Metering Stained Glass Windows, mixed w/Tungsten

[John Sarsgard]

I'm going to be photographing some large stained glass windows, mostly by transmitted light. The church interior will also be lighted at the time, with of course tungsten lighting. I'll be using negative film, my old favorite Portra 400NC, in 4x5. Is this any more sophisticated a problem than just taking lots of spot meter readings and averaging them off the windows? Don't know how much the interior light will affect the exposure, but can always fix a cast later, since it's negative film. Thanks.

[Jack Flesher]

I think you'll find if you place the windows between zone 6 and 6-2/3 you'll get the best results.

[Ralph Barker]

I think you're looking at two separate problems, John. First is the exposure balance between the lighted interior and the outdoor light transmitted through the stained glass windows. Second is the different color temps of the two light sources, and whether (along with how, and to what extent) you might want to correct the interior color temp.

Although I haven't done a similar shot recently, my sense is that Jack's suggestion of where to "place" the windows is probably pretty close. To balance the interior exposure, you may find that supplementing the interior lights with soft, bounced electronic flash will help - both in terms of exposure balance and controlling the warmth of the interior tungsten lights. As with other mixed lighting situations, use the f-stop to control the flash contribution to the exposure, and shutter speed for ambient light exposure control.

Although you could use color correction filters to correct the interior tungsten light to the daylight color balance of the film, that would also shift the windows farther toward the blue end of the spectrum 0 a result that may not be pleasing. Plus, some degree of warmth (yellowish) for the interior lighting may be appropriate or desireable.

[Henry Ambrose]

John, if you are interested in the windows -only- your idea of spot metering and averaging will do the job. If the window -and- its surroundings are the subject of your photo then it becomes a bit more complicated. You will probably need to add some light to bring the window casing, moldings and walls up a bit. Or you might be able to time your picture so that the exterior and interior light levels are close enough to render on film as you envision. But its likely that you won't have much time to shoot as the peak combination won't last long.


Click here (opens in new window) and click on the sixth photo down the scroll bar to see an example of lighting to bring the interior up to the window illumination. If I remember correctly its several "pops" of a flash with umbrella combined with a 30 second exposure.

[Ralph]

It's too bad you can't turn the lights out inside the church; that would completely solve the problem. Photographs of "just" stained glass (looking out, I mean) are never helped by interior lighting, but I assume that you have to photograph the windows in the context of the church interior and thus have to have the church lights on.

[Louie Powell]

John -

I've done this. It's a challenge, but it can also be fun to figure out how to balance everything.

There are two major issues. The first is the exposure, while the second is color balance.

I suggest studying the lighting carefully - and taking lots of notes. Use a spot meter so that you can get localized measurements. Don't worry too much about the shadows in corners, but concentrate on the areas that are important in the image.

I found that to balance exposure between the windows, interior light sources (which were unavoidably within the image frame), and the areas that were illuminated by these two sources, I had to do a complex series of multiple exposures on the same frame of film. I started with an exposure for the area with the brightest highlights. Then, I turned off the light responsible for those highlights, and did some additional exposures, progressively turning off llights, until I got to a final exposure with only ambient light through the stained glass windows.

If you find that your windows themselves are the brightest highlights, you face a slightly different challenge. One solution to that is to do one exposure during daylight, and then come back after dark to do additional exposures (equivalent to "turning off" the daylight source behind the windows). Alternatively, you can experiment with adding light to the interior space using a painting-by-light technique.

The answer to the color balance issue really depends on the dominant source of lights. I suspect that you will probably want to use tungsten film to give a reasonable interpretation of the interior light. Daylight normally has a very cool blue cast on tungsten film, but the daylight coming through the stained glass windows will be "filtered" by the glass, and it will probably be OK on tungsten film. The only problem will be if you have areas of the windows that are white - these will allow "unfiltered" daylight into the scene to give you that blue cast. I had one instance (photographing a pink marble staircase by interior tungsten light) when a few highlights caused by daylight through a nearby doorway provided an attractive contrast. If these are too large, then you either have to add filtration (you can purchase large sheets of filtration material that can be attached on the outside of the offending windows), or else you have to use the multiple-exposure technique (one exposure during the daytime for daylight, and the rest after dark for the interior lights) with a filter on the lens of the camera when exposing for the daylight.

In one case I also had to deal with some fluorescent light in the mix. In that instance, I simply turned off the fluorescent for all but one of the series of multiple exposures. I used filter on the lens for the one exposure in which I turned on only the fluorescent lights - I didn't have a filter that was the correct match for tungsten film and fluorescents, but what I had was close enough in the overall mix of lighting.

[Walt Calahan]

I recently had to photograph stained glass windows in a Baltimore church. Used daylight balanced color negative film to get the best color out of the glass. Turned off all the fluorescent lights but left the tungsten lights on.

The results were beautiful glass (set at around zone 6 as mentioned in a previous post), with the interior detail of the church walls having a nice warm feeling, but not too warm because the daylight coming through the windows cools the tungsten light down naturally.

Use a good tripod and you're home free.

[GPS]

Be glad if you have interior lights on - they are necessary to illuminate the lead pieces holding the individual glass pieces together. If you have the final picture with black bars (because underexposed) separating the stainned glass it will look like a picture behind bars - very annoying. You need fill in light from the interior - it doesn't take away the effect of illuminated windows, it helps to "read "them.

[Terence Spross]

I've done this also

In terms of adding lighting in one situation, flash or flood from the floor level would add shadows that would not be normal considering the architechure with beams etc.

The afternoon light was too bright for the transmission thru the stained glass relative to the interior light, so I simply waited to later in the day when the light from the windows was less and proportioned well with the interior light. An overcast sky helped balence the N.East windows with the S.West windows.

If shooting at a different time had not been possible, I would have tried my narrow beam flash, (a special powerful flash I built origionally for use with a 400mm lens on a 35mm camera, and have since used it in other situations). I would have aimed it straight up to the church ceiling to avoid unnatural shadows. Or if I had access to the balcony, I could have used a more normal remote triggered flash from there, with the camera positioned on the floor for the desired shot.

[Kirk Gittings]

If the final product is a file, I would take a different approach.

Wait till time of day when light is not coming directly through the glass.

Boost interior light some with additional tunsten or halogen.

Shoot two daylight color negatives.

One for glass as Jack mentioned above, and one for interior. Don't move the camera in between and adjust exposure only with the shutter speed.

Process film normally.

Scan and adjust color balance as needed, and paste "window exposure" behind "interior exposure" and paint the "we" windows into the interior scene.

We do this all the time (a couple of times a month) for magazines these days. It gives us a much more natural look than having to blast light into the interior to bring it up to the window's level of illumination.