Focal length
Selection of view camera lenses is simple, because you will most likely find that two lenses, a wide angle and normal, will cover most of your field or studio camera needs.
Normal lenses
For a standard lens, a 150mm lens is the most versatile for 4x5 camera work. It gives a natural perspective, and is useful for any subject from landscape and portraiture to still life. It is also an excellent choice for close-up and macro photography in the field, because you can achieve life-size reproduction (1:1) without any accessories. The slightly longer 210mm focal length, common in 4x5 studio camera work, is also widely used with field cameras. In 8x10 format, the normal focal length is about double of 4x5, or 300mm to 360mm.
Wide angle lenses
The 90mm lens is the most popular and versatile 4x5 wide angle lens, useful for a wide range of subjects from capturing vast landscapes, and both architectural and table top subjects. In 8x10 format, the 200mm is equivalent to the 90mm in 4x5 for a basic wide angle.
Field Camera Considerations
When using focal lengths longer than 210mm with a 4x5 field camera, you may consider choosing a telephoto design lens (usually designated with a "T") rather than a regular design lens of the same focal length. For example, a 360mm "telephoto" lens may require only 260mm of bellows extension to focus at infinity, where a 360 "normal" lens will be require a full 360mm of bellows extension. Using only 260mm of extension for infinity focus will allow the use of additional extension for closer focusing. Telephoto lenses are ideally suited for field camera use because they require less bellows extension, are more compact, and lighter than equivalent focal length non-telephoto lenses.
Approximate equivalents of lens focal length
| 35mm | 4x5 | 8x10 |
| 20mm | 65mm | 120mm |
| 24mm | 75mm | 155mm |
| 28mm | 90mm | 200mm |
| 35mm | 115mm | 240mm |
| 45mm | 150mm | 300mm |
| 52mm | 180mm | 360mm |
| 63mm | 210mm | 420mm |
| 90mm | 300mm | 600mm |
| 105mm | 360mm | 720mm |
| 135mm | 480mm | 900mm |
Maximum aperture
Most large format camera lenses have maximum apertures of f/4.5 or f/5.6, which are excellent for viewing and focusing brightness. In some instances you will have a choice of the same focal length lens in two different maximum apertures. The f/4.5 lens will be brighter and easier to focus than a comparable lens with f/8.0 maximum aperture, but will be larger, heavier and more expensive. In actual picture taking, you will probably be using either lens at f/16 and image quality should be comparable.
Image Circle and Format Coverage
To get the greatest use of any view camera, camera movements are employed for adjustment of composition, or correction of converging vertical lines. When using camera movements, the image circle projected by the lens on to the film must be large enough to cover the film area without vignetting. The same concern holds true for coverage of larger film formats. For example, a 210mm lens designed for the 4x5 format may not project a large enough image circle to cover the 8x10 format. Conversely, a lens designed for the larger 8x10 format would easily cover the 4x5 format, and allow for generous camera movement in any direction.
When selecting a large format camera lens, check the lens manufacturer's specifications regarding image circle and recommended maximum format to see which lens best suits your needs. The image circle is usually expressed in a millimeter diameter, at infinity, and at a specific aperture of f/16 or f/22. Note these specifications when comparing lenses from different manufacturers, as standards may vary.
Usually, lenses that cover large image circles are larger, heavier and more expensive. For field landscape photography, a minimum of camera movement is typically required. For table-top photography, where extreme camera movement may be employed, a lens with wide image circle coverage is preferred to avoid vignetting.
