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nimrodisease
17-10-2013, 8:22am
Full frame, 36 megapixel, weather sealing, no low pass filter.. all in one tiny package!

I will be interested to see how this little guy stacks up against the likes of a D800E.

arthurking83
17-10-2013, 11:08am
Yep! Interesting, and not too much of a surprise really.
Small compact 35mm cameras have existed for over 60 years, so there's nothing new here other than the combination of already available parts.

One I can foresee tho is that Sony traditionally has a history of not utilising the sensor to it's fullest capacity, and this usually manifests in more noise in images as ISO settings increase.

A7 is nothing to sneeze at either .. 24Mp, and PDAF(on sensor) with higher frame rate burst mode.

My main interest would be the possibility of mounting all manner of weird and wonderful lenses with fewer restrictions.

One concern tho is this notion of smaller and more compact and lighter:

The new 55mm f/1.8 dimensional specs are as follows:
281 g (0.62 lb)
Diameter: 64 mm (2.52″)
Length: 71 mm (2.80″)

The Nikon 50mm f/1.8(AF-S):
Approximately 185 g/6.6 oz
Approximately 72 x 52.5 mm/2.8 x 2.1 in.

So this new Sony/Ziess lens (with it's shorter register distance) is only 1mm narrower in diameter, and yet massively oversized by comparison to the Nikon 'equivalent' in other areas(100g heavier!).

It's basically the same if you compare the new 35/2.8 ZA prime against the old Nikon 35/2 AF-D .. dimensions are damn near identical except that the Zeiss weighs in at 120g and the Nikon weights in at 200g(which you would expect with a 1 stop aperture size advantage anyhow.

So where is this supposed size/weight advantage?

I @ M
17-10-2013, 11:54am
So where is this supposed size/weight advantage?

In the Sony marketing dept's mind.

Never let facts get in the way of good advertising. :D

arthurking83
17-10-2013, 2:02pm
So far the biggest issue with this new camera(system) is the lack of native lenses for it.
I'm sure Sony will redress this, but what's interesting is Samyang's latest announcement (http://www.dpreview.com/news/2013/10/16/samyang-announces-five-full-frame-e-mount-lenses?utm_campaign=internal-link&utm_source=news-list&utm_medium=text&ref=title_0_6)

Good on 'em, I say.

But I had to laugh when I read this bit:


".... As these are essentially SLR lenses with an adapter tube permanently fitted, they won't offer any of the size advantages achievable by 'native' lenses."

I guess by size advantages they're referring to something along the lines of the comparison between the ....

Sony/Ziess 28-70mm f/3.5-5.6 OSS:
426 g (0.94 lb)
Diameter 73 mm (2.87″)
Length 95 mm (3.74″)

.. and Nikon's much bigger 24-85mm f/3.5-5.6VR:
Approximately 78 x 82 mm/3.1 x 3.2 in.
Approximately 465 g /16.4 oz


(Nikon no longer make their AF-D 28-70/3.5-5.6, but it's dimensions were: 68 x 71 mm and 355g !!)

Granted the camera body itself is smaller, and there are images of the camera in hand on DPR .. but again I had to laugh when these camera in hand images are noteworthy for the use of a female hand, where traditionally DPR use male hands for their camera in hand images.
Doesn't look like there's any room between any of the current lenses and the grip for fingers to fall/seat naturally, so the grip itself is almost certainly going to require the use of fingers to grip it .. not the palm of the hand.

That was my biggest issue with the D600 vs D800(and also D300) .. where my hand naturally fits around the grip perfectly so the palm takes up all the pressure/weight, with the D600 I had to use my fingers to grip the camera firmly. Makes your fingers cramp up after continual usage.

But I'm sure all the streetshooting folk will wax lyrically about this camera too now.

It's still an interesting camera tho.

swifty
18-10-2013, 2:38pm
I can't fault Sony for their engineering. I think they really do a good job pushing technological boundaries but I find their product range not particularly focussed.
It seems that they're trying to compete at every level of every segment.

I do like the A7 and A7r but as others have noted, the lens line up's not particularly exciting atm and leaves me questioning what market its aimed at and how much manufacturer commitment I'd get moving forward before Sony decides to concentrate on the next in thing. I don't feel they've really fleshed out any of their existing modular lines that already includes A-mount FF, A-mount APS-C and E-mount APS-C.

In terms of size, the mirrorless size advantage has always mostly been in the body. The lens still needs to cover the larger image circle so I'd expect most lenses to be comparable to existing retrofocal DSLR lenses covering the same imaging area. This was the case with the NEX APS-C cameras where bodies were as small and sometimes even smaller than m4/3 as well as Nikon CX cameras. But in terms of lenses, you could see a clear progression in size for each successively larger format.

What's also interesting is whether the E-mount was ever intended for FF, or an after thought when they realised it could accommodate one. Mounts such as m43 have diameters far large than the sensor size they cover as a design feature to allow for more design freedom in optics to avoid light striking at oblique angles at the periphery although microlens advances have mitigated a lot of that issue.
With the initial NEX E-mount system, people didn't really think it could accommodate a FF sensor until Sony surprised everyone with a FF NEX mount video camera in the VG-900. So how much this E-mount diameter design would compromise FF E-mount lens design is anyone's guess. Its already been noted the micro lens design on the A7r are modified/off-set for better corner performance. It'd be interesting to see how corner performance stack up between the A7 and A7r. Whether the mount diameter compromises lens design also remains to be seen but I suspect in Sony's fashion, even if it does they'd engineer a technological solution.

Furthermore, I've read some sound commentary about the use of adapters with MF legacy lens and the tolerances needed at this level of imaging (the Leica red dot crowd). Much have been said about the shooing discipline required on the Nikon D800/Es to irk out all its image quality potential and even with its native mount, some have found native lenses to have inadequately strict tolerances. Add an adapter and the problem's bound to get worse.
But of course the ability to adapt practically any lens (with 35mm lens at their native FOV particularly) cannot be undervalued.

Lance B
18-10-2013, 6:51pm
I wonder if they have overcome the vignetting that can occur with the closer lens to sensor register distance due to the angle of light hitting the pixels?

arthurking83
18-10-2013, 8:13pm
I wonder if they have overcome the vignetting that can occur with the closer lens to sensor register distance due to the angle of light hitting the pixels?

In camera processing is almost certain to take care of any vignetting if present with native lenses(or compatible lenses via compatible adapters), and people are referring to microlens design optimised for this purpose too.
But (according to many of these discussions) if microlenses are optimised for native lenses(ie. short register distances), then issues will arise with lenses made for longer back focus distances.

That is, if the microlenses are oriented in such a way for native short register lenses, then they won't be optimised for lenses from other longer register lenses, and excessive vignetting should result(wth say, Nikon or Canon, or M42 lenses .. unless the imaging circle of the lens is overly large to begin with).

I guess only time will tell once images start to surface on the web.


One would assume that adapters made by higher quality manufacturers with bayonet type mounts should generally not be an issue. I think most of the elevated price in these accessories is due to higher levels of engineering and stricter quality controls.
The cheaper ebay adapters are almost certain to be where the issue is at.

Having said that, I've got quite a number of 'cheap' adapters, mainly M42/M39, for my D800E and I've yet to experience any issue with these cheap adapters.
Haven't done any really strict quality testing, just casual observations so far, but they all look to be within acceptable quality.
In fact one of my cheap old one lenses(Schacht) on a cheap M42 focusing helicoid has shown indications that it may be the best lens setup I currently have(for macro).

hoffy
10-11-2013, 10:58am
Since I'm in the neighborhood....

I have to admit I am quite intrigued by the A7 in particular. I think that this may be a good travel companion, with the added plus of being able to use my existing lineup (with the right adapter, of course).

Of a curios note, from what I have read, the camera will be introduced including the adapter VIA redemption. So, one could be into a 35mm sensor, utilising all there existing minolta AF/Sony Alpha lenses for $1800. I just wish I had the money now, as I would nearly be pre-ordering.