/   Type in video in the search box. that page will tell you what video is better than i can tell you. it will give you the history of video. will w

Will, I do not always trust Wikipedia. I will go with what I have always knew video as which is 30 fps either both analog or digital.

 

Steve



#42 DSO_Viewer

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Posted 05 February 2019 - 12:08 PM

Hi Steve,

 

I believe Will is talking about video astronomy from the perspective of using a camera who's output is analog video, what some may call "classical" EAA.  I don't think he was implying a camera that presents live images of deepsky objects at 30fps.

 

cheers,

 

Jim T.

Okay Jim so are not Lodestar cameras digital using USB?

 

Steve



#43 will w

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Posted 05 February 2019 - 06:22 PM

Steve. My xtreme camera runs at 29 or 30 fps straight out . No stacking, No binning. I adjust other things in the s/w while the camera is runing. That is video to me. I am not trying to double my frames with stacking and binning. You can get a digital camcorder or a 8mm camcorder. They both do video. Nethier will have stacking or binning. Just video. Oh, you dont have belive every thing on wikipedia, but it does give you some insight on video with CCD and CMOS cameras.You can use your Iphone to make a video, But its all video.Any camera will only take one frame at a time reguardless of 30 fps or 40,000 fps. Any way CCD chips are faster than CMOS chips. will w



#44 Don Rudny

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Posted 05 February 2019 - 07:51 PM

Okay Jim so are not Lodestar cameras digital using USB?

 

Steve

Steve,

 

Even though the Mallicam and Lodestar use the same 828/829 sensor, they are different animals.  The Mallincams are true analogue video cams with 30fps (NTSC).  Mallincam and some security cams implement an integration of the shutter that gives extended exporsures at 30fps.  That why once you get at object say, at 17s and move to another, you can watch the previous one disappear and the new one slowly take its place.

 

The Lodestar uses the 829 chip as a digital output with an A to D converter.  It is not a video camera.  Each exposure is a single frame.  There is no slow merging of an image.  It becomes an image head camera needing a computer and program to generate the exposure and image.  The MC is totally self contained.  The Lodestar can’t do anything without a computer and software. 

 

Hope that helps to explain the difference.

 

Don


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#45 will w

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Posted 05 February 2019 - 08:47 PM

Don,The xterminator with the 828 chip has a A&D converter built in it. The xtremes have 418 & 428 chips no A&D converter. will w



#46 DSO_Viewer

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Posted 05 February 2019 - 10:48 PM

Steve. My xtreme camera runs at 29 or 30 fps straight out . No stacking, No binning. I adjust other things in the s/w while the camera is runing. That is video to me. I am not trying to double my frames with stacking and binning. You can get a digital camcorder or a 8mm camcorder. They both do video. Nethier will have stacking or binning. Just video. Oh, you dont have belive every thing on wikipedia, but it does give you some insight on video with CCD and CMOS cameras.You can use your Iphone to make a video, But its all video.Any camera will only take one frame at a time reguardless of 30 fps or 40,000 fps. Any way CCD chips are faster than CMOS chips. will w

Will do you have any deep sky object images using your extreme camera at 29 or 30 fps? If so, I would like to see them since as I said before the only camera that actually did true video was a Sony A7S that was captured from Japan.

 

Steve



#47 DSO_Viewer

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Posted 05 February 2019 - 10:54 PM

Steve,

 

Even though the Mallicam and Lodestar use the same 828/829 sensor, they are different animals.  The Mallincams are true analogue video cams with 30fps (NTSC).  Mallincam and some security cams implement an integration of the shutter that gives extended exporsures at 30fps.  That why once you get at object say, at 17s and move to another, you can watch the previous one disappear and the new one slowly take its place.

 

The Lodestar uses the 829 chip as a digital output with an A to D converter.  It is not a video camera.  Each exposure is a single frame.  There is no slow merging of an image.  It becomes an image head camera needing a computer and program to generate the exposure and image.  The MC is totally self contained.  The Lodestar can’t do anything without a computer and software. 

 

Hope that helps to explain the difference.

 

Don

Thank you Don for pointing out the difference between the two cameras. As  I mentioned I am new at this for only 2 years and I am confused when Will uses the term video for EAA in particular deep sky objects. I have never seen a single image posted here of a deep sky object using 1/4 seconds 29 or 30 fps. Can the Mallincam Extreme actually do this like Will says it can? I have only witnessed this watching a YouTube video from Japan using a Sony A7S. Thank you for any enlightenment.

 

Steve



#48 DSO_Viewer

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Posted 05 February 2019 - 10:58 PM

Don,The xterminator with the 828 chip has a A&D converter built in it. The xtremes have 418 & 428 chips no A&D converter. will w

Sorry Will I am confused again. How can the extreme use a ccd sensor and not have and A&D converter? I thought it goes from digital to analog back to digital. Thank you for any assistance.

 

Steve



#49 will w

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Posted 06 February 2019 - 11:57 AM

Steve, No i do not have any pictures of DSOs taken with my xtreme. I dont keep very many pictures. The xtreme is a analog camera it uses a analog to digital converter called a frame grabber.Digital cameras are mostly USB hook up cameras that needs a computer to show you what the camera is seeing.Analog cameras can use a computer and they can be hooked up to tv or monitor direct. Analog cameras have BNC and S VIDEO hook ups. We are more or less getting off topic from what the OP posted here.There are some posts about the sony A7S camera here. As for your 1/4 seconds 29 or 30 fps. I did not say my xtreme does that. Software is out that will go down onto milli seconds.You can go to the camera makers websites and read about their cameras. I read about other brands that i dont own. Dont forget about your S/W too.  will w



#50 DSO_Viewer

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Posted 06 February 2019 - 12:32 PM

Steve, No i do not have any pictures of DSOs taken with my xtreme. I dont keep very many pictures. The xtreme is a analog camera it uses a analog to digital converter called a frame grabber.Digital cameras are mostly USB hook up cameras that needs a computer to show you what the camera is seeing.Analog cameras can use a computer and they can be hooked up to tv or monitor direct. Analog cameras have BNC and S VIDEO hook ups. We are more or less getting off topic from what the OP posted here.There are some posts about the sony A7S camera here. As for your 1/4 seconds 29 or 30 fps. I did not say my xtreme does that. Software is out that will go down onto milli seconds.You can go to the camera makers websites and read about their cameras. I read about other brands that i dont own. Dont forget about your S/W too.  will w

Thank you Will and the information that you provided helped me out. I did not think that the Extreme camera could do deep sky as a single image in 1/4 second at 29 or 30 fps, if so I would be looking for one. These cameras were way before me time in EAA and I am quite sure that they were very good for their time.

 

Steve




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