Film orientation

Film orientation refers to the orientation in which a film element is wound onto a reel, the fashion in which a film element was manufactured, and the regions of a film element that can be used as waypoints during inspection and projection. Making heads or tails of film orientation can be a topsy-turvy endeavor, but is crucial to ensuring proper winds, investigation of past or newly incurred damages, and accurately citing locations throughout a film element.

This involves using a film element's frames, markings, and even the innate characteristics of film elements as points of reference. Common points of reference are reel labels, lab leader, title cards, and the soundtrack. While most rules and descriptions of film orientation are universal to every gauge and format, each does have its own caveats and characteristics, which will be noted throughout this article whenever applicable.

Head and Tail

Every strip of film has two ends: the head and the tail. In short, the head is the beginning of the element, and the tail is the end of the element.

While film elements can be inspected starting from either head-to-tail or tail-to-head, projection prints are intended to be projected from head to tail, which means winding prints onto reels as such is crucial. Identifying the head and tail is also useful for describing general locations throughout a reel (e.g., "the film snapped in the projector about 200ft from the head").

Head

The head refers to the intended beginning of a film element. For projection prints, the head is often comprised of various elements such as head leader, head lab leader, and countdown, all of which lead up to the first image or start of reel.

There are a number of ways to orient yourself towards the head. Projection prints often come with the head labeled as "HEAD" (or, simply the letter "H" followed by the reel number) either on a sticker, a piece of tape, or even on the leader itself. Often times, there are multiple instances of the word "HEAD" or "START" throughout the head leader and head lab leader, so keep an eye out for such markings. If there isn't any head leader, or if you are mid-reel and unsure of where the head is, look at any frame right side up and the top of that frame will be oriented towards the head. Credits or title cards are often best for this purpose since they are rarely intentionally printed upside down, unlike shots of people or close-up details, although they too can be used as reference if the shot's correct orientation can be confirmed.

If a print is wound onto a reel (or a core) with the head on the outermost layer, the reel is referred to as "heads out". Reels are most often wound heads out when it is prepared and ready for projection.

Tail

The tail refers to the intended end of a film element. For projection prints, the tail is often comprised of various elements such as blank leader (usually black, sometimes clear), tail lab leader, and tail leader, all of which immediately follow the last image or end of reel.

While projection prints often come with the tail leader labeled just like the head leader (mostly in the form of tape fastening the reels for shipping), these labels are often less detailed, and at times entirely lacking. However, much like the head, there are usually markings indicating "TAIL" or "END" found throughout the tail lab leader. Obviously, the tail shouldn't have any countdown, although you can never be too sure, as scrap countdown is sometimes used as makeshift tail leader. If there isn't any tail leader, or if you are mid-reel and unsure of where the tail is, look at any frame right side up and the bottom of that frame will be oriented towards the tail. Credits or title cards are often best for this purpose since they are rarely intentionally printed upside down, unlike shots of people or close-up details, although they too can be used as reference if the shot's correct orientation can be confirmed.

If a print is wound onto a reel (or a core) with the tail on the outermost layer, the reel is referred to as "tails out". Reels are most often wound tails out when being prepared for shipping or long-term storage.

Base and Emulsion

Every strip of film has two distinct sides: the base and the emulsion. In short, the base is the translucent foundation upon which the emulsion, a layer of image-forming gelatin coating, is cast. As a basic analogy, if we think of a strip of film as a painting, the base is the canvas and the emulsion is the paint.

While identifying the base and emulsion side is useful on its own for citing the location of damages and other artifacts, it is equally useful for identifying the type of wind in which the film was printed (see Print winds) as well as deducing the inboard and outboard side.

Base side

The base side refers to the film base, which serves as the support and/or carrier for photosensitive emulsion. As mentioned above, think of the base as the canvas to a painting's paint (which would be the emulsion).

The base is most commonly identified by its shiny, glossy, and smooth appearance, which can be revealed by refracting light against its surface, ideally over a dark and non-reflective material like black cloth. If the reflection of the light source is sharp and clear with little change, almost like a mirror (especially compared to the opposite side), then you are most likely looking at the base side.

If a print is wound onto a reel (or core) with the base side facing away from the reel's center on the outermost lap, the reel is referred to as "base out" and/or "emulsion in". Reels are most often base out when being prepared for shipping or long-term storage so as to protect the emulsion side as much as possible.

Emulsion side

The emulsion side refers to the side upon which layers of emulsion are coated onto the film base. Basically, this is the side where the image itself rests. As mentioned above, think of the emulsion side as the paint on a painting's canvas (which would be the base).

The emulsion side is most commonly identified by its matte, dull, and embossed appearance, which can be revealed by refracting light against its surface, ideally over a dark and non-reflective surface material like black cloth. If the reflection of the light source looks faint or milky (especially compared to the opposite side) and you are able to see what looks like three-dimensional imprints (a.k.a., embossing), then you are most likely looking at the emulsion side. Embossing can most easily be seen on frames of high contrast images such as ones with text or stark lighting.

If a print is wound onto a reel (or core) with the emulsion side facing away from the reel's center on the outermost lap, the reel is referred to as "emulsion out" and/or "base in". Reels are most often emulsion out when they are ready for projection, since most prints are meant to be projected so that the emulsion side faces the lamphouse.

Be warned that the emulsion side on newer polyester stocks can often look almost as shiny as the base side due to protective improvements to the chemistry during manufacturing. Once in a blue moon, you will encounter prints that have undergone some kind of alternative "protective" treatment that essentially laminates the entire length of a reel, which makes the previously mentioned method of identifying the emulsion side virtually impossible since both sides become equally glossy. While this really complicates things for 16mm prints (where the print could be A- or B-Wind), there is another method that can be used for 35mm prints that takes advantage of the soundtrack area as a frame of reference. If you look at a print in such a way where the head is facing up and the soundtrack area is on the left, the side that is facing you will (almost) always be the emulsion side.

It's also worth noting the existence of duplitized positives, which, in short, are prints that have an emulsion layer on both sides of the film. These are most common for prints using early subtractive color systems such as Gasparcolor (c.1932-1944). However, most of these early experimental color prints were made in an era when cellulose nitrate was still the reigning film base, so you will rarely interact with such prints unless at a theater with a nitrate certified booth.

Print winds

There are two types of print winds: A-Wind and B-Wind. They refer to the only two ways a print's base and emulsion side can be oriented during the manufacturing process. This is crucial to ensuring proper film orientation for projection. While nearly every single 35mm projection print will be A-Wind, 16mm prints can often be B-Wind.

A-Wind

If you look at a frame in the way it is meant to appear on screen (right side up, outboard edge on the left) and the emulsion side is facing you, the print is A-Wind. This is best done with frames featuring text, since you can then simply tell yourself, "If you can read it correctly through the A-mulsion, the print is A-Wind." Most 35mm projection prints will be A-Wind, although A-wind 16mm prints are not uncommon.

This is because original camera stock is always considered B-Wind, and since negative raw stock is most common for 35mm productions (and many 16mm productions), this means any positive prints struck from the original camera negative (or any duplicate negative material) will be the opposite orientation of the camera original, thus making it A-Wind.

Example(s): Original Camera Negative --> Duplicate Positive

or,

Original Camera Negative --> Fine Grain Master (Positive) --> Intermediate Negative --> Release Print (Positive)

B-Wind

If you look at a frame in the way it is meant to appear on screen (right side up, outboard edge on the left) and the base side is facing you, the print is B-Wind. This is best done with frames featuring text, since you can then simply tell yourself, "If you can read it correctly through the B-ase, the print is B-Wind." Most 16mm projection prints will be B-wind, and very rarely will you find 35mm B-wind prints.

This is because reversal stocks are much more common for 16mm productions. Since original camera stock is always considered B-Wind, any prints struck from this reversal material must go through an extra intermediate stage, making its subsequent duplicate the same orientation as the camera original.

Example(s): Original Camera Positive --> Intermediate Negative --> Release Print (Positive)

Single-perf 16mm sound prints with a B-Wind should be properly identified in anticipation of focus adjustments to the soundhead on projectors that feature such an adjustment, such as Eastmans or Kodak Pageants.

Inboard and Outboard Edges

The inboard and outboard edges refer to both edges of a film element. These terms are useful as descriptors for locations across the width of a frame or fragment of film (e.g., "there are continuous vertical emulsion scratches visible towards the outboard edge"). They are defined by their relative location between the projector and the projectionist.

Inboard

The inboard edge refers to the edge of the film that is facing towards the inside of the projector when threaded for projection. For 35mm sound prints, this is the edge that is furthest away from the optical soundtrack area, as the soundtrack always faces outboard. For single-perf 16mm sound prints, this is the edge closest to the soundtrack, opposite to the side with perforations. For prints with no optical soundtrack, you can identify the inboard edge by looking at a frame with the head facing up and the emulsion side facing you -- the inboard edge will be on the right. Properly placed motor and changeover cues will always be placed towards the inboard edge.

Outboard

The outboard edge refers to the edge of the film that is facing towards the projectionist when threaded for projection. For 35mm sound prints, this is the edge that is closest to the optical soundtrack area, as the soundtrack always faces outboard. For single-perf 16mm sound prints, this is the edge closest to the perforations, as the perforations always face outboard. For prints with no optical soundtrack, you can identify the outboard edge by looking at a frame with head facing up and the emulsion side facing you -- the outboard edge will be on the left.

Winds and their usages

Winds can refer to a few different things: winding methods (S-Winds or C-Winds), print winds (A-Wind or B-Wind), or wind orientations (e.g., heads out, emulsion out).

Wind orientations

Wind orientations refer to the various ways a film element can be wound onto a reel or a core. They are most commonly defined by which end of the film and side of the film is facing out and away from the center of the reel. The terms can also be reversed and essentially mean the same thing (e.g., "heads out, base out" means the same thing as "heads out, emulsion in"), however, the most common terms for each wind will be used below.

You will often find instructions from the owners of the print included within its packaging specifying preferred wind orientations before shipping and returning the print. Different distributors, releasing houses, and archives each have their own preferences for wind orientations.

Heads out, emulsion out

This is the most common wind orientation for feed reels prepared for projection. For 35mm projection, a reel wound heads out, emulsion out should be coming off the left side of the reel. This ensures that the film will be projected in proper sequence and orientation, with frames positioned in the film gate upside down, the emulsion side facing the lamphouse, and the soundtrack (if any) facing outboard.

Tails out, emulsion in

This is the most common wind orientation for reels wound onto the take-up during projection. This wind orientation is also considered archival best practice for reels prepared for long-term storage. This is because this wind orientation is the exact opposite of that which prepares the reel for projection (assuming that heads out, emulsion out is the de facto standard for feed reels), physically encouraging whoever removes the reel from storage to wind it to the correct orientation and thus properly inspect the print before projection.

Heads out, emulsion in

This is a less commonly used, although equally viable, wind orientation for feed reels prepared for projection. For 35mm projection, a reel wound heads out, emulsion in should be coming off the right side of the reel. This ensures that the film will be projected in proper sequence and orientation, with frames positioned in the film gate upside down, the emulsion side facing the lamphouse, and the soundtrack (if any) facing outboard.

Despite its lack of widespread usage in North America, this is technically the wind orientation officially recommended by SMPTE as of 1970 with the publication of SMPTE RP 39-1970. It's important to note that this recommended practice was issued at a time when cellulose acetate was the reigning film base for release prints, which has very different physical characteristics to polyester release prints, which is the standard today. Since the same experiments that led to RP 39-1970 have not yet been conducted on polyester release prints, the recommended practice is arguably outdated in terms of establishing a universal standard, although remains just as applicable to acetate release prints.

SMPTE RP 39-1970

SMPTE RP 39-1970 is a SMPTE Recommended Practice stating that 35mm release prints should maintain an emulsion in orientation throughout the duration of its theatrical run, both in the instant of projection and in storage/shipping. This is based on a 1965 paper published in a SMPTE Journal issued the same year that studied the effects certain wind orientations on acetate film prints have on projection performance. In short, their findings show that theatrical prints kept in an emulsion-in orientation (to and from feed and take-up reels during inspection and projection) resulted in "superior image quality" in the instant of projection with a noticeable lack of flutter, in-and-out focus, and gradual focus drift.

This is due to the innate properties of acetate film base, which is prone to "plastic flow" (the tendency for the shape of plastics to "flow" and shift as force is applied against it over time) and "core set" (when the resting shape of a film's base molds itself to its wound orientation when stored on a core or reel). This means that, instead of reversing wind orientations in the instant of projection (causing unpredictable strain to the print undergoing plastic flow and core set), keeping a film's orientation as unchanged as possible in storage and during projection results in greater mechanical stability for the print, and since almost all take-up mechanisms are designed for clockwise (thus, emulsion-in) take-up, it follows that feed reels should be wound emulsion in just as well. It's also worth noting that the study showed how the adverse effects of even one wind in the opposite orientation can take weeks to reverse themselves for acetate prints.

While the findings in this study are well-researched and quite conclusive, there are a few things to consider when placing the study's findings within today's context.

Most importantly, the paper along with SMPTE RP 39-1970 itself was published when acetate was still the reigning film base for theatrical release prints. Polyester film base, which effectively phased out acetate base as the standard for print stock in the 1990s, is known to be much more resistant to core set with the action of plastic flow taking much, much more time to show its effects; the caveat being that, for this same reason, it is just as resistant to reversing the effects of core set once it's set in.

On top of this, RP 39-1970 merely makes the case for maintaining emulsion-in orientation primarily for limited theatrical runs, not necessarily long-term storage, implying an acknowledgement of the somewhat more forgiving nature of acetate core set and the reversibility of its adverse effects -- so, if one can confirm a print has been kept in storage for more than a few weeks wound emulsion in, the reported performance benefits should be noticeable in the booth and on-screen. However, considering how this standard never fully stuck, it's quite common for prints to be regularly wound every which way as it passes hands between archives, distributors, and exhibitors. Because of this, the reported benefits of emulsion-in feed reels are arguably impossible to guarantee without knowledge of its previous wind orientations, which are rarely if ever noted, let alone shared.

That all being said, this does not mean that adoption of the heads out, emulsion in standard is any less effective, especially if a print is subject to multiple screenings across a week or two, in which case some amount of mechanical stability could be gained over time. An argument can be made that, if you stay true to heads out, emulsion in as a standard, the best case scenario is that you project a print that has been stored emulsion in, in which case you reap the benefits of maintaining the wind; and the worst case scenario is that you project a print that has been stored emulsion out, in which case you get the same results as regularly projecting emulsion out.

Tails out, emulsion out

This wind orientation has very little usage as it leaves the emulsion side exposed during winding when it has no practical reason to. This wind orientation is most often found when initially receiving prints, depending on the print owner's preferred wind orientation.

Winding methods

There are effectively only two methods of winding from one reel to another: the S-Wind and the C-Wind. Any single use or combination of the two will result in one of the wind orientations described above.

There's a strangely unique logic to achieving certain wind orientations with certain winding methods that can be confusing to understand, so lots of practice and trial-and-error is recommended.

S-Wind

An S-Wind consists of winding film from one reel to another from bottom-to-top or top-to-bottom, thus making a an S-shape while winding. One S-Wind will reverse the orientation of the end and side of the film initially facing out, but not the direction in which the film is coming off the reel.

Example: Performing an S-Wind on a reel initially wound tails out, emulsion in coming off the reel counter-clockwise will result in a reel wound heads out, emulsion out coming off the reel counter-clockwise.

While it is not usually recommended (to avoid any unnecessary torsion on more delicate prints), an S-Wind performed with a 180-degree twist in the film from one reel to another will only reverse the end of the film initially facing out, preserving the side of the film initially facing out and the direction in which the film is coming off the reel.

Example: Performing an S-Wind with a twist on a reel initially wound tails out, emulsion in and coming off the reel counter-clockwise will result in a reel wound heads out, emulsion in and coming off the reel counter-clockwise.

However, doing this reverses the inboard and outboard edges relative to proper projection orientation, meaning the whole reel must be flipped around, effectively reversing the direction in which the film comes off the reel. For all practical purposes in projection, doing this reaches the same result as simply performing one C-Wind.

C-Wind (or, Straight Wind)

A C-Wind consists of winding film from one reel to another from bottom-to-bottom or top-to-top, thus making a C-shape while winding. The C-Wind is also referred to as a Straight Wind as the film travels from one reel to the next in a straight line. One C-Wind will reverse the end of the film initially facing out as well as the direction in which the film is coming off the reel, but will preserve the side of the film initially facing out.

Example: Performing a C-Wind on a reel initially wound tails out, emulsion in coming off the reel counter-clockwise will result in a reel wound heads out, emulsion in coming off the reel clockwise.

While it is not usually recommended (to avoid any unnecessary torsion on more delicate prints), a C-Wind performed with a 180-degree twist in the film from one reel to another will reverse all three factors of a wind orientation: the end and side of the film initially facing out as well as the direction in which the film is coming off the reel.

Example: Performing a C-Wind with a twist on a reel initially wound tails out, emulsion in and coming off the reel counter-clockwise will result in a reel wound heads out, emulsion out and coming off the reel clockwise.

However, doing this reverses the inboard and outboard edges relative to proper projection orientation, meaning the whole reel must be flipped around, effectively, once again, reversing the direction in which the film comes off the reel. For all practical purposes in projection, doing this reaches the same result as simply performing one S-Wind.