ISO and bracketing?? D90
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arclight
Oooh that burglar's a cutie
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- Doug
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Change your ISO when you cannot achieve the shutter speed or lens aperture you want because the ISO you have set prohibits the settings you desire.
Suppose you have ISO 200 set and the fastet shutter speed that the light will permit is 1/250th with the lens fully open, but you want to use 1/1000th to freeze subject motion.
Bump the ISO up 800 (which equates to 2 stops) and you'll be able to set 1/1000 with the lens fully open.
Bracketing is where you take several shots and over expose and under expose each side of the exposure your camera meter indicates as correct.
E.G. if the camera indicated you shoot at 1/500 at f8 you could use f8 and take, say, 5shots at 1/125, 1/250, 1/500, 1/1000, 1/2000 (that is bracketing by varying each exposue by one stop - normally a half or third variation would be used in practice).
Similarly you could maintain 1/500 and vary the aperture.
The idea is that the camera meter may not indicate the optimum exposure therefore by taking a variety of exposures one will be correct (sort of scatter gun approach, but very effective).
Suppose you have ISO 200 set and the fastet shutter speed that the light will permit is 1/250th with the lens fully open, but you want to use 1/1000th to freeze subject motion.
Bump the ISO up 800 (which equates to 2 stops) and you'll be able to set 1/1000 with the lens fully open.
Bracketing is where you take several shots and over expose and under expose each side of the exposure your camera meter indicates as correct.
E.G. if the camera indicated you shoot at 1/500 at f8 you could use f8 and take, say, 5shots at 1/125, 1/250, 1/500, 1/1000, 1/2000 (that is bracketing by varying each exposue by one stop - normally a half or third variation would be used in practice).
Similarly you could maintain 1/500 and vary the aperture.
The idea is that the camera meter may not indicate the optimum exposure therefore by taking a variety of exposures one will be correct (sort of scatter gun approach, but very effective).
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- Dave
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Genrally you should up the ISO when there's not enough light to get the desired shutter speed. The D90 has an Auto ISO feature which automatically changes the ISO up to a certain point if required, it's pretty useful.
Bracketing is where you take three exposures, one underexposed, one over exposed and one normal. You select how much over/under exposure you want for the other two. Handy for anything you want to put into HDR or if you just want added security of having the two extra shots just in case.
Bracketing is where you take three exposures, one underexposed, one over exposed and one normal. You select how much over/under exposure you want for the other two. Handy for anything you want to put into HDR or if you just want added security of having the two extra shots just in case.
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- Richard
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You get best image quality at lowest ISO. It is usually pretty good up to ISO400 or 800 depending on the camera, and then gets quite bad with too much noise after that.
Generally speaking it is easier to work with high ISO, especially to ensure a shake-free shutter speed, but you have to balance the trade off against image quality.
Shoot a few test pics at different ISO settings and enlarge them on the PC and see what you think. If you only view quite small, or make small prints, you might not notice much difference but you will if you make a big print.
Noise reduction, either in camera or in post processing, makes a big difference
Generally speaking it is easier to work with high ISO, especially to ensure a shake-free shutter speed, but you have to balance the trade off against image quality.
Shoot a few test pics at different ISO settings and enlarge them on the PC and see what you think. If you only view quite small, or make small prints, you might not notice much difference but you will if you make a big print.
Noise reduction, either in camera or in post processing, makes a big difference
BarryG
I'll stick to my 2 inches
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^ Put your camera in aperture priortity mode and select f8. Have a look on the LCD and note the shutter speed the D90 has selected. Now change the ISO and watch what it does to the shutter speed. Higher ISO, faster shutter speeds.
It all depends what sort of light is available while you do the test, but for the purposes of this test, don't do it outside.
On the D90, I would stay away from ISO1600 and above. Up to ISO800 is mostly fine with no noise/grain.
It all depends what sort of light is available while you do the test, but for the purposes of this test, don't do it outside.
On the D90, I would stay away from ISO1600 and above. Up to ISO800 is mostly fine with no noise/grain.
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- Lawrence
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I am more than happy to use much higher ISO's than this, if it means getting shot.
The picture on the left is 6400 and the one on the right is 200. I know there is visible noise on the 6400 one, but I would use it if I had to.
I agree, my D5000 (same sensor) has excellent noise even at the very high ISOs.