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Various DSO's unprocessed from Sony A7S

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#1 jdbastro

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Posted 29 July 2014 - 02:10 AM

Snapped a variety of DSO targets the other night from Mount Pinos, Calif. with the A7S and various lenses. Longest exposures were 30 sec (tracked). Shortest were 1 sec (untracked). All are Jpegs straight out of the camera with all default noise reduction enabled, white balance set to 3500K, 'clear' picture mode.

Here's the album link.

#2 nytecam

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Posted 29 July 2014 - 06:48 AM

Very nice wide angle results - what optics with the camera's large chip are needed for close-up of DSOs? TIA

#3 RandyC

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Posted 29 July 2014 - 08:37 AM

Snapped a variety of DSO targets the other night from Mount Pinos, Calif. with the A7S and various lenses. Longest exposures were 30 sec (tracked). Shortest were 1 sec (untracked). All are Jpegs straight out of the camera with all default noise reduction enabled, white balance set to 3500K, 'clear' picture mode.

Here's the album link.


Those are great you guys. DSOs must get really good at 60 seconds.

#4 Chris A

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Posted 29 July 2014 - 10:06 AM

Since this is a full size sensor capable of APS-C crop you would need a decent size aperture scope that has well corrected optics in order to see objects at higher details. I would say that a 10" or larger RC scope or C11 or larger HD Edge would do very well with this camera.

Chris A

#5 Chris A

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Posted 29 July 2014 - 10:11 AM

Very nice collection of images captured with your non modified Sony A7S. You can now see the effects of the non modified with the dominant of blue esp. on M76, Western Veil and M33 with no HII regions showing. This camera does seem to be extremely sensitive and would make a great electronic observing device of course modified with the proper filter.

Chris A

#6 mpgxsvcd

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Posted 29 July 2014 - 01:56 PM

That thing is a beast! A very nice camera that is.

#7 Moromete

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Posted 29 July 2014 - 03:43 PM

Snapped a variety of DSO targets the other night from Mount Pinos, Calif. with the A7S and various lenses. Longest exposures were 30 sec (tracked). Shortest were 1 sec (untracked). All are Jpegs straight out of the camera with all default noise reduction enabled, white balance set to 3500K, 'clear' picture mode.

Here's the album link.


Nice shots!

One question: why does your NGC 6960 image does not have any red color compared to same image taken by bwallan here https://plus.google....148685511342... , considering both images were taken with unmodified A7S?

#8 jdbastro

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Posted 29 July 2014 - 05:04 PM

Snapped a variety of DSO targets the other night from Mount Pinos, Calif. with the A7S and various lenses. Longest exposures were 30 sec (tracked). Shortest were 1 sec (untracked). All are Jpegs straight out of the camera with all default noise reduction enabled, white balance set to 3500K, 'clear' picture mode.

Here's the album link.


Nice shots!

One question: why does your NGC 6960 image does not have any red color compared to same image taken by bwallan here https://plus.google....148685511342... , considering both images were taken with unmodified A7S?


Thanks.

I think it's because bwallan's shots are the results of several stacked images subsequently 'tweaked' a bit via post-processing.

My shots are all single takes straight out of the camera with no post-processing at all. If you look real closely at my Western Veil, there is a hint of red. I imagine several stacked images might help bring out the red, but that's just a guess.

Also, the color temp used in my shots (3500K) may have been dialed in a bit too cool to capture red. On my next outing I can try to warm it up a bit (closer to 5500K). Or maybe I could wise up and start shooting RAW some day.

#9 jdbastro

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Posted 29 August 2014 - 01:30 AM

Just thought I'd highlight some additional unprocessed, straight-from-the-camera, single exposure DSO shots taken with my Sony A7S and several telescopes from Mount Pinos, Calif, this past weekend:

 

Here are some of my favorites:

 

M27:

M27_Mewlon250_30sec_20000iso_zps66f33ac5

Mewlon 250 @ f9.2, Sony A7S, 30 sec, 20,000 ISO, APSC crop

 

 

M57:

RingNeb_Mewlon250_30sec_20000iso_zps8c53

Mewlon 250, @ f12, Sony A7S, 30 sec, 20,000 ISO, APSC Crop

 

M16:

M16_Mewlon250_30sec_25600iso_zps6556e7b2

Mewlon 250 @ f9.2, Sony A7S, 30 sec, 25,600 ISO, APSC Crop

 

Trifid Nebula:

TrifidNeb_Mewlon250_30sec_20000iso_zps8e

Mewlon 250 @ f9.2, Sony A7S, 30 sec, 20,000 ISO, APSC crop

 

Lagoon Nebula:

LagoonNeb_Mewlon250_30sec_20000iso_zps5f

Mewlon 250 @ f9.2, Sony A7S, 30 sec, 20,000 ISO, APSC crop

 

Lagoon & Trifid

Lagoon_Trifid_Nebs_Sky90_30sec_4000iso_z

Sky 90 @ f4.5, Sony A7S, 30 sec, 4,000 ISO, APSC Crop

 

M17 & M16:

M17_M16_Sky90_30sec_5000iso_FullFrame_zp

Sky 90 @ f4.5, Sony A7S, 30 sec, 5,000 ISO, APSC crop

 

N American Nebula:

NAmericanNeb_Zeiss200f2_20sec_3200iso_zp

Zeiss ApoSonnar 200mm/f2 @ f2, Sony A7S, 20 sec, 3,200 ISO, APSC crop

 

There are a few more pics at this Link.



#10 chasing photons

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Posted 29 August 2014 - 08:29 AM



These are beautiful EAA images and a nice stills gallery! This is the closest to what I have been waiting for in results from a near real time observing system. May I ask what your current setup is for shooting stills as far as controlling the camera and seeing the ‘live view’ of the exposure? Do you use a remote APP on a tablet or phone to control the settings and see the images? You mentioned elsewhere that you like to use video mode at 4fps and high ISOs to center the DSOs. Is it easy to switch back and forth between video and stills modes, or do you even have access to the video mode when shooting stills? Thank you so much for sharing!

#11 RandyC

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Posted 29 August 2014 - 10:28 AM

Those are great, You can see the blue is because the camera is unmodded. There are several aftermarket places that will remove the UV/IR filter on the A7S. I asked BHPhoto once and they said it can't be done...but it can. Also using a bulb you can go to a minute or so and step down the ISO. Great stuff!



#12 dtripz

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Posted 29 August 2014 - 12:18 PM

These are great shots but I hope you continue posting those awesome IIE shots for everyone.

#13 Traian

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Posted 05 September 2014 - 01:45 AM

Just thought I'd highlight some additional unprocessed, straight-from-the-camera, single exposure DSO shots taken with my Sony A7S and several telescopes from Mount Pinos, Calif, this past weekend:

 

Here are some of my favorites:

 

M27:

M27_Mewlon250_30sec_20000iso_zps66f33ac5

Mewlon 250 @ f9.2, Sony A7S, 30 sec, 20,000 ISO, APSC crop

 

 

M57:

RingNeb_Mewlon250_30sec_20000iso_zps8c53

Mewlon 250, @ f12, Sony A7S, 30 sec, 20,000 ISO, APSC Crop

 

M16:

M16_Mewlon250_30sec_25600iso_zps6556e7b2

Mewlon 250 @ f9.2, Sony A7S, 30 sec, 25,600 ISO, APSC Crop

 

Trifid Nebula:

TrifidNeb_Mewlon250_30sec_20000iso_zps8e

Mewlon 250 @ f9.2, Sony A7S, 30 sec, 20,000 ISO, APSC crop

 

Lagoon Nebula:

LagoonNeb_Mewlon250_30sec_20000iso_zps5f

Mewlon 250 @ f9.2, Sony A7S, 30 sec, 20,000 ISO, APSC crop

 

Lagoon & Trifid

Lagoon_Trifid_Nebs_Sky90_30sec_4000iso_z

Sky 90 @ f4.5, Sony A7S, 30 sec, 4,000 ISO, APSC Crop

 

M17 & M16:

M17_M16_Sky90_30sec_5000iso_FullFrame_zp

Sky 90 @ f4.5, Sony A7S, 30 sec, 5,000 ISO, APSC crop

 

N American Nebula:

NAmericanNeb_Zeiss200f2_20sec_3200iso_zp

Zeiss ApoSonnar 200mm/f2 @ f2, Sony A7S, 20 sec, 3,200 ISO, APSC crop

 

There are a few more pics at this Link.

 

Exceptional images for ISO 20.000 and non-processed single exposures!

 

 

 

Looking at those fine images a few questions arise in my mind:

 

1) are the Lagoon and Triffid images taken (at ISO20.000)  with NR on Normal and in-camera Dark Frame Subsctraction on On?

 

2) have you noticed any artifacts/problems with A7S RAW images because they are lossy compressed and 12Bit when processing and looking at them at 1:1 on screen?

 

3) is Lightroom able to handle the Sony A7S smaller RAWs taken in APS-C mode?

 

4) is DeepSkyStacker able to handle the Sony A7S smaller RAWs taken in APS-C mode?

 

5) are the nice images you posted JPEGs or RAWs?

 

 

 

Thank you.



#14 Dom543

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Posted 05 September 2014 - 08:47 AM

This is really a very sensitive camera and images are very nice. But they are monochrome blue. Just as IIE is green, Sony is blue.
The question is, can the color balance set so that it also lets reds to be displayed? Or is there a physical filter inside that cuts out Ha plain and simple?

--Dom

#15 Chris A

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Posted 05 September 2014 - 06:41 PM

This is really a very sensitive camera and images are very nice. But they are monochrome blue. Just as IIE is green, Sony is blue.
The question is, can the color balance set so that it also lets reds to be displayed? Or is there a physical filter inside that cuts out Ha plain and simple?

--Dom

Dom the reason for the strong blue and weak red is because of the stock filter that Sony and all other camera brand use to block IR in order to have a proper color balance for terrestrial objects.

 

Chris A



#16 jdbastro

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Posted 06 September 2014 - 12:17 AM

 


Exceptional images for ISO 20.000 and non-processed single exposures!

 

 

Looking at those fine images a few questions arise in my mind:

 

1) are the Lagoon and Triffid images taken (at ISO20.000)  with NR on Normal and in-camera Dark Frame Subsctraction on On?

 

2) have you noticed any artifacts/problems with A7S RAW images because they are lossy compressed and 12Bit when processing and looking at them at 1:1 on screen?

 

3) is Lightroom able to handle the Sony A7S smaller RAWs taken in APS-C mode?

 

4) is DeepSkyStacker able to handle the Sony A7S smaller RAWs taken in APS-C mode?

 

5) are the nice images you posted JPEGs or RAWs?

 

 

 

Thank you.

 

Thanks for looking.  Answers to your questions:

 

1) Yes.  Actually all of these images are taken with NR on normal and dark frame subtraction.

2) I haven't done any RAW shooing yet with my A7S.  Can't answer this one.

3) Don't know.  Probably.  Try using google on this.  If not, Sony has a free s/w package called: Image Data Converter.

4) Also don't know.

5) I'm a JPEG guy.  All images are JPEGS straight off the camera with a simple down size via irfanview.



#17 Relativist

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Posted 06 September 2014 - 12:43 AM

Of all of those, personally, I'd suggest looking into DSS compatibility. There are a couple of live view associated tools for DSS, DSS live, and the DSS Observer toolbar.  The author of the DSS Observer toolbar has asked for files to test if someone is willing to provide them.



#18 Moromete

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Posted 06 September 2014 - 02:50 AM

 

 


Exceptional images for ISO 20.000 and non-processed single exposures!

 

 

Looking at those fine images a few questions arise in my mind:

 

1) are the Lagoon and Triffid images taken (at ISO20.000)  with NR on Normal and in-camera Dark Frame Subsctraction on On?

 

2) have you noticed any artifacts/problems with A7S RAW images because they are lossy compressed and 12Bit when processing and looking at them at 1:1 on screen?

 

3) is Lightroom able to handle the Sony A7S smaller RAWs taken in APS-C mode?

 

4) is DeepSkyStacker able to handle the Sony A7S smaller RAWs taken in APS-C mode?

 

5) are the nice images you posted JPEGs or RAWs?

 

 

 

Thank you.

 

Thanks for looking.  Answers to your questions:

 

1) Yes.  Actually all of these images are taken with NR on normal and dark frame subtraction.

2) I haven't done any RAW shooing yet with my A7S.  Can't answer this one.

3) Don't know.  Probably.  Try using google on this.  If not, Sony has a free s/w package called: Image Data Converter.

4) Also don't know.

5) I'm a JPEG guy.  All images are JPEGS straight off the camera with a simple down size via irfanview.

 

 

May I give you a piece of advice to fully exploit the fantastic quality of your single shots taken with A7S?

 

If yes, please put NR on LOW next time because you should obtain even better looking single shots with A7S. Sony's NR in A7 series is too strong when on Normal and creates posterization.



#19 Dom543

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Posted 06 September 2014 - 10:34 AM

[/quote]
Dom the reason for the strong blue and weak red is because of the stock filter that Sony and all other camera brand use to block IR in order to have a proper color balance for terrestrial objects.
Chris A
[/quote]

Chris, Thank you for your reply.

I am aware of the fact that the spectral sensitivity curve of an electronic sensor is different from that of the human eye. In most consumer cameras a glass filter is used to tone down the long wavelength side of the curve and that way to achieve a color balance similar to how the human eye perceives terrestrial colors.

But this spectral sensitivity adjustment can also be achieved as part of the internal signal processing of the camera. In fact, if one uses a full-spectrum modified DSLR camera for daytime photography, one can use a custom white balance to achieve exactly this.

Spelled out more clearly, my original question was, if the Sony A7s uses a glass filter for spectral sensitivity adjustment or if it achieves this through internal signal processing. For such a sophisticated camera the DSP option is not an outlandish possibility. And if it is the case, then a custom white balance could be used to shift the sensitivity curve back to the native sensitivity of the sensor.

--Dom

#20 chasing photons

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Posted 06 September 2014 - 01:30 PM

...my original question was, if the Sony A7s uses a glass filter for spectral sensitivity adjustment or if it achieves this through internal signal processing. For such a sophisticated camera the DSP option is not an outlandish possibility. And if it is the case, then a custom white balance could be used to shift the sensitivity curve back to the native sensitivity of the sensor.

--Dom

 

 

This video clip shows a modified Sony A7S video at ~ 4fps (1/4 second integration) with significant signal at the red end of the spectrum in the DSOs…

 

http://www.youtube.c...h?v=UUzLJ-M2Z_I



#21 Chris A

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Posted 06 September 2014 - 02:08 PM

[/quote]
Dom the reason for the strong blue and weak red is because of the stock filter that Sony and all other camera brand use to block IR in order to have a proper color balance for terrestrial objects.
Chris A
[/quote]

Chris, Thank you for your reply.

I am aware of the fact that the spectral sensitivity curve of an electronic sensor is different from that of the human eye. In most consumer cameras a glass filter is used to tone down the long wavelength side of the curve and that way to achieve a color balance similar to how the human eye perceives terrestrial colors.

But this spectral sensitivity adjustment can also be achieved as part of the internal signal processing of the camera. In fact, if one uses a full-spectrum modified DSLR camera for daytime photography, one can use a custom white balance to achieve exactly this.

Spelled out more clearly, my original question was, if the Sony A7s uses a glass filter for spectral sensitivity adjustment or if it achieves this through internal signal processing. For such a sophisticated camera the DSP option is not an outlandish possibility. And if it is the case, then a custom white balance could be used to shift the sensitivity curve back to the native sensitivity of the sensor.

--Dom

Dom nothing internally in the A7S will bring out the infrared spectrum if it is not allowed to fully enter to the sensor. This spectrum is being blocked out way too much with the stock filter and the exposures would need to be so much longer and even then the sensitivity in red will never equal to a modified A7S. 

 

Chris



#22 Relativist

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Posted 06 September 2014 - 02:09 PM

I agree, the videos of the modified A7s imply there is a physical UV/IR filter that should be removed for optimal astro use.



#23 Chris A

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Posted 06 September 2014 - 02:10 PM

I agree, the videos of the modified A7s imply there is a physical UV/IR filter that should be removed for optimal astro use.

You are 100% correct Curtis. This camera would be best modified for DSO's esp. for emission nebulas.

 

Chris



#24 Hunlon

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Posted 13 September 2014 - 10:36 PM

Nice work jbastro.  I look forward to more images - especially after they have been stacked and processed.

 

These single shot images show great promise.  I am inclined to believe that the white balance is responsible for the blue cast in your images.  Have you tried with different settings?  

 

Also have you tried higher ISOs?

 

The thought of being able to stack a hundred images at ISO 64000 makes me salivate.

 

Clear skies,

Hunlon.



#25 RandyC

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Posted 14 September 2014 - 12:04 AM

Nice work jbastro.  I look forward to more images - especially after they have been stacked and processed.

 

These single shot images show great promise.  I am inclined to believe that the white balance is responsible for the blue cast in your images.  Have you tried with different settings?  

 

Also have you tried higher ISOs?

 

The thought of being able to stack a hundred images at ISO 64000 makes me salivate.

 

Clear skies,

Hunlon.

I don't think you will need a hundred images at ISO64000. 60-90seconds at ISO 3200-6400 should do wonders. Nice and simple.








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