I usually take all the real estate photos without flash. The reason is that I want to generate warmth in the photos without having hot-spots in the front, and dark in the back (of the rooms). I do own studio flash units, but they take time to set up correctly for each room. My normal mode of operation is to take photos of each room without flash. This is much quicker as I can take 30 - 40 shots (I always take 2-3 duplicates of each shot) of an average house in less than 30 minutes without flash. If I were to take the time to set up my studio strobes in each room, it'd probably take more like 90 minutes to shoot the same house.

 

You can see some of my results here:

 

ALL of the above photos were taking without flash using a tripod and a somewhat longish exposure.

 

By the way, if you are concerned about the flash rating, it is usually specified in GN or Guide Number, which is a rating of how powerful it is. For instance, my on-board camera flash (digital Rebel) has a Guide Number of 43 (iso 100, ft) and my external hot-shoe mounted flash has a GN of 142 (iso 100 in feet), while my studio strobes have a GN of between 80 and 220 (iso 100 in feet), depending on the reflector used.

 

The higher the number, the more powerful the flash. To calculate exposures, take the GN and divide it by the distance to the subject will yield the aperture (f-stop).

 

Example: GN 142 divided by 10 feet = aperture of f/14 (iso 100) for proper exposure.      

 

 

Steven Hong, REALTOR, e-PRO