I have successfully taken long exposures on film using ambient light only and also night time flash images. I would like to create a slightly more balanced image that is a combination of both but using a continuous light source instead to hopefully achieve a more controlled lighting of the foreground.
Ive attached a photoshop mock up of the rough kind of idea i'm looking to achieve - ideally a long exposure star trailed sky in the background with foreground detail visible using the continuous lighting source. I have got ok results with this type of image before using a flash but it proved to be hard to control. Is there any way for me to gauge a successful exposure for the continuous foreground lighting? Can I use an incident meter on the foreground with the light on and then just switch the light on for the approximate time and then switch off and leave the long exposure to carry on? The locations I would like to try some images like this are quite remote so little to no light from nearby buildings / roads etc.
I suggest that you start with the Jiffy Night Calculator and then add fill in flash. I have been using the Jiffy Night Calculator since it was first published in 1963.
Thanks for replies. I have used the jiffy calculator before but don’t think it is useful for this situation as I said all light will be artificial ie: continuous light source whilst running a 2 hr exposure for the star trails in a very dark location. Perhaps if I rephrase my question. Can I use an incident meter to meter an artificial continuous light source for foreground illumination and then just switch the light on for that given amount of time during the exposure?
If it was large format, I would set up the camera focused on the foreground and light the ground as well as possible - and make the shortest possible exposure. Then get rid of the light, refocus on the stars, and start the long exposure.