The highest quality interior photography techniques have generally been reserved for Magazine and High-End publications. We have finally developed processes to make this these techniques quicker and bring the pricing down to a reasonable enough level to use for real estate listings.
Since most realtors haven't used these techniques we would like to take to time explain how to spot the differences in quality in photos.
Single exposure: With a full frame DSLR camera on a tri-pod a single exposure can often be edited to make interiors and window exteriors visible. Bust since window light is almost always a different color then the interior light the rooms will have color issues. Walls near windows appearing blue/green is very common.
Direct Flash: Use the same single exposure Technique but adding a on camera flash pointed directly into the room will flood the room with clean white light to help eliminate the color issues around the windows. Direct flash will cast hard shadows into the room from lighting fixtures and have a very flat/fake feel to them due to erasing all the natural shading. Bright reflections of the flash in shiny objects
HDR/Multiple Exposure: Using multiple images (one brighter, one darker and one in the middle) software can be used to keep the window exteriors from the from the darker image combined with the interiors from the lighter image. HDR often creates vivid color window views of the exterior but color issues still remain and are often made worse by the processing.
Soft Off-Camera Flash: Here the flash is removed from the camera, often up higher above the camera and placed in an umbrella/softbox. The umbrella/softboxes makes shadows cast by the light significantly less notable (soft edges instead of hard lines) and raising the light up higher casts more pleasant shading into the room so it doesn't look so flat. In unfurnished rooms this technique often indiscernible from high-end techniques.
This technique is my secret but when you'll see is that the exteriors are clearly visible like HDR and Flash images; the interior colors are perfect and consistent and the shading in the room is natural and appears to be coming from the rooms actual light sources.