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Home / Photo Printing Equipment / Paisen BW-65 Hypo Solution for B&W Film Development: Washing Accelerator for Photo Paper, Configurable 5L Darkroom Supply

Attributes

Brand -
Category Office Equipment, Supplies & Services / Photo Printing Equipment
Origin -
Brand Paisen
Model Number BW-65
Volume 5 Liters
Chemical Type Hypo Clearing Agent / Washing Accelerator
Compatible Media Black & White Film and Photo Paper
Dilution Ratio 1:4 to 1:9 (Configurable)
Capacity per Liter Approx. 20-30 rolls of 35mm film
Shelf Life (Unopened) 24 Months
Storage Temperature 15°C to 25°C (59°F to 77°F)
Package Contents 1x 5L Concentrate Bottle, Usage Guide

6 reviews

A

Anonymous

Mar 30, 2026

Rating: 5/5

Perfect for high volume work

As a photography student, I go through chemicals quickly. This 5L bottle is economical and the dilution instructions are clear. It handles heavy loads of photo paper without losing effectiveness.

A

Anonymous

Mar 28, 2026

Rating: 5/5

Essential for quick turnaround

This washing accelerator significantly cuts down my processing time. The archival wash is thorough, and I love that the 5L size lasts me several months even with weekly developing sessions.

A

Anonymous

Mar 22, 2026

Rating: 5/5

Consistent results every time

I have been using Paisen products for years. The BW-65 ensures my negatives are completely free of fixer residue. My prints have never looked cleaner or lasted longer.

A

Anonymous

Mar 19, 2026

Rating: 4/5

Solid performer

Does the job well. Reduced my washing time from 30 minutes to about 10 minutes while maintaining archival quality. Smell is mild compared to other brands I've tried.

A

Anonymous

Mar 12, 2026

Rating: 4/5

Great value for darkrooms

Works exactly as described for both film and paper. The only reason for 4 stars instead of 5 is the cap design, which can be a bit tricky to pour without a funnel. Otherwise, excellent product.

A

Anonymous

Mar 03, 2026

Rating: 5/5

Highly recommended for B&W enthusiasts

If you are serious about black and white photography, this is a must-have. It prevents staining and ensures long-term stability of your images. Fast shipping too!

5 FAQ

Q: What is the recommended dilution ratio for photo paper?

A: For photo paper, we recommend a dilution ratio of 1:4 (one part concentrate to four parts water) for optimal clearing and washing acceleration.

Q: How many times can I reuse the working solution?

A: The working solution can typically be reused for 20-30 rolls of 35mm film or equivalent sheet film/paper area, depending on the load. Discard if you notice slowing clearing times or cloudiness.

Q: Does the 5L bottle come with a measuring cup?

A: The package includes the 5L concentrate bottle and a detailed usage guide, but a measuring cup is not included. Standard laboratory graduated cylinders work best for mixing.

Q: Is this product safe to pour down the drain?

A: While less toxic than older hypo solutions, please check your local environmental regulations regarding chemical disposal. We recommend neutralizing and disposing of it at a hazardous waste facility if possible.

Q: Can this solution be used for color film development?

A: No, the Paisen BW-65 is specifically formulated for Black & White film and photo paper. It is not suitable for C-41 or E-6 color processes.

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