Weak or grey blacks

Owned by print faults and poor maximum black as a defect entry; the printing remedy is owned by Part XVIII and Part XIX. Read it with poor maximum black, which is the same family diagnosed from the ceiling rather than from the floor.

What you see

A print with no true black anywhere and no clean white either. The whole thing sits in the middle. It looks flat, and — the characteristic complaint — it looks flat at every grade: going harder makes the light tones worse without giving the dark ones any more depth.

Held beside a print you were happy with, the difference is not that this one is lighter. It is that the range is shorter at both ends.

Likely causes

1. Fog on the paper base, from the safelight, from a room leak, or from the enlarger’s lamphouse.
2. Underexposure, which is the simplest cause and the one to eliminate first.
3. A developer that is exhausted, cold or too dilute.
4. Paper that has aged.
5. A grade too soft for the negative’s density range.

What is happening: the chemistry and physics

The distinction that matters is between a lowered ceiling and a raised floor, and they have different causes and different fixes.

A lowered ceiling — the paper genuinely cannot reach its published black — is poor maximum black: a development, fixing or material fault.

A raised floor is fog, and this is the commoner case. Fog is developed silver added everywhere, so the paper white is no longer white. The black may be perfectly normal in absolute terms; what has gone is the difference between white and black, and that difference is what the eye reads as depth.

That is why going harder does not help. A harder grade steepens the transfer between exposure and density, but it cannot subtract a constant that has been added to everything — and it prints the raised base harder too.

!The border settles it, and it takes one look

The easel blades masked the print’s border from the enlarger, so the border received no image exposure at all. On a correctly handled print it is paper white.

A grey border is fog, and nothing else. Nothing that came through the lens could have reached it.

A white border with grey blacks is a ceiling problem: the developer, the fixing, the paper or the exposure.

If the print was made without a border, one sheet with a coin on it under the safelight for a realistic working time will answer the same question.

And ILFORD describe this appearance as the signature of low-level safelight fogging, in words worth quoting because they name the fault rather than the measurement: safelighting can “appear safe, but be causing low level fogging. This may not be seen as safelight fog, but only as a general loss of photographic quality, particularly reduced contrast and lack of clear highlights.”

Diagnostic questions

• Is the border grey? Fog. Go to safelight fog and to Part XVI’s test.
• Does the severity track how long each sheet sat out? A dose accumulating with time is a safelight; a constant fault met by every sheet equally is the paper, the developer or a permanent leak.
• Is a fully exposed, fully developed sheet from the same box a proper black? That is the paper’s own ceiling, measured, and it separates the material from the process.
• What are the safelight’s bulb wattage, distance and filter age? The published condition is a 15 W bulb at not less than 1.2 m, with a filter cut-off no lower than 580 nm — and ILFORD ask that the filter be changed each year with the installation date recorded.
• Was the room checked with everything off, after fifteen minutes of dark adaptation? ILFORD’s own sequence is to find room leaks before testing the safelight filter.
• Was the enlarger’s lamphouse checked? It is a light source in the same room.
• What grade, against the negative’s range? ILFORD publish ISO range figures for their papers as a guide to matching the grade to the negative’s effective density range.

Corrective action

None on the print. Fog is developed silver in the paper.

Make it again once the room is corrected. Everything else about the negative and the printing is unaffected.

Prevention

Test the safelight and label the lamp with the paper, the distance, the bulb and the safe working time. Kodak’s definition of a safe time is any exposure less than or equal to half the time required to produce a detectable change, which turns a test result into a working number.

Change the safelight filter on a schedule and write the date on it. A faded dye passes shorter wavelengths than it did when new, and looks the same colour to you.

Test the room, not just the lamp, with everything off and your eyes given fifteen minutes to adapt.

Minimise the time paper spends out. Kodak’s reason is physical rather than procedural: the colour sensitivity of most emulsions does not end abruptly at a wavelength, so most papers retain some sensitivity to the very colours a recommended filter transmits. A safelight buys time, not immunity.

Keep paper in its bag inside its box, cool and dry, and use it within the maker’s two years.