Technical question - DPChallenge Forums

Canon EF 17-40mm f/4L USM

03/27/2006 09:38:04 PM · #1

While trying to shot my "Water" shot I wanted to experiment with my camera which has up to a 15 second shutter speed. I had read that leaving the shutter open gives that soft dreamy look on running water. So, I put the camera in "S" mode and adjusted the shutter speed to 15s. I used a tripod and pushed the button. Waited (the shutter was heard firing) and then the LCD said "processing". But... all I ended up with was a pure white image! So I lowered it and lowered it, same thing over and over. I wasn't until I got back down to 2 seconds that I could get an image. What am I doing wrong? Is it me or the camera? In "S" mode, everything else is supposed to be automatic.

LoudDog

Canon EOS-350D Rebel XT

03/27/2006 09:50:01 PM · #2

You are way overexposing. Try the same shot at dusk and experiment with different shutter speeds.

GeneralE

Canon PowerShot S3 IS

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

03/27/2006 09:51:19 PM · #3

At that long an exposure, with the lighting conditions you had, even your smallest possible aperture lets in so much light that you are getting an overexposure -- people use neutral-density filters precisely to address this situation.

rob_franklin

Nikon D70s

Nikon AF-S DX Zoom-Nikkor 18-70mm f/3.5-4.5G IF-ED

03/27/2006 09:55:41 PM · #4

you gotta wait till it gets darker....leaving the shutter open not only blurs movement during the time it is open, it also lets in light.

Here is a similar picture that was taken by your camera model.

i dont know anything about your camera but if you can turn the ISO to its minimum setting and raise your aperture to its maximum number setting you can reduce the amount of light that the camera lets in(buying you a little more time).

your owners manual should tell you how to do those things....or just wait till it is almost dark outside.

Canon EF-S 17-55mm f/2.8 IS USM

03/27/2006 09:55:58 PM · #5

The filters I have are "UV", "FLD" and "PL". Would any of these help? Or should I only try this at dusk?

eschelar

Canon EOS-7D

03/27/2006 09:57:24 PM · #6

I've actually taken some 15 second exposures successfully without ND filters and these kinds of pictures are VERY specific to the amount of light you can allow in the scene. Anything over around 2 seconds has to be pretty much dark. Dark. Light sources used in such photographs need to be applied in only brief moments.

This is often where the term "light painting" comes up.

Soft flowing water effects can be had as low as 1/4 second.

Balancing the light in your scene can be quite a challenge.

Sigma 24-70mm f/2.8 EX Aspherical DF for Canon

03/27/2006 10:04:45 PM · #7

Thanks for the help everyone. That's what makes this such a great place. I'm going to try this again tomorrow at dusk and play around. There is a full manual mode and maybe I'll get brave and try to play with that too.

hankk

Canon EOS-5D

03/27/2006 10:07:57 PM · #8

Originally posted by kdsprog:

The filters I have are "UV", "FLD" and "PL". Would any of these help? Or should I only try this at dusk?

The PL may help if its a circular polarizer. If its a linear polarizer, it may thow your metering off entirely.

UV will protect the lens.

I think FLD is a fluorescent to daylight correcting filter (it is if its purple).

The FLD is kind of useless on a digital camera because you can use AWB or set the WB. However, if you can set the WB with the FLD, it will act to reduce the amount of light coming in, but probably not nearly enough to get you to 15 seconds.

faidoi

Pentax K10D

Pentax DA 18-55mm f/3.5-5.6 AF

03/27/2006 10:33:58 PM · #9

ND filters will help with that misty look.

You may try some sunglasses to see what you can get if you are budget minded. If you have some self car tint that may also work. You are basically trying to trick the lens to think it is dark out.

eschelar

Canon EOS-7D

Canon EF-S 17-55mm f/2.8 IS USM

03/27/2006 10:57:15 PM · #10

I uploaded some shots just for you. Then I posted a long and detailed post about each shot. Then I accidentally hit the back button. @#^%$%&#%$&#$%^#%$^

Anyhow, here I go again.

These three pictures give you an example of how this works.

The first one was taken at ISO 100 with a relatively fast shutter speed of around 1/12.

I say relatively fast because it's easy to see that the soft flowyness isn't really portrayed very well.

A few moments later, I smacked the old forehead and switched to ISO 50 and started playing around with a narrower aperture. I ended up with the second image.

Note how by using the lowest ISO setting and tightening that aperture, I was able to cut down on light so dramatically that even with 1.5 stops more exposure, I am no longer getting such harsh highlights in the white flower.

No ND filter needed to be used because light was kinda poor at the time.

Having moved up to 1/4 of a second, the water has taken on a MUCH softer look and now looks 'flowy'.

It's also easy to see that this is about the limit as far as flowing effects by shutterspeed are concerned.

The third picture was taken 25 minutes later and dusk was arriving. Light dropped dramatically (probably a good 3 stops) during the 10 minutes that I spent shooting this one.

Sadly, part-way through my shot, my equipment (I used a mini-tripod) got commandeered by another photographer I was with (who is admittedly a much better photographer and did indeed work some stuff that I would simply not have thought of doing with that scene... the rest of which turned out so poorly in my pictures that I felt it necessary to crop away), so I didn't go any further. I could easily have gone to 3 seconds by waiting just another couple of minutes.

At 1.3 seconds, there's lots here to be learned as well. The water here doesn't just have a flowy, silky look, extra light has been captured that gives the 'white' areas a look that could almost be termed "magical".

This is a highly useful effect and it looks great if you do it well.

The darker the other parts of the picture and the longer the exposure, the more light you will catch from those turbulent areas and the more mystical it will look... To a point of course.

Oh yeah, I didn't use ND filters for any of these shots. I don't actually have any yet (been talking about getting some for months...).

On the other hand, these shots were taken in rapidly changing light circumstances. This is not usually desirable and ND filters would have allowed a certain control here that would have yielded the same results, but at a time when the lighting was a bit more stable.

Message edited by author 2006-03-27 22:59:43.