CORRECT EXPOSURE

Q: What is correct exposure?
A: It’s what you the photographer determine it to be!

Rarely do I shoot what I would consider a “record” shot in which I worry about accurately capturing what I see in front of my lens if I’m out shooting with the intent of pushing my slide film into reciprocity failure (RF). However, as a result of testing a 3 stop screw-in Neutral Density (ND) filter a couple of weeks ago while I was shooting the St Joseph lighthouse late in the evening I did end up with an image that gave me the reciprocity failure I was looking for and another that pretty much accurately recorded what the light was really like at the time I was shooting.

Before going there, The other “stuff” I shot that evening wasn’t too bad either color-wise. This time of year, at St. Joe’s the sun is still setting sufficiently far south that the angle of the North Pier on which the inner and outer lights sit is such that the sun sets between the inner light and shore. That reminds me, I want to get some sunset shots at St Joe’s with the sun setting between the two lights so next weekend, if the weather guy cooperates, off to St Joe for the sunset one evening.

The night that all of these shots were taken, there were some interesting clouds in the sky that had the potential for an interesting sunset.



This shot was taken set up at near the water’s edge, and I’m not at all bashful about setting up one of my tripods IN the lake or the ocean for that matter, as the rust on my poor old Bogen will attest to from having been set up in the ocean to shoot Cape Hatteras a few times. In this particular case, my choice of where I set the tripod was predicated by the wet sand afforded by the small waves lapping the shore that would serve as a reflector for sunset color, drawing some color and interest into the foreground of the image.

Exposure data:
Film – Fuji Provia 100F professional slide film
Camera body – Nikon F5 (so Paul can recognize me) and a Nikon MC-20 digital cable release.
Lens – Nikkor 24-120 mm zoom at 60 mm
Aperature - f5
Shutter speed 1/30th sec

I was primarily concerned with a shutter speed sufficiently fast to keep the waves distinct as waves and adjusted the aperature accordingly after deciding that I’d use 1/30th sec. When those choices are behind you, it’s simply a matter of waiting until the sun has set to where you want it to afford the color you’re looking for, then waiting for a wave to give you a good wetting of the sand so it acts as a reflector. I think I ended up shooting four or five frames with that camera positioning before moving on to other things.

I frequently shoot until it’s totally dark! This next shot is a about how dark it usually gets before I quit when I’m out at the lake with my cameras.



This particular shot was taken with a 300 mm f4 lens wide open at f4 with a 90 sec exposure and a 3 stop ND screw-in on the front of the lens to pretty accurately reflect how dark it was. This image, dark as it is, technically represents CORRECT EXPOSURE the subject of this particular thread! Trust me, this wasn’t what I was looking for that evening.

Rather than the above “correctly exposed” image, I was playing with reciprocity failure, which is one of my frequent low light pursuits. The photograph below was taken just before the one above but using a 60 sec exposure, again with the 300 mm f4 lens at f4 but without the 3 stop ND screw-in filter. Both Provia 100F that I was using and Fuji Velvia are in reciprocity failure with exposures beyond 30 or 40 sec. This one is no exception… the lake wasn’t that iridescent shade of blue to be sure (unless the nuclear power plant 20 miles up the coast was leaking something funky into the lake!) To make this look “correct” you’d have to expose for about 2 ½ to 3 ½ times as long as the metered exposure. As I’ve already said, that would give you something that looks like the shot above generated with a 3 stop ND filter.



Which of these two exposures is correct? Technically, the first of the two that looks like midnight on a moonless night! I personally prefer the second, because that was the sort of effect that I was looking to create that night with my camera. The bottom line is that it’s up to you as the photographer to decide what is correct.

GARY



[This message has been edited by lighthouse_photo (edited 02-24-2002).]

Looking forward to reading what else you have to offer us for information, Gary!

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Terry (Only my mother, brothers & sisters call me Teresa) Forrest

It's a comin'

Gary

Getting the exposure 'correct' on sunsets and sunrises ain't easy. Especially if you have a camera with an internal metering system.

This metering system wants to assume that every picture (without a flash) was taken during mid-day.

So the setting sun overpowers the metering system which wants to 'darken' that bright spot thus underexposing what you see.

Or if the sun has snuck over the horizon and no longer overpowers the meter, the result may be an image that is brighter than you see.

One trick is to aim the camera at an adjacent part of the sky - the open sky to get the exposure. Then either use your exposure lock or switch to manual and use the settings you saw from the adjacent sky.

Recompose the sunset or sunrise and take your image. Then bracket either side.

Turn off your autofocus and set the focus manually at infinity. Sometimes bright light prohibits automatic focus cameras from focusing properly. The sun is always at infinity so that's one less thing to worry about.


[This message has been edited by JChidester (edited 02-18-2002).]

John has made some good points here.

The sun, if it's in your viewfinder is the kiss of death in terms of getting the exposure correct! Remember that the metering system is going to make the sun 18% grey rather than a bright light source! As a consequence, as John has correctly noted, everything else is going to get pretty gloomy, which is hardly what you want for vibrant sunset color! If you meter away from the sun - this is a good time to use center weighted or spot metering settings if your camera has them - you'll get a meter reading that is appropriate. Remember, you want that area that you're using for metering purposes to be a middle tone... like medium orange. Recompose and shoot without readjusting the meter, which will go quite high... probably about +2 to 2 1/2 stops, which is where it should be.

Another thing about the sun in your viewfinder - you're going to get lens flare. This is the little geometric shapes that you see radiating from the light source in an image.. they might be pentagons, hexagons, or perhaps even heptagons.....

********* VERY IMPORTANT **************

REMEMBER NOT TO STARE THROUGH YOUR VIEWFINDER WHEN THE SUN IS VISIBLE THROUGH IT ESPECIALLY IF YOU'RE USING A TELEPHOTO. YOU CAN PERMANENTLY DAMAGE YOUR RETINA!!!!!

***************************************

The photo shot at dawn at the Sturgeon Bay North Pierhead light below has the sun behind some clouds out over Lake Michigan. This was shot at the meter or perhaps 1/3 stop (also referred to as 1/3 EV) over exposed to brighten the sun and the yellows some.



John's comment on braketing is worth a tiny further comment. For anyone who doesn't know what he means, shoot your recomposed scene at the settings you just established with the metering exercise that John and I are suggesting. Braketing corresponds to intentionally over and under exposing. There are 2 ways to do this: you can adjust either the shutter speed or the aperature. For the shutter speed, take one exposure with the shutter set to the next higher setting and a second to the next lower setting from where you took the first. For an aperature adjustment, do the same, one with it opened wider one step and one closed by the same amount. The age of your camera will determine how much of a change the shutter speed or aperature readjustments are. For older cameras, you'll probably be exposing +/- 1 stop of light. Newer cameras will allow you to make an adjustment of +/- 1/2 or even 1/3 of a stop. Something between 1/2 and 1 stop is what you'd normallly want, so if you have 1/3 stop settings, it's probably best to bracket by a total of +/- 2/3 of a stop.

AUTOFOCUS

John has made another good point here. The sun will mess with your camera's autofocus mind, as will very low light conditions. I differ a little from John, however on where to park your focus when you move the camera to manual focus. I focus on the lighthouse if there's one in the frame. That will be my primary subject and I always want to make sure that it is in sharp focus. With the aperatures that I typically use (see below) having infinity in focus usually isn't a problem.

PRINTS vs SLIDES

If you're shooting print film, you've got more exposure latitude than you do with slide film. Prints will generally allow you to be off by as much as +/- 1 1/2 to 2 full stops of light. Slide film is much less forgiving and you're generally well advised to be within +/- 1/2 to 2/3 of a stop.

APERATURE

When I'm shooting sunrise/sunset photos, I always shoot with my lens stopped all the way down to it smallest aperature. On most lenses this will be f22 but I have a couple that will go to f32 and one that goes down to f40. This lengthens your exposure time considerably, but correspondingly gives you much better color saturation on slide film, which all that I shoot. Tripods with small aperatues and long exposure times become a must as does a cable release or the use of your camera's self-timer!!!

I hope some of these ideas are helpful. The way I go about photography works for me but there are other equally valid ways about setting up exposures, choices of aperatures, etc. If anyone has questions or other ideas on any of these topics, feel free to jump in and forward those ideas. That's what this forum is for!!!!!

Gary

Thus far in this thread, although I briefly mentioned Reciprocity Failure (RF) and posted one shot that has it, I haven't really discussed it much as yet. I'll add that in a day or two. I'm traveling on business to give a scientific lecture the next two days so you probably won't see this until Thursday night at the earliest!

Gary

My experiences with print film, having used it from age 18 up to Sept. 2001 at age 57-1/2, are that as much as you have more latitude shooting it, it also means that the photo lab that develops your film has more latitude. This doesn't always mean that they're going to print your developed prints in the true colors of what was actually there when you took your photo(s), nor does it mean even if you return to the same place for reprints or enlargements that you're going to get the same colors as what they originally did. I can't tell you the countless number of times through the years when I was using print film when the colors in enlargements were so totally different from the original developed prints as to seem like totally different photos, often times worse than the original developed prints. The same things or worse can happen when you have reprints or enlargements done at different photo labs than where the originals were done. In addition, print film is grainier, if I remember correctly, and if you're like more people nowadays and are into going digital with your photos, whether you're having them scanned onto 3-1/2" floppy disks or cds during the original development process or scanning your negatives or prints yourself onto floppies, cds or your computer's hard drive, you're more apt to get what is called digital noise in your end results, which when shown on a computer monitor, doesn't make for an appealing photo.

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Terry (Only my mother, brothers & sisters call me Teresa) Forrest

[This message has been edited by 1of3trees@prodigy.net (edited 02-19-2002).]