Bulb Exposures

[tpinchback]

How and why do people use the bulb exposure?? When to use it and when not too?

[dtrayers]

I use it mainly for photographing lightning and firewooks.

However, since I got my 300D last fall, I haven't had the occasion yet.

[Scottes]

Astrophotography - stars and stuff. Low light - when the shutter time goes beyond the built-in timer, you have to use Bulb and a stopwatch. Try taking a pic at midnight under a crescent moon at f/22 and you'll be using Bulb.

[tpinchback]

About what is your longest exposure using bulb without the sensor getting really noisy?? Do you have to hold the shutter open with your finger, or is there a way to keep it open without your finger being on it the whole time?

[tpinchback]

I use it mainly for photographing lightning and firewooks.

However, since I got my 300D last fall, I haven't had the occasion yet.
Astrophotography - stars and stuff. Low light - when the shutter time goes beyond the built-in timer, you have to use Bulb and a stopwatch. Try taking a pic at midnight under a crescent moon at f/22 and you'll be using Bulb.


Great ideas!!

[tpinchback]

I sure did mess that post up :shock: Sorry :D :)

[iwatkins]

Hey, happens to us all. :)

To hold it open longer than 30 seconds, you can of course just stand there with your finger holding down the shutter release. But of course you'll introduce camera shake.

What you need is a wired remote control. This has a shutter button on it that you can press down and lock. The shutter will then stay open until you unlock it.

Another remote (more expensive, obviously) has a little LCD display where you can dial in an exposure time. When you press the button on this remote it will hold the shutter open for you for this period and then close it again afterwards. i.e. you don't need to be there or need to remember to unlock the release again.

As for long exposure times and sensor noise, well, I don't really know as I've never done anything much longer than a couple of minutes.

The one thing I do know is that the 10D and the 300D sensor is very good for noise over long periods compared to many other cameras.

A lot of noise will be caused by heat in the system so if the camera is out on a cold night it will be less noisy for a long period compared to the same setup on a very hot night. Lots of other factors in sensor noise as well though.

Cheers

Ian

[tpinchback]

Thanks Ian!!!

Just the anwser I was looking for. I'm glad the 10d is very good about noise issues b/c I like to take alot of night photograghy :lol: :D

thanks

[Scottes]

Just the anwser I was looking for. I'm glad the 10d is very good about noise issues b/c I like to take alot of night photograghy

Neutral Density filters can add a bit to "night" shots. Try them about 30 minutes after sunset, when the sky is still blue. The ND will slow you down, allowing for light trails and such, but you can still get the color on any static objects.

[rodbunn]

Sometimes if I'm shooting the inside of a large church or the reception hall I set the camera to BULB and have an assistant run around the whole place firing a flash to light up everything evenly. As long as the assistant keeps mooving, they won't show up in the photo..... I havn't done this with my 10D yet but the next time I can I will and then post it.

Thanks, Rod

[iwatkins]

Also fun to try is to take a picture of a busy motorway (freeway) and end up with a picture so it appears totaly empty.

Haven't tired this with the 10D, but on my film Canon.

I have an ND filter which is very very very dark, can't put my hand on it at the moment, but it is called something like an ND 1000000 or something silly like that.

It allows you to make a long exposure (from memory) of something like 15 minutes in bright sunlight.

This way you can have a picture that is exposed just right and anything that moves just doesn't appear in the shot at all.

I used a whole roll of film once and I got one good exposure out of it. :D

Cheers

Ian

[tpinchback]

Sometimes if I'm shooting the inside of a large church or the reception hall I set the camera to BULB and have an assistant run around the whole place firing a flash to light up everything evenly. As long as the assistant keeps mooving, they won't show up in the photo..... I havn't done this with my 10D yet but the next time I can I will and then post it.

Thanks, Rod

Never thought of that, great idea!! The exposure comes out evenly?

thanks

[rodbunn]

It takes a portable flash that you can set the output to like the
550 or the Quantam... Also, it takes an empty church or hall.
Anyone in that moves a little will be a little blurry. I saw this
years ago in a magazine article, the guy was really creative. He
would run around himself ( I'm too old ;-) and highlight things
he wanted lit, or do the room as even as he could. You can
imagine it's tuff to get it real even..... The "Digital world" would be a
great place to try it. I just havn't had an oportunity, usually there's
people in the place by the time I get there...

I'll make an effort my next wedding to do it with the 10D and a portable
550.....

HEY try this in a dark room in your house, it's fun !!!!!

Rod

[tpinchback]

can you do it with the 420ex??? i hope so

[rodbunn]

As long as there is a manual mode you can set the f-stop
and then run around and hit the test fire button.....

[iwatkins]

You can use the same method for just about anything. If you do a google for "painting with light" you'll get quite a few hits.

You can do interiors with a big flash gun, you can trace the outline of a car with a penlight or laser pointer. etc. etc.

Guy here in the UK (can't remember his name) takes shots of large geological structures like limestone stacks/arches. He sets up at dusk and while there is still some colour left in the sky, opens the shutter then uses all manner of huge torches (you know the type, 3 million candle power rechargeable jobs) and sweeps the structures with the light. The results are so good you wouldn't know it had been lit this way unless you were told. The secret was to keep the light moving evenly and smoothly. To emphasis something you just slowed down as you approached it with the light beam then sped up again afterwards. To darken something you did the opposite.

The shots end up with lovely afterglow/blue/black skies but nicely lit limestone arches etc. He also lit the waves so they didn't look lit at all but just glowed a kind of bio-luminesent green/blue. Looks magical.

Cheers

Ian