As Apple stuff more features into each new iPhone, some of the functions get hidden or streamlined. One of these features is Facetime, Apple’s video chat service. As of iOS5, there is no icon for facetime anymore, instead you initiate a call much like you do a phone call. You have to find the person you want to Facetime on your contact list, scroll to the bottom of their contact card, and then hit the “Facetime” button.

The iPhone OS has gone through five major revisions – each one comes with more and more features. However, the simplified interface that made the iPhone so successful also means that it’s sometimes hard to get to the more advanced features unless you know what you are looking for. iOS 5 includes some completely hidden features that you may not know about. This will be the first in a series of tips that show off some of the newer or hidden features in iOS 5.

You can now access the camera app quickly from your lock screen. Press the home button twice when your phone is locked, and you will see a “camera” button appear near the lock slider. Pressing this button brings you immediately to the camera app. No need to unlock the phone, find the camera app, and press the button.

Remember, you can now use the “volume up” button on the side of the phone to take a picture.

You may have noticed that the iPod controls also show up when you double-click the home button – allowing you to play/stop/forward/reverse through the current playlist. Great for when you’re on the go.

The J1 is the cheaper mirrorless camera Nikon introduced last month, and it’s first foray into that market. Engadget posted their review but the summary below is probably a good thing to read if you are considering buying it:

If image quality is more important than looks, advanced photographers will probably want to search elsewhere. $650 is a lot to spend on any camera, and when you consider that Sony’s NEX-C3 is selling for the exact same price (and is available now), that has been, and still remains, our first choice. The C3 excels in nearly every area — pro-level control, color and exposure accuracy, and overall image quality — though the J1 does offer a few unique and clever features, including slow-motion shooting and Motion Snapshot, along with that silent shutter. So does that make this camera a close second? Sadly, not by a long shot. That title would go to the Olympus E-P3, which offers class-leading focus speeds and consistent performance. Nikon’s new ILC is more class competitive with, say, the novice-friendly Panasonic GF-3 or Pentax’s Q (though we haven’t yet had a chance to thoroughly test the latter).

Olympus is giving away 1000 E-PM1 cameras – this is the same camera I’ve been blogging about for the past two weeks. It’s the most economical mirrorless camera out there and features the most up-to-date 4/3rds sensor. It should arrive in stores soon but 100 people in Toronto got the camera when the Olympus team was promoting the PEN Ready campaign.

Small sensors aren’t good. They require a higher pixel density for the same picture quality, or offer a lower picture quality compared to larger sensors. Here is now Nikon’s “System 1″ sensors stack up to the competition:

SLR sensor sizes:
full frame: 36 x 24mm
canon DSLR 1.6x crop: 22.3 x 14.9 mm
nikon DSLR 1.5x crop: 23.6 x 15.7 mm

mirrorless sensor sizes:
sony mirrorless 1.5 crop: 23.5 x 15.6 mm
four thirds 2x crop: 17.3 x 13 mm
nikon 1 2.7x crop (CX): 13.2mm x 8.8mm

point and shoot sensor sizes:
canon s100: 7.49 x 5.52 mm
panny lx5: 7.89 x 5.81 mm
canon hs100: 6.17 x 4.55 mm

While larger than point-and-shoot sensors, it is the smallest, by far, of the mirrorless sensor sizes. Disappointing.

It’s important to note that Sony’s mirrorless system uses sensors as large as the common DSLR sensors (1.5x crop factor). That’s great – however Sony’s prices are high enough that it competes directly to full DSLRs.

The sweet spot is Olympus’ upcoming E-PM1 (aka the PEN mini). At $500 which includes a lens and an external flash, it’s a great deal. It also is the smallest and cheapest mirrorless camera.

Update: I found the new CX sensor size documented on wikipedia:

Nikon introduced their mirrorless camera system today at midnight. The J1 and V1 are 10MP, 2.7x crop factor cameras using a new interchangable lens system. Honestly, even as a Nikon shooter, the specs leave me very disappointed. First, the price, is far higher than most mirrorless systems from Sony, Panasonic and Olympus – especially given Olympus’ new E-PM1 that is $500 incl. lens. Moreover, the sensor is very disappointing – the very high crop factor (meaning a very small sensor) won’t impress anyone, especially Sony who uses a full APS-C sized sensor in their flagship mirrorless camera. The sensor also has a max ISO of 3200, well below every single mirrorless offering out there. I do not expect strong sales of these cameras – it is a baby step intended to protect their DSLR investment, nothing more.

I’ve posted a lot about the high-end point-and-shoot cameras before, this market had some great offerings in the past two years. However, a tipping point in the market has been reached and many companies are fighting it out in the mirrorless interchangable lens camera space. Featuring larger, better sensors than point-and-shoot cameras, these systems also feature interchangable lenses. They’re generally smaller than SLR cameras because of the lack of a TTL viewfinder and it’s required optics. Lens quality is not as good as full SLR lenses, but you get a much smaller form factor. These mirrorless cameras take photos with picture quality rivaling dSLR offerings just one year ago.

While these cameras have been out for a while, this summer an explosion of offerings of mirrorless cameras have been announced. Instead of just “high-end” mirrorless offerings, there are not multiple offerings at different price points. The Olympus PEN E-PM1 is rumored to list for $500 – and probably will sell for less at retail assuming there is an adequate supply. The PM1 is the camera I am considering. Now is probably the best time to consider these cameras if upgrading from a point-and-shoot or looking to complement a dSLR.

Olympus PEN E-P3

Olympus PEN E-PL3

Olympus PEN E-PM1

Panasonic DMC-G3

Panasonic DMC-GF3

Samsung NX200

Sony NEX-C3

Sony NEX-7

Sony NEX-5N

Some people might consider the Fuji X100 and X10 to be comparable, however that camera does not have interchangeable lenses, a very strict limitation for a $1000 “point-and-shoot”.

Olympus just announced pricing for it’s latest PEN 4/3 camera. At only $500 (USD) the PEN E-PM1 will be the cheapest 4/3 camera out there. It is still compatible with all of Olympus’ lenses and is in a nice, small form factor. At this price point, the PEN Mini, as it’s called, is right in the reach of shooters looking at the Canon S95 and LUMIX LX5. With it’s larger sensor, interchangable lenses and RAW capability, it will far outclass those cameras at the same price.

Drawbacks? There is no flash, but a good f1.8 prime lens should fix that, and Olympus sells one.

I’ve been itching to get a mirrorless camera as my secondary. Nikon and Canon still have not announced theirs yet, and I think this Olympus at this fantastic price point will do it. Can’t wait until September!

Sony just announced their latest flagship SLR camera. It shoots an impressive 12fps with a 24MP sensor and features an articulated OLED viewfinder in the back. DPreview covers the announcement and has a hands-on preview.