Photographers' Formulary 1L Residual Hypo Test

Under the umbrella of top-notch photography essentials, Adorama presents the Formulary's Residual Hypo Test. This user-friendly chemical test is designed to ascertain whether a print or film strip has undergone sufficient washing. The test operates on the principle of creating a distinctive yellow stain of silver sulfide-silver thiosulfate on the white portion of a test print or the clear section of a negative filmstrip when the test solution is applied.

The Residual Hypo Test is a reliable tool for photographers, offering accurate results when the print or film has been treated with a Hypo Clearing agent and subsequently washed in water, or simply washed in water alone. However, it's important to note that the test may not provide accurate results if a Hypo Eliminator has been employed in the washing process. This is due to the presence of ammonia in the Hypo Eliminator, which interacts with the silver ions in the Residual Hypo Test Solution, thereby reducing their effective concentration.

In the realm of photography, the Formulary's Residual Hypo Test stands as an indispensable tool, ensuring the longevity and quality of your prints and film strips. It's an essential addition to your photography toolkit, helping you maintain the highest standards in your work.