Saturday, May 23, 2009
the Long Exposure experiment
On Friday night I decided I was going to try doing long exposures for the first time. Not just long, but really long. I had one location in mind, but apparently the police thought I was being suspicious parked in a private parking lot looking at things in an industrial area at 1130pm and so I sorta had to leave. You can't really stare down someone watching you from a police car and win. :)
So I went for a drive and came across a farm building I had photographed before, but had not seen recently. It is, of course, being torn down and will probably be a Tim Hortons or a gas station or something in the future as it is in a good location for that...
So I parked, did a quick walk around with my flashlight in hand. It was pitch black, 75% overcast and no street lights for at least 150m ( and not falling on the building at all).
I set up the tripod with the intent of doing some straight on images of the farm house with trees. So I tried several exposures of 15 -30 seconds at different ISOs to see what was what, and slowly increased the time. Past 30 seconds, I switched to BULB and used the remote. I tried to keep to ISO 100 or 200, fully manual at between F4 and F6.3 (for a little depth).
The first image above was a CR2 raw image was shot at 0141hrs: 563 second exposure (around 9mins) done at F5.0, 0ev bias, fully manual, on BULB, with a wireless remote, ISO 100, 24MM. All I did in Lightroom post was clean up a little noise, adjusted the white balance (distant lights of Highway 401 were causing an orange tint), and added a vignette.
I had to contend with cars coming by and so several of the shots I did I cut short as a car turned down the road and I got lovely but damningly unwanted light trails and headlights on the house...
I eventually repositioned the camera to a slightly different vantage point about 30m further down the road so as to capture the excavator on the property as well as the house. The change in angle gave me a view in the distance of the 401 and its light trails in one spot. So I collapsed the telescoping legs of the tripod and that allowed me to not see anymore light trails. It also altered the perspective of the shot as I was now closer to road level which was about 1m below the bottom edge of the house.
The image below, which was the last of the night, was a CR2 raw image shot at 0242hrs: 600 second exposure (ten mins on the nose) done at F5.0, 0ev bias, fully manual, on BULB, with a wireless remote, ISO 200, 24MM. Same post work as the other image.
One interesting and unexpected thing I encountered - aside from a fox, were the write times to the card. The long exposures - about 8- 9 MB files each time) at 100 and 200 ISO would take several minutes to record to the CF card (a SanDisk Extreme II). Regular 8-9MB shots same ISO during the day don't take anywhere that long, but it was perhaps not surprising given the amount of data that was being written.
The images are not sharp and I was disappointed by that. Even with a tripod, in near total darkness, focusing manually is pretty much impossible. I put one of the focus marks on the house - as best as I could tell. I shined a flashlight in one hand and tried to see the light falling on the house through the viewfinder but it was still pretty iffy.
For composing the shots, I quickly came up with the following technique. Shoot a frame at ISO 1600 for say 20-30 seconds. It will buffer much faster, and while it won't be a useful image, it will actually allow you to see what you have in front of you. You can then make any slight pan, tilt, or swivel adjustments to the camera as needed. I did that and then shot another test, and there you go. I am sure thats nothing new to a lot of you out there, but I came up with it on the fly - mainly because I didnt want to wait 6-10 mins to see if something was in the frame, was level and such. I had never shot using Bulb before last night either.
I stood around a lot doing this. I was there about two and a half hours, and shot only about 25 images. And several of those were the short targeting ISO 1600 ones. The waiting while the exposure was taking place, and the waiting while it was buffering was interesting. As was the light amount of tension (pun intended) caused by hearing cars and hoping they would not come down the road and ruin another shot.
Recommendations: Flashlight with a red filter. Turn off the display on the back of the camera so your eyes adjust. Remote trigger for the camera. Sturdy tripod. ISO 1600 for framing. A powerful light and someone else to aim it for initial manual focusing. A warm jacket -depending on the season. A road less travelled. And a good deal of patience.
I had almost all of those last night. An assistant would have been helpful though. You can only chant so many mantras in ten minute blocks, and having someone to chat with would have been good... :)
Mike Wood Photography
Posted by Mike Wood at 13:54