Slow Shutter Speed Problem

sNarah

Hi Guys

Just a quick question here.

I went out today to the beach and thought it be good fun getting some pics of the tide going on slow shutter speed. So, set the camera on shutter priority with a range going from 1/3 to 4" on the shutter speed.

All pics came out white Aperture automatically was set on F32 and I wasn't able to put it lower. I tried to completly underexpose by putting the exposure on -2 and tried changing the ISO, but to no avail.

Any advice on what I'm doing wrong? I presume i need to adjust the aperture (will have to read manual to check how to do it), but apart from that, can yous think of other reasons why the images turned out all white?

(I should probably also mention that I'm a complete gymp when it comes to the technical aspect ...)

CabanSail

If it was during the day then it is going to be WAY too bright for exposures of that length, even with the smallest aperture & lowest ISO.

What you need is some ND Filters to cut the light down, probably a ND8 or more if it's sunny.

stick-dan

Thanks cabansail i was having the same problem. off to the shop

sNarah

CabanSail wrote: »

If it was during the day then it is going to be WAY too bright for exposures of that length, even with the smallest aperture & lowest ISO.

What you need is some ND Filters to cut the light down, probably a ND8 or more if it's sunny.

Aha... Mjah... That does make sense now that you mention it ... Thx, will have a look into them! (and my wallet...)

ND "8" I take it is the strenght of the filter? Is there much difference in them?

CabanSail

Just adding that changing the EV Compensation is only adjusting the metering, not changing any of the optics (if that makes sense?)

DaireQuinlan

You've essentially selected a shutter speed that's too slow for the camera to compensate for. The camera tries, by setting the aperture to f/32, but even at that the shutter speed is too long, and the picture overexposes. 4" is a long long time ...

Just to demonstrate, put your ISO as low as possible, and using Av stick your aperture up at f/32. Now point the camera out the window. Its a bit overcast today, but I reckon you'll probably get 1/12 or 1/25 at the very least. 4" is about 5 or 6 stops faster than that.

Generally, if people are doing these long exposure shots they'll use a ND filter, or Neutral Density. Essentially this will cut down the amount of light coming through the lens by as much as 8 stops, allowing you to use long exposures during the day.

D.

Ostrom

Get yourself a tripod first!

sNarah

CabanSail wrote: »

Just adding that changing the EV Compensation is only adjusting the metering, not changing any of the optics (if that makes sense?)

Huh? (= Nope, don't get it...:()

CabanSail

An ND8 will allow 1/8th of the light through. So that would the same as 4 Stops.

So if you were on the lowest ISO, f32 and were getting a shutter speed of 1/30th sec. Then an ND8 would allow you to shoot at 1/2 second. A ND16 would reduce that to 1second .... etc.

Paulw

A good tripod and an ND110 filter are brilliant for long exposures during daylight.

I've used this before. Very handy and some interesting effects.

CabanSail

sNarah wrote: »

Huh? (= Nope, don't get it...:()

If you set the EV to -2 it is telling the Light Meter in the Camera that the scene is actually 2 Stops brighter than it sees it, so it will then underexpose by 2 stops by adjusting the Shutter Speed of Aperture accordingly.

As you had run out of Aperture settings, changeing the EV is not going to make any difference. The camera cannot adjust any further. The only thing you can do is to reduce the light. This can be by way of ND Filter or the cheaper method of utilising Astronomic Rotation Exposure Adjustment (AREA)

Do you know how to use AREA with your Camera? I have used it with my Nikons for years now.

Hugh_C

sNarah, the photo below was taken yesterday during a gale in Brittas using an ND6, 6 sec exposure, ƒ/16, ISO 200 (with a tripod). A pretty overcast day but even so, I needed the ND6 to get that length of exposure ...

uaigneas

.

sNarah

CabanSail wrote: »

If you set the EV to -2 it is telling the Light Meter in the Camera that the scene is actually 2 Stops brighter than it sees it, so it will then underexpose by 2 stops by adjusting the Shutter Speed of Aperture accordingly.

As you had run out of Aperture settings, changeing the EV is not going to make any difference. The camera cannot adjust any further. The only thing you can do is to reduce the light. This can be by way of ND Filter or the cheaper method of utilising Astronomic Rotation Exposure Adjustment (AREA)

Do you know how to use AREA with your Camera? I have used it with my Nikons for years now.

Ok, I get the EV one now! (Yay)

And AREA I've never heard of - aargh, here kicks the complete unawareness in again, hate it when that happens! - would that be an 'in'camera feature? I shoot Sony you see... I really shoúld read the manual again I think :rolleyes:

Ok so what I've learned today:
Low Shutter Speed @ Broad Day light
1/ Low ISO
2/ ND Filter or this AREA Thingie
3/ Tripod
and should I still put the EV down even with a ND filter? And I suppose best to shoot in shutter priority mode?

Anyho, all the help and answers are réally very much appreciated, thanks guys!!

CabanSail

I am sure that the Sony System can use AREA, even Canon's!!!


Astronomic Rotation Exposure Adjustment (AREA) is where you utilise the Rotation of the Earth & as that happens it gets darker.:D (some call it Night)


The EV Setting is used if you want the image to be overexposed or underexposed, according to the meter. Use it in situations where you know the lighting will trick the camera meter. Light Meters work by assuming that the world is 18% Grey. They then set the camera up so that it acheives that. There are situations where it is not 18% Grey & you need to adjust for it. eg. In the Snow you want to set the EV to overexpose as the scene is mainly white so a lot less than 18% Grey.

Morrisseeee

And try a polarizer aswell, adds another stop or two, and reduces glare and gives the sky/clouds a nice balanced look.

CabanSail

Forgot to add ..... If I were setting up to do this I would probably use Aperture Priority, set at the smallest possible. The camera will then select the longest Shutter Speed it can in that situation.

Calina

Hi Sarah,

I have been doing these too lately. See this one (I've posted it before)

It was a 30 second exposure at f20, done after sunset. It had two ND grads and a tobacco grad stacked - from this list the P121, P121M and P125L. I shot it at ISO100 as well.

Basically, if you're trying to do this, you need to do everything you can to slow the exposure down. During the day, really you need a bundle of filters to do it. I don't think even the ND8 on its own would be adequate to take you to a slow enough shutter speed.

Morrisseeee

As an example, this was taken (back into the sunlight) at 1.6seconds while using a NDx8 filter & polarizer.

Duchovny

I usualy do long exposures during the day and i have a B+W 110 (3.0) that gives me about 10 stops.

Here one example.
Sorry about the size of the picture.

Hugh_C

CabanSail wrote: »

Forgot to add ..... If I were setting up to do this I would probably use Aperture Priority, set at the smallest possible. The camera will then select the longest Shutter Speed it can in that situation.

don't know whether I entirely agree Caban, a lot of lenses will have their sweet spot somewhere in the middle of the range, with the lens stopped right down you may be introducing flaws. Another thing is that at say ƒ/22 on my camera, every tiny speck on the sensor becomes very obvious and you have to spend a load of extra time in post cloning them out. The long exposure stuff I've been doing recently has been around ƒ/11 or 16 (max)

CabanSail

I agree with what you say, but to get the longest shutter speed in bright light you will have to go to the minimum aperture.

Duchovny

I do ofter use F22 or F29 as I like a lot to see the clouds moving and I don't think they came out that bad.

DaireQuinlan

CabanSail wrote: »

I agree with what you say, but to get the longest shutter speed in bright light you will have to go to the minimum aperture.

Not necessarily. If you're using an ND in the first place to cut down the light then you can always use a stronger ND, or stack a couple together, or use an ND and a polariser to get a couple more stops reduction.

Using a cropped sensor you start getting diffraction limited around f/11 or thereabouts right ? With 35mm film (or FX) I'd never stop down past f/16 unless absolutely necessary because of the same issue.

sNarah

Wow, my brain is in overkill at the moment reading all this

But, check check and check. Have save all the comments in a file somwhere and will make the best out of it.

And I'll just experiment with the F numbers, starting somewhere around F11 or so and then start pushing it up bit by but... And see what happens!

Thanks for all the advice, I feel a lot wiser now and it is very much appreciated!

GhostInTheRuins

CabanSail wrote: »

Astronomic Rotation Exposure Adjustment (AREA) is where you utilise the Rotation of the Earth & as that happens it gets darker.:D (some call it Night)

I can't believe I actually went a googled that. I knew something was up when your first post was the only result.

ttcomet

I would recommend getting Cokin or Lee filter sets rather then those screw in ones, that way you can use the filter with different size lens's.

5uspect

Another option is to stack up two polarisers to make a variable ND filter.
A linear on top of a circular polariser will give the best results.
Then you can rotate then relatively to control the blockage.

TheNorthBank

I raised a Thread here a while back about ND filters, not sure but it might be of some interest: http://www.boards.ie/vbulletin/showthread.php?t=2055495070