SONY ALPH A A750

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Greg Beetham
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Re: SONY ALPH A A750

Unread post by Greg Beetham »

I was sortof kicking the splitter prizm with two sensors idea around 'loosely', maybe split 60/40 (light transmission) or even 70/30, with the 30 taking care of AF, EVF, metering, and the 70 doing LV and Video, the two sensors being of different size and gain etc. I thought that might be a possible answer to getting rid of the OVF and mirror... :roll:
David, can you nullify this as an option please, (it's ok if you completely kybosh it, nuke it from orbit, whatever), so I can continue thinking of the possibility of an advanced 'conventional' DSLR in the pipeline at some point..
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bossel
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Re: SONY ALPH A A750

Unread post by bossel »

hey come on, it's just a rumour. They might even remove the shutter button and make everything voice controlled (but that's just a rumour, too ) :mrgreen: I don't believe in any solution that would take away half a stop of light or more.
Tony Meredith
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Re: SONY ALPH A A750

Unread post by Tony Meredith »

Perhaps Sony has been able to develop a special coating on the pellicle mirror that changes reflectivity when a small electrical charge is applied to it, a bit like an auto darkening welding screen.
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Re: SONY ALPH A A750

Unread post by Winedarksea »

It's very hard for me to understand how anyone would forego the most fts possible, short of compromising the camera and breaking the bank. Just watch what happens when you photograph someone talking at even 5 fps, especially someone with an expressive face! Wow! We have been missing so much all these years without high fps.

And DK, thanks so much for your lucid explanation of the alternatives that Sony might be looking at, if yesterday's "rumor" is based on anything at all. The described camera, whatever it might be, certainly would fit Gustav's description of the A7xx as a camera that the camera world will be talking about for a long time.

Makes me very nervous, but excited at the same time. I'm thinking more and more that at least one of the new cameras will be announced pretty darned soon. CES, anyone?
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Winedarksea
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Re: SONY ALPH A A750

Unread post by Winedarksea »

bossel wrote:hey come on, it's just a rumour. They might even remove the shutter button and make everything voice controlled (but that's just a rumour, too ) :mrgreen: I don't believe in any solution that would take away half a stop of light or more.
Well, I woulld agree, but that was with 30- or 40-year-old technology. Maybe Sony has found a way around that.

I suspect that this rumor may well have been supplied by Gustav, so I wouldn't bet too much against it.

Dulaney
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kingfisher
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Re: SONY ALPH A A750

Unread post by kingfisher »

i did not supplied this rumor


http://sonyalpharumors.com/sony-alpha-7 ... ws-coming/

i only find this on the internet

gustav
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Re: SONY ALPH A A750

Unread post by Winedarksea »

kingfisher wrote:i did not supplied this rumor


http://sonyalpharumors.com/sony-alpha-7 ... ws-coming/

i only find this on the internet

gustav
'

OK, my bad, I was going on the basis that your nick on Dyxum is IJsvogel, and that SAR said the source of the rumor was JV from the Netherlands. Thanks for the clarification, and sorry for making you uncomfortable if I did.

What is your take on the rumor?

Dulaney
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prjohn
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Re: SONY ALPH A A750

Unread post by prjohn »

bossel wrote: They might even remove the shutter button and make everything voice controlled
I don't think so!

Sony's new camera will not need voice control. It will hover beside you at all times and because of it's super intelligent microprocessor it will always detect and take the perfect photo. Due to built in wireless the photo will be sent to your home printed and framed. A image will also be sent to a sock image library where because of the image quality you money will be made instantly.

The photo will also be signed "Sony"
The world is your playground, why don't you play?

Sony A500, Sony 16-105mm, Minolta 70-210mm f4, Tair 300mm f4.5, Pentacon 50mm f1.8. Carl Zeiss jena 135mm f3.5.
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kingfisher
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Re: SONY ALPH A A750

Unread post by kingfisher »

hi dulaney

i shall try to give a answer
there are two thinks , what i now , and what i think

first what i now

not so lang ago they told me ( they is someone from sony ) that next year there come a new A700
and he say literally it is a camera where hole camera-world shall talking about
also he said , that next year come`s a lot of lenses , i think around ten

what i think

a very fast camera
14MP and maybe a 16MP
APS-C
live-view
penta-prisma ore something else but no penta mirror

launched around march april

i read something interesting on a dutch forum about this rumor of a pellicle mirror :

There has been a lot of fuss lately on a rumour that the successor of the A700 will have a fixed mirror to enable video and a fast frame rate. Most of this revolves around the statement that this is old technology as used over 10 years ago in the Canon Eos 1V and it means a 1/3 of a stop or more loss in light falling on the sensor because the mirror continuously sits in the way of the light coming in. The new mirror is apparently based on a patent that was filed by Minolta some years ago.

I have not taken the trouble to search for the patent, but what if this mirror is based on the possible concept that the reflective properties can be adjusted at will by means of an electrical current so it can be switched on and off in a split second. This enables live view, video, high frame rates, no or very limited loss of light intensity and most important to me, much reduced vibrations as the mirror is not flipping up and down anymore. Also the cost of the mirror box assembly is potentially much lower. This basically generates a rangefinder with TTL view. Of course there is another layer between the lens and the sensor but if the IR-cut filter and other coatings are moved from the sensor to the mirror surface this might be much less of a problem. Also dust particles no longer settle on the sensor but on the mirror where they are way out of focus.

greetings
gustav
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Re: SONY ALPH A A750

Unread post by stevecim »

kingfisher wrote:hi dulaney


i read something interesting on a dutch forum about this rumor of a pellicle mirror :

I have not taken the trouble to search for the patent, but what if this mirror is based on the possible concept that the reflective properties can be adjusted at will by means of an electrical current so it can be switched on and off in a split second. This enables live view, video, high frame rates, no or very limited loss of light intensity and most important to me, much reduced vibrations as the mirror is not flipping up and down anymore. Also the cost of the mirror box assembly is potentially much lower. This basically generates a rangefinder with TTL view. Of course there is another layer between the lens and the sensor but if the IR-cut filter and other coatings are moved from the sensor to the mirror surface this might be much less of a problem. Also dust particles no longer settle on the sensor but on the mirror where they are way out of focus.

greetings
gustav
I had been thinking about this 12 months ago, did a little bit of research, around using a LCD shutter to form a mirror that can be switched on and off.
Sony will have to come up with a very improved type of LCD shutter,

The only thing that seemed suitable was (FOS-PSCT): Polymer Stabilised Cholesteric Textured (PSCT) liquid crystal shutter , this allows >88% of light to pass in "open" state, but only has switching speed around 0.5 ms which maybe to slow and needs +100V to activate, bit difficult from a 7.2 V battery ;). Would be interesting if Sony did come up with a switch-able mirror
alexramos7
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Re: SONY ALPH A A750

Unread post by alexramos7 »

David Kilpatrick wrote:
A final possibility is that the camera has no OVF, and the pellicle mirror serves only to feed an AF phase detect sensor array. Since it would be a full sized mirror, the AF array could be much larger ad cover the entire frame - even more points, and wider spread, than the Nikon MultiCam 3500. The sensor would feed an EVF of very high quality placed as for a normal prism eyepiece, so the camera would look much like a regular DSLR. The beamsplitter mirror could remain in place for video with continuous AF, and for action still shooting with the same - OR it could flip like a regular mirror, out of the way, for one-shot AF with zero loss of light to the sensor and zero loss of image quality (no mirror to pass through).

This last solution would be how I would design such a DSLR if an EVF was felt acceptable to replace OVF entirely.

Anyway, the mention of pellicle mirror has got people thinking Canon EOS RTS style - mirror used for OVF - without considering other ways in which a pellicle mirror could be used, such as this last option which solves the video AF problem.

Finally, there is no reason why a dual mirror assembly could not be used, with a regular SLR/secondary AF system for still shooting which rises and locks under the focus screen (as normal) when video shooting. This leaves room for separate hinged pellicle mirror to move into place feeding the AF sensor only, and covering the entire sensor field. In this mode video with phase detect AF would be possible, but the normal DSLR operation would remain unaffected.

David
So many time ago I though about this, a EVIL system with a Pellicle Mirror and Phase detection AF and LV.
It allow to use phase detection and contrast AF freely or combining them.
I make a scheme about it...

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