Depending on the water speed, you shouldn't really need that long an exposure. usually you get good results from 1/4 - 2 seconds. That said, you will really want to get a 3-4 stop neutral density filter. You can couple that w/ a circular polarizer for an additional 2 stops if needed...
All you can do - without filters - is to use the lowest ISO setting and the smallest aperture..
Exposure compensation as such is irrelevant, as that is merely an instruction to the camera, but when you have reached the physical limits of the available settings, it means nothing..
So, two solutions. One is to shoot at time of day when the light is dim, i.e. dawn or dusk. Not very convenient, though it does work very well, in the few minutes available at each end of the day. Second solution: neutral density filters.Regards,Peter..
I recently have been attempting to use slow shutters (2-8 seconds) toslow down the effect of water in streams, rivers, etc...to go forthat "smoothed look"....
My exposures have been completely white, totally blown outframes....even though I closed the aperture down, put on 2-3 stops ofnegative exposure compensation etc...just can't seem to take one thatisn't blown to hell..
Do I need filters, etc......PLEASE HELP!! LOL.
Thanks so much in advance for the help all.
First, keep in mind that your goal is to produce a proper expsoure, only with a slower-than-normal shutter speed. Thus exposure compensation is not an appropriate tool: if you underexpose, your shutter speed will be shorter, which is not your goal, and you will have an underexposed picture. If you overexpose you will make the shutter speed longer, but you will have an overexposed picture, and it will be the water that blows out first, which doesn't look silky (it just looks blown out!).
Basically, you want to meter the scene normally, using the smallest aperture you are comfortable using (very small apertures can decrease sharpness), and the lowest ISO available on your camera. If the resulting shutter speed is not slow enought to produce the effect you are after, then you need to apply some form of neutral density. That can be as simple as a polarizer you may already have, or it may be actual netural density filters. But you will need to limit the amount of light getting into the camera, no way around it..
As others have pointed out, you proably don't need a shutter speed as slow as 2 - 8 seconds. I find that water that is moving or falling fairly fast usually gives a nice effect starting at around 1/2 second; too much can actually just look like a white sheet. For more slowly moving water, riffles and whirlpools, for instance, then several seconds may be appropriate. Start out with a shorter speed and see if that is adequate before shooting for a longer speed..
Thanks Dave, and everyone who replied, I really appreciate the time....
Johnny, as others have said, it's all about getting a correct exposure with a long enough shutter speed for the effect you want. From what you said, you know that you need to stop down to lengthen the shutter duration. However, as you've found out, even at f/22, you will overexpose if you expose for too long, which is easy to do in good light. Shooting in the shade or at times of the day when light is dimmer makes it easier to get longer exposures without overexposing..
As an exercise, shoot in Av metering mode at low ISO and take some shots of the scene, adjusting exposure compensation each time (if needed) until you get an exposure that looks right. The histogram is a useful tool in helping to judge correct exposure from the image review..
Take a note of the shutter speed the camera used for that correct exposure. If you want to use a shutter duration of say 1 sec for smoothing out flowing water instead of that shutter speed, you know you somehow have to reduce the light entering the lens by enough to increase the shutter duration enough..
If the shutter speed from your testing was say 1/8 sec, then adding a 3 stop neutral density filter will require 3 stops more shutter duration, ie increasing from 1/8 sec to 1/4 to 1/2 to 1 sec..
Does that make sense?.
Another idea is to stack two polarisers. That gives you a continuously variable neutral density filter that varies from being as light as the two polarisers at their lightest, through to VERY dark as you rotate one with respect to the other..
Cheers from John from Adelaide, South AustraliaJohn Harvey Photography http://johnharvey.com.auCanon 40D, Canon 20D & Fuji F10..