Lee On Solent, View To East, 30 Second Exposure

Lee On Solent, View To East, originally uploaded by scalespeeder.

A little more long exposure practice.

1) When its dark you better know what all the buttons do on your camera, or bring a torch. (I don't, and didn't).

2) When its dark its very difficult to compose through the viewfinder.

3) When its dark, street lamps are very bright!!

4) When doing long exposures, its best not to choose a night when it's blowing a hooligan.

5) I need to research on how to work out how long an exposure should be when the shutter speed exceeds 30 seconds and I have to use bulb mode.



Cheers, Rob.

Comments

[Victor]

Hiya Rob,

Nice long exposures and a great start.

Night shooting is a pain, especially when it comes to metering the light. Most photographers avoid it by shooting just as the sun has set or just before it rises and meter from the sky.

Simple trick is to meter with your aperture wide open and back track your exposure or meter at a faster ISO and back track also.

For example:

If your reading is 20 seconds at f4 but you want to shoot at f16, then back track through the apertures. Each aperture stop down decreases your light by half so you need to double the exposure.
So f4 @ 20s = f5.6 @ 40s = f8 @ 80s = f11 @ 160s = f16 @ 320s.

So your exposure at f16 is 320 seconds or 5 minutes and 20 seconds. At least with digital you don't have to allow for the reciprocity failure of film!

The same is true if you meter at a higer ISO so:

15 seconds @ ISO3200 = 30 secs @ ISO 1600, 60 secs @ ISO800, 120 secs @ ISO 400, 240 secs @ ISO 200 and 480 secs @ ISO 100.

You could obviously use a combination of both for difficult situations. So if your meter reading is 2 secs @ f4, ISO1600 this is the same as 32 secs @ f4, ISO 100 and then if you want a smaller aperture this becomes 512 secs @ f16, ISO100 or 8 minutes and 32 seconds.

Simple maths and as I mentioned you don't have to allow for reciprocity failure.
Digital noise can become an issue with very long exposures in which case you split the exposures and stack the images post-processing but exposures of a few minutes should pose no problem.

If a strong light source is affecting your reading, (such as nearby street lamp), just simply meter through the finder whilst placing your finger or such over the light source in front of the lens and take your reading.

Now that I have my new dSLR and just finished building my USB cable release I hope to be getting some night shooting now that the nights are beginning to draw in!

Hope that helps out Rob, have fun and next time remember the torch ;-)

All the best,

Victor

[Rob_Nunn]

Hi Victor,

Great info, I can't wait to get out again!

Thanks for your great advice, Rob.