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What camera(s) do you own?

What camera(s) do you own?


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Trevor

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As far as noise goes: I find it to be better with cmos sensors in dark conditions, but worse in fully lit ones. It's by no means terrible, but if you take a picture in brought daylight (iso 100, f/8, 1/500s) the cmos sensor produces some noise in, for example, the blue of the sky.
I think my knowledge of CMOS vs. CCD's in the context of P&S cameras is limited by the fact that nowadays I don't take note of anything but full-frame PJ/sports bodies. :eek:

Here's an image shot with a Canon S90 (which has a CCD sensor) that produces grain in the blue sky:

http://www.dcresource.com/sites/default/files/galleries/canon-powershot-s90-photo-gallery/IMG_0298.JPG

I think it's more of a pixel size issue than a CMOS vs. CCD issue.

The Canon S90 has a sensor in it with an area of 43.3 square millimeters, compared to 864 square millimeters of a full frame camera. That's like cramming 200MP onto a full frame sensor! That's a LOT of pixels... SMALL pixels.

Then, beyond that, you have a Bayer filter over the sensor. In a CCD or CMOS (as opposed to film or that Foveon nonsense) sensor, each photosite can only read one color. Check out the image below:



As you can see, all color elements arrive at each photosite, but only one channel is allowed to hit the sensor. This leaves you with a three component tiled pattern: 50% green (green + luminance), 25% red, and 25% blue. Each final pixel you see in your JPG or RAW file is the product of a processed called demosaicing where the Bayer mosaic is processed and a final image pixel is generated from sampling at the nexus of four of the photosites - 2 green, 1 red, and 1 blue.

So, when you take a photo of something that appears so uniform, you're going to run into grain in a P&S for two reasons:

  1. There are only so many photons to go around. In a given time, one pixel might see more blue photons than another. When your pixels are so small, this problem is compounded.
  2. Only 1/4 of the pixels on your sensor even pay attention to blue light - plus the green pixels which will also see uneven distribution.

    When you consider both of those limitations, the presence of a grain pattern in something like a blue sky isn't really all that surprising.

    I'm not sure why the iso value cannot be lowered below 100 (even when set to auto) on this camera though - it could be a technical limitation of the sensor design.
    Base ISO is basically just reading the values off the sensor without amplification.

    My 1DX will do ISO 100 - 51,200. So, if you bumped the base ISO down to 25 and used the same amplification hardware, you'd lose two stops at the high end of the ISO range. So the final range would be 25 - 12,800. If you kept 51,200 as the high, it would end up being overwhelmed by read noise.

    If you want to shoot in bright light with a fast lens, ISO 100 and a shutterspeed of up to 1/8,000 is typically just fine. A friend of mine rented an 85 f/1.2 and we took it out to shoot in broad daylight - I could usually get away with a high shutterspeed. But when I couldn't, my friend had ND filters on-hand - because when your bag doesn't contain any sub-$1,000 lenses, not spending some money on a few nice ND filters is pretty inexcusable.

    Some camera bodies offer an "L" mode (just like "H" ISO modes) where the image is digitally brought down, but most people don't bother with that for the above reasons - and on grounds that it is digital, not analog.

    Trevor
 
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Benm

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Perhaps manufacturers change the base value of the iso unit, i'm not really sure. The panasonic did lower the iso value below 100 in program mode (down to 30 or so in bright light), the canon will not drop below 100 if you'd try to take a macro of a car headlight.

As for the bayer filter pattern: that is also a matter of processing. If you were to take any 2x2 pixel block you can gather from that:

4 pixels for luminance, but all the same chroma.

For a 4x4 pixel block, it would be 4x4=16 pixels luma, 2x2=4 pixels chroma

Basically that is what the firmware should make out of it, and this suits the JPEG compression algorithm very well too. Perhaps luma noice actual results in chorma noise in the sky making it that visible due to the algorithm used. Unfortunately these compacts only offer JPEG shooting, so there is little to tinker with.
 

Blaster

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samsung S4 for a mobile phone camera its brillant no need for dedicated camera
 

bofhemeritus

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Nikon D7000, 105mm/2.0 macro, 200mm/4.0 macro, 75-200mm zoom, fisheye that I don't remember - and a big handful of filters.
 

Ears and Eggs

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Right now I just have my HTC Desire smartphone. :( I used to have a Canon Powershot A570, but it broke and I couldn't fix it. :(

I finally got a new camera, a GE J1456W. Nothing special, but a heck of a lot better than my HTC Desire's camera. :)



 

Pi R Squared

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I have a Nikon Coolpix 800, its a few years old but still takes great pictures, very good optics, I hope Nikon is still making such high quality cameras.

Android phone LG Optimus V, its OK but takes grainy pictures unless the light is very bright.

And an iPad 3, much better than the LG and higher resolution than the Nikon but can't match the Nikon for some things, its lacking features and who wants to carry around an iPad for taking pictures.
 

Benm

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Camera's in phones should not even be listed as such. Surely they produce digital images, often with an impressive number of megapixels, but consideringen in tiny lens they simply cannot perform well unless you are in a brightly lit environment.

That said, my ixus 310hs recently got damaged and the lens shutter will hardly open - any suggestions for good compacts that are about the same size and price ($300 or so) that would make a suitable replacement? 25mm or lower wide angle is a requirement, as is a couple of times of optical zoom, though 4 to 5 times is enough for me and something like 10 or 20 times otpical zoom has little benefit for me.
 

Bionic-Badger

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Recently bought a Canon EOS M, a micro 4/3rds camera with an APS-C sensor. These are going for fire-sale prices, but with the latest firmware the major defect (slow autofocus) that torpedoed the price has been fixed. This camera is awesome, and even if I get something to replace it, I can have it converted for IR or something and it'll be great.
 
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DJNY

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CANON EOS 5D -Q.M.- // CANON EOS 100D

...............................----with----

CANON... ..15 mm f/2.8 | 17-35 mm f/2.8 | 18-55 mm f/3.5-5.6 STM | 80-200 mm f/2.8 | 85 mm f/1.8 | 200 mm f/2.8
TAMRON.. 24-70 mm f/2.8
SIGMA..... 50 mm f/1.4
 
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Blarg King

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I have a Canon SX130IS. Its about 2 years old now but its still one of the most feature rich "point-and-shoot" type cameras out there. Looking to get a Nikon D3200 whenever I have money in the future.
 

Operator

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I own:
Pentax K110D
Pentax K1000
Pentax ME Super SE
18-55, 50mm f/1.7, 50mm f/2 (x2), 70-300
Nice to see another Pentax guy!!!!

My gear:
Pentax K-5
Pentax 18-55mm F3.5-5.6 AL Kit Lens
Pentax 28-200mm F3.8-5.6 AL [IF]
Pentax 35-80mm F4-5.6
Pentax 75-300mm/4.5-5.8 FA J AF
Sigma 10-20mm F4-5.6 EX DC J
Focal 28mm f/2.8
Vivitar MC 28mm f2.8
 

Operator

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Though to be honest, I probably use my iPhone more often, as it's just about always with me. Also use a Drift720 and GoPro for videos, but I guess they are also cameras?!?
 




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