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Cinematography FAQ


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Administrator Note: It's been a while since this post was updated. It was created when this forum was new. The intention was to update this post regularly so that new forum visitors could find answers to the most common questions asked. It does not address new technologies but it is by all means worth reading.

 

 

 

FAQ WORK IN PROGRESS

1. What is a cinematographer? What do they do?

The simple answer is that the cinematographer (also called the ?director of photography?) is responsible for the photography of a motion picture, but that job entails so much more than photography. Quoting the definition given by John Hora, ASC in the ASC Manual:

"Cinematography is a creative and interpretive process that culminates in the authorship of an original work of art rather than the simple recording of a physical event. Cinematography is not a subcategory of photography. Rather, photography is but one craft that the cinematographer uses in addition to other physical, organizational, managerial, interpretive and image-manipulating techniques to effect one coherent process. These visual images for the cinema, extending from conception and preproduction through postproduction to the ultimate presentation and all processes that may affect these images, are the direct responsibility and interest of the cinematographer.?

On a typical movie set, the cinematographer has three departments under their supervision to aid in the photography: Camera, Electric, and Grip. Each department has their own key supervisor.

On smaller productions, the cinematographer is also often the camera operator.

2. What is a skip-bleach / bleach-bypass / ENR process?

These are all forms of SILVER RETENTION processing.

In color photography, just as in b&w photography, silver halide grains reacts to light, making them developable into silver later in processing. Unexposed grains remain as silver halide, which in b&w processing, would get removed in the fixer and wash steps, leaving only silver.

However, with color photography, color dyes are formed in each layer in equal amounts to the silver formed. Then in the bleach step, the developed silver is converted into silver halide, so that later in the fixer and wash steps, all the silver halide is removed, leaving only color dyes. If the bleach step is skipped (i.e. bleach-bypass or skip-bleach processing), then the developed silver remains mixed with the color dye that developed, ?polluting? each color with black silver. This increases the contrast and reduces the color saturation.

When the skip-bleach processing is done to the negative, where the scene highlights are represented by the densist areas, leaving the silver in mainly increases the contrast in the highlights, causing them to burn out faster, and increasing density in general as if the film had been overexposed or overdeveloped. To compensate, people will sometimes underexpose the negative by one stop to bring the density back down to something normal.

When the skip-bleach is done to the print, where the shadow regions of the scene are represented by the greatest amount of density, leaving the silver in mainly increases the contrast in the shadows, causing them to lose detail faster, and making the blacks very deep. The D-max of the print stock goes up because blacks are made up of both dye and additional silver.

3. What is cross-processing?

It usually refers to processing color reversal film in a color negative bath so that a negative results rather than a positive. The results will be missing the brick-orange color mask, have very intense colors but with inaccurate hues, high contrast, and increased graininess. Often there is a greenish bias to the image.

4. What happens when you push / pull the processing of film?

5. Why do some DP?s overexpose a film stock , i.e. rate it at a slower speed than recommended by the manufacturer? How should I rate a film stock?


The Exposure Index (E.I.) value that the manufacturer gives a film stock is only a recommended starting point, fairly conservative, designed to place a wide range of scenic exposure values within the range that the emulsion can record information. It should give you a negative, when processed normally, of average density that will create a good image when printed with decent blacks, whites, and midtones.

Some mild overexposure can improve the look of the printed image however. Overexposure allows more of the slower, smaller grains to become developable, which in turn ?tightens? the grain structure of the image, making it look less grainy. Also, a slightly dense negative printed ?down? (printed using higher printer light numbers) will make blacks deeper, which gives the image the impression of richer colors and more contrast and sharpness (?snap?.) Generally no more than 2/3?s of a stop overexposure, maybe even one stop, is needed because at some point, you?d get better results just switching to the next slower-speed stock. Plus excessive overexposure places too much highlight information on the shoulder of the characteristic curve, which is flatter (has less contrast), with some high-end information being too overexposed to record any detail.

The E.I. value is also referred to as the ASA (American Standards Association) or ISO (International Standards Organization) value; these are older, obsolete terms but still commonly used.

6. What is reversal film?

A camera film stock that when exposed and processed, produces a positive image for direct viewing rather than a negative image.

7. What is the visual difference between the Kodak and Fuji film stocks?

When comparing the ?normal? contrast line of color negative stocks made by the two companies, the differences are now smaller than they used to be. For projects going directly to standard-definition video, it may so subtle for some as to not make much of a difference. The Fuji stocks, when compared to those of a similar speed in the Kodak line, may look slightly softer and grainier. They seem to shift a little to the green when severely underexposed. In 35mm, this is a pretty small difference but in Super-16, it may be more of a technical issue to consider when choosing stocks. The Fuji palette, however, may be something that works well for a particular project, especially in 35mm where grain & sharpness are less critical than in Super-16. Fuji has a 400 E.I. low-contrast negative stock that is similar to Kodak Expression 500T. It is also softer and more pastel than the Expression stock. Fuji also has a 500 E.I. daylight-balanced stock for which there is no Kodak equivalent; however, Kodak?s 250 E.I. daylight-balanced stock (52/7205) would probably push very well to 500 E.I., but the results would be more contrasty than Fuji F-500D.

8. How do I get my video to look like film?

First you have to define what a ?film look? means to you personally, because the history of movies shot on film covers a wide range of looks. It may be easier to simply decide what look from video you don?t want and try and minimize that aspect.

Three important issues to consider:

Resolution. 35mm and Super-16 film have more resolution than standard definition video (NTSC & PAL), that is, they have a greater ability to record fine detail. Standard definition (SD) video cameras try and make up for this lack of resolution with artificial sharpening called ?edge enhancement?. However, this ?edgy? look (with black or white lines appearing around objects) is one of the uglier aspects of video photography and the reason why so many people say that video ?looks too sharp? and compensate by using lens diffusion filters. The problem is even worse for consumer DV cameras that need to compensate for their softer image quality by using heavy levels of edge enhancement.
Solutions: Use a camera & recording format with more resolution if possible. HD is high enough in resolution to be in the range of Super-16 and doesn?t absolutely require edge-enhancement. If shooting in SD, reduce the level of edge enhancement to a barely perceptible level, but not so low that the image looks out-of-focus. After this is done, then diffusion filters may also be used (if still needed) to soften the harsh edginess.

Motion rendition. A film camera capturing reality 24 times per second in whole frames, with the shutter usually closed 50% of the time, produces very unique motion artifacts compared to a standard interlaced-scan video camera. For example, an NTSC camera captures reality 60 times per second (actually 59.94) and often with no shutter employed, and each capture only constitutes one of two fields, which are interlaced into a frame for presentation on a CRT screen. Motion sampled at 60 times per second is much smoother, and when combined with no shutter being employed, the video image seems more hyper-real and ?live? than the classic staccato, strobiness of 24 fps film.
Solution: Shoot in true progressive-scan, ideally 24P / 25P. 30P will also lend more of a filmic quality to motion, but 30 does not convert well into 24 (for transfer to film) or 25/50 (for conversion to PAL video.)

Exposure latitude. Color negative film can capture a wider range of scene luminence. Video in particular has trouble handling bright areas of overexposure, which tend to burn out quickly without detail (?clipping?.)
Solution: Control excessive overexposure through lighting, filtering, and exposing. Polas can help reduce glare and ND grads can help darken bright areas along one side of the frame.


9. What is the difference between Mini DV, DVCAM, and DVCPRO?

The short answer is that they are not different standards; all use the DV25 codec (25 Mb/sec, 5:1DCT compression) and all are 1/4? tape formats. The difference is the tape speed / track width. DVCAM runs 1.5X faster than Mini DV, and DVCPRO runs 2X faster than Mini-DV. The faster speeds / greater track width adds to the robustness of the recording, with fewer drop-outs.

More information:

In July 1993, Matsushita, Philips, Sony and Thomson announced they would share a common platform for developing a digital standard for home video. More than 50 companies then joined in this historical consortium. Formally called DVC before becoming DV (Digital Video), this universal format was built around two key parameters : a 5:1 DCT intraframe compression (similar to M-JPEG) and a new family of compact cassettes using 1/4? tape. It was introduced in 1996.

DV offers an image quality comparable to analog Beta-SP, with fewer generational problems -- although many DV camcorders are consumer designs while all Beta-SP camcorders are for the professional market, so you still may get superior image quality with Beta-SP because of the quality of the cameras.

DV records separately the Luma and the Chroma components giving a line resolution of about 500 lines while Hi8 provides 400 lines.

The audio allows either two 48 kHz/16 bits channels or four 32 kHz/12 bits channels with non linear quantification.

NTSC DV uses 4:1:1 color subsampling; PAL is 4:2:0. This is fine for home video, but has limitations for broadcast post-production, especially for chromakey work.

DV cassettes come in two sizes : Standard/ Full Size (L), which is 125mm by 78mm by 14.6mm; and Mini DV (S), which is 66mm by 48mm by 12.2mm. The new DV VCRs will accept both, but the current home camcorders accept only the Mini DV.

Sony created the ?prosumer? DVCAM format; DVCPRO (also called DVCPRO25) was developed by Panasonic for a line of professional camcorders.

One can record DVCAM on a DV tape, even though the I.C. memory chip (which can be used to quickly sample stills from edit points, plus record other data) is only 4k bits in DV versus 16k for DVCAM. Considering a given tape, the recording length is shorter in DVCAM than in DV, since the speed is higher.

Though DV and DVCAM have no longitudinal tracks, DVCPRO uses two of them, one for the control tracking the other for audio cueing. This track can be used as a third audio track, but its bandwidth is limited to 6 kHz, due to the longitudinal speed. The control tracking is based upon a traditional LTC, to shorten pre-roll delays, better than pilot frequencies used in DVCAM tracks. Concerning the coating, Panasonic prefers metal particle (MP) for DVCPRO over metal evaporated (ME) because of its strength.

10. What is DVCPRO50?

Another Panasonic tape format like DVCPRO(25), but with better 4:2:2 color subsampling and a higher data rate of 50 Mb/sec. The compression rate becomes 3.3:1 instead of 5:1; the tape speed is doubled as well and becomes 67.6 mm/s, though the tracks are still 18 microns width, but every image is recorded on 24 tracks instead of 12.

Links :
<a href="http://en.wikipedia.org/wiki/Dv" target="_blank"><a href="http://en.wikipedia.org/wiki/Dv" target="_blank"><a href="http://en.wikipedia.org/wiki/Dv" target="_blank">http://en.wikipedia.org/wiki/Dv</a></a></a>
<a href="http://www.high-techproductions.com/dvFAQ.htm" target="_blank"><a href="http://www.high-techproductions.com/dvFAQ.htm" target="_blank"><a href="http://www.high-techproductions.com/dvFAQ.htm" target="_blank">http://www.high-techproductions.com/dvFAQ.htm</a></a></a>
<a href="http://www.adamwilt.com/DV.html" target="_blank"><a href="http://www.adamwilt.com/DV.html" target="_blank"><a href="http://www.adamwilt.com/DV.html" target="_blank">http://www.adamwilt.com/DV.html</a></a></a>


10. What is the connection between focal length and depth of field? Does a 50mm lens on a 16mm camera have the same depth of field as it does on a 35mm camera?
11. What is 3-perf / 2-perf?
12. What does anamorphic mean?

13. As a DP, how do I get an agent? Do I need an agent?


Agents are good for negotiating rates and getting your name out there to producers, sending out your reel, sending you scripts, etc. In terms of finding jobs, they can help but often your contacts are still the primary way of finding new projects. It?s hard to just go out and find an agent as a beginner. Generally when it?s time in your career to need one, they will be calling you instead of the other way around. The other moment is when you have a big job offer and need help in negotiating a deal; that?s when agents get interested in you. It may take a few years of professional work as a DP before you get an agent.

14. Should I rent or own equipment?

It makes sense to own equipment when: (a) you need a camera as a learning tool and to make personal projects on your spare time; (cool.gif when you are working regularly and can accurately calculate how long it will take for the equipment you buy to pay for itself; © when you are doing a long-term project shooting irregularly. It makes more sense to rent when you are doing a single project within a limited period of time. Generally you can afford to rent better equipment than you can afford to buy. Plus owners have to deal with insurance, maintenance, and building up a decent collection of accessories.

15. What is the ASC?

The American Society of Cinematographers. Not a film industry union for camera crew people but an honorary society for cinematographers, membership by invitation only. Founded in 1919, its declared purpose is: ?to advance the art of cinematography through artistry and technological progress, to exchange ideas and to cement a closer relationship among cinematographers.?

16. What is the name of the union in Hollywood and how do I join?

The union is IATSE (International Alliance of Theatrical Stage Employees, Moving Picture Technicians, Artists & Allied Crafts). Camera crews fall under Local 600, which is nationwide although divided roughly into three regions. Basic membership requirement is proving to Contract Services (an outside agency) that you have worked 100 days, over a three-year period ending at the date of application, in the job classification that you wish to join under (DP, Operator, 1st AC, etc.) The work must have been paid work, meaning you will have to provide proof of that (letter from payroll company, paycheck stubs, etc.) and it must have occurred in the U.S. or its territories. There are a few other circumstances that lead to membership so talk to Contract Service if you want to know more. Local 600 members are allowed to work on non-union projects, although they should notify the union as to what they are working on. Generally people join the union when they reach the point where they are being offered union jobs.

17. Does DV have more or less resolution than Super-8?

In theory, slow-speed Super-8 color reversal probably has more resolution than consumer DV; this is most visible when projecting well-shot Super-8 reversal originals. In practice, it is hard to maintain this level of resolution when converting Super-8 to other formats, especially if the photography is grainy. Plus many consumer Super-8 cameras have mediocre lens optics and poor steadiness which can further reduce sharpness. One may be able to create more acceptable results with a DV camera for large-scale presentation due to the lack of grain in the image, even if there is not much difference in resolution compared to Super-8. But if the ?film look? is also important, Super-8 has that in spades, being film to begin with.

18. How do I blow-up 16mm/Super-16 to 35mm?

19. How do I blow-up Super-8 to 35mm?


These days, probably the best method would be to transfer Super-8 to 24P HD, and then record the HD image to a 35mm internegative for making prints.

20. What is a digital intermediate?

21. What are the best lenses made?


The ?best? lenses are the ones that create the look you want for the scene. They may be quite old, soft, and prone to flare if that?s what you require.

22. Should I go to film school? Which one?

You won?t get a definitive answer on this one. Someone who went to film school and then had a successful career in the film industry may have a more positive assessment than someone who went but was not successful, or didn?t go yet was successful anyway. And since most people only attend one film school in their lives, they are unlikely to have much insight into the programs at other schools.

No matter which one you choose, remember that the best teacher is yourself. You have to be motivated to teach yourself using whatever tools and resources the school provides, rather than expect some formal education so well-designed that it can turn any novice into a professional. Possibly the biggest advantage to film school is the ability to meet and work with fellow students; these connections may lead to work after graduation. This is one argument for picking a film school with a fairly high success rate for graduates entering the film industry.

23. What are the effects of different shutter angles?

A film camera shutter is an intermittent (stop & go) spinning disk with an opening that allows light to hit the film at some moments, but stop the light at other times to allow the film to advance to the next frame for exposure. Usually the disk is a half-circle, i.e. 180 degrees out of 360. This means that half the time, the shutter is closed and the other half, it is open and the film is being exposed. So shutter angle combined with frame rate affect shutter speed. Shutter speed affects exposure but also the amount of blur any movement will have in the frame.


25. How do I shoot a TV set or computer monitor?

26. What is Technicolor?


Technicolor is a motion picture laboratory. It was also the most successful color process for movies before the invention of color negative and print stocks in the late 1940?s. Technicolor had an earlier two-color process in the 1920?s; a three-color process was invented in the 1930?s.

It involved shooting with a 3-strip Technicolor camera, inside which, behind the lens, was a prism to split the light in two directions. One direction went through a green filter to record the green information onto orthochromatic b&w negative. The other direction went through a magenta (blue-red) filter to record the blue information onto blue-sensitive b&w negative. That piece of film was dyed red, so that after exposing the film, the light passed through it, was filtered red, and recorded the red information onto panchromatic b&w negative.

The three b&w negatives were printed onto three positive b&w ?matrices? which had the ability to hold color dye in proportion to the density of the image. The red record matrix was dyed cyan; the blue record dyed yellow; and the green record was dyed magenta. These rolls were then run in contact, one at a time, with a blank roll containing a mordant to absorb dyes. The process was similar to how three-color images are printed on paper for books & magazines. The Technicolor printing process was called ?dye transfer? or ?imbibation? (?I.B.? for short). After the release of Kodak Eastmancolor negative in 1950, Technicolor obsoleted the bulky 3-strip cameras by 1955, but continued the dye transfer printing process well into the 1970?s. It was revived briefly in the late 1990?s using a prototype printer but was not financially successful. Technicolor dismantled the printer and has no plans on rebuilding it.

Technicolor dye transfer prints were known for their rich colors, deep blacks, fine grain, and great archival dye stability. Probably the closest current print stock to that look is Kodak Vision Premier 2393.

27. How do I get a 2.39 image when shooting in 16mm/Super-16?

If the goal is a 35mm 2.39 : 1 ?scope? print, your choices are basically: (1) cropping Super-16 top & bottom from its native 1.68 : 1 to 2.39 : 1? or (2) using standard 2X anamorphic lenses built mainly for 35mm cameras on a regular 16mm camera. With a 2X compression in the photography, the unsqueezed image would be about 2.66 : 1 (if the original 16mm frame is 1.33 : 1) so would have to be cropped on the left and right sides to 2.39 : 1. If you shot with a Super-16 camera, the 1.68 negative would yield a 3.36 : 1 image when unsqueezed. You probably need to find a 16mm camera with a PL-mount since that?s what most anamorphic lenses have except for Panavision?s.

Ultimately, simply cropping Super-16 spherical photography to 2.39 might be the better method unless you wanted the particular optical artifacts that come with using anamorphic lenses.

28. What is the difference between Super-35 and anamorphic?

29. What is the difference between hard and soft lighting?


There are many misconceptions and misunderstandings about soft vs. hard light.

Vittorio Storaro describes light as either a point source (which he calls ?puntiform?) or a broad source (?multiform?). A point source is a very small, sharp light that creates a strong separation between light and shadow with almost no penumbra (the transition from light to dark.) The shadows created by a point source are very crisp and sharp-edged. At the other end of the spectrum, a broad source creates a very gradual transition from light to dark and the shadows created are very soft-edged if sometimes non-existent. And in between hard and soft light, point source and broad source, are infinite variations from barely softened to super-diffused, shadowless light.

A soft light can be translated into "wrap-aroundness". This implies that the source in itself isn't that important -- it's where you place it in relation to the object that you want to light. The more it wraps around the object, the softer it will be perceived.

The key rule here is that the softness of a light is determined by the RELATIVE size of the source to the OBJECT. In other words, from a photographic subject?s point of view, a 4?x4? soft source up close and a 20?x20? soft source farther away may appear to be the same relative size in their field of view. Therefore the softness of the shadow those two light sources create and the amount they wrap around the subject will be the same.

ANY source can be a soft source -- even the hardest spotlight ever created -- if the subject is so close to it that the size of the source becomes relatively larger. The same is true for a large source: it can become hard if far enough away to become very small relative to the subject. The prime example of this is the Sun, which is a huge object in space but so far away as to create relatively sharp shadow patterns.

Now to our real experiment: Get the "hardest" source you can find, like a 4K Xenon spotlight and light it up. Put on some sunglasses to protect your eyes and then hold up a golf ball just in front of the lens. Look at the light on the ball -- is it hard or soft?

Now move the same golf ball 30ft further down the beam and have a look at it -- is it hard or soft?

You will notice that the light was extremely soft in the first instance (although incredibly bright probably), but not in the last. This is simply because the SIZE of the source RELATIVE to the OBJECT in the first instance was very big -- i.e. the source was much bigger than the golf ball, therefore creating good "wrap-aroundness". Further down the line, the source hasn't changed size, but RELATIVE to the object it has done so significantly and has now become hard.

This is the Holy Grail right there: it really has got nothing to do with the source itself -- it's the size of the source compared to the object. Therefore a KinoFlo bank of fluorescent tubes, often referred to as a soft source, is ONLY a soft source if it?s lighting something SMALLER than itself. But it can just as well be used as a hard source if placed far away, OR if lighting a bigger object than itself. Therefore every source can be both hard or soft. But in practical terms, a KinoFlo is generally a soft source because it is often used in close proximity to the subject, not placed very far away as a key light.

The most common ways of creating a soft source is to either bounce a light off of a large surface or shine it through a large frame of diffusion material. But sometimes someone will shine a big lamp through a huge frame of silk, figuring that a very soft source will be created, and find the results not as soft as they had hoped for.

Why?

Simple? because if you LOOK at the silk, you will see a hot spot (usually star-shaped) in the middle where the big lamp shines through it. This means that the hot spot is the primary source, not the overall frame of silk, and since this is smaller relative to the object you?re lighting, a harder light results. You need to completely and evenly fill the frame of diffusion in order to take full advantage of its size.

One solution is to use a very heavy material that is an efficient diffuser of light (unfortunately silk is not that material). Stretched muslin, Full Grid Cloth (nylon), or heavy plastic diffusion material works well. But often even this is not enough to cause the lamp to spread out enough to fill the frame evenly. Sometime the solution is to first bounce the light off of a large white surface and THEN let that bounced light pass through the large frames of diffusion. Sometimes people will use multiple frames of diffusion in a row to keep softening the light. Sometimes using a less sharp lamp to begin with helps, like a multi-bank unit like a Dino or MaxiBrute.

Of course, there is no rule that you must maximize the softness of a light or that you can?t allow a hot spot to come through a diffusion frame. Some people will shine a light through a very weak diffuser like a frame of Opal gel, creating a barely softened light. Learn to appreciate all the textures in lighting, from very hard to very soft.

So to summarize, soft light is nothing but an exercise in creating a source that is bigger and more even than the object it?s lighting. Therefore putting a small piece of diffusion gel right on the barndoors of a light that?s several feet away will hardly create a soft lighting effect. In fact, in this case, the soft source created by the diffusion on the barndoors is BARELY larger than the lamp itself behind the diffusion, and thus the light created is barely softened no matter how dense the diffusing material is.


30. Can I shoot tests using movie film in a 35mm still camera? Can I use 35mm still camera film in a movie camera?
31. What are the steps for mastering film for a video release?
32. What are the cost differences between HD and film?

33. Why does b&w film have two E.I. values, one for daylight and one for tungsten?


Most b&w camera film is technically ?panchromatic? (sensitive to all color wavelengths) but the truth is that it is slightly more sensitive to the blue end of the spectrum than the red end, so the E.I. value is slightly lower (only by 1/3 of a stop usually) when shooting in tungsten light. Some lab b&w films are ?orthochromatic? with very poor red sensitivity. Early b&w films were only sensitive to blue light, so this was corrected (?ortho?) at some point to also record other color wavelengths except the redder ones, which wasn?t possible until panchromatic film was invented.

Plus:
FILM FORMATS EXPLAINED
VIDEO RECORDING FORMATS EXPLAINED
LIGHTING TERMS & EQUIPMENT EXPLAINED
COMMON FILM CAMERAS USED
COMMON VIDEO CAMERAS USED
SUGGESTED READING LIST

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