Colour Wheel

Colour Wheel and Complimentary Colours

• "red and green
• blue and orange
• yellow and violet

The complement of each primary color (red, blue, or yellow) is roughly the color made by mixing the other two in a subtractive system:

• red complements (blue + yellow) = green
• blue complements (red + yellow) = orange
• yellow complements (red + blue) = violet

When two complements of opaque paint are mixed, they approximate black. For example, a little bit ofultramarine mixed with orange, produces a dark variation of black. Placed side by side as tiny dots, in partitive color mixing, they produce gray. As colored light projected on a white screen, in additive color mixing, they produce white.

The use of complementary colors is an important aspect of aesthetically pleasing art and graphic design. This also extends to other fields such as contrasting colors in logos and retail display. When placed next to each other, complements make each other appear brighter. On an artistic color wheel, complementary colors are placed opposite one another. "

- description source wikipedia

Film Photography Basic Information

Film Speed

Each type of film has an ASA or speed, e.g. 100, 200, 400, 1600, 3200 etc

The higher the film speed, the lower light the film becomes. i.e.; very bright conditions – 100 ASA Low light – 3200ASA.

However the grain increases as film speed increases.

35mm is the everyday film format for compact and SLR and is also in disposable cameras.

120 is medium format.120 produces larger image sizes form 6 x 4.5 cms, 6 x 6 cms, 6 x 7 cms, 6 x 8 cms, 6 x 9 cms, depending on the brand of camera.

Colour Negative Film

produces ‘negative’ images for printing large professional prints to minilab style prints.

General purpose neg film e.g. Fuji superia 100/200/400/800/1600.

This is known as C41 process.

Transparency Film

produces ‘slide’ type images. Can also be printed but produces poorer quality prints than neg film.

General purpose transparency film is Fuji Sensia 100/200/400

Professional transparency film e.g. Fuji Provia 100F/400F, Fuji Velvia, Kodak EPP.

This is known as E6 process.

Black & white film

e.g. Ilford  FP4, HP5 traditional film technology (50 -70 years old)

Ilford Delta 100/400/3200  new technology, finer grain and sharper than traditional.

Fuji Neopan 400/1600 very similar to Ilford FP4/HP5

‘Pushing’ film

It is possible to increase the film rating on the camera e.g. A 200 ASA film rated as a 400 has been pushed 1 stop. This is useful in lower light conditions with bright light film. Camera function would indicate a slower shutter speed to get enough light to produce a decent negative. Too slow would produce ‘camera shake’ casing a blurry negative. By pushing the film you allow shutter speed to increase so camera shake is not visible. 

However Pushed films can typically have higher contrast and with colour films have a colour bias. They also have a higher granularity.

Photographic paper

For photographic prints form negatives, for use only in a dark room.

Ilford multigrade paper is one of the best printing papers.  It has a full multigrade range. (00 – 5) This means from any negative you can produce a very soft feel (grade 00 – low contrast) to a very hard feel (5 – high contrast), by using multigrade filters.

These effects can be combined in a print to produce strong contrast whilst maintaining shadow detail, some expertise will be required to do this. Other brands have an effective multigrade range of 0 – 3, and therefore inferior.

RC - Resin coated paper

Is the most popular, this has the full multigrade range and is much quicker to dry, whilst maintaining it’s flatness. This is in contrast to FB - fibre-based.

Resin coated comes in three surfaces; gloss/pearl/satin.

Size varies, but for a contact sheet a page of film is laid on multigrade paper and is exposed to even light through an enlarger, 9.5” x 12” is normal. RC papers are the only ones that can go through processing machines.

FB – fibre based paper

Is for the experienced printer. This paper cannot be processed in open trays. It dries unevenly and can curl up, may need to go through a machine to flatten it. It does however produce a beautiful print with a nice ‘heaviness’. There is more silver in these papers, hence producing a richer image. This paper is available in matt or gloss. N.B. This paper cannot be put through processing machines.

See Kodaks website and Ilfords website for further more technical information.

Paper Glossary

Quantities 1 quire = 25 sheets 1 ream = 500 sheets (480 sheets for acid free tissue) 1 millpack = The size of the pack as shipped from the mill (usually 100 sheets, but will vary according to the paper). Paper Sizes Paper Size (millimetres) 4A0 2378 x 1682 2A0 1682 x 1189 A0 1189 x 841 A1 841 x 594 A2 594 x 420 A3 420 x 297 A4 297 x 210 A5 210 x 148 A6 148 x 105 A7 105 x 74 A8 74 x 52 A9 52 x 37 A10 37 x 26 Antiquarian 1350 x 730 Atlas 864 x 660 Cartridge 661 x 534 Colombier 876 x 597 Crown 510 x 380 Demy 570 x 440 Double Crown 760 x 510 Double Demy 900 x 570 Double Elephant 1020 x 690 Double Foolscap 680 x 430 Double Medium 920 x 580 Eagle 1067 x 730 Emperor 1829 x 1219 Extra Large Atlas 889 x 689 Foolscap 430 x 340 Hand 559 x 406 Imperial 760 x 560 Large Post 530 x 420 Large Post Double 840 x 530 Medium 580 x 480 Pott 394 x 317 Quad Crown 1020 x 760 Quad Foolscap 680 x 680 Quad Medium 1160 x 920 Royal 675 x 510 Royal Hand 635 x 508 Super Royal 710 x 510 Paper Weight Metric (GSM) Imperial (LB's) 150- 160 72 180 - 200 90 240 - 250 120 285 - 300 140 410 - 425 200    Paper Surfaces Rough Natural surface of paper when dry. Not (or cold pressed) Between Hot Pressed and Rough (pressed between cold rollers) Hot Pressed (HP) Smooth finish sometimes pressed between hot rollers.    Glossary "A" series ISO range of paper sizes reducing from A0 (841 x 1189mm) by folding in half to preserve the same proportions at each reduction. acid free Free from any acid content of other substances likely to have a detrimental effect on the paper or its longevity. antique A general term applied to a surface which imitates the laid character of an old sheet. Today the term is often used to denote a rough finish. archival paper A term loosely used to indicate paper with long lasting qualities, is acid free, lignin free, usually with good colour retention. B series ISO range of paper sizes, falling between the A and C series, designed for items such as wall charts and posters. bast fibre The inner bark of such plants as flax, hemp, gampi, mitsumata and kozo, separated from the outer bark and suitable for papermaking. beater A machine which alters or modifies the properties of fibres. beating Hand or mechanical maceration of fibres to modify their characteristics and prepare them to become pulp. board A general term for thick, stiff paper over a certain weight; on average 250-300 gsm. bonding strength The ability of fibres on the surface of a paper to adhere to one another and to others below the surface. brightness Paper's ability to reflect white light. Brightness values are a measure of the reflectivity of paper to light under controlled conditions, on a scale of 0 - 100; most white papers have brightness values of 75-90. brittleness The tendency of paper to crack or break when bent or embossed. BSI  British Standards Institution.  Standards co-ordinating body (cf. ANSI). buffering agent (also called 'alkaline reserve') An alkaline substance, usually calcium carbonate or magnesium carbonate, occurring naturally in a water supply or purposely added by the papermaker to help counteract acidity in paper. bulk The volume or thickness of a paper in relation to its weight. C series ISO range of sizes for envelopes. calcium carbonate (Chalk) A pigment, which can be used as a filler, a white coating substance and a buffering agent. calendering The process of pressing paper through rollers (usually of hardened, polished metal) to increase its surface smoothness. caliper The thickness of a single sheet of paper measured with a micrometer in 1/1000 in., millimetres or microns. cellulose The basic substance of papermaking: the main part of the cell wall of the plant. Cellulose fibres are not pure enough (except for cotton) to be used directly for papermaking. chain lines, chain wires Heavier, more widely spaced lines (or wires) which run at right angles to lines on the surface of a laid mould. chemical pulp Wood reduced to pulp by a variety of chemical processes all of which involve the cooking of the fibrous raw material with chemicals in order to extract the cellulose fibre. china clay A filler or loading agent. coated paper Paper coated with china clay or other filler to give a smooth surface making it suitable for the printing of fine detail. cockling Wavy edges (or wrinkling or buckling) caused by unequal expansion due to paper being damper or drier than the atmosphere. cold pressed (CP) Same as NOT. contraries Unwanted pieces of material which have become embedded in a sheet, e.g. dust, hairs, string, buttons, etc. cotton The purest form of cellulose produced in nature, requiring the least amount of processing before it can be used for papermaking. cross direction Paper cut at right angles to the direction of the paper machine. Paper is weaker and expands more across the cross direction than along the machine direction. curing The maturing of paper for an amount of time, before packing and selling. curling tendency A curl caused by unequal shrinkage which develops either when the moisture content of the paper is changed by atmospheric conditions or when the paper comes into contact with moisture. deckle The removable wooden frame that fits over the mould to contain the pulp. deckle edge The wavy, feathered or ragged edge on the sides of a sheet of handmade paper caused where the pulp seeps under the deckle frame during formation. deflocculant A substance which disperses fibres and prevents them from entangling in the pulp. endpaper Strong paper used for securing the body of a book to its case. felt A rectangular sheet of absorbent woven material, usually of wool, cut larger than the paper, onto which newly formed sheets are couched. felt finish A finish to the top surface of paper created by the texture of the felt; often with a special weave. felt mark A mark in the paper caused by the impression of a defect in the felt, such as a worn patch. felt side The top surface of the pulp, as distinct from the wire side. Fourdrinier The standard type of machine on which paper is made at high speed in a continuous web. Sheets produced in this way are called 'machinemade'. gelatine A type of sizing obtained form animal tissues, which is applied to the surface of paper to make it impervious to water and to aid resistance to bleeding during printing. Can affect colour. grain, grain direction The alignment of fibres in a sheet of paper caused by the flow of the web of wet paper in a cylinder-mould or Fourdrinier machine. gsm or g/m2 The weight of paper and board when expressed in metric terms as grammes per square metre. Hot Pressed (H.P.) One of the three traditional surface finishes of handmade paper. Today this term denotes the smoothest surface, achieved by passing sheets between heavy metal rollers (occasionally heated). hygroscopic Said of the nature of a material which tends to make up the moisture content of the atmosphere. Imperial 1. A large sized sheet, 762mm x 559mm. 2. The traditional system of weights and measures set up in Britain in 1836, in which the basis weight of a sheet of paper is expressed in pounds (lbs.). India paper Very thin, high-quality opaque rag paper often used for printing Bibles. ISO sizes Range of paper and envelope sizes established by the International Standards Organisation, including notably the A, B and C series. linting The process by which clumps of fibres are released from the paper surface during printing due to the tackiness of the ink, especially in lithography. moisture content Amount of moisture in paper, expressed as a percentage of weight. mordant A substance used to fix a dye to a fibre. NOT, not Short for 'Not Hot Pressed'.  One of the three traditional surface finishes of handmade paper (between Rough and Hot Pressed), produced by passing between felts. Called Cold Pressed (C.P.) in the U.S. paper mulberry (mulberry tree) This is a broad term for a number of trees from whose inner bark paper is made; Broussonetia papyrifera is probably the most widely used; in Thailand it is called saa, in Japan kozo. pH The pH value describes the acidity or alkalinity of a paper; it is a measure of the availability of free hydrogen ions. 0pH is very acid; 14pH is very alkaline; 7pH is neutral. quire A twentieth part of a ream; today a quantity of 25 sheets of paper. rag Indicates that a paper has been produced from cotton linters. The term 'rag content' describes the amount of cotton fibres relative to the total amount of material used in the pulp. rattle The sound produced by shaking a piece of paper, indicating the hardness of the sheet. ream An old word for a quantity of paper. Today taken to refer to 500 sheets of good paper. relative humidity (RH) The amount of water vapour present in the atmosphere expressed as a percentage of saturation, measured with a hygrometer. rosin A commonly used internal sizing agent; occasionally also used for surface sizing. It is acidic in nature, and is detrimental to the permanence of paper. Rough One of the three traditional surface finishes of handmade paper; a rough surface is properly obtained by loft drying in natural air. shives Specks of impurities in the raw fibre discernable in the finished sheet. sizing A solution, or process of applying such a solution, intended to make paper moisture-resistant to varying degrees. Size can be added at two stages of the paper-making process. 1. In internal sizing (also called beater- or engine-sizing), size is added to the beater. 2. In surface sizing (also called external- or tub-sizing), dried papers are passed through a solution of gelatine (or glue, casein or starch) traditionally contained in a bath or a tub; surface size can also be applied by brushing or rubbing. smalt Deep blue pieces of glass pulverized and used as a colouring agent. smoothness Essentially the surface flatness of a paper. It is not the same as 'gloss' (which is an optical property) and is not related to porosity. spur A group of sheets dried naturally together. substance The weight or grammage of a sheet of paper expressed in gsm or lbs per ream. surface finish The surface character of a sheet of paper, described in terms of its texture, e.g. Rough, NOT, H.P., burnished , hammered. texture The surface detail or finish of a paper, which can be a natural result of the quality of the pulp, processing or drying, or a contrived impression. tooth Describes a surface texture that grips a drawing pigment. traditional A term used to refer to accepted, established and valued techniques customary to papermaking processes of the past. vellum 1. The prepared inner side of calfskin or kid skin. 2. A paper surface which imitates true vellum, notably any matt wove type; often used to describe mouldmade and Japanese papers. waterleaf Used to describe a paper that contains no sizing and is therefore generally very absorbent. watermark A translucent design in a sheet of paper that can be viewed as a paler area when held up to the light. Typically watermarks are linear, formed in wire. web A continuous length of paper (I.e. a roll or reel) as distinct from a sheet. wet strength The strength of a finished sheet of paper when it is saturated with water. wire side The underside of paper in contact with the mesh during making, as distinct from the felt side.

Oil Paint Technique

OIL PAINTING TECHNIQUE

There are many different ways to paint but the two most commonly used ones are, Traditional  (indirect painting), a slow and controlled method. Wet-on-wet (direct painting) with this method, the painting is usually completed in one sitting, often referred to alla prima - at the first.

The traditional method often uses tonal under-painting as the basis of the picture, usually grey (grisaille) or brown (bistre) in colour. The tonal values of the finished under-painting should be lighter in tone than required in the finished work, because the application of the glazes will lower the value. Often more complex in application, whereby transparent and opaque layers of paint are applied in succession, opaque layers can also be applied as a scumble. The transparent layers are usually applied as a glaze of thin colour over the more opaque layers, the opaque layer being allowed to dry before the glaze is applied. The final layer of paint can be painted directly into the last glaze. Colours applied by this method usually bring a greater luminosity to the finished work than can be achieved in the direct method. Acrylic gesso can be used successfully for under-painting, especially if you wish to make a quick start.

With the wet-on-wet method, the painting is completed with, in effect, one layer of paint, which is usually opaque or semi-opaque. There is a need to make definite decisions about the work, before and as it progresses. All the elements of the painting have to be mentally handled at the same time, with regard to tone, composition, shape, form and colour, etc.  Doing a sketch or drawing before starting the work can be very helpful.

When working in the traditional way it is important to work 'Fat over Lean'.  'Fat' is paint straight from the tube or with linseed oil added, this makes the paint more flexible when dry. 'Lean' is paint with no added oil or thinned with solvent. The way it works is to start with paint that has low oil content (lean), followed by paint with high oil content, then paint with added linseed oil (fat). As a general rule of thumb, working from dark colours to light colours helps to maintain this principal.

Whites

Vary considerably, and have different uses,

Painting whites are not usually suitable for priming or under painting.

Cremnitz slow drying.

Flake white lacks opacity.

Titanium whitest and most opaque slow drier.

Zinc least opaque cold white for tints and glazes.

The Fat over Lean Principle

First layer of paint thinned with solvent.

Next layers of paint have less solvent.

Next layers are tube paint - no solvent.

Next layers are tube paint with a little linseed oil.

Final layer is tube paint with more linseed oil.

Mixing the Paint

You can mix paint on the palette, on the brush, with a knife or on the canvas, each will give a different effect - try them all. The flat, round bladed 'palette knife', is the best for mixing paint on the palette. Mix small amounts of paint at first until you feel better able to judge quantities.

Dark colours will overpower light colours very quickly. It's very easy to 'over mix' colours on the palette, this can lead to very flat, dead looking paint. Something to be avoided!

When mixing colour on the brush, try not to use it like a palette knife, instead pick small amounts of the colour up with the brush, either by tapping the brush into the colour or pulling it through the paint.
It's easy to use a painting knife like a palette knife, but painting knives are engineered to give the correct edge for applying paint to the canvas. You can load one colour at a time or several on the blade edge. There are a variety of shapes and sizes of painting knives, recognised by their cranked handle.

Georgian Oil Colour

By Daler Rowney These oil colours offer artists high performance colours at an economical and uniform price across all 57 colours in the range. Georgian Oil Colours are produced to the same exacting standards as Artists' Oil Colour. Georgian Oil Colours are carefully blended and tested to produce the most brilliant colour, and match tint, and texture from batch to batch. All 57 colours have fine working qualities and a high degree of permanence.

Computer - Memory Size Summary table

IEC Standard
bit	bit	0 or 1
byte	B	8 bits
kibibit	Kibit	1024 bits
kilobit	kbit	1000 bits
kibibyte (binary)	KiB	1024 bytes
kilobyte (decimal)	kB	1000 bytes
megabit	Mbit	1000 kilobits
mebibyte (binary)	MiB	1024 kibibytes
megabyte (decimal)	MB	1000 kilobytes
gigabit	Gbit	1000 megabits
gibibyte (binary)	GiB	1024 mebibytes
gigabyte (decimal)	GB	1000 megabytes
terabit	Tbit	1000 gigabits
tebibyte (binary)	TiB	1024 gibibytes
terabyte (decimal)	TB	1000 gigabytes
petabit	Pbit	1000 terabits
pebibyte (binary)	PiB	1024 tebibytes
petabyte (decimal)	PB	1000 terabytes
exabit	Ebit	1000 petabits
exbibyte (binary)	EiB	1024 pebibytes
exabyte (decimal)	EB	1000 petabytes

Computer Information - kb, KB, Mb, GB

Abbreviations like Kb, KB, Mb and GB

Are often confused, misunderstood or used incorrectly. Here's a brief explanation of proper usage.

Let's start at the beginning. The only data that a computer can understand is on and off. But those two simple commands can be grouped into millions of combinations and it is the way they are grouped in series that creates complex data.

The basic unit is called a bit (binary digit). Each bit has an electronic switch, or gate. If the gate is open the bit is on and electricity can go through. The computer reads on or open switches as a number 1. If the gate is closed or off, the electricity is blocked and the computer reads off bits as 0.

Bits can be grouped together to allow more complex code. Eight bits are grouped together to form a byte. This allows 256 possible combinations of 1/0. The abbreviation for bit is a lowercase "b"; the abbreviation for byte is an uppercase "B". Bits and bytes can then be expressed in larger measurements. They are generally expressed in exponents of two, known as binary code.

The Standards

Although computer data is normally measured in binary code, the prefixes for the multiples are based on the metric system. The nearest binary number to 1,000 is 2^10 or 1,024; thus 1,024 bytes was named a Kilobyte. So, although a metric "kilo" equals 1,000 (e.g. one kilogram = 1,000 grams), a binary "Kilo" equals 1,024 (e.g. one Kilobyte = 1,024 bytes). Not surprisingly, this has led to a great deal of confusion.

In December 1998, the International Electrotechnical Commission (IEC) approved a new IEC International Standard. Instead of using the metric prefixes for multiples in binary code, the new IEC standard invented specific prefixes for binary multiples made up of only the first two letters of the metric prefixes and adding the first two letters of the word "binary". Thus, for instance, instead of Kilobyte (KB) or Gigabyte (GB), the new terms would be kibibyte (KiB) or gibibyte (GiB).

Adhesive Terms

Adhesive Terms

Term	Definition
Adhesion	The power of an adhesive layer to hold the parts of an assembly together.
Adhesive layer	The layer of adhesive between the parts to be stuck together.
Adhesive sealant	An adhesive that also acts as an elastic sealant.
Aerobic adhesive	Adhesive that sets on contact with the air.
Anaerobic adhesive	Adhesive that sets when air is excluded, by catalytic effect (of a metal).
Application	Coating the surfaces to be stuck together with the adhesive.
Base	The basic ingredient of an adhesive, on which its properties largely depend.
Binder	In multi-component reaction adhesives, components that form the basic part of the adhesive.
Bonding	The fixing of an adhesive (setting) by means of physical or chemical processes.
Bonding time	The period of time taken for the assembly to achieve sufficient firmness to bear the load exerted on it.
Catalyst	A substance that triggers a chemical reaction without itself being altered.
Cement	A paste-like sealant; depending on its composition, it may be either rigid or elastic once it has set, and may have adhesive properties in addition to its sealant properties.
Cohesion	The holding power within the layer of adhesive.
Cold adhesive	An adhesive that sets at room temperature (20°C).
Contact adhesion time	The period of time when using a contact adhesive during which the dry adhesive layers may still be bonded together (= open time).
Contact pressure	When using a contact adhesive, the pressure applied to the assembly to achieve a bond.
Creep	The effect of strain and/or time on the shape of polymer layers; even under little stress the adhesive layer changes shape. When stress is exerted, the adhesive layer gradually changes shape as a result of creep.
Dispersion	Solid particles suspended (not dissolved) in a liquid.
Evaporation time	When using a contact adhesive, the period of time necessary for the solvent to evaporate from the adhesive applied to both sides of the assembly, so that when the parts are placed together they bond immediately.
Final firmness	Maximum firmness after the adhesive has set; expressed in newtons per square centimetre (N/cm_). 10 N corresponds to 1 kg.
Fixing	Holding the parts to be assembled together (using clamps, collars, presses, etc) while the adhesive sets.
Flashpoint	The lowest temperature at which a substance (solvent) may evaporate and produce a flammable compound.

Glue	Originally an adhesive based on egg white. Now used indiscriminately to mean an adhesive, mainly in connection with woodworking. The word now includes adhesives on an animal, plant or synthetic base.
Hardener	Components that affect the hardening of multi-component reaction adhesives.
Indicator	A substance that indicates a chemical reaction by changing colour.
Initial bond	State of bonding achieved after a certain amount of time when the fixings holding the assembly together can be removed, although the final load cannot yet be exerted on the assembly.
Joint gap	The space between the parts to be assembled.
Joint thickness	The average distance between the parts to be stuck together (= thickness of the layer of adhesive).
Mixing ratio	The ratio in which the components of two- or multi-component adhesives and any fillers used must be mixed together in order to achieve the desired adhesive result.
Natural resin	Semi-liquid substance exuded by conifers, used as a basic ingredient in adhesives, paints and cements.
Open time	The period of time when using a contact adhesive during which the dry adhesive layers may still be bonded together.
Polymerisation	In polymerisation, small molecules (monomers) combine to create giant molecules (polymers), without changing their composition to any great extent.
Polymers	Macromolecules that affect cohesion; a basic ingredient of adhesives.
Resin	Base for adhesives.
Setting time	Period of time taken by a reaction adhesive to polymerise and form a completely set plastic layer. For single-component adhesives, the setting time starts when the adhesive is applied to the surfaces to be stuck together; for adhesives with two or more components, it starts when the components are mixed.
Shelf life	The period of time during which an adhesive stored according to the manufacturer's instructions (packaging, temperature, humidity) retains its expected properties.
Solvent	Volatile (i.e. evaporates readily) liquid added to adhesives to keep them in usable condition. Usually readily flammable. The adhesive bonds when the solvent evaporates.
Synthetic resin	A synthetic adhesive agent in adhesives and components of reaction adhesives (phenolic, epoxy and polyester resins).
Warm-setting	Setting at an (artificially) raised temperature.
Wet adhesion time	The period of time during which wet adhesion is possible
Working life	The period of time between the mixing and setting of two- or multi-component adhesives, i.e. the period of time during which the mixture can be worked. Most cold-setting adhesive systems have a short working life (minutes or hours), whereas most warm-setting systems have a long working life (hours or days)