Stacker manual

Capture

Capture drives a connected OM System camera from inside Stacker: live view on screen, focus under your control, exposure set once for the whole stack, and the focus bracket fired from the panel. Every captured image lands in a folder you choose and is imported automatically, so when the bracket is done the Images step is already filled.

You do not have to use it. A bracket shot with the camera alone, or with a rail, imports the same way through File ▸ Import. Capture earns its place when you are at the bench with the camera on a tripod and want to see the result as you work: you can check focus on the first frame before you fire, let Stacker hold the exposure steady, and have the next step waiting the moment the camera stops.

The panel at the right is one section per job, top to bottom: Camera, Status, Focus, Capture mode, Exposure, Shoot, Calibrate colour and Camera settings. Only Camera is shown until a camera is connected; the rest appear once one is. The connect, disconnect, fire and single-shot commands are also in the Camera menu (Connect Camera, Disconnect Camera, Fire Bracket, Single Shot), so you can fire from the keyboard without the panel.

Connecting a camera

The Camera section picks the body, picks the link, and connects. Until a camera is connected the picture area reads No camera connected with the hint Join the camera’s Wi-Fi network, then press Connect in the panel. Once connected, the title of the section carries a Connected chip, the picture area shows Waiting for live view… for a moment, and then live view.

The first control is the body. The list holds OM System OM-1 Mark II and Other OM System / Olympus body. Under it a badge says how far that choice is trusted:

Pick the body you have. The picker and the link lock while connected; disconnect to change them. Your choice is remembered for the next launch.

Why. Stacker asks the body for its settings by number, and the numbers it knows are the OM-1 Mark II’s. An experimental body may lack some of them; where it does, the panel shows a dash instead of a control rather than guessing.

USB and Wi-Fi

Two segments under the picker choose the link. Both lock while connected.

USB is the simplest. Plug the camera in and set its USB Mode to RAW/Control; in Storage mode it appears as a card reader and cannot be controlled. Stacker checks the cable once a second while you are disconnected and says what it found in the line under the segments, so you know before pressing Connect:

Wi-Fi uses the camera’s own network. Join it from your computer first, the way the camera’s phone app does, then press Connect. The Host field holds the camera’s address. It is filled with the usual one (shown greyed when empty) and rarely needs changing; if your camera is on a home network instead of its own, put its address there. The first seconds after switching networks often fail with no route yet; Stacker retries a few times by itself before it gives up. On macOS 15 and later the first connection also brings up a system dialog asking whether Stacker may find devices on your local network; click Allow, then press Connect again.

Connect fills the width of the panel. While it works the status row under it shows a busy dot and Connecting…, or whatever the camera is doing. On success the row reads Connected · live view {quality} with the live-view size the camera agreed to; on failure it turns amber with a one-line headline and a Details link that opens the whole message. Once connected the button becomes Disconnect, with a quiet Power off beside it that switches the camera off from the desk.

Tip. Pressing the shutter on the body while it is tethered does not lose the shot. Frames waiting in the camera when you next fire from Stacker are saved to the capture folder, with the note Saved {n} earlier shots from the camera, but they are not added to the stack.

Waking the camera over Bluetooth

A camera that has gone to sleep takes its Wi-Fi network down with it. Over Bluetooth, Stacker can wake it so the network comes back; Bluetooth does nothing else, and it is only offered while you are disconnected on the Wi-Fi link, under the disclosure Wake over Bluetooth.

Open it and fill in Name (as the camera shows it, for example OM-1MII) and Passcode. Both come from the camera’s own Wi-Fi/Bluetooth settings, and they are remembered once you have used them. Wake camera sends the wake-up; the status row reports what happened. Then join the camera’s Wi-Fi as usual and press Connect.

When the connected body is not the one selected

Stacker asks the camera what it is. If the answer differs from the model you picked, an amber line says The connected camera is {model}. with a Use {model} button beside it. Press it and the panel switches to the body actually on the cable; you keep the connection.

Status

Under the model’s name, four facts read straight from the camera, with a dash where the body has not reported one:

Why. A stack can take minutes, and a body that dies halfway through leaves you with half a bracket and no way to match the second half to the first. The battery is the one fact worth reading before every long run.

Focus

The four arrow buttons step the lens by hand: « and ‹ move focus nearer, › and » farther. The single arrows are a fine step, the double arrows a coarse one, in the lens’s own focus-step unit: a fine nudge is 3 units and a coarse one 14. They work in any focus mode.

Clicking the live view autofocuses at that point. Stacker waits up to a few seconds for the lens to lock and reports in the status row: Focused, or The camera couldn’t lock focus there — try a spot with more detail, or check the lens isn’t set to MF. The point you focus on also tells automatic exposure where the subject is.

A row under the hint always reports the focus mode. Autofocus ready means the body is in an AF mode. If the body is in manual focus (or Preset MF) the row turns amber: The camera is in manual focus: tap-to-focus, Measure range and refocus-on-fire can’t run. and a Switch to AF button appears. It sets the camera’s focus mode to its first AF mode.

Why. Stacker puts the body in manual focus for every bracket it drives, so that nothing refocuses between frames, and puts the mode back afterwards. A crash, or a cable pulled mid-run, can leave the body in manual focus. Switch to AF is the one-click way back.

Focus map and peaking

Focus map tints the parts of the live view that are sharp right now: Stacker’s own focus peaking, drawn on the live-view picture, since the camera’s own peaking never reaches the tethered feed. It is off by default because scoring every frame costs a little work; switch it on while you set up and off if live view feels slow.

Below the checkbox, four segments choose the tint, Red, Yellow, White or Blue; pick one that stands out against your subject. The Peaking slider decides how far below the sharpest area still lights up: Lower lights more of the picture; higher keeps only the sharpest. A frame with nothing sharp in it lights nothing. The colour and threshold are shared with the Touch up step’s overlay and with Settings › General, so a choice made here follows you.

Tip. With the map on you can see where the first frame of the bracket will be sharp before you fire. That is the single most common thing to get wrong: a bracket that starts behind the nearest detail never gets it, and nothing later can put it back.

Capture mode

Two segments decide who drives the bracket. The choice also picks which exposure program runs, so choose the mode before you worry about exposure.

Live subject

One press, and the camera’s own Focus BKT shoots the whole stack as fast as the body can; the whole bracket is over in a second or two. The panel shows the camera’s own bracketing settings as four rows, each editable here and sent to the body as you change it:

A row shows a dash when the body does not report that setting. Under the rows one line says what the next press will do: Set Focus Bracketing on the camera; one press fires the burst. when the body reports none of these settings, or Focus BKT is off — the camera will take a single image. when it is switched off.

Autofocus when firing decides where the burst starts. Off: the burst starts exactly where focus is now (tap the nearest detail first) with no AF pause. On: the camera refocuses first. It is off by default. With it off, Stacker switches the body to manual focus for the burst so the camera cannot move focus on the press, and switches it back when the burst is over. With Focus BKT on, Stacker knows how many frames to expect and keeps collecting until the last one lands, however slowly a recycling flash spaces them.

Why. The camera’s drive is faster than anything Stacker can do over a cable, and for a subject that may walk off, speed is everything. The price is that the step size is on the camera’s scale, not the lens’s, so the exact spacing of the frames is not known.

Still life

Stacker fires, confirms the frame reached the camera’s memory, downloads it, steps the lens toward far by a known amount, and repeats. Every frame is confirmed before the next, because a press sent while the body is still busy is silently dropped. The run is slower, but the step size is exact and the bracket never outruns the card. The whole bracket runs in manual focus; Stacker switches the body to it when the run starts and puts the previous mode back when it ends. Start focused on the nearest detail: the run walks backward through the scene from wherever focus is when you fire.

• Images sets how many frames to shoot, from 3 to 300; 15 to begin with.
• Step is the lens’s own focus-step unit per frame, from 1 to 20; 5 to begin with. Smaller steps give a denser stack. The run stops early at the lens travel limit and keeps what it captured. The focus arrows above use the same unit, so a fine nudge (3) and a coarse one (14) give you a feel for it.
• When the open stack already carries lens data from its RAW files, a line under the slider reads The open stack’s lens and aperture suggest {step} for 70% slice overlap. That is the step that would put each frame’s zone of sharpness 70 % over its neighbour’s, measured from the bracket you already have.

Why. Adjacent frames must overlap in sharpness or the stack has a soft band between them that no engine can fill. Seventy percent overlap is comfortable; a step that puts the slices edge to edge leaves no margin for a lens that steps unevenly.

Measure range takes the guessing out of Images. Three buttons sit under the sliders:

1. Press Pick near, then click the nearest detail of the subject in the live view. The line under the buttons reads Click the nearest detail in the live view. until you do; a green N marks the point.
2. Press Pick far, then click the farthest detail; an orange F marks it. Both buttons show a tick once their point is set.
3. Press Measure range. It is dark until both points are set, and it needs the body in an AF mode.

Stacker autofocuses on the near point, switches the body to manual focus, and steps the lens toward far a few units at a time, scoring how sharp the far point looks after each step. The far point is sharpest when its own focal plane arrives, so the peak of that curve is the range. The lens is then driven back to the near point, ready to shoot, and the line reads Range {units} focus units → {frames} images at step {step}. The image count is set for you: the range divided by the step, rounded up, plus one, so the first frame sits on the near point and the last at or past the far one. Change Step afterwards and Images follows. Picking either point again clears the measurement.

Pick points with texture or an edge. The scan tells you when it cannot measure:

Exposure

Two segments, Auto and Manual, decide who sets shutter and ISO. Aperture is always yours: stacking is what buys the depth of field, so the lens stays at the f-number you chose. Three rows follow, Aperture, Shutter and ISO, each an editable copy of the camera’s setting; under Auto the shutter and ISO rows are greyed because Stacker owns them.

Auto is the default and the recommended choice: Stacker reads the live view and sets shutter speed and ISO so the subject sits in the middle of the exposure, then holds them for the whole stack so every image matches. It meters the live view a few times a second, weighted to the centre of the frame and more heavily to the point you last focused on, and aims the subject at middle grey. Shiny shells and metal must not blow out, so while highlights clip it pulls the exposure down, by up to one stop. Small errors are left alone; chasing them would make live view flicker. Which of shutter and ISO moves depends on the capture mode:

The exposure is set before the bracket, never during it. When you press Fire bracket, Stacker first gives a correction in progress a moment to finish, then fires with the settings as they stand, and the camera holds them for every frame.

Why. Every frame of a bracket must be exposed the same. An exposure that drifts between frames shows up in the stack as patches of different brightness along the seams between frames, which no engine can hide. Auto measures once and locks; the camera’s own auto-exposure would meter every frame afresh.

Manual leaves shutter and ISO to you and shows the meter. Auto also hands over by itself: if you turn a dial on the body while Auto is on, the panel switches to Manual and says so, Exposure changed on the camera — switched to Manual. Press Auto to take it back.

Under the rows a small histogram shows the brightness of the live view; its right edge turns amber when more than a sliver of the subject clips. The line beneath it reads the current ISO, shutter and aperture, then a verdict:

Exposure limits

The subgroup under the meter holds the three limits automatic exposure works within. It is greyed under Manual.

• Highest ISO: the most ISO Auto may use, one of 400, 800, 1600, 3200, 6400 or 12800. Live subject starts at 3200, still life at 1600, and each mode remembers its own. ISO 200 is the cleanest. Higher ISO brightens a dim scene at the cost of grain; the OM-1 II stays clean to about 3200.
• Slowest shutter: 1/125, 1/250, 1/500 or 1/1000, with 1/250 to begin with. Live subjects move: slower than this and legs and antennae blur. 1/250 suits most insects at rest. It is greyed in still life, where the shutter may run to four seconds.
• Brightness: −1 to +1 EV in thirds of a stop, 0 to begin with. For subjects that aren’t mid-toned: lower it for a dark beetle so it stays dark, raise it for a white flower so it stays white. Auto aims at middle grey; this tells it the subject is not.

Shoot

Settle waits a chosen number of seconds, 0 to 10, before the first shot so vibration from touching the rig dies down: Vibration decay before the first shot — rails and rigs vary. Three seconds to begin with. In live subject with Focus BKT off, Stacker also waits at least this long, and never less than four seconds, for the camera to go quiet before it decides the burst is over.

Fire bracket runs the bracket as Capture mode defines it: the camera’s own Focus BKT burst in live subject, Stacker’s stepped run in still life. While it runs the step card at the top shows Capturing {count}, as {done}/{total} with a progress ring and a time estimate when the total is known (Focus BKT on, or still life) and as a plain count otherwise, and the status row under Connect reports Firing shutter… or Capturing frame {i}/{n}…. The buttons go dark until the files have landed.

Single shot fires the same capture with a fixed two-second settle in place of the Settle slider. In live subject with Focus BKT off that is one image, which is the usual reason to press it: a test frame to check exposure or framing before the bracket.

Save to… picks the folder the RAW files are downloaded to; the path shows beside the button and is remembered. Until you have chosen one the line reads Save folder: ask on first capture, and the first Fire bracket asks. Captured images import automatically. When they arrive the status bar reads Imported {n} captured images, the step card counts them ({n} captured), and the Images step is ready. In free mode the limit on images applies to captured ones as well; what did not fit stays in the folder.

Tip. Each frame’s download is confirmed before the next step in still life, so the run is only as fast as the camera writes and sends. A fast card and USB make a real difference to a 100-frame bracket.

Calibrate colour

Two one-frame captures that are measured rather than stacked. Both use the camera’s focus as it is (autofocus runs if the body is in an AF mode), settle for two seconds, and need a RAW file: if the camera sends only a JPEG the panel says The camera sent no RAW file; a colour target needs one. Set the body to RAW and shoot again. (or the same for a flat field). They are made here, on the Capture step, because this is where the camera, the lens and the light are all set up as they will be for the stack; they are used later, under Images › Camera develop.

Shoot colour target: Put a ColorChecker Classic in the light the stack will use, fill the frame with it, and shoot one RAW. It opens in the Calibrate colour window instead of joining the stack. The status bar reads Captured the colour target and the window opens with the image. Drag its four corners onto the chart’s outer corners, press Read chart, and the window shows how far each patch is from its true colour before and after the fit. Give it a Profile name and a Lighting note (Studio LED, window light…). Save profile keeps it for this camera; it is offered under Camera profile in Camera develop from now on. Apply to this stack develops the open stack through it, with the chart’s neutral as white balance; a re-develop applies it.

Shoot flat field: For the lens’s vignetting: fill the frame with an evenly lit plain surface at the stack’s focal length and aperture and shoot one RAW. It is measured, not stacked, and offered under Flat field for this lens and setting. The status bar reads Captured the flat field, then Flat field measured: with its name, the lens, the focal length, the f-number and how many stops the corners fall off. It becomes the open stack’s flat field at once and is kept, so Camera develop’s Flat field list offers it whenever the reference image was shot with the same lens at the same setting.

Why. A colour profile and a flat field are only right for the camera, lens, aperture and light they were measured under. Shooting them from the same tethered setup, moments before the bracket, is the surest way to have them match.

All camera settings

The Camera settings section reports how many settings the body offered ({n} settings) and the button All camera settings… opens a window listing every one: Straight from the camera; changes apply to the body immediately. Each row has the setting’s name, its code, and an editor: a dropdown for a list of allowed values, a drag value for a range (sent when you release it), or a greyed label when the camera does not let it be changed. Settings changed on the body itself update in the list as the camera reports them.

• Search settings narrows the list by name or code.
• Changeable only hides the read-only ones.
• Refresh reads the whole list again.
• Copy report puts the lot on the clipboard, for a bug report about an experimental body.

Tip. The panel’s own rows, Focus BKT, aperture, shutter and ISO, are the same settings; this window is for the rest, and for finding out what an untested body reports.

Status messages on this step

The status bar reads Join the camera’s Wi-Fi, then Connect · click the live view to move AF whenever Capture is the current step.

The step card reads No camera — connect in the panel at right until a camera is connected, Connecting… while one is, and Connected · {model} · {n} captured once it is; its detail line carries the camera’s latest message. While a capture runs it becomes a progress card, Capturing {done}/{total}, or Capturing {done} when the total is not known.

The status row in the Camera section reads Not connected, Connecting…, Connected · live view {quality}, Disconnected, or the last error’s headline in amber with a Details link; while the camera works it carries its progress: Focusing on the near point…, Scanning focus… {n} units, Firing shutter…, Capturing frame {i}/{n}…, Saved {n} earlier shots from the camera.

The status bar confirms what arrived: Imported {n} captured images, Captured the colour target, Captured the flat field, Flat field measured: {what}, Profile saved, and after a scan Range {units} focus units → {frames} images at step {step}.