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10-06-2013, 01:15 PM   #31
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Excellent manual focus tracking on that shot - well done.

10-07-2013, 11:39 AM   #32
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Sony will launch their first Full Frame E-mount photocameras on October 16

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Sony will launch their first Full Frame E-mount photocameras on October 16. And it looks like Sony’s goal was to price the new cameras as low as it gets! Here are some info:

The A7 has 24Mp and on sensor PDAF. It has a built-in EVF (middle of the camera) and is weather sealed. Price should be around 1600-17000 Euro/Dollars for the body and close to 2000 Euro/dollars with the 28-70mm FE kit lens.

The A7r has a 36MP sensor. Like the A7 it has a built-in EVF (middle of the camera) and is weather sealed. price is around 2,300-2,400 Euro/Dollars for the body. No info on the kit price.

The A7 and the A7r have exactly the same look but a different sensor. All current E-mount lenses will work in crop mode on these cameras. The new Full Frame E-mount lenses coming along the camera are the 24-70mm Zeiss (not sure about the aperture but it could be f/2.8), 28-70mm f/3.5-4.5, 35mm f/2.8 Zeiss and a 55mm f/1.8 Zeiss.
Sony A7 and A7r will be cheap (and without IBIS). | Mirrorless Rumors


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1) The A7 uses a 24 megapixel sensor with on sensor PDAF. It has an Anti Aliasing filter. This camera is more suited for sport or video recording
2) The A73 uses a 36 Megapixel sensor that has no PDAF on sensor. And it also has no Anti Aliasing filter just like the Nikon D800E. The camera is more appropriate for High resolution photography (like Landscape pics).

Both cameras have the same body (with built-in EVF in the middle-top of the camera). Both are weathersealed. Size close to the current RX1/R. The A7 costs around 1600-1700 Dollars (or Euro) and the A7r costs around 2300-2400 Dollars (or Euro).
(SR5) A7 has on sensor PDAF while A7r has not (but comes without AA filter). | sonyalpharumors
10-07-2013, 01:42 PM   #33
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I am a bit disappointed that the A7r doesn't have PDAF. What an oddball omission. Every camera, at 5 series and above, should have it going forward. An A7r might be a landscape specialist, but that doesn't mean someone won't want to use it with tracking AF. Do they expect people to buy both cameras?
10-07-2013, 02:12 PM   #34
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QuoteOriginally posted by kenafein Quote
I am a bit disappointed that the A7r doesn't have PDAF. What an oddball omission. Every camera, at 5 series and above, should have it going forward. An A7r might be a landscape specialist, but that doesn't mean someone won't want to use it with tracking AF. Do they expect people to buy both cameras?
Assuming the rumour is true (and I generally don't trust rumours) it makes sense to me.

On sensor PDAF comes at the expense of resolution - and it's resolution in the centre of the frame, where it matters the most. It's one of the reasons why Nikon and Canon have been so hesitant putting it into their high end cameras.

I have been avoiding shooting with Leica lenses on my NEX6 for the same reason - I generally use M-mount with my NEX-F3, and use Sony lenses with the NEX6.

Buying both cameras is not a bad idea - use the A7r with high quality manual focus lenses and use the A7 as a more general purpose camera with AF.

I actually prefer the focus peaking on the K-01 than the NEX - I am secretly hoping Ricoh may release a full frame GXR M in the future.

10-07-2013, 02:52 PM   #35
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QuoteOriginally posted by Christine Tham Quote
Assuming the rumour is true (and I generally don't trust rumours) it makes sense to me.

On sensor PDAF comes at the expense of resolution - and it's resolution in the centre of the frame, where it matters the most. It's one of the reasons why Nikon and Canon have been so hesitant putting it into their high end cameras.

I have been avoiding shooting with Leica lenses on my NEX6 for the same reason - I generally use M-mount with my NEX-F3, and use Sony lenses with the NEX6.

Buying both cameras is not a bad idea - use the A7r with high quality manual focus lenses and use the A7 as a more general purpose camera with AF.

I actually prefer the focus peaking on the K-01 than the NEX - I am secretly hoping Ricoh may release a full frame GXR M in the future.
Personally, I think the NEX focus peaking is much better than the K-01. Being able to change the colors alone is worth it.

It is true that you lose some pixels, perhaps even an entire row of pixels, per row in the array, but I really can't tell the difference. On a 36mp sensor, at 7,360 x 4,912, you would lose maybe 20 rows. So the effective resolution will be 7,360 x 4,892. The images from my 5N and from my NEX 6 look the same to me. They aren't going to be able to get around adding them to the sensor in their A-mount cameras. The quality of those sensors had better be top notch, or Sony will have an even worse marketing problem than with the pellicle mirror. I assumed that the decision was because this camera really can't take advantage of tracking focus, because the buffer won't be able to handle those huge images anyways.

I'd love to have both cameras, but that's not practical for most people. I can certainly see the A7r putting a dent in M 240 sales. I would like a more well rounded camera, however. I can't justify buying both, but they are much more reasonably priced than I expected. I was hoping for the rumored 32mp sensor and 4GB buffer for both cameras, oh well. .
10-07-2013, 03:12 PM   #36
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QuoteOriginally posted by kenafein Quote
Personally, I think the NEX focus peaking is much better than the K-01. Being able to change the colors alone is worth it.
Yes, but the K-01 seems to be much more precise at indicating the optimal focus - the NEX is a little more hit and miss and requires me to zoom into the image (which is not useful when focus tracking).

I am a little old school, I prefer to focus track using manual focus (trick I learnt from doing video) rather than rely on camera AF. Our brains seem to be much better at anticipating the likely direction of the movement of the subject by the time the shutter is released taking into account shutter lag, compared to AF.

Here's the result from focus tracking an ambling koala taken on DA70 on a K-01 (if I can be forgiven for the heinous sin of posting a Pentax photo in the non-Pentax camera section of a Pentax forum!):
10-07-2013, 03:24 PM   #37
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QuoteOriginally posted by kenafein Quote

It is true that you lose some pixels, perhaps even an entire row of pixels, per row in the array, but I really can't tell the difference. On a 36mp sensor, at 7,360 x 4,912, you would lose maybe 20 rows. So the effective resolution will be 7,360 x 4,892.
I am not sure about the Sony, but on a Canon this is how many pixels are lost in a Hybrid PDAF sensor:


And this is a 100% resolution crop of above:
10-07-2013, 03:49 PM   #38
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QuoteOriginally posted by Christine Tham Quote
I am not sure about the Sony, but on a Canon this is how many pixels are lost in a Hybrid PDAF sensor:


And this is a 100% resolution crop of above:
Canon does have the more interesting technology, where they can use any pixel for each function. However, their Hybrid-PDAF solution is used for video tracking. When you shoot video you are already line skipping. For a 1080p video you are already skipping 3 out of 4 rows, of a 24mp sensor. I imagine they have a different setup for stills. On the NEX 6, there are 99 pixels devoted to PDAF; and, unfortunately, they are unable to toggle the pixel's function. I don't think it will greatly reduce the resolution with the Sony setup, and I think the Canon setup is optimized for video. Canon still uses PDAF for stills and reverts the pixels to data gathering only.

10-07-2013, 03:52 PM   #39
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QuoteOriginally posted by Christine Tham Quote
Yes, but the K-01 seems to be much more precise at indicating the optimal focus - the NEX is a little more hit and miss and requires me to zoom into the image (which is not useful when focus tracking).

I am a little old school, I prefer to focus track using manual focus (trick I learnt from doing video) rather than rely on camera AF. Our brains seem to be much better at anticipating the likely direction of the movement of the subject by the time the shutter is released taking into account shutter lag, compared to AF.

Here's the result from focus tracking an ambling koala taken on DA70 on a K-01 (if I can be forgiven for the heinous sin of posting a Pentax photo in the non-Pentax camera section of a Pentax forum!):
As always, I defer to your greater skill. You are a much better photographer than I am. I eagerly tried a K-01, on your recommendation, but I didn't find it any more accurate. Perhaps it's because I was always wondering if it was in focus, or if I was just seeing things. To be fair, I didn't have enough time with it. I can't say I had any better luck with my Pentax Q, however. It works well enough, but I'd really love to be able to change the colors.
10-07-2013, 04:51 PM   #40
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QuoteOriginally posted by kenafein Quote
On the NEX 6, there are 99 pixels devoted to PDAF; and, unfortunately, they are unable to toggle the pixel's function.
Slight correction - according to Sony documentation, the NEX6 has "99 points(phase-detection AF)/25 points(contrast-detection AF)" - each PDAF "point" consists of multiple pixels (not sure how many, but Sony implies each "point" has cross hair focusing).

I agree that it's debatable whether it's noticeable or not (I imagine my NEX6 shots seem ever so slightly softer in the centre, but it's my imagination I suspect).

In any case, IF the rumour is true (and that is a very big IF) then I am sure Sony engineers have a good reason for omitting on sensor PDAF for the higher speced model - they are not fools (I had an opportunity to speak to some of them when they visited Sydney last year - I can assure you they are passionate about image quality - they were quite amused when I showed them my brand new RX100 - at the time).
10-07-2013, 04:54 PM   #41
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QuoteOriginally posted by kenafein Quote
I am a bit disappointed that the A7r doesn't have PDAF. What an oddball omission. Every camera, at 5 series and above, should have it going forward. An A7r might be a landscape specialist, but that doesn't mean someone won't want to use it with tracking AF. Do they expect people to buy both cameras?
Falk Lumo has said that he believes PDAF on sensor is a dead end technology, not a long term solution to issues of contrast detect auto focus.
10-07-2013, 05:49 PM   #42
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QuoteOriginally posted by Rondec Quote
Falk Lumo has said that he believes PDAF on sensor is a dead end technology, not a long term solution to issues of contrast detect auto focus.
He also said that Canon's Dual-Pixel AF solution will revolutionize the industry. Perhaps, when they get the Foveon style technology working, they can add a layer simply for PDAF detection. Let's push things forward.


QuoteOriginally posted by Christine Tham Quote
In any case, IF the rumour is true (and that is a very big IF) then I am sure Sony engineers have a good reason for omitting on sensor PDAF for the higher speced model - they are not fools (I had an opportunity to speak to some of them when they visited Sydney last year - I can assure you they are passionate about image quality - they were quite amused when I showed them my brand new RX100 - at the time).
That maybe. I am no engineer(well, I am, but not that kind of engineer), however, it seems like a vote of no confidence for their auto-focus technology of choice.

Olympus is using Hybrid-PDAF detection on their new camera, and they have fewer pixels to give up.
10-07-2013, 11:13 PM   #43
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QuoteOriginally posted by kenafein Quote
it seems like a vote of no confidence for their auto-focus technology of choice.
1. We don't know if the rumour is true.
2. Even if it is true, we don't know the reason why the feature is omitted. We can speculate, but it's speculation. It's easy to criticise when we don't understand what the design objectives, parameters and trade-offs are.
3. I don't recall Sony ever claiming that PDAF is their "technology of choice."
4. Arguably, PDAF is inferior to CDAF. It actually trades off accuracy for speed (PDAF doesn't understand what it's focusing on - it's just an optimisation on a set of transfer functions - CDAF on the other hand can take the entire image into account - and can do things like object recognition to figure out what to focus on).
5. Arguably, if CDAF can be made to be "fast enough" (and this is something Sony can and will improve on) then PDAF is not necessary.
6. I don't believe (based on personal observation, not necessarily factual) that PDAF is the "primary" AF mechanism on the NEX6 (for the reasons provided in point 4). Rather, I believe PDAF is used to assist CDAF by reducing hunting and improving focusing speed. This is in contrast to the Nikon 1, which seems to primarily rely on PDAF, and falls back to CDAF when it's unsure.
7. Supporting evidence for 6: I have two of the kit zoom lens - one with the PDAF firmware update applied, one without. If I swap between the two lenses on the NEX6, they both focus in approximately the same time, but there are certain situations where the one with the PDAF firmware is faster, but these situations are not common.
10-08-2013, 02:39 AM   #44
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QuoteOriginally posted by Christine Tham Quote
1. We don't know if the rumour is true.
2. Even if it is true, we don't know the reason why the feature is omitted. We can speculate, but it's speculation. It's easy to criticise when we don't understand what the design objectives, parameters and trade-offs are.
3. I don't recall Sony ever claiming that PDAF is their "technology of choice."
4. Arguably, PDAF is inferior to CDAF. It actually trades off accuracy for speed (PDAF doesn't understand what it's focusing on - it's just an optimisation on a set of transfer functions - CDAF on the other hand can take the entire image into account - and can do things like object recognition to figure out what to focus on).
5. Arguably, if CDAF can be made to be "fast enough" (and this is something Sony can and will improve on) then PDAF is not necessary.
6. I don't believe (based on personal observation, not necessarily factual) that PDAF is the "primary" AF mechanism on the NEX6 (for the reasons provided in point 4). Rather, I believe PDAF is used to assist CDAF by reducing hunting and improving focusing speed. This is in contrast to the Nikon 1, which seems to primarily rely on PDAF, and falls back to CDAF when it's unsure.
7. Supporting evidence for 6: I have two of the kit zoom lens - one with the PDAF firmware update applied, one without. If I swap between the two lenses on the NEX6, they both focus in approximately the same time, but there are certain situations where the one with the PDAF firmware is faster, but these situations are not common.
You never know until the official release, but they are usually pretty accurate, especially when it is this close. Hybrid pdaf is what they are using to drop the slt, for a-mount. It is true that pdaf is secondary for the NEX, but I have found it to be a dramatic improvement, especially for tracking moving objects. The AF in my NEX 6 is superior to my k5. Regardless of the reason for the omission, if it is true, I will be somewhat disappointed.
10-08-2013, 07:54 AM   #45
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QuoteOriginally posted by bossa Quote
How many Pentaxians are about to buy a Sony FF to mount their FF glass? This would seem to be another so-called nail in the coffin for a Pentax FF unless they happen to surprise everyone and release a FF as well as the rumoured K-3 in a couple of weeks.
Irrespective of Pentax releasing FF or not, I am going to buy A7 and unlikely to buy Pentax or any other FF DSLR, the primary reason is the size. I have become so comfortable with NEX size, swivel LCD etc that I was hardly using my DSLR, eventually sold k-x, k-5 and just kept k-01.
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