Sony's new NEX5 - the higher end of the two APS-C "Compact System Camera" models introduced this week - uses lenses made at a new facility in Thailand. In fact, Sony executives say the Thai factory was producing the entire Alpha NEX range, leaving existing production lines free for the continued development of the DSLR models.

With a brief experience using two of the lenses only - the 16mm f/2.8 pancake and the 18-55mm "kit" stabilised zoom - I can make no conclusions about the usefulness of the system. The 16mm f/2.8 is clearly very good, once stopped down to f/5.6, but benefits from chromatic aberration reduction when processing, or some fringes may appear. The 18-5mm is frankly nowhere near as good as the Sony SAM 18-55mm f/3.5-5.6 DT lens for the conventional Alpha system, if my sample is any indication. Sharp central detail was lost towards the edges across the entire focal length range of the lens, with the corners below standard even when stopped down to a sensible f/8 or so.

However, filing a single image from Croatia with Alamy, the result (from a 14 megapixel JPEG) proved acceptable, no doubt because of the very high central sharpness. The DSLR lens, in contrast, has more even coverage into the corners and is one of the better lenses I've used in this class. The NEX lens reminds me more of the first 18-55mm kit lenses such as the original Canon EF-S I first used with a 300D.

The 16mm f/2.8 is an entirely different matter, very sharp even wide open, although there is some expected softening to the corners at this setting - much as you will find when a 24mm f/2.8 is used on full frame digital. Geometry compares favourably with traditional 24mm wides, its equivalent angle of view. No doubt the 18mm back focus (compared to 44.5mm for the Alpha DSLR) has made this very small and neat lens easier to design with good optical characteristics.

The NEX5 has the same basic sensor as the cheaper NEX3 (the key differences are mainly to do with HD video), and performed well throughout the Auto ISO range of 200-1600, with noise reduction starting to affect detail at the highest setting. Manual ISO goes up to 12,800 and it seems very close to the Alpha 550; you might use ISO 800 without worries, ISO 1600 when needed, but 3200-6400 are strictly for low light and 12,800 is an emergency setting. I was able to use Sony's raw converter, but no other, and any serious assessment of the files must wait until mainstream converters have been updated to handle the files.

The Sweep Pan function seemed to work very well for Sony's Paul Genge, but my attempts to keep the sea horizon level on a screen grid line failed. The horizon ended up with visible steps, and foreground objects had serious jumps in alignment, when shooting an otherwise impressive 23 megapixel superwide pan some 12,416 pixels in length.

However, there's a big difference between this sweep pan mode and previous consumer camera pans. They are video-based, taking (normallly) a panned 720p video with a fast shutter speed. This mode shoots a motordrive sequence at 7fps, of still frames with an 1856 pixel high size per image, and a standard pan of 8192 pixels or the ultra-wide pan of 12,416. The result is sharp enough for picture library use as well as big enough. The rules for a good stitched pan are well enough known - do not use wide-angles, have the tripod high off the ground, avoid strong foreground elements, and use a pan head with a spirit level.

Sony's system allows a freehand pan and the best lens geometry was the 16mm - and my tripod was the Gitzo Traveller 6X, which has a small ball and socket, unsuited to level panning. But I had one success, a standard pan shot vertically in the Ivan Mestrovic Museum Gallery gardens, which shows no jumps or stich errors. Clearly the camera can be used for very high quality sweep pans if the technique is mastered,

The pan can use video mode for one purpose - 3D pans. We were able to view these, scrolled across using a Playstation controller, on a Sony 3D Bravia TV. It was impressive. But the cheapest Bravia 3D TV is £1600 - it seems that the files may work on some other alternate-polarising TVs like Samsung, but there is no guarantee. Sony of course recommends Bravia.

On the basis of exhausting one battery and putting 2.8GB of data on a Memorystick Duo Pro card, it's too early to say if I would recommend the NEX5. The 18-200mm "travel and sports" zoom will be at least £550 and could be more than £700 (vagueness on this front from Sony was probably due to kit versus separate sale pricing). It would have to be a different class of glass to the 18-55mm to interest professional users. If not, the only really good lens of the three shown or promised is the 16mm pancake.

While this is far more attractive than the relatively neutral focal length of the 17mm and 20mm options offered by Olympus and Panasonic for the smaller Micro Four Thirds format, not everyone wants an 84° angle of view for their walkaround pocketable lens. An equally small fast 30mm would be useful. Also, an optical viewfinder at £130 harks back to the excessive pricing for such items in past rangefinder systems; if the lens is little more than £200, how can a mere viewfinder be that much?

An EVF (electronic viewfinder) for the NEX models would seem to be a necessary future product, because without it the camera can not attract many older European users - poor eyesight is widespread over the age of fortysomething, and the rear screen composition that comes so easily to most under-thirties hits a difficult focusing zone for far too many potential buyers.

But, as Sony's videos show, they believe this camera system is there to tumble around joyously in an exhilarating world of young fun and fast action.

It takes 0.3 seconds to focus on a subject once up and running. It takes, sometimes, over a second to wake up and decide it wants to focus. It's no point-and-shoot, street photo, decisive moment grabbing tool. But you can't help liking it - the NEX is clever and probably the best such camera made, at least the 1080i NEX5. I have not bought any of its rivals; I've tried them and decided to wait. I'm going to wait a bit longer. Photokina in September will bring so much more choice; this type of camera, which Sony may decide to dub CSC (Compact System Camera), is in its infancy and will one day, I guess, replace the single-lens reflex, which embarked on its rise to popularity 50 years ago (1958-9)… and the AF SLR 25 years ago (1985-6)… and the DSLR (10 years ago).

The NEX3, though limited to 720p HD video, has all of the important features of the 5 in a polycarbonate body. With Jessops, for example, offering a pre-order price of £449 with the 16mm lens, flash, ever-ready style case, and seven-inch Sony digital photo frame (about £100 value of free accessories), it costs little more than many compacts.

One very interesting comparison is with the Sigma DP-1s at £399. This has been a popular choice with its fixed 16.6mm f/4 lens and 1.7x, 4.7 true megapixel Foveon sensor (claimed to match 14 megapixels). The NEX3 makes a very similar sized packaged with a significantly wider angle, faster lens and a better 14 megapixels, ranging to a usable ISO 3200 rather than a usable 800. It also shoots video and the lens is interchangeable.

While the Sigma has also faced competition from Micro Four Thirds, this has only offered 17mm f/4 or 20mm f/2.8 pancake lenses on a 2X sensor factor - equivalent, more or less, to 35mm and 40mm focal lengths in full frame terms. The Sigma 16.6mm is equivalent to a 28mm, but the NEX system 16mm matches a 24mm. The size and extra resolution of the sensor nullify any arguments that this is too wide an angle. Simply crop to 12 megapixels or to 10 megapixels (the real output performance of the Sigma) to reduce the field of view, and you still have as much image data as the others offer.

You can see a short video shot at the Croatian event by David Kilpatrick using the NEX5, mainly after dark.

And also a gallery of 48 full size, in-camera JPEGs from the NEX5, taking by David Kilpatrick during the event

Paul Genge of Sony UK has made the following comment on findings about lens quality:

"All products we provided were pre-production. They were near final quality, but we have subsequently discovered that attendees were discovering some lenses were better than others, of both types. So, please refrain from drawing any conclusions of optical performance based on these examples. Though the camera bodies were near final, so image noise and other parameters were a good indication of the cameras output."