Support Understanding Image Quality

Understanding Image Quality

Image quality is influenced by a range of factors. Learn how scanning resolution, the physical condition of the original analogue media being digitised, and photograph scale can all impact image quality. 

What Resolution Should I Choose?

NCAP imagery is supplied at a range of resolutions depending on the collection and product purchased. Understanding the differences between available resolutions will help you choose the most appropriate product for your project. 

Why Do Images Differ?

Images scanned at exactly the same resolution may display very different levels of detail. This is because factors such as flying height, photographic scale and source material often have a greater influence on image quality than the scanning resolution.

Understanding Historic Photography

Many of our collections span decades of technological change. The resources below explain how image quality varies between collections and what level of detail can realistically be expected.

Learn More About:

A roll of black and white aerial film unspools from a blue reel. The reel has a black winding handle. The film passes over the bright white light of a flatbed scanner.

Choosing the Right Resolution and Format

Understand how image resolution and file formats affect image delivery, file size and usability. This guide explains the options available and helps you choose the most suitable product for your project needs.

2 purple-gloved hands prise apart a stack of slightly curled photographic prints.

Image Quality Factors

Explore the factors that influence image quality, from the condition of the original photograph to scanning methods and image processing. Learn why some images contain more visible detail than others.

A colour aerial photo of islands surrounded by a deep blue sea. There is one big island left of centre and a small one to the right. The islands have green grass and a mix of rocky and sandy shores. The sea is light blue over the sand.

Scale and Flying Height

Discover how aircraft flying height and photograph scale influence the level of detail visible within an image. Understanding these relationships will help you assess what information can realistically be identified and interpreted.

A black and white aerial photomap of a town surrounded by an irregular grid of black and white fields. The photomap is annotated with place names – including Stargard, the name of the town – and is overlaid with numbered map grid squares.

Second World War Imagery

Second World War aerial photography remains one of NCAP's most heavily used collections. Explore its unique characteristics, limitations and strengths to better understand image quality and set realistic expectations for available detail.

Two hands wearing grey gloves hold a slim cardboard box. They appear to be moving the box, and the bundle of boxes piled beneath it, on to the white shelving behind.

Understanding Collection Coverage

Learn why aerial photography coverage varies between locations, periods and collections, and how this can influence the imagery available for your project.

A purple gloved hand reaches in from the left. They are using a brush with a white handle to brush the surface of a black and white photographic print towards the nozzle of a black vacuum cleaner. There are other images and boxes on the table.

Pre-Digitisation Preservation

Learn how NCAP prepares historic films and prints for digitisation, helping to protect original materials while producing the highest-quality digital images possible.

2 smiling men in blue lab coats look down at a screen in the bottom right of the image. The man on the left has white skin, a light red beard and dyed red hair. The man on the right has white skin, is wearing a blue shirt and has short grey hair.

FAQs

Find answers to some of the most common questions asked of the NCAP team.

IN THIS SECTION

A colour aerial photo with a park containing trees and red paths at the left, and Buckingham Palace in the bottom left corner. The River Thames is to the right with the London Eye lying flat over it. The shadow of Big Ben is to the right of centre.

Case Studies

Explore the many new ways historical aerial imagery is being used today.

A colourful map of Bochum in Germany, with blue representing water, brown representing built-up areas and green representing countryside. 2 straggling lines of numbered black boxes indicate where a reconnaissance plane took photos.

How-To Guides

Use the step by step guides to help you navigate some of the key tools from the NCAP archive.

A person with dark hair and glasses in a blue lab coat holds a black and white map in their gloved hands. The map is labelled ‘Sierra Leone’. In the background there are desks which have blue and black film rollers and image scanners on them.

Understanding Technical Terms

A glossary of some common technical terms associated with aerial photography.

2 smiling men in blue lab coats look down at a screen in the bottom right of the image. The man on the left has white skin, a light red beard and dyed red hair. The man on the right has white skin, is wearing a blue shirt and has short grey hair.

FAQs

Find answers to some of the most common questions asked of the NCAP team.

2 men examine documents they are holding. The man on the left has light red hair and wears a blue shirt. The man on the right has dark brown hair and wears a grey jumper. 2 large colourised historic photos cover the walls behind them.

Contact Us

Find the best ways to get in touch with the team at NCAP for research support, project partnerships or image sales.

A close-up image of a piece of cream-coloured paper held by black gloved hands. It is torn on the centre fold lines and has creased and bent edges. It is printed with a form in black ink that has been completed in blue and grey handwritten text.

Subscriptions

Subscriptions allow you to zoom images on the website and access finding aids to help identify images.

2 purple-gloved hands prise apart a stack of slightly curled photographic prints.

Newsletter

Sign up to our newsletter to start receiving regular email news updates about NCAP.

A figure in a black jumper leans into the frame from the far right. They lean on a tabletop and are holding a computer mouse. On the desk there is a screen with a colour aerial photograph displayed on it. There is also a black, cylindrical canister which has white labels on it, and a document lying on the table.

Online Sources of Aerial Photography

As well as NCAP, here are some other places you can go for aerial photos and information.