Sensor are complex device that are design to work within a certain range where all parameters are within their best working range and their base ISO is a compromise.
Going to ISO could reduce the amount of noise at the expense of the dynamic range of other characteristics. For instance the sigma dp1 has a sensor that has a base ISO of It is also possible to use it at ISO Sigma expressively mentioned that despite the lower amount of noise, ISO 50 will also noticeably reduce dynamic range.
I've been reading Steve Simpkin's recommended link. One contributor adding this comment which you may find interesting Ultimately though, they could've added a boost like they do with Hi-1 and Hi-2 but when others had done this Canon 1D the images lost Dynamic Range and Detail so it was best to just stick with what the sensor was designed for". So yes it will do ISO , but only if you don't mind the loss of quality!
It's kind of a health warning "We take no responsibility for the output of this camera below ISO ". I'm genuinely bemused by Nikonians lack of fuss over this issue. Lower ISOs make for finer pics and vice versa.
So for those landscape photographers among us who are prepared to haul a tripod up a mountain to insure we can shoot at the lowest possible ISO, a camera that simply omits this option is a true contradiction as a photographic tool! Equally galling is the loss of exposure control ie shooting at slow shutter speeds on bright sunny days nice with waterfalls, seascapes etc or shooting wide open to throw the background out of focus — a pretty basic requirement actually.
Ironically Nikon are touting one of the benefits of the D90 as its ability to shoot movies with the background out of focus!!!
Wonderful Nikon, but what about us photographers? Lower ISO is good if you need a longer shutterspeed. No-one seems to be complaining about the D's image quality with its base ISO sensor. What's your point? So the Nikon D90 will never produce pics as fine as say the Canon D. However its high ISO may or may not be better than the Canon's. It sounds like the D90 may be good for sports and concert photographers but not a tool for landscape photographers. As someone who does a lot of landscapes I would have preferred Nikon to have prioritized absolute quality, and exposure control, and then seen what they could do about high ISO IQ.
In a landscape work, you use a polarizer with it you loose stops and if you add some ND grad filters to equalize bright sky against dark foreground, you loose again stops. Even is not enough! So, do you carry with you all the time a tripod? For waterfalls you need ND filters ie. Simon65, You mention the rules of physics, yet no references. To speak as if there is a magical value to ISO just shows your lack of perspective, or maybe just trolling. None of us writing so far know the detailed specifications of the sensor substrate, its base amplification and response curves, etc.
Is ISO so much better for you? Your entitled to use it, even if there is no logic in your decision. That's so outdated thinking Besides, in good light almost everyone will stop a little bit to get better sharpness. That's idiotic. Those sensors are optimized to different base sensitivities and base sensitivity is the one which offers ideal performance.
Besides, with today's technology, if you can see difference in quality between dSLRs sensitivities of and you clearly have better vision then superman. I shoot mostly cityscapes with my d Quality and control over exposure is state of the art.
Lower base ISO would give me nothing. High ISO gives me many important things:. Thing is, and I hope someday people will understand this and there will be no more funboys, that with today's technology much much much more depends on how you can use your equipment not what camera you own.
And trying to see some differences in quality at lowest ISOs is extremely funny. Because dSLR sensors are quite large their sensibility to light is higher. The D90 sensor assuming it's the same sensor as D is designed to give its optimal output at ISO dynamic range wise. You can't compare ISO sensitivity between different sensors and say a sensor has less noise because its base ISO is or The reason compact digital cameras have such low base ISO is artificially set, to minimize shadow noise because of the tiny sensors, but the DR is reduced dramatically as a result.
The only problem with a base ISO of , is if you want low shutter speeds in outdoor daylight flash, moving water. Though the D90 has possibility for setting LO 0. Low ISO sensitivities require slow shutter speeds for correct exposure, resulting in blur caused by subject motion. When lighting is poor, you can use a flash to light portrait subjects. Flash units, however, have limited range. If you raise ISO sensitivity, you can optimally expose both the portrait subject and the background without using a flash at all.
Imaging Products. High ISO sensitivity, fast shutter speed. No-Flash Low Light Photography When lighting is poor, you can use a flash to light portrait subjects. Bright lighting, like outdoors in the sunshine, will require a lower ISO setting and therefore gives a cleaner image with less noise. Poor lighting, like in a forest under cloudy skies, would require a higher ISO and typically result in noisier images.
You can always use a tripod though if you want to maintain a low ISO and keep your photos noise free. Using a tripod allows you to use a longer shutter speed to get that precious light to your sensor, rather than having a more sensitive ISO setting. The caveat for this is that your subject must be static, because a long shutter speed will not be able to stop motion.
The world around your subject would be sharp, but it would be blurry. This base ISO will produce the least amount of digital noise. If you are using a point and shoot camera, or a DSLR with liveview, then the aperture setting will usually be displayed somewhere around the extremity of the image on your main LCD. Whilst it is always possible to manually select your ISO, many people also prefer to have the camera choose a suitable setting.
If you are still in the early stages of understanding shutter speed and aperture, using shutter priority and aperture priority exposure modes, then you can certainly simplify things by switching ISO to auto.
Even if you do put ISO into auto mode, you should still be very aware of the purpose and effect that it has on your photos. Increasing your ISO by three stops would allow you to increase your shutter speed by three stops.
Pretty simple right?! Another common reason to increase your ISO is to allow you to shoot with a greater depth of field, perhaps when taking a hand-held landscape photo.
In this case we might increase our ISO by a few stops in order to be able to use a smaller aperture which will give a greater DOF. If you increase your ISO by three stops, you can increase your f-stop by three stops as well and still maintain the same overall exposure. For the most part, people are usually concerned with the usage of higher ISOs, but sometimes you might find that your exposure is requiring an aperture that is too small to get that nice shallow depth of field look for a portrait.
In this case we would want to lower the ISO. Note that unlike f-stop and shutter speed , ISO values are never provided in half-stop increments. Your camera will either allow you to choose ISO in one-stop, or third-stop increments. We now know what ISO is and how it affects the noise in our image for a particular camera.
Generally speaking, the more room a pixel on your sensor has around it, the less noise is generated in your image.
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