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The exposure log

EX-1 and EX-2 are one card. Print them on the two sides of one sheet of paper and you have one exposure per sheet: everything on EX-1 is written before the shutter opens, and everything on EX-2 after the negative is dry. That division is the whole instrument. A log completed after processing is, as Part VI puts it, a memoir — and the two quantities the season is for cannot be got out of a memoir.

EX-3 is the collation sheet, twenty rows to a page, and a season of assignments will fill three or four of them. EX-4 is where the season pays: the plot of the time that worked against the time you computed gives an effective speed in its intercept and a reciprocity exponent in its slope, and neither is published by anybody for your material in your processing.

Printing, versions, and why nothing on a sheet explains anything: see printable worksheets.

Pure Silver · The exposure log

EX-1

One exposure — before the shutter opens

One sheet, plate or frame. All of it is a prediction.

Before the shutter opensbefore

Identifierdate and sheet number, as on the sleeve
Date and time
Assignment or session
Camera and configuration
Pinhole plate, from the register
Measured focal distance fmm
Effective aperture Nf/
Extension factor applied(f actual / f assumed)²
Subject
Material, and the effective ISO it is taken at
Metered lightthe reading with its f-number and speed, lux, or a named row
Computed exposure t, before any corrections
Filter, and its factor for this material and this light
Reciprocity correction, and the sheet and edition it came from
Time actually given, and the brackets

The predictionbefore

Intention — what a viewer should notice, and what you expect the medium to do to it
Predicted rendering of anything that moves — the fraction of the exposure it is present for, and the tone
Pure Silver · The exposure logEX-1 · v1.0 · sheet 1 of 4puresilver.runbook.academy/worksheets/exposure-log/

Pure Silver · The exposure log

EX-2

One exposure — after processing

The same sheet, once it is dry. Print it on the back of EX-1.

Where you control the light — the still-life assignment adds thesebefore

Illuminance at the set, what measured it, and where the meter lay
Subject-to-pinhole distance of each object, and its predicted image height
Measured brightness rangeas a ratio and in stops
Lamp, by type and wattage

After processingafter

What moved in the frame, and for how long
Processing — developer, dilution, temperature, time, agitation
Result against the printed grey scalethin / right / dense
Where the shadows and the highlight sat
What to change next time, with a number in it

The reconciliationafter

Clause by clause — which parts of the intention happened, and which did not
Which prediction was wrong, in the words you wrote before the exposure
Pure Silver · The exposure logEX-2 · v1.0 · sheet 2 of 4puresilver.runbook.academy/worksheets/exposure-log/

Pure Silver · The exposure log

EX-3

The collation sheet

Twenty exposures, five columns. Print as many as the season needs.

The set these rows belong to

Material, and the speed assumed for the computation
Sheetof
The processing these rows share

The rows

IdentifierIlluminance E, measured or estimatedluxEffective f-number NComputed timesTime actually givensJudged resultthin / right / dense
Pure Silver · The exposure logEX-3 · v1.0 · sheet 3 of 4puresilver.runbook.academy/worksheets/exposure-log/

Pure Silver · The exposure log

EX-4

The two numbers, and what the set says about the camera

One season's collation, read off the plot.

Read off the log-log plotafter

Points plotted, log₁₀ of the time given against log₁₀ of the time computed
Intercept, log k
Slope, P — the reciprocity exponent
Uncertainty of the intercept
Uncertainty of the slope
Effective speed, the assumed speed divided by kISO
The processing these two numbers apply to

Faults that recur across the whole setafter

The fault, and how many sheets carry itWhat it points toThe build change
Pure Silver · The exposure logEX-4 · v1.0 · sheet 4 of 4puresilver.runbook.academy/worksheets/exposure-log/

Where the fields come from

Every field on these sheets is one a written page of the course asks you to record. Those pages are linked here, and the build fails if one of them stops existing.

What these sheets do not carry

  • The camera fields do not apply to a contact-printed photogram. Part I's first log is an exposure series against a light source, and the identifier, light and result blocks are what it needs; leave the plate, the focal distance and the aperture empty rather than inventing a value for them.