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  #21  
Old 07-12-2014, 12:13 PM
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AstroJunk (Jonathan)
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Originally Posted by zenith View Post
I am not ready for Sony. My expensive Sony television died long before its time, and my mate's play station did not work out of the box. It took him hours on the phone, and 3 months in total to have it replaced (with him footing all shipping costs). I have a Sony DVD player and it has every feature know to mankind, and all of them are executed poorly, including the only ones I really need: stop, play, pause, top-menu.
They will need to lift their quality and customer service before I shop with them again.
Indeed, I own some rubbish Sony products as far a execution is concerned, hence Jobbsie getting back into the tech market with a certain iPod!! Although I still use a quite superb 1990's CRT Tv for video use
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  #22  
Old 07-12-2014, 02:50 PM
raymo
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Although at risk of hijacking the thread, I'd like to say that in my experience, Sony products, which used to be mid range, seem to have gone downhill in recent times. My daughter's large, heavy, and expensive TV has been lugged to the repair shop three times; each time to have the same component replaced, and my stereo packed up entirely at a young age.
raymo
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  #23  
Old 12-12-2014, 08:30 PM
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I was drawn like a moth the flame of the Sony alpha series and discovered a camera that was beginning to feel and act like something I would expect in an internet connected world, and was especially interested to discover that you can buy apps for it including star trails and time lapse software.

My dilemma though would be the choice between the A7R and A7S which are so different, and I just feel that the monster pixels of the A7S are a big price to pay for the increased sensitivity, on the other hand...[/QUOTE]

Sony is about to release a 50mp full frame pro E mount camera in Jan/Feb. Its supposed to be a challenge to the Pro DSLRs. Time will tell if its up to the job. I have an A7r and love it for its form and I quite like the Zeiss lenses. D800e is a bit of a smoother camera but harder to get the shot in my opinion. A7r can be complex or act like a point and shoot which I like.

See the video of the Northern Lights Mike Salway linked. That is shot with an A7s. Also I have seen some comparisons between high ISO video from Canon 5D111 Canon C100, GH4 and A7s and the A7s beats them all easily although colour may not be as good as the Canons. A7s is the class leader for low light. For daylight still very good but 12mp isn't going to show 36mp resolution.


Greg.
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  #24  
Old 03-02-2015, 10:54 AM
bwana (Brian)
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Originally Posted by gregbradley View Post
...
The interesting development to me in camera sensors is likely about to be released by Sony. An active pixel sensor that does not have a Bayer filter array, shoots in colour and somehow gets red, green and blue info of each pixel, has 24 stops of dynamic range at ISO5120 and low noise and capable of 16,000 frames per second. If all true it would be an unbelievable jump in sensor performance. I believe its not far away.

It potentially could be a huge advance for astrophotography. Low noise at high ISO being the unkown factor but likely to be good as the pixels can be very large due to not needing 4 pixels to make a colour pixel like in Bayer sensors.

Greg.
There was a research paper published about two years ago (from a university in Italy) regarding sensor technology that hinted that microchip technology had advanced to the state where it was feasible to have each photosite on a bare sensor determine the frequency/energy of the light being captured and output a color value & luminosity directly without the necessity of bayer filters or a lot of the current nonsense associated with capturing a color image...

Sounds a bit far fetched but when you think about it, it is probably quite doable if one can reduce what is essentially a spectrograph to the size of a photosite on a sensor.

I for one would love to test this sensor!

bwa
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  #25  
Old 03-02-2015, 11:35 AM
bwana (Brian)
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Originally Posted by AstroJunk View Post
...

My dilemma though would be the choice between the A7R and A7S which are so different, and I just feel that the monster pixels of the A7S are a big price to pay for the increased sensitivity, on the other hand...
The A7S and A7R are indeed different, in resolution as well as noise control. A repost I recently dropped to DPReview:

"Up to about ISO 1600 (maybe 3200) I think the image quality off the Sony A7R is better than the Sony A7S, being that image quality is a blend of both resolution and noise control. And yes, I realize this sort of shoots down my argument that nobody needs high MPixel cameras, at least for daytime shooting .

How I use the A7R and A7S is based very much on how they perform (noise-wise) under the available light. The A7R is pretty good up to about ISO 3200 (can be pushed to ISO 6400). The A7S excels at ISO 3200 up to about 51200. It is interesting that my quality cutoff on both cameras is 1/8th the maximum allowed ISO setting; by design??

I've done a bit of noise analysis on several Sony/Canon cameras using 30 sec Darks at about 20-22C and the Noise Evaluation utility in PixInsight.

My noise evaluation of the Sony A7 II shows it to be about the same as the A7R.

The Canon 6D has better noise control (about 33% better) than the Sony A7R/A7 all the way up to ISO 12800 (the highest I went). Its noise also increases slightly less with increased ISO than does the A7R/A7.

Testing the Canon 60D shows it's noise at ISO 3200 to be about the same as the 6D's at ISO 8000. I even tested my old Canon Rebel XTi. At ISO 1600 it is about a noisy as the 6D at ISO 6400.

I was also provided Darks off a Canon 7D II for testing but I think there was something wrong with the data provided because it tested twice as noisy as the Canon 6D which I find hard to believe? I would have expected it to be about equivalent to the 6D, maybe a touch worse, even considering it has an APS-C sensor and smaller photosites.

The Sony A7S had about 5x less noise than the A7R/A7 II all the way through its ISO range; about a two+ stop advantage." Of course you do gain some noise reduction by downsampling A7R images to A7S size but the A7S, in my opinion, still blows the wheels off the A7R/A7 II!

My testing also indicated the A7S had about 3x less noise than the Canon 6D in the ISO range tested: 3200-12800.

After reading a few reviews on the Canon 7D II, I'm no longer sure whether the Darks off the camera were good or faulty. I've seen reviews ranging from good to poor. Not sure where I stand on the latest edition of the 7D!? However, it really doesn't matter since I will never purchase another APS-C sensor camera after using full frame, and with the Sony A7 series cameras I can shoot in crop mode and still retain the noise advantage of a full frame sensor; win, win!!

Just my ramblings (from Canada)...

bwa

The large number of the images in the following albums were shot with my A7R and/or A7S (both cameras full spectrum modded):
Misty Valley Ranch Albums
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  #26  
Old 03-02-2015, 02:08 PM
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Originally Posted by bwana View Post
There was a research paper published about two years ago (from a university in Italy) regarding sensor technology that hinted that microchip technology had advanced to the state where it was feasible to have each photosite on a bare sensor determine the frequency/energy of the light being captured and output a color value & luminosity directly without the necessity of bayer filters or a lot of the current nonsense associated with capturing a color image...

Sounds a bit far fetched but when you think about it, it is probably quite doable if one can reduce what is essentially a spectrograph to the size of a photosite on a sensor.

I for one would love to test this sensor!

bwa
Wow, imagine that!

Sony has patented a sensor where the colour filter array moves with each shot creating the RGB for each pixel.

Rumour is they are also working on a sensor similar to the Foveon sensor which differentiates between RGB by the depth in the silicone the signal reaches. RGB are read at different depths in the silicone. The problem is Foveon sensors whilst incredibly high res are very poor at higher ISOs.

Greg.
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  #27  
Old 03-02-2015, 02:27 PM
PeterEde (Peter)
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no flipout display. Not for me
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  #28  
Old 03-02-2015, 04:25 PM
bwana (Brian)
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Originally Posted by gregbradley View Post
Wow, imagine that!

Sony has patented a sensor where the colour filter array moves with each shot creating the RGB for each pixel.

Rumour is they are also working on a sensor similar to the Foveon sensor which differentiates between RGB by the depth in the silicone the signal reaches. RGB are read at different depths in the silicone. The problem is Foveon sensors whilst incredibly high res are very poor at higher ISOs.

Greg.
I wonder what the speed of a moving filter array exposure might be? Sounds like there could be time for movement between the capture of the R, G & B channels, i.e.: motion smear?

As for Sigma's Foveon, if the problem of poor sensitivity at higher ISO's could be resolved, it might have potential. However, in a recent interview Shri Ramaswami w/ Foveon stated, "And of course, there are some disadvantages with our approach. Everyone knows our high ISO, for instance, isn't up to the standards of the competition." And he didn't suggest Sigma/Foveon had any remedy for the problem . In fact it may be physics controlling the process which means it is as good as it gets!?

Interesting article at: http://www.mirrorlessrumors.com/new-...-has-36-layers but a long, long way from market!

Gotta love the technological advances (and sometimes the retreats) in the field of photography...

bwa
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  #29  
Old 03-02-2015, 04:26 PM
bwana (Brian)
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no flipout display. Not for me
Yes, that LiveView screen on the 60D is wonderful!

bwa
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  #30  
Old 03-02-2015, 10:11 PM
ericwbenson (Eric)
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There already is a motion "blur"! Check out the attached image I took in 2011 with an EOS 350D + Canon 70-200 f/4 IS (what a *great* lens) and compare the shadow to the real scene (which are separated by about 2 m = 20 nsec).
I think I know what the mechanism behind this is, but I'm not 100% sure

I had not noticed for 3 years until coincidentally the kids where looking thru Picassa today and my wife noticed this very interesting difference. I've been to the Aussie Open twice since and have never managed to replicate the squashed tennis ball, beginner's luck?...maybe next year.

EB
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  #31  
Old 03-02-2015, 10:32 PM
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There already is a motion "blur"! Check out the attached image I took in 2011 with an EOS 350D + Canon 70-200 f/4 IS (what a *great* lens) and compare the shadow to the real scene (which are separated by about 2 m = 20 nsec).
I think I know what the mechanism behind this is, but I'm not 100% sure

I had not noticed for 3 years until coincidentally the kids where looking thru Picassa today and my wife noticed this very interesting difference. I've been to the Aussie Open twice since and have never managed to replicate the squashed tennis ball, beginner's luck?...maybe next year.

EB
That's a great shot! It really underscores the scanning nature of electronic chips
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  #32  
Old 04-02-2015, 05:02 AM
SteveInNZ
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That's a great shot! It really underscores the scanning nature of electronic chips
No, it shows the scanning nature of the focal plane shutter.

Steve.
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  #33  
Old 04-02-2015, 06:36 AM
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That's right.

The shutters have a horizontal slit which varies in width depending on the speed of the shutter.

It goes from top of the sensor down to the bottom. Keep in mind the image is upside down from the lens. So the top of the image here is the bottom of the final picture. That got exposed first and as the shutter moves down the sensor it exposes as it goes. So that means the guy hitting the ball got exposed later than the shadow and he was moving fast so it was a tad later in time. Its called rolling shutter effect.

A development expected of DSLRs in the future is a global shutter where the whole sensor is read out at the same time.

Greg.
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