This article was originally written on Oct. 5, 2011, following the announcement of the new iPhone 4s. Remember, many people claimed to be underwhelmed by the features of this new iPhone which then proceeded to sell like ice cream on a sunny beach. Contrast that with the recent announcement of the iPhone 5. Again reviewers are underwhelmed, yet the order lines are overwhelmed. Watching close to see Apple in the post-Jobs era. Will they continue to succeed like peanut butter on bread. For me, since I have the old 3Gs, I'm very interested in this new iPhone 5 ... if, for nothing else, for the camera. Plus 4G cell coverage is good.
The recent announcement of the new Apple iPhone 4s held
excitement and some disappointment to various Apple fans. One comment I
read in response to the disappointment people that said, “outside had
not changed” is a comparison to the Porsche 911. It’s outside hasn’t
changed much over the years either, but -- as they say -- it’s what’s
under the hood (or, if you’re English, the bonnet) that matters.
Let’s
talk about under the hood, specifically the new camera in the iPhone
4s. I’ve been a camera buff, a shutter bug, a photography want-to-be
since about the sixth grade. I recently purchased a replica of my first
two cameras on eBay, and I’m working on a historical reference article
about all the cameras I’ve ever owned. Expect to be bored out of your
seats when that movie hits the theaters, but, for now, let’s talk about
the iPhone camera.
I’m a big believer that the best camera
is the one in your hand, yet I personally own and carry a flotilla of
cameras, each tuned to a particular use. I’ve got a big (and heavy and
clunky) DSLR with more glass than a picture window, plus a nice little
camera that is probably the most advanced “point and shot” every made by
Canon. I supplement that with a Nikon super zoom camera, a tiny Canon
that I’ve hacked the software on, and a small “viewfinder” digital
camera with interchangeable lenses from Olympus. I also own a plethora
of video cameras from a Flip to a Sony, to a Canon handicam to a large
JVC and a Professional Canon XL2.
I do use my current
iPhone camera on occasion, but mostly to take pictures of wireless
router labels to capture the SSID and Passcode. My brother-in-law,
Chuck, on the other hand, takes tons of excellent pictures with just his
little old iPhone. He usually gets up close and personal, since the
phone lacks a zoom lens, and it is really quite a good camera in the
iPhone 4, but still -- it is a phone after all, and typically phone
cameras lack many of the basic functions and features found even in the
cheapest point and shoot cameras. All that said, Chuck takes really
excellent pictures in all kinds of light with his iPhone 4. How much
better can it get?
Well, let’s look in detail at the new camera under the hood of the iPhone 4s.
The
4s camera gives you 8 megapixels -- that’s 60 percent more pixels than
the camera on iPhone 4, and the older iPhone was quite good in the pixel
department. The advantage of the increase is self-explanatory, but
really the least important part of the upgrade. In general, the pixel
race is really over and even somewhat self destructive. Other phones and
small cameras have high megapixel counts, and, really, you don’t want
or need that many. The thing is all those tiny pixel have to be packed
into such a small place that you end up with image quality problems.
(Sure, the top of the line DSLR cameras are up in the 12 - 18 - 24
megapixels range, but those are on much, much larger sensors.)
In
the case of the iPhone incremental pixel increase, I expect your best
photos will look better and it probably won’t affect any shots
negatively. But I think it is just the icing on the cake. Wait until you
hear about the cake!
As an aside, the primary advantage
of high pixels is that you can enlarge the picture to a bigger format
without becoming grainy or “pixelated.” Maybe more important is that
lots of pixels means you can crop the photo and frame on a small
section. That is sometimes called “digital zoom.” That is important
since no phone camera has optical zoom. There just isn’t room for a
complicated, motor driven zoom lens. Eight megapixels is nice and
catches up to some of the competition smart phones, but, as I said,
cramming more pixels into a small sensor can actually reduce photo
quality due to increased noise and loss of individual sensor
sensitivity. Along with the higher bit resolution, the iPhone 4s has
gone to 1080p video resolution. That’s nice, but all the earlier caveats
still apply.
Now, the cake: what really excites me is the
changes in the lens and the camera light sensitivity. The biggest
achievement has to be with the lens, which is said to let in 73 percent
more light. Moonlight and candles may now be enough! And that is good
since camera phones don’t really shine in the flash department either.
(Get it? Shine!!)
Action shots should be less blurry too,
since higher sensitivity means faster shutter speeds, but we will not
know how much truth there is in that statement until we get our hands on
one --and that must wait until pre-order delivery day.
How
was this done? Well, let’s get technical for a moment. In any camera,
phone, video, still, film -- any camera with a lens, the key is the
amount of light gathered. The more light the lens lets in, the better
the performance under lower light conditions. This “size” of the lens is
measured in a technical specification called F-stop. This is a ratio
between the diameter of the aperture in the lens and the focal length of
the lens. If the ratio is 1, then that is one big and “fast” lens. (I
won’t explain the fast part here. You’ll have to wait for the movie.)
Basically, the bigger around the lens for a given sensor size, the more
light that is let in. Kind of like the bigger the bucket, the more water
you can carry.
It is an advantage of having a small
sensor that you can then use a small lens and get good light. Bigger
sensors require bigger lenses for the same F-stop and bigger is heavier,
larger, and more expensive. But, again, the best cameras have large
sensors and large individual pixel sensors and ... well, let’s leave
that idea for now too. (Before we go on, I should explain that the
bigger the lens aperture the lower the F-stop number ... that’s just to
confuse you all ... so, is that working?)
The new iPhone
camera has a five element lens, including a filter to block infra-red
light from saturating the sensor, and the lens is F/2.4. That will let
in about twice the light of the previous iPhone’s F/2.8 lens. More
elements means better quality in terms of bending the light and focusing
it on the sensor without color separation or blurriness of “spherical
aberrations.” (Don’t you just love it when I talk that way?)
The
most important part of a camera is… the photographer — but next in
importance is the lens. And the lens of the iPhone 4 was already pretty
solid for a camera phone: F/2.8 (apparently limited to F/3) at about
30mm equivalent focal length. The new one is F/2.4, about half a stop
better, which doesn’t sound like much, but at this point of the aperture
scale counts for a lot.
It’s a pretty big increase in the
total amount of light hitting the sensor. The focal length wasn’t
specified by Apple, but in its announcement they mentioned it was “super
wide.” Which, if wider than 30mm equivalent, starts putting the iPhone
into true wide-angle territory (starts around 24mm equivalent if you ask
me) -- but that may have been referring to the aperture. At any rate
the half-stop improvement is real enough.
(The advantage
of limiting a lens to a slightly higher F-stop is that the outer portion
of any lens has more aberrations or “blurriness” than the center
portions. That is a reason that professional photographers often stop
the lens down a step or two to improve the quality of the image.
Starting with a lower number F-stop helps that too. Also, F-stop affects
depth of field. But, again, we won’t get into that here either.)
There
are other factors at play here too. One is the “shutter speed.” In DSLR
and other high cost digital cameras and all film cameras there is an
actual shutter. But in point and shoot and phone cameras the shutter is
simulated by the time it takes to scan and read the digital sensor. The
faster A5 processor gives that higher speed to the new iPhone 4s and
should lead to less blurry photos. That also helps with the higher video
resolution and progressive scanning.
Speaking of the new
and faster A5 processor, it is part of the overall equation too. The new
system was described by Apple as being “1/3rd faster” than the previous
iPhone, which is a phenomenally vague description, but I’m guessing the
onboard electronics are able to offload the image data 30% faster. But
with these small sensors, what matters isn’t getting the image off the
sensor, but getting it processed, encoded, and displayed to the user.
The A5 processor has a major focus (“focus,” get it?) on graphics
enhancement. Having a chunk of the CPU entirely dedicated to JPEG
processing is a given. So the combination of a faster sensor and an
expedited pipeline for that image data to go through makes the iPhone 4s
camera twice as fast as the competition at making the shot happen. It
also allows for more accurate white balancing and color tweaking, so
your shots won’t look like they were taken with a red heat lamp or under
a blue sun.
The new sensor even has another trick up its
sleeve. In previous digital photo sensors, the actual light sensitive
material was on the bottom and over the top were the interconnecting
“wires” that hooked it all together. The “so-called” backside
illumination sensor basically flips the sensor over so light strikes the
light sensitive bits without having to navigate a forest of circuitry.
This improves light sensitivity.
This iPhone has one of
the new “next-generation backside illumination” sensors. An upgrade to
the upgraded sensor that made the original iPhone 4 camera much better. I
won’t know for sure who makes the camera until the teardown comes, but
Omnivision did the last one and they have a newer version called the
OV8812 with the exact resolution specified by Apple in this new phone.
The improved sensitivity probably isn’t as impressive as the jump from
3GS to iPhone 4, but better low light performance is always welcome.
Why
Apple even added real-time stabilization. This is a nice feature for
small cameras, since, lacking heft, they tend to wiggle around a lot.
Besides, I have shaky hands. (Me and Neil Young.) I’m assuming it’s not
optical stabilization, since that would require more space than they’ve
got, so it must be electronic stabilization based on live image
analysis. Again this is the A5 at work. By designing the camera’s image
processor around the hardware (and vice versa), Apple can do this kind
of heavy graphical analysis without taxing the battery too much.
(Another improvement is that you can now press the “volume” button to
take a picture rather than the “shaky” press on the touch screen. Apple
just puts it all together -- don’t you think?)
As usual
from Apple, and what I’ve grown to expect, the balance of hardware and
software is nearly optimum in the latest iPhone. The camera is so good
that even I may start using it for more than just “honey did you bring
the camera to take a picture tonight” response. After all, the most
important part of all cameras is the person standing behind it and it is
a poor workman who blames their tools, but I think Apple has really put
a powerful photographic tool in this version of iPhone. It just keeps
getting better. I can hardly wait for next year, but I’m not waiting ...
“hello, Apple, just checking on the status of my pre-order."
Sunday, September 16, 2012
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Yes,the Iphone 4 has a 5-megapixel camera with Flash, HDR support and HD video recording. In other words the device can offer you some great pictures while on the go, not to mention videos. But sometimes its camera stop working and freeze your phone then I start searching remedy for that trouble and I found solution at http://howmobile.net/apple-iphone/2853-solution-camera-issues-iphone.html. Hope you can like the solution. It’s very easy to understand. Hope the solutions solve your Iphone 4s camera trouble.
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