Field Utilities · Est. 2020

Astrophotography & Timelapse Calculator

Precision exposure timing for pinpoint stars across Sajek, Saint Martin, Teknaf, and the Bandarban hill tracts. Calculate NPF shutter speeds, plan Milky Way timelapse intervals, compute ND filter times, find moon-free dark windows, and scout light pollution across Bangladesh.

01. Pinpoint Stars & Milky Way

Shutter Speed Calculator

Determine the maximum untracked exposure time before star trailing becomes visible on your sensor, using the NPF rule — the accurate standard for modern high-resolution sensors.

Camera & Lens Parameters

Auto-filled by camera preset, or enter manually for custom sensors.

Recommended Exposure Times

The NPF rule gives pinpoint stars; the relaxed value trades a touch of trailing for more light on the Milky Way core.

NPF Rule (Pinpoint Stars)
11.0 s

Zero perceptible star trailing at 100% zoom.

NPF Relaxed (Slight Elongation)
15.4 s

Balanced light gathering for Milky Way core detail.

02. Motion & Sequence

Milky Way Timelapse Planner

Calculate shooting intervals, total frames, total field duration, and memory card requirements for dark-sky sequences.

Sequence Settings

Recommended: 2–3s gap between exposures to prevent skipped frames.
Auto-filled from the camera preset in section 01, or set manually.

Sequence Summary & Field Requirements

Interval check: Ready for uninterrupted shooting.

Total Frames Needed
360 shots

Required images for a 15s final clip.

Total Shooting Time in Field
1h 42m 00s

Continuous camera operation under the night sky.

Minimum Safe Interval
17.0 s

Exposure time plus camera buffer write delay.

Estimated Memory Card Usage
10.80 GB

Total card space needed for RAW sequence.

03. Blue Hour & Seascape Foregrounds

ND Filter Long Exposure Converter

Compute adjusted bulb exposure times when shooting coastal foregrounds at Saint Martin, Inani, or Teknaf with Neutral Density filters.

Base Exposure & Filter Strength

Adjusted Exposure Time

Required Shutter Speed
34.1 sec

Switch camera to Bulb / Manual timer mode.

Light Reduction Factor
1024x

Stops of light blocked: 10 stops

04. Moon & Dark-Sky Window

Moon Phase & Twilight Planner

Plan moon-free shooting windows — lunar phase & illumination, moonrise / moonset, and astronomical twilight (Sun −18°) for your site and date.

Location & Date

Times in Bangladesh Standard Time (UTC+6). Computed client-side with the open-source Astronomy Engine, loaded on demand.

Night Summary

Select a site and date, then compute.

Moon Phase
—

Lunar phase for the selected night.

Illumination
—

Fraction of the lunar disc lit.

Moonrise
—

Local rise time (BST).

Moonset
—

Local set time (BST).

Astronomical Dusk
—

Sun reaches −18° — true darkness begins.

Astronomical Dawn
—

Sun returns to −18° — darkness ends.

05. Dark-Sky Siting

Light Pollution Map

Scout the darkest skies before you travel — check the Bortle rating and sky-brightness for any site in Bangladesh and beyond.

Interactive Light-Pollution Atlas

We recommend LightPollutionMap.app — a detailed, up-to-date VIIRS-based atlas. Search any location, read its Bortle class, and compare years. Opens in a new tab.

Open the Light Pollution Map

Tip: the darkest practical skies near Dhaka are in Sajek, the Bandarban hill tracts, and the Teknaf peninsula — Bortle 2–3 on a clear, moonless night.

06. Companion Apps

More Field Tools

Browser-based editing tools from the Star Party Bangladesh workshop — no install, and your images never leave your device.

Deep-Sky Stacking · Beta

Astro Lenscap

Import light, dark, flat and bias frames and stack them with GPU-accelerated processing — a full deep-sky workflow, right in the browser.

Open Astro Lenscap Photo Editor · Beta

Lenscap

Crop, straighten and refine single exposures in a fast, GPU-powered editor built for astro and landscape stills.

Open Lenscap