Locate the error before changing settings.
Keep your originals and compare at actual pixels, not only a fit-to-window preview. In Nightscape Stacker, use Check sharpness at 100% or 100% check. Also open the exported TIFF in your editor.
| What you see | Compare first | Next test |
|---|---|---|
| Double or soft stars across the frame | Individual inputs and stack at the same scale. | Choose a sharper reference; exclude poor frames. |
| Sharp center, poor corners | Each input corner against its matching output corner. | Try a shorter sequence with fewer consecutive frames. |
| Bright seam or ghosted ridge | The sky mask against branches and terrain. | Erase foreground from the sky selection, then rerun. |
| Trails or moving cloud | Find the affected input frames. | Exclude them manually in this beta. |
| Rejected files or odd colors | Format, profile and matching dimensions. | Convert and re-export a compatible sequence. |
| Sky improves, ground stays noisy | Ground in the reference and result. | Expected here: the foreground is one reference frame. |
A successful processing status or low global alignment residual does not prove that every corner and boundary is correct. Inspect the region that matters in your final crop.
01 / Input or alignment?
Double stars throughout the image.
- Inspect the inputs first. Compare a few individual frames at 100%. If every input already has blur, camera shake or visible trails, a stack cannot recreate missing point-star detail.
- Choose a clear reference. In the beta's Foreground column, select a frame with sharp stars and a sharp foreground. This photo is also the alignment reference.
- Check the included sequence. Keep the framing, focal length, exposure settings, orientation and pixel dimensions consistent. Remove cloud-covered, shaken or missed-focus frames.
- Retry a small group. Use 3–5 consecutive suitable frames and a mask containing clear sky. At least three frames, including the reference, must pass alignment.
Download the processing report and read rejected-frame reasons. Do not include ground in the sky mask merely to increase the selected area. If good inputs still produce doubled stars, retain the report and comparison crops rather than assuming the stack is usable.
02 / Beyond the center
The center is sharp, but the corners are not.
First compare the same corner in an individual frame and the stack. A star that is already stretched in the input needs a different diagnosis from a single input star becoming two in the output.
Wide-angle distortion can cause alignment errors that are more visible toward the corners. Sequator's official manual describes distortion-related false trails and provides dedicated distortion options. That explanation does not establish that every stacking engine can correct every lens.
- Inspect Center, Top left, Top right, Bottom left and Bottom right in the beta's actual-pixel inspector.
- As a controlled test, shorten the time span using fewer consecutive frames, then compare the same corner again.
- Check that the reference is sharp and the selected sky contains enough clear stars.
- Inspect the final TIFF too; a downsampled preview can conceal a small double image.
The current browser beta cannot promise to model every severe lens distortion or weakly constrained region. If the short-sequence test still fails, do not keep adding frames. You may need a different capture sequence or a tool with appropriate distortion controls.
Follow lens-preparation advice for your chosen stacker. Do not apply or remove lens correction as a universal fix: software requirements differ. Compare preparation requirements.
03 / Sky meets landscape
A bright seam, duplicated ridge or messy tree edge.
Look at where the error follows the boundary. If terrain or branches were selected as sky, the stacking transform can bring foreground detail into the wrong place.
- Return to the manual mask and zoom in.
- Use Eraser to keep ridges, trunks and branches out of the green sky area.
- For the first test, leave tiny gaps between leaves as reference pixels. This beta does not automatically segment fine branches.
- Rerun and inspect the same boundary in the downloaded TIFF.
The mask is edited at preview resolution. Near unsafe boundaries and regions without enough safe overlap, the engine can retain reference pixels. Those regions may remain noisier than the central stacked sky; drawing a more ambitious mask does not guarantee a clean result.
Complex trees are a demanding task across workflows: Starry Landscape Stacker's developer documents extra masking work around tree gaps. That is a reason to inspect carefully, not evidence that our manual mask performs better.
04 / Transient objects
Clouds, satellites or aircraft remain.
The current beta averages accepted sky samples in linear light. It does not automatically reject moving clouds, aircraft trails, satellite trails or other transient objects.
Find and uncheck affected frames before processing. If the selected reference is affected, choose another foreground/reference frame first. Keep at least three suitable frames that can pass alignment.
If too few clear frames remain, use a different sequence. Adding more contaminated frames is not a reliable repair. A workflow with explicit outlier rejection may be more suitable when manual exclusion cannot solve the problem.
05 / Import and color
A file is rejected, or the color looks wrong.
For this beta, start from matching rendered sRGB files: JPEG, PNG or supported single-page, opaque RGB TIFFs, with no frame larger than 32 MP. Camera RAW and DNG need to be developed and exported first.
- Use matching pixel dimensions, crop and orientation across the sequence.
- For TIFF, use 8 or 16 bits per channel and a supported uncompressed or ZIP-compressed strip variant. LZW, tiled, alpha-channel and BigTIFF variants are not supported.
- Use normal SDR export and the standard embedded sRGB profile. These are this beta's compatibility requirements.
- If a profile is rejected, convert and re-export from your originals. Deleting or relabeling a profile is not a color conversion.
The on-screen actual-pixel inspector displays an 8-bit representation of a crop. Check the downloaded 16-bit sRGB TIFF in your editor for final color and tonal decisions. Exporting an 8-bit JPEG source as 16-bit TIFF does not recreate the original RAW precision.
Lightroom Classic export checklist → · Full file requirements →
06 / Expected behavior
The ground is still noisy.
In Nightscape Stacker's current beta, the foreground comes from one reference photo. The sky is aligned and averaged; the ground is neither stacked nor denoised. A visible difference between sky and ground noise can therefore be expected.
Select your best suitable foreground reference, but do not expect this version to blend a separate blue-hour exposure or average multiple ground frames. If those are essential to the photograph, use a workflow that supports them.
Keep enough evidence to get help.
Save the project, the matching input files and the processing report. A project keeps the mask and settings; it does not contain the photos. Note which controlled change you made and whether the same center, corner or horizon crop improved.
For support, email contactjensennow@gmail.com with your browser version, file format, dimensions, frame count and failed step. If you include a processing report, review it and redact filenames or private details before sharing. Private originals are not needed in the first message.
Run a small, inspectable first test.
Use a clear fixed-tripod sequence and a simple horizon. Full-resolution TIFF export is free during beta; general sales are not open yet. A successful run still needs an actual-pixel check.
Open the free browser stackerOfficial background: Sequator manual: distortion and corner errors; Starry Landscape Stacker: tree gaps and masks. Checked October 11, 2026.