Class: Senior Secondary School 1 (SS1 / SSS 1)
Term: 3rd Term
Week: 4
Age: 15 years
Duration: 45 minutes
Subject: Photography
Curriculum Theme: Trade
Previous Lesson: Film Development: Film Development Materials And Equipment Uses.
Topic: PRACTICAL EXPERIENCE OF FILM DEVELOPMENT PROCESS
Subject Matter: Development tank method, See-saw method

Specific Objectives

By the end of the lesson, pupils should be able to:

Cognitive Domain:

Define film development.
State the steps involved in the development tank method.
Explain the procedure for the see-saw method of film development.

Affective Domain:

Appreciate the precision required in film development.
Show interest in darkroom photography processes.

Psychomotor Domain:

Demonstrate the proper use of a development tank.
Practice the see-saw method for developing film.
Successfully develop a roll of black and white film.

Observe safety precautions when handling darkroom chemicals.
Work responsibly with darkroom equipment.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Senior Secondary Schools.
State Unified Scheme of Work for Senior Secondary Schools.
Okafor, J. C. (2018). Introductory Photography for Senior Secondary Schools. Abuja: Learnwell Publishers.

Instructional Materials

The teacher will teach this lesson with the aid of:

Exposed black and white film.
Development tank with reel.
Developing chemicals (developer, stop bath, fixer, wetting agent).
Measuring cylinders.
Thermometer.
Timer.
Water bath.
Darkroom facilities or a simulated environment.

Rationale for the Lesson

This lesson helps pupils understand the practical steps involved in transforming an exposed film into a negative. It enables them to gain hands-on experience in film development, which is a fundamental skill in traditional photography. This practical knowledge is important for creating usable images from film.

Prerequisite/Previous Knowledge

Pupils should have prior knowledge of different types of photographic film, the basic parts of a camera, and the concept of a latent image.

Lesson Content/Board Summary

PRACTICAL EXPERIENCE OF FILM DEVELOPMENT PROCESS

Film Development Process

Film development is the chemical process used to convert the latent image on an exposed photographic film into a visible negative. This process involves a series of chemical baths, each with a specific function.

The main stages of black and white film development are:

Developing: The developer converts the exposed silver halide crystals into metallic silver, forming the image.
Stop Bath: This acidic solution halts the action of the developer, preventing over-development.
Fixing: The fixer removes unexposed silver halide crystals from the film, making the image permanent and light-safe.
Washing: Thorough washing removes residual chemicals to prevent staining and degradation of the negative over time.
Wetting Agent: A final rinse in a wetting agent helps to prevent water spots and promotes even drying.

Development Tank Method

The development tank method is a common and convenient way to develop film in a darkroom or a light-tight environment. It uses a light-tight tank, allowing development to proceed in normal room light once the film is loaded into the tank in total darkness.

The general steps for the development tank method are:

In total darkness, load the exposed film onto the reel and place it into the development tank. Secure the tank lid.
Pre-wet the film with water for 1-2 minutes (optional, but recommended).
Pour in the developer solution at the correct temperature, start the timer, and agitate according to instructions (e.g., first 30 seconds continuously, then 10 seconds every minute).
Pour out the developer and immediately pour in the stop bath, agitating for 30 seconds.
Pour out the stop bath and immediately pour in the fixer, agitating for the recommended time (e.g., 5-10 minutes).
Pour out the fixer and wash the film thoroughly with running water for 5-10 minutes.
Apply a few drops of wetting agent to the tank, fill with water, and gently agitate for 30 seconds.
Remove the film from the reel and hang it to dry in a dust-free environment.

See-Saw Method

The see-saw method is an alternative film development technique, often used for sheet film or when a development tank is not available. It involves gently moving the film back and forth through a tray of chemicals.

The steps for the see-saw method are:

In total darkness, place the exposed film into a tray containing the developer solution.
Gently lift one end of the film and then the other, allowing it to “see-saw” through the solution to ensure even development. Continue for the recommended development time, maintaining agitation.
Transfer the film to a tray of stop bath, continuing the see-saw motion for 30 seconds.
Transfer the film to a tray of fixer, continuing the see-saw motion for the recommended fixing time.
Wash the film thoroughly in a tray of running water or by transferring it between several changes of water.
Optionally, soak the film in a wetting agent solution.
Hang the film to dry in a dust-free environment.

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction
Teacher’s Activity: The teacher greets the pupils and reviews the previous lesson on types of photographic film. The teacher then asks pupils what happens after film is exposed in a camera, leading to the concept of developing the film.
Pupils’ Activity: Pupils respond to questions and actively participate in the review.
Learning Point: Pupils recall previous knowledge and are prepared for the new topic.

Step 2: Explanation of Film Development Process

Time: 10 minutes
Teaching Skill: Explanation/Lecture
Teacher’s Activity: The teacher explains what film development is, its purpose, and the key chemical stages involved (developer, stop bath, fixer, wash, wetting agent). The teacher also highlights the importance of temperature and timing.
Pupils’ Activity: Pupils listen attentively, ask questions for clarification, and take notes.
Learning Point: Pupils understand the theory and stages of film development.

Step 3: Demonstration of Development Tank Method

Time: 10 minutes
Teaching Skill: Demonstration
Teacher’s Activity: The teacher demonstrates the step-by-step process of developing film using a development tank. This includes loading the film in simulated darkness, mixing chemicals, timing, agitation, and washing. The teacher emphasizes safety precautions.
Pupils’ Activity: Pupils observe the demonstration carefully, noting the sequence of actions and safety measures.
Learning Point: Pupils visually learn the practical steps of the development tank method.

Step 4: Pupils Practice Development Tank Method

Time: 10 minutes
Teaching Skill: Guided Practice
Teacher’s Activity: The teacher provides exposed film and development tanks to groups of pupils. The teacher supervises as pupils attempt to develop film using the development tank method, providing guidance and correcting errors.
Pupils’ Activity: Pupils work in groups to practice loading film and performing the development tank method under supervision.
Learning Point: Pupils gain hands-on experience and develop practical skills in using the development tank.

Step 5: Demonstration of See-Saw Method

Time: 5 minutes
Teaching Skill: Demonstration
Teacher’s Activity: The teacher briefly demonstrates the see-saw method, explaining its application and technique, especially for sheet film. This is done to show an alternative method.
Pupils’ Activity: Pupils observe the demonstration of the alternative development method.
Learning Point: Pupils are exposed to another technique for film development.

Step 6: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

Define film development.
State any three chemical solutions used in developing black and white film.
List three steps involved in the development tank method.
Explain briefly the main difference between the development tank method and the see-saw method.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 7: Conclusion

Time: 5 minutes
Teaching Skill: Summarization
Teacher’s Activity: The teacher summarizes the key learning points of the lesson, emphasizing the importance of accurate timing and chemical handling in film development. The teacher assigns homework: research common problems encountered during film development and their solutions.
Pupils’ Activity: Pupils listen to the summary and copy the homework assignment.
Learning Point: Pupils consolidate their understanding of the topic and prepare for further learning.

Lesson Keywords

Film Development – The chemical process of converting a latent image on exposed film into a visible negative.
Development Tank – A light-tight container used for developing roll film.
See-Saw Method – A technique for developing film, often sheet film, by gently rocking it through chemical solutions in a tray.
Developer – The chemical solution that converts exposed silver halide crystals into metallic silver.
Fixer – The chemical solution that removes unexposed silver halide from the film, making the image permanent.
Stop Bath – An acidic solution used to halt the action of the developer.

Differentiation

For pupils who grasp concepts quickly, the teacher can challenge them to identify and explain the chemical reactions occurring at each stage of development. For those who require more support, the teacher will provide one-on-one guidance during the practical sessions, using visual aids and simplified instructions, and ensuring they have ample time to practice each step.

Note for teachers using this lesson plan

Ensure all chemicals are prepared safely and at the correct temperatures before the lesson begins. Emphasize darkroom safety and proper handling of chemicals throughout the practical sessions. If a full darkroom is not available, simulate the light-tight environment for film loading and use amber safety lights for other stages if possible. Encourage pupils to document their observations and results.