BTZS and Pinhole flare adjustment

[shannonstoney]

Hi, I'm using the Plotter program to generate some curves for pinhole. (I use a 4x5 Leonardo pinhole camera.) I noticed that there is a place in Plotter to set a flare adjustment. What would be a reasonable guess on the amount of flare to put in there? I'm guessing somewhere between 0.1 and 0.4? Or even more? Is there a way to test for that? (I don't have a densitometer right now handy, so maybe it will ahve to be trial and error.)

My film is HP5+ in DDX 1+5. Thanks.

 

[Bill Burk]

0.4 sounds as good as any... Although you have no optical glass to add flare due to light reflecting off of lens surfaces, you will have some factors which may be calculated as flare: atmospheric haze and light scattering inside the camera, (light bouncing off film from the brightest parts of the image, scattering inside the camera to find themselves back on the film in another location).

You can test for flare by making a "black box". I use a costume top hat for the purpose... Take a meter reading inside the hat to confirm it is really, really dark. Then shoot a picture of the scene including the hat. When you look at the negative... if the top hat is really, really clear... then you have little flare. The density of the top hat, if you can judge density, gives you what you need to calculate the flare factor.

 

[TheToadMen]

Hi, I'm using the Plotter program to generate some curves for pinhole.

Could you tell me what this Plotter program is? I don't know it.
Thanks,
Bert from Holland

 

[juan]

Plotter - http://www.btzs.org/Software/Plotter.htm