Thinking of getting A550...

[Yinfinity]

After few minutes of actually trying out the face detection function I found out that the camera indeed uses the live-view sensor for face detection however the focusing is still done by the phase af sensors. This means under live-view mode faces will be detected automatically and all you have to do is put the camera on wide area focus mode which activates all the phase af sensors and point anyone of the phase autofocus spot at a face and the camera will focus without you pressing any button. Therefore contrast and phase af work together for face detection.

When the smile shuttle function is on the camera doesn't even allow selection of autofocus spots which probably means only contrast autofocus is at work. One thing for sure no phase af sensor can detect smiles which is only possible through the live-view sensor.

 

[Ouverture]

Yes. Face detect normally is active only within the 9 pts af area is in focus. Other than that, it doesn't seem to detect any faces if it's out of the af pts range.

 

[Yinfinity]

Yes. Face detect normally is active only within the 9 pts af area is in focus. Other than that, it doesn't seem to detect any faces if it's out of the af pts range.

Correction: Faces are detected as long as they are in the view as evident by the white squares framing the many faces on the lcd screen though they are not in focus. The white coloured square frame will turn red indicating a correct focus when a phase af point in green is moved into it.

Anyway, face detection on a500/50 really works and rocks. It's faster than having to select the focus point yourself and definitely deserves more than the gimmick statues it has now. Hopefully the a700 replacement will have this wonderful function and let it pass down as a tradition just like the in-body stabilizer and the unique live-view implementation.

 

[rontth]

I'm thinking of getting the Sony A550 with CZ1680.
MS color has quoted me $2290 for this combination.

Is this a good price? Does anyone know of a better pricing for this combination?

Thanks....

 

[MontoyaSG]

I'm thinking of getting the Sony A550 with CZ1680.
MS color has quoted me $2290 for this combination.

Is this a good price? Does anyone know of a better pricing for this combination?

Thanks....

It's more or less within this price range. If you want can get quotes from other stores to compare.

 

[tsan81]

I'm thinking of getting the Sony A550 with CZ1680.
MS color has quoted me $2290 for this combination.

Is this a good price? Does anyone know of a better pricing for this combination?

Thanks....

Alternatively, go check out sony style shops (not website). A550 + 16-105mm (not CZ) = $1799

 

[Ouverture]

I know it uses phase detect af, but I doubt face detection uses the phase af sensors as well. It is technically difficult/impossible to detect shapes with phase af sensors alone. Phase detection af works by analyzing light with a limited number of sensors whereas contrast detection focuses by contrast and shape with the aid of in camera computer chips. There must be a reason that face detection is only accessible through the Fn button when the camera is on live-view mode.

There is a simple way to prove this. Just try to use the face detection function to focus on a face that is located on one extreme corner of the frame where no phase detection af sensor is assigned to. If it still works then it must be face detection by contrast, at the same time with the availability of point focus by phase af sensors.

Seems Sony's Face detection is using Phase Detect...

http://www.alphamountworld.com/reviews/sony-dslr-alpha-a550-review?page=0%2C3