photoman022 Loc: Manchester CT USA

It's how I do it! And it's simpler than you think. Just expose for the outside light; keep that exposure throughout the process and add flash(es) to light up the room to proper exposure.

rmalarz Loc: Tempe, Arizona

Unfortunately, you'll be getting a lot of the usual 'lean on the crutch of HDR'. Ok, but that can tend to lead to very unnatural looking photographs.

First, shoot RAW.

Second, test your camera's ability to handle additional exposure. This is crucial. Once one knows the number of stops of additional exposure one can place the highlights at an acceptable level.

Third, Careful spot metering off the brightest part of the scene and place that value accordingly. This placement is based on the testing mentioned above.

After that, processing takes the stage and one needs to be knowledgeable of the various adjustment sliders in both RAW processing and the final image processing. It takes a bit of time and dedication to achieve this level of knowledge and skill.
--Bob

w00dy4012 Loc: Thalia, East Virginia

w00dy4012 Loc: Thalia, East Virginia

Kozan Loc: Trenton Tennessee

The D850 will shoot in-camera HDR. I believe it shoots two shots and combines in-camera. Set it to shoot -3EV and +3EV. That should be enough.

Or, you can set it to Continuous High and shoot 5 images at -2 and +2EV for each shot, then combine in Lightroom. (I use Affinity Photo.)

ecurb Loc: Metro Chicago Area

Well you can shoot like a movie production and use big rolls of combined 85b and ND filter on the outside of the windows and light the interior with hot (3200K) lights.
You can light with studio strobes ( I've used multiple blue flash bulbs before strobes ) to balance to the daylight color and intensity.
Twice a day, at dawn and dusk the outside light will balance in color and intensity to the interior. This allows you to light the interior with hot lights.
Or just do HDR.
The cheap and dirty real estate photo method is to just bounce an on camera flash off the ceiling.

PHRubin Loc: Nashville TN USA

That sounds right, but I used a more manual flash and set the aperture as required for the flash, and the shutter speed as required for outside to get the first shot. It didn't have a head that could be turned around. Too bad the box was there and I didn't move it. This was taken about 40 years ago. It is a scan of a 4X6 print. It was part of an exercise showing 2 different ways to shoot with a window in the scene. The second was just ambient light.

David in Dallas Loc: Dallas, Texas, USA

I run into that situation a lot on my tours while trying to photograph interiors. Since I'm usually not interested in what is outside the window, I try to expose for the interior and just use LR to mute the highlights, dimming the window. If necessary, I also boost the shadows. I don't shoot RAW, so the ability to reconcile is limited.

E.L.. Shapiro Loc: Ottawa, Ontario Canada

Gene's IS the best and most practical approach as far as a lighting strategy.

If the interior is naturally illuminated by incoming exterior natural daylight, you can fill or main-light the interior furniture with electronic flash. I often use old-fashioned BLUE PHOTOFLOOD LDMOS or I replace the regular light bulbs in the table and floor lamps with 250-watt blue Photoflood lamps. This minimizes the post-processing time and effort- a few minor tweaks will usually balance the indoor/outdoor colour temperatures. The Blue photofloods are usually a bit warmer than daylight but I find that effect is acceptable.

In the attached image, the daylight is the main source and a bit of bounced Speedlight fills the shadows. The warm quality and mood of the late afternoon sunlight was maintained by adjusting the flash illumination to 2 stop below the ambient light.

Exposure wise, I can usually balance exterior exposure with indoor exposure. In some cases, you can expose for the flash and adjust the shutter speed to arrive at the proper exposure for the exterior light level without burning out the windows and manage to do it all in one shot.

In a controlled situation where there is time to set up multiple lights and even place flash units outside to simulate window light,t there are more possibilities. When, however, such as while travelling to tourist attractions, museums, etc., or on a low-budget real-estate shoot, this method is more practical and workable and you can still inject mood and atmosphere into the shot.