The Sun is the most accessible astronomical object there is — it's visible every clear day, requires no dark skies or late nights, and offers a constantly changing surface of sunspots, granulation, and solar activity that rewards regular observation and photography. A full spectrum camera is an excellent tool for solar imaging, but solar photography comes with one absolute requirement that must be understood before anything else: you must never point a camera at the Sun without appropriate solar filtration in place. This guide covers everything you need to know to photograph the Sun safely and effectively. For a broader introduction to astrophotography with a full spectrum camera, read: Why a Full Spectrum Camera is Better for Astrophotography Than a Standard Camera.
Solar Safety — The Most Important Section of This Guide
The Sun emits an enormous amount of energy across the full spectrum — visible light, infrared, and ultraviolet. Concentrating this energy through a camera lens without filtration will instantly and permanently damage your camera sensor. More critically, if you look through an optical viewfinder without filtration, even for a fraction of a second, you will suffer immediate and permanent eye damage, including blindness.
There are no exceptions to this rule. There is no safe way to photograph the Sun without a proper solar filter.
The following are NOT safe for solar photography:
- Stacked neutral density (ND) filters — they do not block sufficient infrared and UV radiation
- Exposed photographic film — not reliably safe and not recommended
- Smoked glass — not safe
- Welding glass below shade 14 — not safe for optical use
- Sunglasses — not safe under any circumstances
Only use filters specifically designed and certified for solar observation. When in doubt, do not proceed.
Additionally, always use your camera's electronic viewfinder or rear screen (live view) for solar photography — never an optical viewfinder. A mirrorless camera is ideal for this reason, as it has no optical viewfinder.
Types of Solar Filter
There are two main categories of solar filter for camera use, each producing very different results:
White Light Solar Filters
White light solar filters reduce the Sun's brightness to a safe level while passing a broad range of visible wavelengths. They reveal the Sun's photosphere — its visible surface — showing sunspots, faculae (bright regions around sunspots), and the granulation texture of the solar surface.
White light solar filters are available in two main materials:
- Baader AstroSolar film — a thin, aluminised polymer film that is the most widely used material for DIY and commercial solar filters. Available in visual density (OD 5.0) and photographic density (OD 3.8). The photographic density version allows shorter exposures and is preferred for imaging.
- Glass solar filters — higher-end filters using optical glass with a metallic coating. More durable than film filters and often produce slightly better optical quality, but significantly more expensive.
Hydrogen-Alpha Solar Filters
Hydrogen-alpha solar filters are a completely different category of filter that transmits only a very narrow band of light centred on the hydrogen-alpha wavelength at 656.3nm. This reveals the Sun's chromosphere — the layer above the photosphere — showing features that are completely invisible in white light:
- Solar prominences — vast arcs and loops of plasma extending from the solar limb, often many times the size of the Earth
- Filaments — prominences seen against the solar disc, appearing as dark, thread-like structures
- Plages — bright regions of the chromosphere associated with magnetic activity
- Spicules — fine, hair-like jets of plasma covering the solar surface
- Solar flares — sudden, intense brightenings associated with magnetic reconnection events
This is where a full spectrum camera has a particular advantage for Hα solar imaging. Because a full spectrum camera has full sensitivity at 656.3nm — unlike a standard camera whose IR cut filter suppresses Hα — it produces significantly better results with Hα solar telescopes and filters.
Equipment for Solar Photography
White Light Solar Setup
- Full spectrum mirrorless camera
- Telephoto lens or telescope — a longer focal length reveals more solar detail. A 300–600mm telephoto lens is a good starting point. For lens recommendations, see: The Best Lenses for Astrophotography with a Full Spectrum Camera.
- Baader AstroSolar filter cell — sized to fit over the front of your lens or telescope.
- Sturdy tripod
- Intervalometer — for capturing multiple frames for stacking
Hydrogen-Alpha Solar Setup
- Full spectrum mirrorless camera
- Dedicated Hα solar telescope — such as the Lunt LS50, Lunt LS60, or Coronado PST. These are complete instruments with the Hα etalon filter built in.
- Camera adapter — to connect your camera to the telescope's focuser
- Sturdy mount — an equatorial or alt-azimuth mount with slow-motion controls for tracking the Sun
Camera Settings for Solar Photography
- ISO: 100–400. Use the lowest ISO that gives a good exposure to minimise noise.
- Shutter speed: typically 1/500s to 1/2000s for white light imaging with Baader AstroSolar photographic density film. Adjust to achieve a well-exposed histogram without clipping.
- Aperture: for a fixed-aperture telescope, this is determined by the instrument. For a camera lens, f/8–f/11 typically gives the best optical quality.
- Format: RAW for still images. For video/lucky imaging, use the highest quality video mode available.
Lucky Imaging and Stacking
Atmospheric turbulence — the same "seeing" that causes stars to twinkle — is the primary limitation on solar image sharpness. The technique of lucky imaging addresses this by capturing a large number of short-exposure frames and selecting only the sharpest frames for stacking. For a full guide to stacking, read: How to Stack Astrophotography Images — A Beginner's Guide.
The workflow is:
- Capture a video sequence of the Sun at high frame rate (30–60fps or higher)
- Use software such as AutoStakkert! or PIPP to analyse the frames and select the sharpest percentage (typically the best 10–25%)
- Stack the selected frames to produce a single, high signal-to-noise image
- Apply sharpening using wavelets in RegiStax or similar software to bring out fine detail
What a Full Spectrum Camera Adds to Solar Photography
For white light solar photography, a full spectrum camera offers modest advantages over a standard camera. For hydrogen-alpha solar photography, the advantage is significant. The full Hα sensitivity of a full spectrum camera — compared to the suppressed Hα response of a standard camera — means shorter exposures, better signal-to-noise ratio, and more detail in prominences and chromospheric features. If you're investing in an Hα solar telescope, pairing it with a full spectrum camera makes excellent sense.
Additionally, a full spectrum camera can be used with calcium K-line (CaK) solar filters, which transmit light at 393nm in the near-ultraviolet. CaK imaging reveals the Sun's chromosphere in a different way to Hα, showing magnetic network structures and active regions with great clarity. Standard cameras have very limited sensitivity at 393nm; a full spectrum camera performs significantly better.
The Solar Cycle and When to Image
The Sun's activity follows an approximately 11-year cycle, moving from solar minimum (few sunspots, quiet surface) to solar maximum (many sunspots, frequent flares and prominences) and back. We are currently approaching solar maximum, making this an excellent time to begin solar photography — the Sun's surface is active and dynamic, with frequent sunspot groups, prominences, and flares to image.
The website SpaceWeather.com provides daily updates on solar activity, including sunspot counts, flare reports, and prominence images. It's a useful resource for planning your solar imaging sessions around periods of high activity.
Getting Started
Solar photography is one of the most accessible branches of astrophotography — it can be done in daylight, from your garden, without any special site or dark sky requirements. A basic white light setup with a Baader AstroSolar filter and a telephoto lens is an affordable entry point that can produce impressive results.
If you're interested in solar photography with your full spectrum camera and want advice on the right filter or telescope setup for your needs, get in touch — we're happy to help you get started safely and effectively.