Large Format Photography Australia

I'm still learning... I think.

Just been reading my LF Technique book and come across 'the bellows factor' which needs to be calculated after taking a light reading.
No one has mentioned that.
Let's hear something about that.

Paul,

you might find it is fairly commonplace for folk on forums to answer the question asked - particularly to a newbie - and not to broaden the topic.

If you have a spreadsheet app on your iPhone I can send you a sheet that calculates it.

Waltzing Paul wrote:Just been reading my LF Technique book and come across 'the bellows factor' which needs to be calculated after taking a light reading.
No one has mentioned that.
Let's hear something about that.

Paul,

Bellows factor is based on the inverse square law of light.

Have a look here for its explanation: http://www.youtube.com/watch?v=IYMKERZ4sZo

Light's intensity drops as you move the subject from the source. In our (simplified) terms, that refers to the film being moved further from the subject due to lengthening the bellows' draw. Thus, it dims the light hitting the film.

If you know this, then you can add additional exposure based on how far the film's moved back/how much bellow draw you have.

Plenty out there on it. As I shoot mainly landscapes, it doesn't really affect me.

Walter, sorry I don't have an iPhone.
I do have the instructions though in the book I have.
Just another thing to factor in when I get going.

Lachlan, just watched the youtube link you posted.
Thanks, that explains it very well.
As my interest is mostly going to be landscapes I shouldn't have too much to worry about.
Although I did have a practice this afternoon at shooting one of my orchid flowers up real close using a 90mm lens.
Very impressed to get it to fill the 4x5 frame.