READ & COMPREHEND
CH. 4 EXPOSURE p. 65-67
CH. 5 DEVELOPING p. 94-97
CH. 6 PRINTING p. 101-109
VOCAB! ENLARGER PARTS AND DARKROOM ETIQUETTE
That’s not the point of this blog post.
Here I am, at 8:37 am, the day before the quiz, and like any self-respecting college student, I haven’t read a single word of this crap. I can’t even remember what the “Enlarger” is called – I just keep calling it “the darkroom machine thingy,” and can’t figure out why knowing what the parts are called is important as long as you know what the yellow knob on the left does and you don’t open the slot with the light and fog up someone’s shit.
I guess this post is going to be about taking notes.
There was supposed to be a post before this one about pinhole cameras and exposure, but it didn’t happen.
There’s supposed to be time for me to do my math homework and read 30 children’s books and analyze them for my Children’s Literature Analysis Class today, too.
I don’t even know what this side of 9 am looks like on a normal day. My photo class isn’t until 3:30 pm.
Dr. Pepper, get me through this. And someone grab me some breakfast. I have some reading to do.
Notes to follow. Most of this will be verbatim from the 8th Edition of “A Short Course in Photography” and probably won’t be cited properly. I’m not trying to plagiarize, I’m just trying to take notes, not write an essay here.
Chapter 4: Exposure
Exposing your pictures correctly (that is, setting the shutter speed and aperature so they let in the correct amount of light for your scene & a given film or sensor) makes a big difference if you want a rich image with realistic tones, dark but detailed shadows, and bright, delicate highlights instead of a too dark, murky picture or a picture that is barely visible because it is too light.
(Note to self, stop flipping through the book and looking at other shit)
Making a correct exposure, letting the right amount of light into the camera, involves understanding just three things:
- How the shutter speed and the size of the lens opening (the aperture) work together to control light (see p. 18-23)
- The sensitivity of your film or digital sensor to light. Film speed (p. 57-57) is usually expressed as an ISO rating. With a digital camera you choose an ISO rating to set into the camera.
- How to measure the amount of light and then set the exposure, either automatically or manually (p. 68-79)
Wow, I sure am glad we’ve covered these 3 easy steps in other readings or discussions in class! Actually, okay, we have discussed the first one, but not really the other two. I should probably look those up.
p. 18. Shutter Speed Affects Light & Motion.
To make a correct exposure so that your picture is not too dark or too light, you need to control the amount of light that reaches your sensor/film. The shutter speed (amount of time the shutter remains open) is 1 of 2 controls your camera has over the amount of light. The aperture size (p. 20) is the other.
In addition to controlling the amount of light that enters the camera, the shutter speed also affects the way that moving objects are shown. A fast shutter speed can freeze motion – 1/250th sec. is more than fast enough for most scenes. A very slow shutter speed will record even a slow moving object with some blur. The important factor is how much the image actually moves across the recording surface. the more of the surface that it crosses while the shutter is open, the more the image will be blurred, so the shutter speed needed to freeze motion depends, in part, on the direction in which the subject is moving in relation to the camera.
How far your subject is from your camera is important too. The lens focal length and the distance of the subject fromm the camera also affect the size of the image on the sensor/film & thus how much it will blur. A subject will be enlarged if it is photographed with a long-focal-length lens or if it is close to the camera; it has to move only a little before its image crosses enough of the recording surface to be blurred.
Speed of motion is also important. A darting swallow needs a faster shutter speed than a hovering hawk but even a fast-moving subject may have a peak in its movement – when the motion slows just before it reverses. A gymnast at the height of a jump or a motorcycle negotiating a sharp curve is moving slower than at other times and so can be be sharply photographed at a relatively slow shutter speed.
Here’s a handy image that talks about shutter speed and how it appears in the viewfinder or on the dial of a camera.
Important things to note: Only the bottom number of the fraction is shown (ie: in 1/250th sec. you see 250 on the dial). Shutter speed settings are in fractions of a second. Ech setting lets in twice as much light as the enxt faster setting, half as much as the next slwer setting. (ie: 1/250 sec lets in 2x as much light as 1/500 sec, half as much as 1/125 sec.)
Slow shutter speed, subject blurred.
The direction a subject is moving in relation to the camera can affect the sharpness of the picture. At a slow shutter speed, a driver moving from right to left is not sharp.
Fast shutter speed, subject sharp.
Photographed at a faster shutter speed, the same driver moving in the same direction is sharp. During the shorter exposure, her image did not cross enough of the recording surface to blur.
Slow shutter speed, subject sharp.
Here the driver is sharp, even though she is being photographed at the slower shutter speed that recorded blur int eh first picture. She was moving directly toward the camera, so her image did not cross enough of the recording surface to blur. The other go-kart, turning to move across the frame, becomes blurred.
(In this instance, it helps for me, as a gamer, to think about doing something like trying to shoot a deer in Skyrim. If the deer is running toward or away from me, it is easier to hit it with an arrow than if it is running sideways and I have to try to project where it will be by the time the arrow reaches it!)
Panning with the vehicle is another way tot keep it and the driver relatively sharp. During the exposure, the photographer moved the camera in the same direction tat the go-kar twas moving. Notice the streaky look of the background, characteristic of a panned shot.
Remember, freezing motion is one way of representing it, but it sometimes eliminates the feeling of movement altogether so that the subject seems to be at rest. Allowing the subject to blur can be a graphic means of showing that it is moving.
Affects Light & Depth of Field (p. 20)
In class, we talked about apertures being like turning on and off the water faucet – how high you turn the water is how open your aperture is – how fast the water fills the glass (or how fast the light gets in to your camera/film/sensor) depends on how high you turn the water on (how open your aperture is). You can fill the same glass quickly or more slowly with a larger or smaller aperture (respectively).
The Aperture, or lens opening, is the other control that you can use in addition to shutter speed to adjust the amount of light that reaches the film/sensor. Turning a ring on the outside of the lens changes the size of the diaphragm, a ring of overlapping metal leaves inside the lens. Like the iris of your eye, the diaphragm can get larger (open up) to let more light in; it can get smaller (stop down) to decrease the amount of light.
The size of the lens opening (aperture or f-stop) controls the amount of light that passes through the lens. Each aperture is one “stop” from the next; that is, each lets in twice as much light as the next smaller opening, half as much lgiht as the next larger oepning. Notice that the lower the f-stop number, the wider the lens opening and the more light that is let in. (ie: f/8 is wider and lets in more light than f/11, which lets in more light than does f/16 and so on.)
Referring to a stop is a shorthand way of stating this half-or-double relationship. You can give one stop more (twice as much) exposure by setting the aperture to its next wider opening. You can give one stop less (half as much) exposure by stopping (closing) down the aperture to its next smaller opening.
The size of the aperture setting also affects how much of the image will be sharp. This is known as the depth of field. As the aperture opening gets smaller, the depth of field increases and ore of the scene from near to far appears sharp in the photograph. (There is a depth of field project on p. 185 that I’ll probably look at later).
Small Aperture, More depth of field
Bottom: Large Aperture, Less depth of field
Depth of field and the aperture.
The smaller the aperture opening, the greater the depth of field. At f/16 (top) with the hands and string int he foreground crisply in focus, the face in the background is also sharp. At a much larger aperture, f/1.4 (bottom), there is very little depth of field. The face in the background is completely out of focus.
Short Course in Photography, p. 21
Barbara London & Jim Stone (like everything else quoted in this blog post.
Shutter Speed & Aperture
blur vs depth of field
Both shutter speed & aperture affect the amount of light. You need to find a combo of shutter speed & aperture that will let in the right amount of light for a particular scene (see p. 65-81)
Once you know a correct combo of shutter speed & aperture, you can change 1 setting & still keep the exposure the same as long as you change the other setting the same amount in the opposite direction. (Smaller aperture (less light) slower shutter speed (lets in more light))
Which combo to choose – you decide based on what you’re shooting. Is stopped motion more important, or depth of field?
There’s a good series of pictures illustrating this on pages 22 & 23, but I’m short on time and patience, so i might add it to this post later, but here’s a basic breakdown.
1/500 sec (fast shutter speed) & f/2 (wide aperture) -> moving swing is sharp, trees, picinic table & person in the bg are out ot focus. only objects the same distance as the foreground posts on which the lens was focused are sharp.
1/60 sec (medium-fast shutter speed & f/5.6 (medium-wide aperture) -> moving swing shows some blur. bg is still a little fuzzy but middle ground appears in focus.
1/8 sec (slow shutter speed) & f/16 (small aperture) -> moving swing is completely blurred, middle-and-background are completely sharp.
p. 56 & 57 — Film Speed & Grain — the 2 go together.
How sensitive a film is to light – that is – how much it reacts to a given quality of light is indicated by its film speed. the more sensitive – or faster – the film, the higher its number in the rating system.
A high film speed is often useful: the faster the film, the less exposure it needs to produce an image. Fast films are often used for photographing in dim light or when a fast shutter speed is important. But along with fast film speed go some other characteristics: most important, an increase in graininess, plus some decrease in contrast and loss of sharpness. With color films, there is also a loss of color accuracy and saturation.
Ideally, for max sharpness, you should choose the slowest film usable in a given situation – for pratical purposes, however, most photographers load a medium speed (ISO 100) film for general use. A higher-speed (ISO 400) film will be their choice for dimly lit subjects or those requiring high shutter speeds.
Some people like grain. Use it for artistic effect.
Certain films have reduced graininess (Kodak T-Max or Ilford Delta) The shape of their silver crystals makes them more sensitive to light but without a corresponding increase in grain. A caution: Follow processing instructions carefully. Even a slight increase in time, temperature or agitation during development may cause a distinct increase in film contrast. Although for example Kodak Tri-X (ISO 400) is grainier than T-Max 400 (same film speed), Tri-X and other standard ISO 400 films continue to be used because they are easier to control with ordinary darkroom processing and because they record tones differently, in a way that some photographers prefer. Black-and-white films based on color technology (see p. 58) also offer reduced graininess.
Exposure determines the lightness or darkness of an image.
Film & Paper have exposure latitude; that is, you can often make a good print from a less–than-perfect negative. Color slides have the least latitude. (p. 62) For best results, don’t overexpose or underexpose them for more than 1/2 stop. B&w or color prints can be made from negatives that vary somewhat more: from about 1 stop under exposure to 2 stops over exposure is usually acceptable. (more on stops & exposure on p. 70)
with too much variation from the correct exposure, prints & slides begin to look bad. too much light overexposes a negative. it will be much too dense with silver to pass enough light tot he printing paper, resulting in a final print that will be too pale. Conversely, too little exposure produces a negative that is underexposed and too thin, resulting in a print that is too dark. the results are similar with color slides.
How Chemicals Affect Film
Developers chemicals take the film to its next step, exposing the latent image and converting the exposed crystals of silver halide in the film emulsion to visible metallic silver. The active ingredient in the developer is the reducing agent. Metol and hydroquinone, usually used in combination are 2 common reducers. other chemicals enhance the action of the reducer. Most reducers work only in an alkaline solution. This is provided by the accelerator, an alkaline salt such as borax or sodium carbonate. Some reducers are so active that they can develop the unexposed as well as the exposed parts of the film, fogging the film with unwanted silver. To prevent this, a restrainer, usually a potassium bromide is added to some developers. A preservative, such as sodium sulfate, prevents oxidation and premature deterioration of the developer solution.
Developer times & temperatures are critical.
The stop bath is a simple acid solution (sometimes plain water is used) that neutralizes and partially removes the alkaline developer. Fixer is also acidic, so use of an acid stop bath helps extend the life of the fixer.
Fixer makes the image permanent by dissolving out of the emulation any undeveloped crystals of silver halide. These are still sensitive to light and, if exposed, would darken the negative overall. This is why the cover must stay on the developing tank until well into the fixing stage of development (step 17, p. 91). Once the fixing is complete, a permanent image of metallic silver remains. Fixer time is not as critical as developer time, but the film should not be underfixed or overfixed so follow the time limits set by the manufacturer.
Washing removes chemicals left in the film after fixing such as sulfur compounds that can damage the image if allowed to remain. Simple immersion in running water will wash the film, but treatment with a clearing bath speeds up the process and does a better job than using water alone, leaving the film as permanent as possible.
Fresh solutions are vital. Chemicals gradually deteriorate, particularly once they are diluted to working strength with water and exposed to air. processing film in exhausted chemicals can produce stains, fading images, uneven development or no image at all. When you store chemical solutions for future use, keep a written record of the date you mixed the solution and how many rolls of film you processed with it. Don’t store chemicals longer than the manufacturer recommends or try to use them to process more rolls of film than rec’d.
P. 97 – Evaluating your Negatives.
Expose for the shadows, develop for the highlights.
The longer the development time (at a given temp.) the denser & darker a negative will be, but that density does not increase uniformly over the entire negative. The density of a white wall increases quickly, a gray rock, at a moderate rate and a deeply shaded area changes v. slowly. Increasing development time increases contrast.
If you frequently have trouble getting enough detail in darker parts of your prints, try giving your negatives more exposure by resetting the film sped dial to a sped lower thn that rec’d by the film manufacturer or by bracketing to give the film extra exposure.
Follow rec’d development times exactly at first. You can change your development times if you find that roll after roll of your negatives are difficult to print — if they are often high in contrast so you print most negatives on a low-contrast paper, try decreasing the development time 20-30%. If negatives are often low in contrast, try increasing time 25-40%.
You can change development for individual scenes. If you think a scene at dusk or on an overcast day with little difference between highlights & shadows may be be too flat, try increasing the development time by 50%. With foll film, changing the development time affects the entire roll, so it’s best to shoot the whole roll under the same conditions.
Printing in a Dark Room (p. 101)
Think of your darkroom as having dry side and a wt side; you will be moving repeatedly from 1 side to the other. On the dry side, you handle negatives, adjust the enlarger & expose paper. On the wet side, you mix chemicals & process prints. it is vital to prevent wet-side procedures from contaminating the dry side. Even a small amount of a chemical staying over the the dry side on your fingertips, even if you wiped them, can leave fingerprints on your next print, permanently damage negatives and more. (see p. 86 for how to avoid contamination, mix chemicals & handle them safely)
p. 102 & 103 has an image of the enlarger and definitions of terms relating to the enlarger. Really important stuff.
Making a Contact Print. (p. 104)
A contact print is mad with the negative in contact witht he printing paper; the print is the same size as the negative. A contact sheet of al the negatives on a roll makes it possible to examine & compare different frames so you can choose the ones to enlarge. Then you can store the contact for later reference.
It is useful to have a contact sheet for each roll or negative storage page. Store them seperately so that handling your contact sheets doesn’t pose the risk of damage to your negatives. Contact prints of 35mm natives are to small to evaluate each image ctitically but hey do give you a 1st look at exposure, lighting, sharpness & other factors. And the back of the contact print gives you a convinent place to keep dates, places, names, & other notes about the photographs.
A 36-exposure roll of 35mm film will fit on an 8×10 inch sheet of printing paperr. Use a grade 2 or normal contrast paper. (Contrast grades are explained on p. 117)
1. Position the Enlarger: Insert an empty negative carrier in the enlarger head & close the slot where it is inserted so that light will shine only on the basebord and is not coming out of the slot, This is particuarly important in a group darkrom bc stray light can fog other people’s prints. Using an empty carrier ensures even illumination. Switch on the enlarger lamp. Place the negatives & the glass or printing frame on the enlarger baseboard. Rise the enlarger head until the light covers the entire glass.
2. Set he lens aperture & the enlarger timer
As a trial exposure, set the enlarger lens aperture to f/8 and the timer to 5 sec. you amy want to change these settings after eveloping & evaluating the prints (see step 6). You can, if you wish, make a test print, using a range of idfferent exposures, as described on p. 112.
3. Identify the emulsion sides of the negatives and paper
The negative emulsion must face the paper emulsion or prints will be reverse left to right. Film tends to curl toward its emulsion side which is usually duller than the backing side. You are loking at the emulsion if the frame numbers on the end of the film read backward.
Turn on the darkroom safelights and TURN OFF THE ROOM LIGHTS AND ENLARGER LAMP before opening the package of paper. The emulsion side of the paper is shinier and with glossy papers, smoother than the back side. Fiber-base paper curls toward the emulsion side; RC paper curls much less and may curl in either direction, but may ave a visible manufacturer’s imprint on the back side.
4. Insert the negatives and one sheet of paper under the glass
The paper goes emulsion side up. The negatives go above the paper, emulsion side down. The glass sandwiches the negatives & paper together tightly. The easel shown here helps locate the glass exactly but you can simply put the paper on the enlarger baseboard with the negatives on top then cover them with a plain sheet of glass.
To make contact prints, you can leave negatives in their plastic storage pages or remove them. The contact print through the plastic will not be quite as sharp, but leaving them in the page minimizes handling and protects them from accidental damage. Unfortunately, and entire 36-exposure roll won’t fit on an 8×10 sheet if the film is in a storage page.
5. Expose and process the print
With the printing frame in place under the enlarger head, push the timer button to turn the enlarger light on and expose the print.
Process the paper as shown on p. 106-108.
After fixing, evaluate the print in room light. Carry it in an extra tray so fixer doesn’t drip on other surfaces.
6. Evaluate the print
Some of the frames will be lighter, others darker, depending on the exposure each received int he camera. To judge print exposure overall, examine the film edges in the print they should be black but with the edge numbers legible and with 35mm film, a very slight difference between the edges and the darker sprocket holes. If the edges of the film look gray, many frames will probably be very light; make another print with the enlarger lens opened to the next larger aperture. If the edges of the film are so dark that you can’t see edge numbers or sprocket holes, many frames will probably be very dark. Close the enlarger lens to the next smaller aperture for the next print.
There’s anotehr section about processing prints that doesn’t make sense because I don’t understand how we got from tiny little negatives to big prints and I need to understand that for the printing process to actually make sense to me. I hope that’s not on the test. I’ll go over that later.