My favourite film is Agfa Scala, a 200 ASA B&W professional slide film, designed for pictorial use.
It can be pulled to 100 ASA, or pushed as fast as 800 ASA. I have used the 35mm film at 200, 400 and 800 ASA, all with pleasing results. I used a roll which I rated at 800 ASA at the local "Carols in the Park" in 1995, and got a very nice picture of a young couple by candle-light, and various stage shots. The latest version, Scala 200x can be pushed to 1600 ASA.
The film is available in 35mm, 36 exp cassettes, 120 rolls, generally in 5 packs, and 4x5 inch sheets across Europe and North America, and in Australia (and New Zealand?). Prices in the US seem better than in the UK. Processing is not included. In the UK and US pre-paid envelopes can be purchased from retailers. In Australia availablity is generally limited to professional suppliers and some serious photo retailers. Most are willing to sell single rolls.
The Scala 200 page is only a click away! Click on the small slide images to see full screen versions. You can visit the Scala Gallery.
The "Availability" page lists formats and sizes of the different films, rather that outlets, but a list of Agfa offices can be found on the site.
The film must be processed using the Scala process, at a specialist lab. They are listed on AGFA's "Scala Laboratories" page.
Processing is now available from ICON Imaging Centre, also called Richard Wilson Imaging, in North Sydney, NSW, Australia! See above link for contact details. They also supply Scala film.
I have used Joe's Basement in London, UK and Color Lab Miami - CLM in Miami, Florida, USA for 135 format. Joe's Basement provide free pushing / pulling in half stop increments (just tick the relevant box), but do not mount the film (this is quite normal in Europe). It may be possible to pay extra for mounting. At CLM mounting is included in the price of the envolope, but there are no speed change boxes printed on it. Pushing is available for US$4.00 extra. It is possible to send them a note stating the required speed and quoting a Visa (or other) credit card number. I suggest you also note any speed changes on the outside of the envolope. More recently I had a 120 roll processed at ICON.
The AGFA Special B&W Films page, the original location of Scala information, lists some other interesting B&W films - useful if you're building your own photographic radar trap... :-)
Some beautiful photographs taken on Scala can be seen on Bill Hugglet's Joshua Tree National Park pages. (The last few are on Scala.)
One film not listed on the above pages, and only available in Europe is Agfa Dia Direct, a 12 ASA pictorial slide film, which includes processing (but not mounting). Despite the low speed it can be practical for general use by daylight or electronic flash. The extra few stops gained from a good prime (fixed focal length) lens compared to a typical 35-70 zoom can be helpful here. It is also useful for taking longer exposures of moving water to get a fluid motion effect. Exposures as long as to 1/4 or 1/2 seconds are possible at f16. (A polarizing or ND filter can also be used allow an even longer exposure time.)
Tip: I noticed that the UK Lab returned the processed film to Australia by airmail, while the German one used surface mail (as indicated in their conditions).
These films differ from a Kodak product which they describe as a monochrome slide film. The Kodak film is typically used to produce high contrast white on black title slides from black on white artwork, (which is a negative process).
Until about 1988, Agfa made a 32 ASA Dia Direct, which was processed in Australia at Nunawading (cool name!) in Melbourne.
Many years ago (1960s?) they made a "dual function" colour neg film without the usual brown mask called CT18 (or similar) which allowed easy printing on B&W paper (especially by amateurs), as well as colour prints. From the name I presume it was rated at DIN 18, (50 ASA). Many Kodak mini-labs in Australia now offer B&W prints from standard colour negs.
It is also possible to obtain pictorial B&W slides by:
The later is done by developing the film, bleaching out the image, fogging the remaining sensitive material with light or a fogging agent, then developing and fixing the resultant image. This in effect is using the film as its own negative. Ilford have published an brochure on reversal processing for their regular B&W films, and I have seem instructions for Kodak films in an old darkroom chemistry book from the US. Some of the chemicals may be hard to obtain.
Some labs won't E6 process XP2 because they fear it will affect their chemicals. Jadon in central Sydney did do a roll for me a few years ago.
Above I probably should have used the term EI instead of ASA when I was talking about the speed of pushed or pulled film. EI stands for Exposure Index and is functionally equivalent to ASA (American Standards Association) and the the first half of the ISO (International Standard Organisation). This is a linear system and is a measure of a film's sensitivity. Each step is a quarter "faster" than the previous. (Some speeds are more common that others.) A more sensitive film is said to be "faster", with the number a rating of speed.
The DIN (named for the German standars body) number also forms the second part of the ISO speed. It is a log system, where each quater increase is indicated an increase of one. An increase of 3 means twice as fast while an increase of 10 means 10 times the speed. (Communications technicians will see a likeness to the decibel system.)
A faster film allows you to shoot in lower light, to use a faster shutter setting, or to use a narrower apature (higher f-stop number) to gain a greater depth of field. A faster film uses larger grains of light sensitive material meaning that image quality is lower. Some long telephoto lens have a high f number, even at the broadest setting, while it is necessary to use a fast exposure to prevent the effect of vibrations bluring the image. At least in colour print films, current films are much better than those of 15+ years ago. Sometimes grain can add to the atmoshepre of a picture.
Sometimes, say when photographing running water you may wish the use a long exposure for a certain effect. Sometimes you will want a short depth of field to prevent a background in a close-up deing distracting. Sometimes you will want very rich colours under bright light, or fine grain for a large print. In these cases a "slower" film will be needed.
Sometimes you will wish to change the speed of a film around its normal speed. If you make it faster you are "pushing" and if slower, "pulling". Pushing is the most common of the two, and generally done with faster films.
In black and white negative film, the simplest film to process, speed depends on four factors - the time of development, the tempurature of development and the type of developer used, and with some, the strength it is mixed at. Typically extending the development time is the method of pushing, especially in the commercial environment where a large "bath" of chemical is held at a constant tempurature. A home user, or others that do in-house processing can select the best chemical, temperature and strength at will, in addition to time, following product instructions. In the more traditional black and white films the name is the predominant marking (Plus-X Pan and Tri-X Pan from Kodak, PAN-F, FP4 and HP5 from Ilford), with the speed shown being that obtained from a standard commercial process. The product information will show a significant number of processiong options.
Extended development time is used to increase the speed of E6 colour slide film (basically, all colour slide films except Kodachrome and Polaroid are E6) and is often done. Colour print can also have it's speed increased in this way, but it is perhaps less often done.
In the case of Agfa Scala, the process is a proprietry one, but similar methods to the above would be used.
It should be noted that most of the very fast black and white print and colour slide films are actually special 400 ASA films designed to be pushed to the higher speeds indicated on the box. In many the speed is prefixed with a "P" to indicate this. This is not the case with colour print films.
To get film pushed you generally have to deal with a professional lab. Ask whether they charge for pushing/pulling - some do not, some charge a flat rate while others charge per stop which gets expensive if you are going 3 stops from 400 to 3200. You waiting time may also increase, although many will be fairly fast anyway.
120 format film is a roll film which is about 6cm or 2¼" wide. It is used widely in profesional photography. The paper backed film travels from one roller to the other. The empty roller is then moved and becomes the take-up spool for the next roll. As the negatives or trasperancies are larger than 35mm or APS, the image quality is much higher. The length of film used varies between cameras - examples are 6x4.5, 6x6, 6x7 and 6x11 cms, each giving a different nomber of exposures per roll. My 6x6 cameras give me 12 exposures per roll. The position of the next frame is show by marks and numbers on the back of the film. The Box Browne which uses 620 film is a simpler / older form of these. Modern 120 cameras have a mechanically controlled film advance like a 35mm camera.