Archives for : December2009

What I use for long exposure shots

I thought I’d write a note about how I go about taking these long exposure shots, what gear I use etc.

The main piece of kit you need is a neutral density filter.  I have a 10 stop filter, or ND1000 as it is.  That means it blocks out 10 stops of light, which quickly means you need to start taking very long exposures.  I have a B+W 77mm filter and a step up filter so I can use it on a couple of lenses.

I also use a tripod (a Manfrotto x055 Pro) with ball head and a cheap ebay remote trigger to avoid any unwanted shakes.

Because the filter is so dark when it is on the camera it’s impossible to see anything though the viewfinder and the camera will notbe able to meter or auto focus.  So you have to setup the shot with the camera on the tripod and the camera in manual focus (or use AF then switch to M).

Once the shot is composed and focused you need to take a meter reading of a properly exposed shot without the filter so that you can use this to determine the exposure 10 stops lower.  You will need to keep the aperture the same between the normal shot and the long exposure shot with the ND filter and only vary the shutter speed so as to maintain your desired depth of field and focusing.  I do this by taking a reading in Aperture priority mode and then switch to Manual mode for the long exposure.

Once you know the shutter speed you need for a normal exposure you’ll have to work out what 10 stops (or whatever filter strength you’re using) less than that reading is.  I use a printout of this chart for looking up the exposures.  Simply look up the reading you’ve taken across the top and then read the shutter speed off in the 10 stops row.  So a reading of 1/60th becomes 15s and 1/8th becomes 1 minute (as you can see it very quickly can get into exposures of minutes in length).

Once you’ve worked out the exposure you’re going to need, carefully screw the ND filter onto the lens making sure not to move the camera setup or adjust the focusing on the lens.

For shutter speeds up to 30s I can use the normal manual settings on my D300.  For anything longer I have to put the camera into “Bulb” mode and then use the remote release.  You can do this by pressing the button once to open the shutter then counting using a watch before pressing the button again to close the shutter.  My trigger allows me to input in the exposure time I want and let it do the counting and releasing the shutter leaving me free to keep my hands warm in my pockets.

The camera settings I use are 14 bit lossless compressed RAW recording with a neutral picture profile.  I leave long exposure noise reduction on.  I can then make best use of the files back home on the PC.

On my D300 the camera will do its own long exposure noise reduction in camera and I reccomend that you use it.  It gets rid of a lof of sensor gain noise that you’ll otherwise spend ages removing with a clone tool in post production.  The only problem with it on the D300 is that it takes as long to do this step as it does to take the picture.  So if you take a 15 minute picture it’ll take 15 minutes to perform the NR, which is a bit annoying, I think that the D3 and D700 are faster in this regard.

The long time that it takes to take just one long exposure shot means you end up spending a lot  more time setting up a shot and making sure that it’s composed well and it just so before you take it.  Because if you didn’t you’ve just wasted a good 5 minutes.

Woodland Gardens (long exposure)

30seconds using 10 stop ND filter

We went down to Busy Park to get out of the house after Christmas.  I thought I’d bring all my gear along and my tripod and try out using my 10 stop ND filter that I got for christmas last year.

This shot was 30 seconds long at f/10, ISO 200, 12mm.

I wish it’d been a bit windier and the clouds a bit more interesting so that there’d be some movement in the tree branches and a more dramatic sky but despite that I got a few decent shots, this one being my favourite.

New photobook has arrived

Last year Beth and I got a photo book made to celebrate our first year together, it’s A3 sized and had about 30 pages of prints in it.  All very well made from photobox at least until the bunny chewed the corner of it!

We decided to do the same this year for our 2nd anniversary but work and things got in the way for a good month and a bit.  We finally got around to it and even though we thought we hadn’t taken that many pictures this year we still easily managed to fill a book and then some.

It finally arrived this morning (our anniversary is at the end of September) and it looks great.  I only had time to see the first few pages this morning as I had to dash off to work, but I was very impressed.  I’ll post up a few photos of it on here later when I get home.