How to Photograph Rashes for Telehealth: Lighting & Angles

Direct Answer

To photograph a rash for telehealth, use natural daylight (near a window, no direct sunlight), hold your phone 6–12 inches from the rash, turn off the flash, and take both a close-up shot showing texture and a wider shot showing where the rash is on your body. The single biggest mistake patients make is using flash or bathroom overhead lighting, which washes out the redness and flattens the texture that allergists need to see. Good photos let your board-certified allergist evaluate your skin as accurately as an in-person visit.

Why Photo Quality Matters for Allergy Diagnosis

When your allergist evaluates a rash in person, they assess color (redness, purple, pink), texture (raised, flat, scaly, smooth), distribution (clustered, scattered, along a contact line), and pattern (round welts for hives, linear scratches for dermatographism, patchy for eczema). In a telemedicine visit, your photos and video must convey these same details.

A study in the Journal of the American Academy of Dermatology found that diagnostic accuracy in teledermatology is strongly correlated with image quality. Poor lighting, blurry images, and incorrect framing were the most common reasons for inconclusive remote evaluations. The good news is that a modern smartphone camera is more than capable of producing diagnostic-quality images—you just need to know the technique.

The 7-Step Photo Checklist

Step 1: Find Your Light Source

Natural daylight from a window is the best light for skin photography. Position yourself so the light falls evenly across the rash. Face the window at a slight angle (about 45 degrees) rather than directly facing it, which can create shadow-free flat lighting that hides texture.

Step 2: Turn Off the Flash

This is the single most important technical step. Open your phone camera app, find the flash icon (usually a lightning bolt symbol), and set it to OFF—not "auto." Auto flash may fire unexpectedly in a slightly dim room and ruin your image. The flash creates a white-hot spot that eliminates the redness your allergist needs to see.

Step 3: Stabilize Your Phone

Blurry photos are the second most common problem. Skin texture, individual bumps, and scale cannot be evaluated if the image is not sharp. To stabilize:

• Rest your elbows against your body or a surface
• Hold the phone with both hands
• Tap the screen to focus directly on the rash (not the background skin)
• Hold your breath briefly when pressing the shutter
• If photographing your own arm or leg, prop your phone against a stable object and use the self-timer (3-second delay)

Step 4: Take the Close-Up Shot (6–8 inches)

Hold the phone 6–8 inches from the rash. Tap the rash area on your screen to lock focus there. This shot should fill most of the frame with the affected skin. Your allergist will use this image to evaluate:

• Whether the bumps are raised (papules), flat (macules), or fluid-filled (vesicles)
• Skin texture—smooth, scaly, cracked, weeping
• The borders of individual lesions—well-defined (hives) or diffuse (eczema)
• Color variation—central clearing (ringworm), blanching (hives), purplish tone (vasculitis)

Step 5: Take the Overview Shot (12–18 inches)

Pull back to 12–18 inches and capture the rash in context with surrounding normal skin and recognizable body landmarks (elbow crease, neckline, waistband). This shot tells your allergist:

• Where on the body the rash is located (critical for diagnosis—contact dermatitis follows exposure patterns)
• The distribution pattern—scattered, clustered, bilateral, following a dermatome
• How much total body area is affected
• Whether the rash crosses skin folds or avoids them (diagnostically significant)

Step 6: Add a Size Reference

Place a coin (quarter or dime), a ruler, or your index finger next to the rash in at least one photo. Without a reference, your allergist cannot tell if a bump is 2 mm or 2 cm. This simple step eliminates guesswork.

Step 7: Document the Timeline

Take photos at multiple time points if possible:

• When the rash first appears — Captures initial presentation
• At peak severity — Shows the worst of the flare
• As it resolves — Residual discoloration or scaling provides diagnostic clues
• After it disappears — If the rash comes and goes (common with hives), a photo of normal skin between flares is also useful

Timestamp every photo. Most phone cameras embed the date and time in the image metadata, but write the date and time in your phone’s notes app as well in case your allergist asks.

Special Situations

Photographing Hives (Urticaria)

Hives are particularly challenging because they can appear and vanish within hours. The moment you notice a hive flare, photograph it immediately—even if your appointment is not for days. A photo from three days ago is far more useful than trying to describe hives that are no longer visible. If you can, take a short video panning slowly across the affected area, as hives often cover a large body surface.

Photographing Eczema

Eczema has subtle texture changes (dryness, lichenification, fine cracking) that require good close-up focus. Make sure your close-up is sharp enough to see individual skin lines. A slightly angled light (side lighting from the window) will reveal the raised, rough texture of eczema patches better than flat, front-on lighting.

Photographing on Darker Skin Tones

Rashes on darker skin tones can appear more purple, dark brown, or grey rather than the classic "red" described in most textbooks. Phone cameras sometimes auto-adjust in ways that mask these subtle color changes. Tips:

• Make sure the camera is exposing for the skin, not the background—tap on the skin and hold to lock exposure
• Avoid backgrounds that are much lighter or darker than the skin (white walls or dark fabrics), which cause the camera to over- or under-expose
• Take multiple shots with slightly different angles to capture how light interacts with the affected area
• Mention your skin tone to your allergist at the start of the visit so they calibrate their assessment

What Your Allergist Needs to Know Beyond Photos

Photos are essential, but your allergist will also need this context during your telemedicine visit:

• When the rash started — Hours, days, or weeks ago?
• What you were doing before it appeared — New food, new product, outdoor activity, medication change?
• Does it itch, burn, or hurt? — Itching suggests allergy/eczema; burning suggests irritant or infection; pain suggests deeper inflammation
• Does it come and go or stay constant? — Hives cycle within hours; eczema persists; contact dermatitis stays as long as exposure continues
• Any known allergies or triggers? — Share your full allergy history
• What you have already tried — Over-the-counter creams, antihistamines, home remedies

When to See an Allergist

You should book a telemedicine consultation with a board-certified allergist if:

• You have a recurring rash that you suspect is allergy-related (hives, eczema flares, contact dermatitis)
• Your rash comes and goes and you have not identified the trigger
• Over-the-counter antihistamines and hydrocortisone are not providing adequate relief
• You have a rash combined with other allergy symptoms (nasal congestion, sneezing, asthma)
• You need to identify whether environmental allergens (pollen, dust mites, pet dander, mold) are contributing to your skin symptoms
• You want to explore sublingual immunotherapy (SLIT) to reduce the allergic inflammation that drives eczema and hive flares

Frequently Asked Questions

Do I need a special camera to photograph rashes for telehealth?
No. Any modern smartphone camera (iPhone or Android from the last 5–6 years) produces images with enough resolution and color accuracy for teledermatology. The technique—lighting, distance, and focus—matters far more than the camera hardware. No special apps or lenses are needed.

Should I use my phone’s zoom feature for close-ups?
Avoid digital zoom, which degrades image quality. Instead, physically move the phone closer to the rash (6–8 inches). If your phone has an optical zoom or macro lens mode (many newer phones do), that can produce excellent close-ups without quality loss. Otherwise, just get close and let the camera focus naturally.

What if my rash disappears before my appointment?
This is very common with hives. Photograph the rash immediately when it appears, regardless of when your appointment is scheduled. Show these timestamped photos to your allergist during the visit. Even photos from days or weeks earlier are valuable. Your allergist can diagnose from photos plus your history even if the rash is not visible at the time of the visit.

Can I send photos to my allergist before the appointment?
At HeyAllergy, you can share photos during your secure video visit or upload them through the patient portal when completing your new patient registration. Having photos ready before the visit starts makes the consultation more efficient.

How many photos should I take?
Aim for 4–6 photos per affected area: one close-up, one overview, one with a size reference, and additional shots showing any variation in appearance (different angles, different times of day). More is better—your allergist will select the most diagnostically useful images.

Will my allergist be able to diagnose my rash accurately through telehealth?
For most allergy-related skin conditions (hives, eczema, contact dermatitis), telemedicine with good-quality photos is highly effective. A study published in JAMA Dermatology found that teledermatology diagnostic concordance with in-person evaluation exceeds 80% when image quality is adequate. If your allergist determines that an in-person exam is needed, they will refer you to a local specialist.

Author, Review and Disclaimer

Author: Krikor Manoukian, MD, FAAAAI, FACAAI — Board-Certified Allergist/Immunologist
Bio: Dr. Manoukian is a board-certified allergist/immunologist with over 20 years of experience. He leads HeyAllergy’s clinical team and specializes in telemedicine-enabled allergy care and personalized sublingual immunotherapy programs.
Medical Review: HeyAllergy Clinical Team (Board-Certified Allergists/Immunologists)
Disclaimer: This article is educational and not a substitute for medical diagnosis. If you have a rash with fever, spreading redness, pus, difficulty breathing, or facial/throat swelling, seek emergency medical care immediately rather than waiting for a telehealth appointment.

References

• AAAAI, Telemedicine for Allergy/Immunology. AAAAI
• Finnane A, et al. Teledermatology: image quality and diagnostic concordance. JAMA Dermatology. 2017;153(12):1243-1248.
• Ashique KT, et al. Clinical photography in dermatology: best practices and guidelines. Indian Dermatology Online Journal. 2015;6(3):172-178.
• American Telemedicine Association, Practice Guidelines for Teledermatology. ATA, 2016.