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New Ceramic Lensed Exilim Ex-S100
stuart miles writes "pocket-lint has managed to be the first to review the new ex-s100 3mega pixel from Casio that uses a ceramic lens rather than the standard glass version.
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I don't understand this either:
"The bad:
Only 3.2 megapixels, no SD card in the box"
No SD card in the box is a GOOD thing, who uses wimpy 8-16MB cards that come with the camera? SInce the Casio Exilim line has builtin memory (10-20MB), there is no sense in including small SD card.
Yeah, ceremics can be transperent. It's harder for cermics to be, however, seeing as it's just a bunch of (transparent?) granules smushed together under high heat.
Optical quality (and price) general go as the following:
Cermics
Amorphous Solid (glass)
Single Crystal
The more "regular" the structure (the less interface bounderies and material gradients) the better the optical qualities are.
There is also a review in Steve Digicams. I like their reviews because they also include some sample pictures you can use to compare to other cameras (of course the pictures are taken of the same buildings, etc. but they differe in light available. The sample pictures are still good).
I don't see how they were the first, when Steve's Digicam's has a review for this exact model dated two weeks ago. It's a much better and more thorough review as well, IMHO.
I paid less for my nikon 4mp camera. Sure this is a smaller camera but smaller is not always better. I already feel like I'm going to break my current one and it's huuge next to this one.
There's a much better review at Steves Digicams
Might want to check that one out too.
Do not anger the worm.
The more pixels a digital camera has on its CCD sensor, the larger the pictures you can take. The following is a list of the maximum size an image may be (measured by height x width) for the three most popular types of digital cameras on the market today. * 2-megapixel digital cameras - 1600x1200 * 3-megapixel digital cameras - 2048x1536 * 4-megapixel digital cameras - 2272 x 1704
Linux is like living in a teepee. No Windows, no Gates, Apache in house.
Save yourself some time and jump to the full review, the verdict, or the reader reviews--doesn't look like readers agree with the 9/10 rating.
In a nutshell, the transparent ceramic lens can be thinner and lighter than a glass lens because it has a higher refractice index (bends light more). It's also stronger, they say. Nifty, just what you need to make a smaller camera. Of course, if you put that tiny lens in front of lousy electronics, you get a lousy camera. As another post mentioned, the review said there was a lot of noise, which sounds like a lousy camera to me.
See what I've been reading.
dpreview had a press release from Casio a few weeks ago..
... higher refractive index than glass. [snip]... thinner and stronger than conventional glass. ..[snip] reduction in the profile of a lens system by approximately 20%.
Highlights:
August 02, 2004, TOKYO, JAPAN - Using its proprietary optical technology, CASIO COMPUTER CO., LTD. has developed the world's first lens using transparent ceramics. This breakthrough will make it possible to create zoom lenses for cameras with greatly reduced profiles.
There are soom cool pictures of the lenses as well as some text and graphics that explain what is going on pretty well.
http://www.busyweather.com/
Just would like to point out how silly all of this ceramic vs. glass business is, since glass is considered a ceramic! And, "ceramics" encompasses quite a lot of materials. You really have to take announcements like this with a grain of salt, and realize that while it may be better, it is also a gimmick when they say something like new "ceramic" lens! Oh yeah, and I'm a ceramic engineer...
Oddly enough, Steel with 6.67% bw Carbon is Iron Carbide, a ceramic. According to my material science book, Ceramics are compounds of metallic and nonmetallic elelments. Ionic or Covalent bonds form which are stronger than metallic bonds.
Glass is an amorphous solid, a liquid that is cooled at a rate too high to allow crystals to form. Glass ceramics have a high crystalline component to their microstructure. As a result the hardness of a glass ceramic comes to a higher level.
And yes, I am a Mechanical Engineering student. (Who should be typing a lab report for his material science class right now)
Bacardi + slashdot = negative karma.
Because of their memory effect, NiMH are the most inconvenient batteries to use.
NiMH have very little 'memory effect' - NiCd's are the offenders there. However, all batteries need to be treated correctly - I keep my batteries in sets and don't mix the batteries within those sets, that way I never end up mixing fully charged batteries with semi-charged, etc (which really does kill batteries).
NiMH cell capacities are now on-par with Alkalines, the only downside of NiMH cells is that they do discharge over time.
Whilest Li-ion's have a higher energy density, they are also not compatable with alkaline batteries, and when I'm on holiday and stuck with a dead battery I'd prefer to have the option to buy some alkalines from the shop rather than do without my camera.
(I have a HP Photosmart 850 and am _very_ happy with it)
http://blog.nexusuk.org
As the other ceramic engineer pointed out, glass is considered a ceramic. What makes it good for lenses is the fact that it is amorphous, i.e. has no periodic crystal structure. Thus, light will pass through it without being refracted in strange ways because on a macroscopic level, all the glass is the "same" (or the heterogeneity is small enough and distributed evenly and randomly).
Now, I didn't read the article, though I wouldn't expect it to get into details. I assume by "ceramic" they mean "crystalline ceramic" (versus amorphous). When you make crystalline ceramics, you don't typically make one continuous crystal (like a polished gemstone), but many small (10 to 500 micron is typical) crystals (grains) surrounded by very thin amorphous regions (grain boundaries). Grain boundaries serve to refract the light (I suppose they are much larger and thus less heterogenous than anomalies in the amorphous glass), which is why ceramics (think dinner plate) are opaque. I'm getting to the limits of my [limited] knowledge, but I believe the only real way to make transparent crystalline ceramics is to use a single crystal which contains no grain boundaries. This tends to be costly due to the need to melt the material to coax it into a single crystal and the high melting temperatures of ceramics (see silicon industry).
Given that, I'm not sure why using a single crystal lens would have an advantage over an amorphous glass lens... Perhaps you can achieve a higher index of refraction.
There's another way to make polycrystalline (as opposed to single crystals) ceramics transparent: Make the grains smaller than the wavelength of light you're trying to transmit, eliminate porosity completely, and eliminate the sintering aids that go to the grain boundaries and fudge up the refractive index there.
Transparent polycrystalline alumina (not aluminum) has been in regular use for 40+ years. It's called Lucalox by GE and is the refractory material that makes up the tube used to hold the molten sodium in all those yellow/orange sodium streetlamps.
I'm assuming this is what the camera lens is made of, but have nothing to back that up with.
As a side note, you may have noticed that every few years someone publishes a paper on a new way to make transparent polycrystalline alumina, then the non-materials-science media (*cough slashdot*) catches wind and assumes alumina is the same thing as aluminum, and suddenly the prophecy of transparent aluminum from Star Trek IV has come true. It's sort of a running joke in the materials science community.