The right battery for your Canon FTb is essential for capturing those classic shots. Finding the correct replacement battery ensures your camera is always ready, preventing missed moments and frustration. This guide will walk you through identifying and powering your Canon FTb simply and effectively, making sure your vintage gear keeps clicking.
Ever hauled out your beloved Canon FTb, ready to capture a perfect scene, only to find it dead? It’s a classic photographer’s lament! The Canon FTb, a legendary film camera, relies on specific batteries to power its light meter and other essential functions. Without the right juice, your beautiful machine is just a paperweight. But don’t worry! Keeping your FTb powered up is simpler than you might think. We’ll cut through the confusion and get you back to shooting in no time.
Many photographers face this challenge, especially with older cameras. Finding replacements for vintage batteries can feel like solving a puzzle. But the good news is, with a little knowledge, you can easily find compatible and reliable power sources for your Canon FTb. This guide is your straightforward roadmap to ensuring your camera is always ready for action!
Understanding Your Canon FTb’s Power Needs
The Canon FTb, a workhorse camera from the 1970s, uses a specific type of battery to operate its built-in light meter. This meter is crucial for getting accurate exposures, especially in varying lighting conditions. Unlike modern digital cameras that have complex electronic systems, the FTb’s needs are relatively straightforward, focusing on providing a consistent voltage for its metering circuit.
Historically, the Canon FTb was designed to use mercury batteries. For decades, the most common choice was the 1.35-volt RM400 (also known as PX625 or Mallory RM-625). These batteries provided a stable voltage perfect for the camera’s meter. However, mercury batteries pose significant environmental and health risks, and they are no longer manufactured or sold in most parts of the world. This is where the main challenge arises for FTb owners today.
Why Mercury Batteries Were Used (and Why They’re Different)
Mercury batteries were popular in older cameras because they offered a very consistent voltage output throughout their life. This meant the camera’s light meter would remain accurate until the battery was almost completely drained. This predictability was highly valued by photographers relying on precise metering.
The problem is that mercury is a toxic heavy metal. Environmental regulations have led to the phasing out of mercury-containing batteries. While effective, their hazardous nature makes them unsuitable for continued production and use. This global shift means FTb owners must find modern alternatives that can replicate the performance without the environmental impact.
The Impact of Voltage Differences on Meters
The original RM400 mercury battery operates at a steady 1.35 volts. Many modern replacement batteries, particularly alkaline equivalents, operate at a higher voltage, typically around 1.55 volts. This small but significant difference can lead to underexposed or overexposed photos if the meter isn’t adjusted or if the camera isn’t compensated for.
For example, if a 1.55-volt battery is used in a circuit designed for 1.35 volts, the meter will likely read the light as brighter than it is. This will cause the camera to set a faster shutter speed or a narrower aperture, resulting in a darker image (underexposure). Understanding this is key to choosing the right battery and ensuring accurate exposures.
Finding the Right Battery for Your Canon FTb
The good news is that with a bit of detective work, you can find excellent modern battery solutions for your Canon FTb. The key is to understand what type of battery you need and to look for options that either match the correct voltage or provide a workaround for any voltage discrepancies.
The Classic: PX625 and Its Modern Equivalents
The PX625 is the battery size historically used in the Canon FTb. When mercury batteries were phased out, manufacturers and photographers looked for alternatives. Here’s what you’ll typically find:
- SR44/LR44 (Silver Oxide/Alkaline): These are common button-cell batteries. While the LR44 is alkaline and has the higher 1.55V, the SR44 is silver oxide and also typically 1.55V but offers a more stable discharge curve, similar to mercury but still not identical. Some photographers use a pair of SR44s with a voltage regulator, or they simply adjust their exposure based on the slightly higher voltage.
- Zinc-Air Batteries (e.g., Rayovac 1.35V): These are specifically designed to replace mercury batteries. They operate at the correct 1.35-volt output. The challenge with zinc-air batteries is their lifespan. They are activated by removing a tab and exposing them to air, which starts a chemical reaction. Once activated, they have a shelf life of a few months to a year, depending on usage and storage. They are excellent for accurate metering but require more frequent replacement than alkaline or silver oxide cells.
- Voltage Regulator Adapters: Some companies offer small adapters that fit into the battery compartment and regulate the 1.55V from a common battery (like an LR44) down to the required 1.35V for your camera. This is a clever solution that allows you to use widely available batteries with the correct voltage.
Recommended Battery Types and Brands
When searching for the best battery for your Canon FTb, consider these reliable options:
- For Accuracy (and careful management): Zinc-air batteries designed for 1.35V applications are often the most straightforward for exact metering. Brands like Rayovac (e.g., Rayovac 312 or 675, often re-badged for camera use) are good choices. Remember that these are activated by air, so buy them when you’re ready to use them.
- For Convenience and Availability: Silver oxide SR44 batteries are a popular choice. While they are 1.55V, many photographers find that the difference is manageable, or they learn to compensate by adjusting their exposure settings. Brands like Energizer, Sony, and maxell offer reliable SR44 batteries.
- For a “Set and Forget” Solution: If you prefer not to worry about voltage or battery activation, investigate voltage regulator adapters. These can often be found from specialty photography accessory suppliers online. They allow you to use readily available batteries like the Energizer LR44 or Maxell LR44.
Where to Buy Your Canon FTb Battery
You can find batteries for your Canon FTb at several types of retailers:
- Online Retailers: Websites like Amazon, eBay, and specialized camera stores are excellent sources for all types of replacement batteries and adapters. You’ll often find the widest selection here.
- Camera Stores: Some physical camera shops still carry batteries for older film cameras. This can be a good option if you want to see the product in person and get advice from staff.
- Electronics Stores: Larger electronics retailers might carry common button-cell batteries like LR44 or SR44, though zinc-air options might be harder to find.
- Specialty Battery Shops: Some stores focus solely on batteries and might have niche options for vintage cameras.
Replacing the Battery: A Step-by-Step Guide
Changing the battery in your Canon FTb is a simple process, but it’s important to do it carefully to avoid damaging the camera or losing your battery. Always refer to your camera’s manual if you have it, but these general steps will guide you.
Step 1: Locate the Battery Compartment
The battery compartment on the Canon FTb is typically located on the bottom of the camera body. It’s usually a small, round compartment with a twist-off cap. Look for a small dial or a slot for a coin or flathead screwdriver to open it.
Step 2: Open the Battery Compartment
Using a coin or a flathead screwdriver, gently turn the cap counter-clockwise. Do not force it; if it’s stuck, try a little gentle pressure or jiggling. Be careful not to scratch the markings on the cap or the camera body.
Important Safety Note: Always ensure your camera is set to a neutral position (shutter speed set to ‘B’ or the slowest mechanical speed if possible, and the film advance lever not engaged) before changing the battery. This minimizes the chance of any internal electronic systems being active and potentially getting a surge.
Step 3: Remove the Old Battery
Once the cap is off, you’ll see the old battery. You can usually nudge it out gently with a non-metallic tool, such as a pencil eraser or a plastic spudger. Avoid using sharp metal objects like tweezers, as they could short-circuit the battery or scratch the battery contacts inside the camera.
Pro Tip: Make a note of which way the battery is facing (which side is up/down) before you remove it. This will help you insert the new one correctly.
Step 4: Insert the New Battery
Place the new battery into the compartment, ensuring it’s oriented correctly according to the markings (+) and (-) inside the compartment and on the battery itself. If you’re using a zinc-air battery, make sure you’ve removed the protective tab and allowed it to “breathe” for a minute or two before inserting.
If you’re using an adapter or multiple batteries (like two SR44s), follow the specific instructions for your chosen solution. Most adapters will have clear diagrams.
Step 5: Close the Battery Compartment
Gently screw the cap back on clockwise until it is snug. Again, don’t overtighten. The compartment should close smoothly.
Step 6: Test Your Camera
Turn on your Canon FTb and check if the light meter responds. Point the camera at different light sources and see if the needle or LED indicators move. You can also use an external light meter, an incident meter app on your phone, or even a sunny/16 rule test to evaluate the accuracy of your camera’s meter after the battery replacement.
For more detailed information on operating the Canon FTb and its metering system, consult resources like the Canon FTb Manual (PDF) which offers detailed insights into its functions.
Using Your Canon FTb with New Batteries: Tips for Accuracy
Once you’ve powered up your Canon FTb with a new battery, you might notice slight differences in how the meter behaves compared to the original mercury batteries. Here’s how to get the most accurate results:
Exposure Compensation and Metering
As mentioned, many modern batteries are 1.55V, while the FTb’s meter expects 1.35V. This can lead to a consistent error: a tendency to underexpose. Here’s how to handle it:
- Learn Your Camera’s Tendency: Shoot a test roll of film with your chosen battery. Take photos in various lighting conditions and bracket your exposures slightly (take one shot at the meter’s recommendation, one slightly brighter, and one slightly darker). Develop the film and see which exposures were closest.
- Adjust Settings Manually: If you consistently find your meter is underexposing by, say, half a stop, you can simply set your shutter speed or aperture one increment slower or wider, respectively. For example, if the meter says f/8 at 1/125s, you might choose f/5.6 at 1/125s, or f/8 at 1/60s.
- Use Available Light Meters: For absolute certainty, especially when starting out, use a reliable handheld light meter or a smartphone app that provides accurate incident or reflected light readings. Compare its readings to your FTb’s meter and make manual adjustments.
Battery Life and Storage
The lifespan of your new battery will depend on the type and how much you use your camera’s meter. Here are some tips:
- Zinc-Air Batteries: These have a shorter working life once activated (a year or less, even with minimal use). Store them in a cool, dry place before activation. Only remove the tab when you’re ready to install them in the camera.
- Silver Oxide/Alkaline Batteries: These have a longer shelf life and will last much longer in the camera, often several years, depending on usage. However, if you don’t shoot often, consider removing the battery to prevent drain or leakage.
- Turn Off the Meter: Many vintage cameras don’t have an automatic shut-off for their meters. To conserve battery life, get into the habit of removing the battery when the camera is stored for extended periods, or ensure the lens cap is on and the camera isn’t being pointed at any light source that might activate the meter.
Common Battery Issues and Troubleshooting
Even with the correct battery, you might encounter issues. Here are a few common problems and their solutions:
- Meter Not Working: Double-check that the battery is inserted correctly and is fully charged. Clean the battery contacts in the camera and on the battery itself with a pencil eraser or a clean, lint-free cloth. Ensure the battery compartment cap is screwed on tightly, as this often completes the circuit.
- Inaccurate Meter Readings: This can be due to the voltage difference mentioned earlier, a faulty meter in the camera, or a weak battery. If a fresh, correctly installed battery doesn’t resolve it, the camera’s meter might need professional calibration.
- Battery Leakage: If you find any white or crystalline residue in the battery compartment, it’s a sign of leakage. Carefully clean it out with a cotton swab dipped in white vinegar or lemon juice (to neutralize alkaline leakage), then wipe with a dry cloth. Ensure the battery compartment is completely dry before inserting a new battery. Always use reputable battery brands to minimize this risk.
Maintaining Your Canon FTb for Longevity
Keeping your Canon FTb in good working order involves more than just swapping batteries. Proper maintenance ensures your camera continues to capture stunning images for years to come.
Cleaning Your Camera
Regular cleaning is vital. Use a soft-bristled brush to remove dust from the camera body, lens mount, and viewfinder. For the lens, use a lens cleaning kit with a microfiber cloth and lens cleaning solution. Never spray cleaner directly onto the lens or camera body.
The sensor (in digital cameras) or the film plane (in film cameras) is extremely sensitive. For film cameras like the FTb, ensure the film chamber is dust-free before loading film. A gentle puff of air from a rocket blower can be very effective.
Storage Recommendations
When you’re not using your Canon FTb, store it properly. Keep it in a camera bag or a padded case to protect it from bumps and dust. Avoid extreme temperatures (hot or cold) and high humidity, which can damage internal components and fog the lens.
If storing for a long period, consider removing the battery to prevent potential leakage. You might also want to store it with a desiccant pack to absorb any moisture, especially in humid climates.
When to Seek Professional Service
While we often aim for DIY solutions, some issues require expert attention. If you experience any of the following, it’s best to seek out a reputable camera repair service:
- Complex Mechanical Faults: If the shutter speeds are consistently inaccurate across all settings, or if the film advance mechanism jams, it may need internal adjustment.
- Light Leaks: Persistent light leaks that aren’t a result of user error (like a improperly closed back) might indicate issues with the light seals around the film door or mirror.
- Accuracy of Light Meter: If you’ve tried multiple types of fresh batteries and the meter remains wildly inaccurate or completely unresponsive, the internal metering circuitry might be faulty.
- Major Physical Damage: If your camera has suffered a significant drop or impact, it’s wise to have it inspected by a professional.
Finding a good repair technician for vintage cameras can be challenging but is well worth the effort for preserving a classic piece of equipment. Resources like the Camera Revival website or dedicated forums can often point you towards trusted repair services.
Frequently Asked Questions (FAQ) about Canon FTb Batteries
What is the original battery for the Canon FTb?
The original battery for the Canon FTb was a mercury battery, typically the 1.35-volt RM400 (also known as PX625 or Mallory RM-625).
Are mercury batteries still available?
No, mercury batteries are no longer manufactured or sold in most countries due to environmental and health concerns. You will need to use a modern alternative.
What can I use instead of a mercury battery in my Canon FTb?
You can use zinc-air 1.35V batteries (like Rayovac 312), silver oxide SR44 (1.55V) batteries, or a voltage regulator adapter that allows you to use common button cells like LR44 (1.55V).
