This is a fact. We cool our sensors on the camera down with liquid nitrogen. It works a peach.
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Noise, Noise, Noise!
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This is a fact. We cool our sensors on the camera down with liquid nitrogen. It works a peach.
A fellow physicist, I reckon *This is a fact. We cool our sensors on the camera down with liquid nitrogen. It works a peach.
Yeah, I've been to a lab, all CCDs are cooled with liquid nitrogen.
Flashback: a picture from 2004 (straight from the camera, I've cropped and straightened it, and increased the saturation just a little), click on the pic for a full-res version. Have a look at the sign on the top-center: lots of chroma noise. The pics were taken in the early evening/late afternoon at ISO210 with an Olympus C-4040 (not a bad camera at that time). I still love the pic …*can you guess who the guy is and what he is doing?
If you disallow post production then you options are very limited. About all you can do is shoot at low ISO.
To allow shooting at low ISO then either (1) there is a lot of natural light or (2) You spend the bucks for some fast lenses or (3) you bring some lights (strobes, hot lights or whatever) with you or (4) you use a tripod to allow longer exposure but then this does not work if the subject is moving. For best results you combine as many of the above as you can. Notice that all of this advice would have applied 50 years ago -- nothing special about digital.
We say "noise" but really what we mean is "signal to noise ratio". The noise is always present but some times there is more "signal". In other words the root cause of noise is lack of light hitting the sensor. You get better quality (with digital or film) if you can put more light on the subject. Look at any professional in the studio and you'll see that they've invested maybe even more money in lights than in cameras. They are putting their money where it matters.
A fellow physicist, I reckon *
Yeah, I've been to a lab, all CCDs are cooled with liquid nitrogen.
That only address thermal photons which dominate the noise at long exposures. But if we are talking about fast exposures (as in hand held snapshots) then I think the noise we see do to the statistics of small numbers (of photons) and cooling can't help.
In a digital camera all the ISO setting does is adjust the gain on an amplifier there is no way to adjust the sensitivity of the sensor, so at ISO800 you are just multiplying a small signal and of course yo see noise.
My comment was a bit tongue-in-cheek, since I was referring to the thermal imaging systems that we make at work. Those are generally cooled to LN2 temperatures or lower. It really wasn't as on-topic as you might have thought before.
I was joking. Of course you can't break the laws of physics and you cool ccds and other equipment (e. g. signal amplifiers) down to quench thermal noise. Thermal noise is even used to measure very low temperatures.
Some expensive digibacks are actively cooled for that reason (I think the digiback for the Hasselblad H3D is one of them).
I often think that noise found on your images is better handled by using applications such as noise ninja or the likes. Under exposing to compensate for the noise usually results in more noise when you adjust exposure. In comparison of the two the noise from a properly exposed image from the camera seems to be better (if I can use that word) than the characteristics of the noise from an under exposed image and then adjusted on the computer.
It is a matter of opinion without any real scientific approach behind such statement.
You could always get a Fuji S5 Pro (exactly a Nikon D200 with Fuji chip) and the noise problem will be greatly reduced. You'll still have ugly multi-colored noise but there will be less of it.
I can't, I really can't. The display on the camera is so F**Ked up, I can't tell exactly what the picture looks like until I get them home.
that's what the histogram is for. you can't trust the lcd screen (it's not messed up - it's just that it is using light to illuminate the screen. it will always be brighter than your exposure. you can turn down the screen brightness to help a bit but always trust your histogram
Flashback: a picture from 2004 (straight from the camera, I've cropped and straightened it, and increased the saturation just a little), click on the pic for a full-res version. Have a look at the sign on the top-center: lots of chroma noise. The pics were taken in the early evening/late afternoon at ISO210 with an Olympus C-4040 (not a bad camera at that time). I still love the pic *can you guess who the guy is and what he is doing?
color noise is a fairly easy fix in photoshop. use Blur>Gaussian Blur (i used 8 pixels on your pic). then immediately go to Edit>Fade Gaussian Blur and change the pulldown from Normal to Color. this forces the blur to only affect the color and not the luminosity of the image
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I use NeatImage Pro and it takes care of my noise problems. I too use a D200 and above ISO 800 noise is a problem, I don't care what anyone says about how great the D200 is. The fact is, the D200's noise handling isn't that great, especially when you hit 1600 and heaven forbid, higher than that. Don't get me wrong, the D200 is a fine camera and a very good value at it's price. I love mine, but Canon's kung fu at higher ISO is superior. Just a fact.
Expose correctly to minimize noise, as has been said. Neat Image does it for me, and very nicely. Well worth the 58.00 price of admission. You can always take the cheap route and create a few duplicate layers. Start with 100% opacity on the bottom layer, then 75%, 50% and 25%. Add about 2% Gaussian blur to the semi-transparent layers. Results will vary.
Also don't apply any other filters, especially sharpening until after you've done your noise reduction work or you're just sharpening the artifacts. Common sense yes, but for the fresh new folks this is an important concept.
edit> oh and yes a monopod or other support is a good thing in low light where your shutters are sub 100- but then if you can afford to shoot at low enough shutters to require support (i.e. little or no motion going on) you could probably get away with lower ISO's in the first place.
I'm just getting this site up so I don't have many of my photos up yet, but this whole gallery was shot at ISO 600 or above, most of it 800+ and I ran neat image on it. There may be a couple of shots I didn't do NR on, but they were all God awful in terms of noise.
Expose correctly to minimize noise, as has been said. Neat Image does it for me, and very nicely. Well worth the 58.00 price of admission. You can always take the cheap route and create a few duplicate layers. Start with 100% opacity on the bottom layer, then 75%, 50% and 25%. Add about 2% Gaussian blur to the semi-transparent layers. Results will vary.
Also don't apply any other filters, especially sharpening until after you've done your noise reduction work or you're just sharpening the artifacts. Common sense yes, but for the fresh new folks this is an important concept.
edit> oh and yes a monopod or other support is a good thing in low light where your shutters are sub 100- but then if you can afford to shoot at low enough shutters to require support (i.e. little or no motion going on) you could probably get away with lower ISO's in the first place.
I'm just getting this site up so I don't have many of my photos up yet, but this whole gallery was shot at ISO 600 or above, most of it 800+ and I ran neat image on it. There may be a couple of shots I didn't do NR on, but they were all God awful in terms of noise.
Thanks for the advice, I'll give it a try
Perhaps Pixelmator will allow for this, too *
What I was getting at, though, was that even a `good' camera a few years ago was a lot, lot noisier than anything you can buy these days.
This will sound like I'm trying to be cute, and talk trash to all the Nikon guys in the thread - but I'm not.
I shoot with 5D cameras, and noise just isn't something I worry about. I don't hesitate in the least to turn to 1600 in a super dark church. I've gone to 3200 and sold 12x18 prints before from the files, that looked great.
I obviously go as low as possible, but with my cameras I fear no ISO!
I shot with a D2hs, D200 and D2x and I fear no noise either. I have sold shots at 20x30 from my D2h and D200 and I have never had a problem with noise. I guess it isn't a camera thing as it is a photographer thing. Besides, for the price of a 5D I can get 2 D200s that are a bit faster and more robust.
I'm confused... OK, you've got a fancy new digital SLR, but that doesn't mean you can rewrite the photographic rulebook. Shooting at high ISO should be the last resort, when nothing else is possible. It's simply not good photographic practice, and the results will be disappointing. And don't necessarily try to solve the problem by spending $$ on a faster lens. Buy a tripod instead, for a fraction of the price, and help yourself to any speed/f/stop combination...
You got it but not yet. For most shooters, taking an image at any ISO as long as you get the shot is what matters. Good images with ample lighting and/or exposures will lend a good image. Getting a tripod for long exposures helps, but having glass with a fast aperture is the other method to being able to bump your ISO down a stop or two. No matter what though... get the shot. Even if you have to shoot a 1600 or up.
The myth that Nikon cameras have noise issues at ISO 800 and up is due to bad shooting. I would love to shoot with a 1D Mk II (the only camera in Canon's line up that makes sense) but the job give me the just as good D2xs, D200s, D2hs and so forth. A D2x image at ISO 1000 give me little noise, because myself and many at my job can expose images properly.
All that really matters is knowing the limitations of your tool (camera) and compensating for that. Don't take your 30D or D80 to a football game with a kit lens, sit in the nose bleed seats, and try to capture a players face, it just won't work.
Properly exposed photos at ISO xxx will lend good photos. It's just a matter of how you shoot.