6. Setup and Installation
This section covers everything from unboxing to first power-on. If you've already connected the ΔStop following the Quick Start, you can skim this section and focus on the subsections that apply to your setup, particularly Placement and First-Run Check.
A video walkthrough of assembly and installation is available at https://www.youtube.com/watch?v=d-F-m982txo.
Placement
Where you put the ΔStop matters more than it might seem. The unit will spend its working life within arm's reach of your enlarger, and a few minutes of thought about placement now will save friction every session going forward.
Place the ΔStop on a stable, level surface. The faceplate should be oriented so you can read the display and reach the controls without reaching across the enlarger or crossing your arms. For most right-handed printers, this means the ΔStop sits to the right of the enlarger column. Left-handed printers may prefer it on the left. There is no technical reason to favor one side; choose what suits your hands.
Keep the unit on the dry side of the darkroom, away from trays, sinks, and wash lines. If your darkroom forces the ΔStop to share space with wet work, consider a small shelf or riser to lift it a few inches above typical splash height. A simple block of wood or a laboratory bench riser works well.
Leave a few inches of clearance behind the unit for cable management.
Avoid placing the ΔStop directly beneath a safelight or in the path of an enlarger lamp spill. The display is readable under typical darkroom lighting, but direct illumination on the faceplate can create distracting reflections.
Connecting the Enlarger
The included relay unit has four AC outlets: two normally-off, one normally-on, and one always-on. Understanding the difference is important for correct operation.
The normally-off outlets turn on when the relay activates, either continuously while in Focus mode or for the duration of a timed exposure in Test or Print mode. Plug your enlarger's power cord into a normally-off outlet so that the relay controls the enlarger lamp.
The normally-on outlet delivers power continuously but cuts off when the relay activates. This is intended for accessories that should be on when the enlarger is off. A safelight is the most common use: plug your safelight into the normally-on outlet and it will stay lit whenever the enlarger is off, then turn off automatically during an exposure.
The always-on outlet delivers power continuously regardless of relay state. Use it for accessories that should remain powered at all times.
The outlets are labeled on the panel. Take a moment to confirm the correct connections before applying power:
- Enlarger → normally-off outlet
- Safelight → normally-on outlet
- Always-on accessories → always-on outlet
If your enlarger has a dedicated lamp switch, leave it in the on position; the relay unit will handle the switching from here. If your enlarger has both a lamp switch and a focus/timer switch, set the focus switch to the "timer" or external position as specified by your enlarger's manual.
Confirm that your enlarger's power draw is within the ΔStop's rated load. Most standard darkroom enlargers are well within this range, but if you are running a particularly large or unusual enlarger head, check the specification plate on your enlarger against the rating in Section 11 before proceeding.
Connecting the Power Supply
Plug the included power supply into the Power Input on the rear of the ΔStop. Plug the other end into a grounded wall outlet.
Use the power supply that shipped with your ΔStop. The unit is designed around its specifications, and substituting a different adapter, even one with matching voltage markings, can damage the internal electronics or create a safety hazard.
If you need a longer reach to your wall outlet, use a properly rated extension cord or a surge-protected power strip rather than swapping the power supply.
First-Run Check
With everything connected, you are ready to power on the unit for the first time.
Switch on the wall outlet (or plug the power supply in if it was not yet connected). The time display should illuminate within a second or two. The initial display will show the last base time used.
Turn the Mode selector to Focus. The enlarger lamp should turn on. Turn the Mode selector to Test. The enlarger lamp should turn off, and the display should show the current base time setting.
Turn the Base Time dial clockwise, then counterclockwise. The display should update smoothly as you turn, in tenth-of-a-second increments. Turn the Test Interval dial through each position and confirm that the display updates to reflect each setting. Turn the Print Stop Select dial through its range and confirm the same.
If any of these checks fail, disconnect power and consult Section 10 (Troubleshooting) before proceeding. If the issue cannot be resolved, contact support.
Storing Your Initial Preferences
Before your first real printing session, consider storing a baseline configuration in Program Memory bank 1. A common starting point is:
Base Time: 25 seconds Test Interval: 1/2 stop Print Stop Select: 0
Press Set, then press 1. The current configuration is now stored in bank 1 and can be recalled at any time by pressing 1. This gives you a known starting point for any new negative, no matter what state the dials were left in after your last session.
You are now ready to make prints. Section 7 explains the principles behind f-stop printing for readers new to the method. Section 8 walks through each operating mode in detail.