Quote:
Originally Posted by ozstockman
It is actually $2799 pre-order from Sony website and you can get it as a grey import from HK for less than $2300 plus shipping.
I am thinking of getting one for video astronomy but do not expect any reviews from me soon. I have not done any astro imaging for almost four years but want to go back as I love this hobby.
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Following his first light with the camera here's what Brian (a Canadian I know) had to say a couple of hours ago. I doubt he'd mind me passing it on.:
Quote:
I set up the Sony A7S between 2:30 & 3:00am this morning for some testing at various ISO's. Sky conditions were pretty much totally clouded over except for a (sorta) clear western horizon. The only light in the field-of-view was a single LED nightlight in our greenhouse. Two computer monitors were on in my office (behind and to the right of the camera and facing away from the windows) and the only thing illuminating the yard.
The album below shows the testing results:
https://plus.google.com/photos/11626...37165630549937
The image tests were:
2 sec. exposures at:
ISO 200
ISO 1600
ISO 6400 About what I could see with the naked eye.
ISO 12800
ISO 25600
ISO 51200
ISO 102400
ISO 204800
ISO 409600
ISO 409600 - Stacked of three of the above MFNR images
The ISO 6400 image shows about what I could see with my dark adapted eye!
20 sec. exposures at:
ISO 12800
ISO 25600
ISO 51200
ISO 102400
ISO 204800
ISO 409600 test was totally blown out and not included
All images were captured using the A7S's internal Multi Frame Noise Reduction (MFNR), essentially four images aligned and stacked. All other noise reduction was turned OFF.
The video tests were:
Full Frame, 1/4 sec. exposure:
ISO 25600 (658 frames)
ISO 51200 (943)
Crop Mode, 1/4 sec. exposure:
ISO 51200 (928)
ISO 102400 (928)
ISO 204800 (943)
ISO 409600 (3643)
ISO 409600 single frame from above video to show image quality prior to stacking; really crappy!
Crop Mode, 1/30 sec. exposure:
ISO 409600 (1828)
All video was captured in MP4 (1440x1080) format at 30fps. This is the worst video quality output by the A7S; therefore, capturing production video in AVCHD or XAVC S format should yield considerably better video/image quality.
All video footage was converted to uncompressed AVI format and stacked using RegiStax.
A few more details in the comments to the album
Now all I need is a night without total DENSE cloud to give the camera a real test...
Enjoy!
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