[Xperia Z General] caitsith01:
Lots of people are unhappy with the camera on the Z. I'm into photography and I thought I'd have a play with it to see what I could find out. I thought I'd post this as it may help people get more out of the camera and understand why they are getting bad results. I was initially very unhappy with low light shots, especially compared with my old Xperia Arc. I am now getting vastly better results.

1. "Superior Auto Mode" SUCKS. Really, really sucks.

Why?

First, it applies some sort of hyper-aggressive noise reduction/sharpening to most images. This means that even if you get a good capture, this mode then does its best to ruin it for you by artificially stuffing up details and actually adding noise (via over-aggressive processing).

Second, it does really stupid things with ISO. You may notice that on manual settings, ISO only goes up to 1600 (which is still way too high for this sensor). However, in auto, the camera will go up to at least ISO 2500 (confirmed by checking exif data). This is extremely bad for image quality and introduces huge amounts of colour noise which simply cannot be overcome by post processing. In addition, in auto mode the camera is very "high ISO happy", so it will bump up the ISO very quickly even in moderately good conditions.

What's more, while you can't use the (dubious) image stabilisation at manual ISO settings, you can you HDR. So you can get good night or dusk shots by using HDR and (say) ISO 400 in normal mode, which I deal with below.

Overall, I would avoid this mode unless you are in bright conditions or just need to get a basic shot without caring about quality.

2. HDR mode is real, but the images it takes are not taken simultaneously.

I'm sure I read Sony claiming that the sensor was in some way three layered and therefore that it could take HDR shots instantly. The reality is that while HDR mode works (weakly), it actually takes three separate shots over the space of maybe half a second.

The problem with this is that if things are moving in your image, they will either blur or have ghosts of themselves in the photo.

I verified this by taking an HDR shot of traffic at an intersection. I was able to see very dark and very light 'ghost' images of moving cars, even though the rest of the image was sharp and clear.

From this I am guessing that Sony has implemented an edge-matching algorithm to process the three exposures into one. This can cope with some camera shake, but cannot cope with actual fast moving objects. This theory is supported by the fact that the image size drops by one megapixel for HDR, i.e., the camera is giving itself a "border" to allow for shake.

It is also apparent that the level of HDR processing is very weak compared to what is possible with a proper camera and proper software. The exposure range and the amount of weight given to the high and low range exposures is very weak (confirmed by the level of saturation of the "ghost" cars in my test image, which were fairly faint).

Others have reported that the video quality suffers with HDR on. This is consistent with the HDR having to take triple the exposures then process them on the fly.

3. Image stabilisation is a gimmick

In manual mode, you can turn on image stabilisation. However, when you do this, you can't set a manual ISO level and can't use HDR. This strongly suggests that all that "image stabilisation" is really doing is messing with your ISO settings (as per "superior auto mode") to increase shutter speed in difficult conditions by ramping up ISO. This, of course, destroys quality.

4. You can use normal mode to control the ISO and get much better results, including at night

If you choose "normal" shooting mode, and then go to settings and scroll down, you will find an option to set the ISO of the camera manually.

Playing with this, I have been able to get much, much better results from the camera than are achievable either in "superior auto" mode or in any mode where ISO is set to "auto".

Specifically, I would say that the camera produces fair to excellent results (for a phone camera) at any ISO below 400, and acceptable results at 800 in some conditions. However, 1600 produces very noisy images and should be avoided if you are after image quality (as should 800, to be safe). That is consistent with the size of the camera and sensor. Even fairly good consumer DSLRs struggle at or above 1600, so it is not surprising that a tiny phone camera struggles at or above 800.

Using the camera at ISO 400 I have been able to take shots in very dark conditions which look great and show relatively little noise.

The lens is f/2.4 at its fastest, which is not ultra fast, but fast enough to capture a decent amount of light at ISO 400 or 800. You are better off sticking to these ISO levels and trying to physically stabilise your camera (i.e., balance it on something solid) than killing you image quality with higher ISO settings.

A comparison suggests that "normal" mode doesn't apply the stupid levels of sharpening and noise reduction (so called) that superior auto mode does. Shots seem to retain most of the natural sharpness and detail that the camera is clearly capable of producing.

5. The flash is bad but better than most

Direct flash generally sucks, and mobile phone flashes generally suck. Combine them for a lot of suckiness.

However, Sony has done a solid job with this flash, given the baseline difficulties with any direct flash. It doesn't seem to blast its subject and it seems to be at a low enough level to let ambient light fill in the background. I was able to get acceptable results in normal mode at ISO 400.

6. Metering

The metering on the camera is quite aggressive in its centre-weighted variation. If you are finding that photos of a light or dark object are causing the rest of the scene to blow out or go too dark, try the full averaged metering mode (which is slightly dark, but does a decent job).

7. My suggested settings

A. Daytime: Normal mode; ISO 100; HDR off (to avoid ghosts on moving objects); flash off.

B. Nightime: Normal mode; ISO 400; HDR off unless taking pics of buildings and holding camera v steady; metering full scene; flash off.

C. I want to produce horrible photos then complain: Superior Auto Mode.

I hope this helps someone! Using setting A above this camera produces some stunning pictures in good light. Using setting B it produces very good night pictures for a camera phone, particularly if you shoot at the highest resolution then resize later.