A7 crippled sensor?

For discussion of the E and FE mount mirrorless system
User avatar
bfitzgerald
Subsuming Vortex of Brilliance
Posts: 3689
Joined: Fri Sep 26, 2008 10:48 pm

A7 crippled sensor?

Unread postby bfitzgerald » Sun Oct 20, 2013 11:56 am

Well this one is a huge bomb if true. But it's been suggested on SAR that the A7 does not have offset micro lenses, but the A7r does.

That being the case the A7 is going to have lousy edge/corner performance with M mount lenses or native ones. If that is true Sony have made one massive deal killer mistake.
http://www.ronscheffler.com/techtalk/?p=224

He has samples to download

So right now I think Sony have made a major blunder here. So big in fact it could kill normal A7 sales and I can see people returning the camera. This probably also explains why Sony have no native UWA lens to release (zoom or prime) but even if they do the A7 is going to effectively be "sensor crippled" by not having offset micro lenses. Heads might roll on this one

User avatar
bakubo
Subsuming Vortex of Brilliance
Posts: 5697
Joined: Tue Nov 06, 2007 7:55 am
Location: Japan
Contact:

Re: A7 crippled sensor?

Unread postby bakubo » Tue Oct 22, 2013 12:33 pm

Sony probably makes a lot more money selling lenses than the A7 so I can see how they might intentionally design it to not work so well with old RF lenses. How about the A7r? I suppose that old SLR lenses would work okay on the A7, but they are larger and the adaptor is bigger.

For the people who have very expensive Leica lenses they probably won't mind at all having to spend a few hundred dollars more for the A7r. Pocket change.

User avatar
pakodominguez
Minister with Portfolio
Posts: 2544
Joined: Tue May 22, 2007 5:38 pm
Location: NYC
Contact:

Re: A7 crippled sensor?

Unread postby pakodominguez » Tue Oct 22, 2013 1:33 pm

bakubo wrote:Sony probably makes a lot more money selling lenses than the A7 so I can see how they might intentionally design it to not work so well with old RF lenses.

What lenses?
Lenses are Sony's weakness!
There are 2 different sensors, probably the 36MP is a new generation(the 24MP could be "the same" as the one on the A99/RX1) and that's why the different toppings. I don't understand why this information, that is public since the beginning, is now a "bomb".
In other hand, as you said, if you have a battery of Leica lenses, you can easily afford the A7R...
Pako
------------
http://www.pakodominguez.photo/blog" onclick="window.open(this.href);return false;

peterottaway
Imperial Ambassador
Posts: 601
Joined: Wed Nov 12, 2008 9:24 am
Location: Northam, Western Australia

Re: A7 crippled sensor?

Unread postby peterottaway » Tue Oct 22, 2013 4:21 pm

I can't see that it is Sonys responsibility to ensure that the A7 works with someones Leica or Cosina RF lenses. It may earn them an extra 10 sales here and 20 sales there but that would be just a little extra on top. It wouldn't be in their mission statement.

There will be those who are inclined to find fault that will insist that Sony is failing because of this, but personally I don't give the proverbial Rats A**** about it. Anyway my main "other" lens is a rather elderly Nikon 180mm which I don't anticipate any problems with.

Besides it provides someone with the chance to earn some pocket money / gain a reputation in providing some software to provide some PP solutions. Or of course those affected could flog off some of the Leica gear and move on.

User avatar
bfitzgerald
Subsuming Vortex of Brilliance
Posts: 3689
Joined: Fri Sep 26, 2008 10:48 pm

Re: A7 crippled sensor?

Unread postby bfitzgerald » Tue Oct 22, 2013 4:57 pm

The issue isn't just range finder lenses with adaptors, but native mount lenses too.
Which such a design (ie sensor so close to the lens) you basically are going to have real issues on the 24mp sensor at the edges and corners.
This might be one reason Sony have nothing really wide to show right now, or maybe they decided to make bigger lenses to counter act the problem.

Believe me it's def a problem for them, you don't get tele centric performance off of this type of body, not an issue so much for non wide angle, but you can forget about any kind of great performance on the 24mp sensor with a real wide angle lens.

Ironically you will get better performance with the adaptor to increase the distance from sensor to lens.
All those "hip new age no mirror zealouts" complaining about "wasted mirror space and air" you've just bitten off a lot more than you can chew. It's a lens designers nightmare, APS-C might have been not too hard, but full frame is a real challenge and far harder to do well.

The DSLR's have a lot less problems in this regard, thanks to that "mirror space" which really helps.

User avatar
bakubo
Subsuming Vortex of Brilliance
Posts: 5697
Joined: Tue Nov 06, 2007 7:55 am
Location: Japan
Contact:

Re: A7 crippled sensor?

Unread postby bakubo » Tue Oct 22, 2013 6:07 pm

Native E-mount lenses can have their own built-in tube that puts the optics further from the sensor. I imagine there already are some E-mount lenses that are like that. It makes the lenses longer, of course.

User avatar
pakodominguez
Minister with Portfolio
Posts: 2544
Joined: Tue May 22, 2007 5:38 pm
Location: NYC
Contact:

Re: A7 crippled sensor?

Unread postby pakodominguez » Tue Oct 22, 2013 6:27 pm

bakubo wrote:Native E-mount lenses can have their own built-in tube that puts the optics further from the sensor. I imagine there already are some E-mount lenses that are like that. It makes the lenses longer, of course.

That trick help Samyang (and it's incarnations) to have ready many lenses for the E-mount (specially their Cinema lenses, that don't need to be "small")
Pako
------------
http://www.pakodominguez.photo/blog" onclick="window.open(this.href);return false;

User avatar
bakubo
Subsuming Vortex of Brilliance
Posts: 5697
Joined: Tue Nov 06, 2007 7:55 am
Location: Japan
Contact:

Re: A7 crippled sensor?

Unread postby bakubo » Tue Oct 22, 2013 7:09 pm

Take a look at the length of the lenses. NEX 6 + 50mm f1.8, A57 + 55mm f1.8, and Canon 60D + 50mm f1.8:

http://camerasize.com/compact/#375.87,313.49,100.306,ha,t

NEX 6 + 55mm f1.8, A57 + 55mm f1.8, and Canon 60D + 50mm f1.8:

http://camerasize.com/compact/#375.395,313.49,100.306,ha,t

Neonsquare
Heirophant
Posts: 80
Joined: Sun Mar 07, 2010 2:36 am

Re: A7 crippled sensor?

Unread postby Neonsquare » Tue Oct 22, 2013 8:56 pm

If you take a look at some of the pictures of the new EF lenses you will see, that the back lens is sitting quite deep - so they already do this. There won't be any problem with native lenses on the A7 sensor or fwiw any adapted DSLR lenses.

User avatar
bfitzgerald
Subsuming Vortex of Brilliance
Posts: 3689
Joined: Fri Sep 26, 2008 10:48 pm

Re: A7 crippled sensor?

Unread postby bfitzgerald » Tue Oct 22, 2013 10:21 pm

bakubo wrote:Native E-mount lenses can have their own built-in tube that puts the optics further from the sensor. I imagine there already are some E-mount lenses that are like that. It makes the lenses longer, of course.


That would be pretty dumb from an engineering point of view. I've no idea of course not seen detailed shots on the new lenses, but doesn't that defeat the concept of a small body ILC system? It's possible to do that but why would you not have offset microlenses on both models?

Until we see what happens, and side by side shots we can't really tell it will be interesting to see what the story is here.

Ultra wide angle will tell us what's really going on, it's a pretty brave person to call it as no problem until one turns up.
The shots with Leica lenses on the A7 showed "massive" vignetting even fully stopped down

User avatar
bakubo
Subsuming Vortex of Brilliance
Posts: 5697
Joined: Tue Nov 06, 2007 7:55 am
Location: Japan
Contact:

Re: A7 crippled sensor?

Unread postby bakubo » Tue Oct 22, 2013 11:08 pm

Did you take a look at the length of the E-mount lenses versus the equivalent A-mount and Canon DSLR mount lenses in the link I provided? The E-mount lenses are quite a bit longer so at least in the case of those two E-mount lenses it appears that they are probably longer so that the optics are not so close to the sensor. In other words, the optics are further away from the sensor like shorter DSLR lenses are.

User avatar
bfitzgerald
Subsuming Vortex of Brilliance
Posts: 3689
Joined: Fri Sep 26, 2008 10:48 pm

Re: A7 crippled sensor?

Unread postby bfitzgerald » Tue Oct 22, 2013 11:49 pm

I can see the longer lenses, but I've yet to see any images of the lenses (ie rear element shots etc) so I can see what they've done with the elements/design.
Maybe you're right, if so I repeat the point made above.

"Dumb engineering decision"
A FF CSC with "big lenses"

That just makes no sense at all.
You start with the sensor first then build up the design from there, least that's what most normal people would do :roll:

Wes Gibbon
Oligarch
Posts: 159
Joined: Fri Jul 18, 2008 6:16 pm
Location: Peterborough, U.K.
Contact:

Re: A7 crippled sensor?

Unread postby Wes Gibbon » Wed Oct 23, 2013 12:53 am

bfitzgerald wrote:I can see the longer lenses, but I've yet to see any images of the lenses (ie rear element shots etc) so I can see what they've done with the elements/design.
Maybe you're right, if so I repeat the point made above.

"Dumb engineering decision"
A FF CSC with "big lenses"

That just makes no sense at all.
You start with the sensor first then build up the design from there, least that's what most normal people would do :roll:


Do you mean the design of the camera or design of the lenses?

User avatar
pakodominguez
Minister with Portfolio
Posts: 2544
Joined: Tue May 22, 2007 5:38 pm
Location: NYC
Contact:

Re: A7 crippled sensor?

Unread postby pakodominguez » Wed Oct 23, 2013 4:09 am

bakubo wrote:Did you take a look at the length of the E-mount lenses versus the equivalent A-mount and Canon DSLR mount lenses in the link I provided? The E-mount lenses are quite a bit longer so at least in the case of those two E-mount lenses it appears that they are probably longer so that the optics are not so close to the sensor. In other words, the optics are further away from the sensor like shorter DSLR lenses are.

Not really (as you can see on the diagrams):
http://www.sony.net/Products/di/en-us/p ... 5f28z.html
http://www.sony.net/Products/di/en-us/p ... 5f18z.html
Pako
------------
http://www.pakodominguez.photo/blog" onclick="window.open(this.href);return false;

User avatar
Greg Beetham
Tower of Babel
Posts: 6155
Joined: Sun May 27, 2007 3:25 pm
Location: Townsville, Qld. Australia
Contact:

Re: A7 crippled sensor?

Unread postby Greg Beetham » Wed Oct 23, 2013 4:48 am

Some FE’s are recessed, and some have rear elements that are as big as the objective element, but then some rear elements in A-mount lenses move a long way forward when in use also.
http://www.sony.net/Products/di/en-us/products/lenses/lineup/detail/sal2470z.html
http://www.sony.net/Products/di/en-us/products/lenses/lineup/detail/sel2870.html
Greg


Return to “Alpha E-Mount system”

Who is online

Users browsing this forum: No registered users and 3 guests

cron