Which camera phone ?
Any camera phone which has a light can be used to examine and document the eye....
........ however some camera phones are better than others.
Questions to ask when choosing a phone for phoneoscopy, in order of importance:
1) Distance between the light and the lens?
2) How close is the lens to the edge of the phone?
3) Will your phones software allow the light to be on continuously whilst using the camera app? (all iPhones).
4) Can you alter the intensity of the light?
5) How wide angle is the lens?
6) What is the minimum focal distance of the lens?
7) How well does the camera perform in low light ?
8) Does the camera have image stabilisation?
9) Lens quality.
10) Resolution of the camera sensor- how many megapixels can it record?
........ however some camera phones are better than others.
Questions to ask when choosing a phone for phoneoscopy, in order of importance:
1) Distance between the light and the lens?
2) How close is the lens to the edge of the phone?
3) Will your phones software allow the light to be on continuously whilst using the camera app? (all iPhones).
4) Can you alter the intensity of the light?
5) How wide angle is the lens?
6) What is the minimum focal distance of the lens?
7) How well does the camera perform in low light ?
8) Does the camera have image stabilisation?
9) Lens quality.
10) Resolution of the camera sensor- how many megapixels can it record?
The "best" iPhones for retinal phoneoscopy are:
Any iPhone 4 and above can be used to make excellent images of the fundus and anterior segment however this is my current (Mar 2019) list.The plus series (6,6s,7 and 8) all take excellent images however the position of the lenses make coaxial illumination and direct retinal examination more challenging. This does however make macro photography easier as the LED being further away from the lens allows it o be used at the same time as a macro lens which can be used to get near coaxial illumination of corneal and lens lesions.
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Equine/large animals:
1st place = iPhoneXS 2nd place= iPhone X 3rd place = iPhone XS max 4th place= iPhone SE 5th place = iPhone XR 6th place = iPhone 6s 7th place = iPhone 8 8th place= iPhone 7 |
Small animals:
1st place = iPhone XS 2nd place = iPhone X 3rd place = iPhone XS max 4th place = iPhone 4S 5th place = iPhone SE 6th place = iPhone 6s 7th place= iPhone 8 8th place = iPhone 7 |
Distance between the light and the lens. (LL distance).
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This is the critical factor when performing direct phoneoscopy.
What we are aiming for is constant illumination as close to the visual axis as possible. The shorter this distance is the more prone photographs of people in low light level are to having the "red eye" artifact, This artifact is the effect we are aiming to exploit in phoneoscopy however phone manufactures will be aiming to minimise this effect by , in general, moving the light away from the camera's visual axis. The phones with the shortest light to lens (LL) distance I have found to date are the iPhone 4 & the 4s, with only 6 mm between the axis of the lens and the light. All subsequent iterations of the iPhone have the light further away from the lens making direct phoneoscopy more challenging unless the pupil is fully dilated despite the advancements in camera technology in each new version. light to lens distance : alcatel pop4 10 mm iPhone4 6mm iphone 4s 6mm ipod touch 5 10 mm iphone 5s 9.25 mm iPhone 6 iphone 6s 9.5 mm iphone 6 plus 12 mm iPhone SE 9.25 mm iPhone 7 11.75mm iPhone 7plus 20mm (wide) & 11.5mm (tele) iPhone 8 12.5mm iPhone 8 plus 22.75mm (wide) & 12.5 mm (tele) iPhone X 6.5mm (wide) & 6.5 mm (tele) The winners : iPhone 4, 4S and X |
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Position of camera.
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For close direct phoneoscopy the lens needs to be as close to the corner of the phone as possible to allow the camera to be positioned at the optimal distance from the eye. This distance varies between cameras but is always close (<10mm).
All of the iphones with single rear cameras and all of the ipod touch generations have their camera lens positioned in the upper left corner of the phone making them ideal for positioning the phone camera. The camera position varies with other manufactures with many favouring a central position which makes using these phones for direct phoneoscopy more difficult. iPhone4 iphone 4s ipod touch 5 iphone 5s iPhone 6 iPhone 6 plus iphone 6s iphone 6 plus iPhone SE 8.25mm iPhone 7 8.5mm iPhone 7plus 8.75mm (wide) & 16.3mm (tele) iPhone 8 10.5 mm iPhone 8 plus 10.25mm (wide) & 19.5mm (tele) iPhone X 22.5mm (tele) & 11.5mm (wide) winners: 4, 4S and iPod touch |
Left to right: iPhone 4s, iPod touch 5th gen, iPhone 5s, iPhone 6s and the Alcatel Pop4. NB the central position of the alcatel's camera.
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Aperture & optical image stabilisation
Aperture determines the amount of light hitting the sensor. For phoneoscopy purposes this means the larger the aperture (the smaller the f number) the better. All iPhones from the 7 series onwards have a very helpful large aperture on their wide angle cameras of f1.8.
Large aperture means:
1) lower "shutter" speeds are needed so camera shake less of an issue
2) lower illumination intensity is needed to obtain good fundic images meaning fundoscopy is better tolerated in the conscious patient and the need for mydriasis is lessened.
3) depth of field is also reduced however this effect is rarely a negative influence on fundic photography as it is mitigated by the wide angle lens and we are, usually, imaging in a flat plane.
Optical image stabilisation(OIS) allows the camera to move within the camera body to dampen small movements of the phone meaning that camera shake cause less image blur. This allows lower camera "shutter" speeds to be used further increasing the light sensitivity of the camera. OIS was introduced on the iPhone 6plus camera.
Large aperture means:
1) lower "shutter" speeds are needed so camera shake less of an issue
2) lower illumination intensity is needed to obtain good fundic images meaning fundoscopy is better tolerated in the conscious patient and the need for mydriasis is lessened.
3) depth of field is also reduced however this effect is rarely a negative influence on fundic photography as it is mitigated by the wide angle lens and we are, usually, imaging in a flat plane.
Optical image stabilisation(OIS) allows the camera to move within the camera body to dampen small movements of the phone meaning that camera shake cause less image blur. This allows lower camera "shutter" speeds to be used further increasing the light sensitivity of the camera. OIS was introduced on the iPhone 6plus camera.
iPhone4 f2.8
iphone 4s f2.4
ipod touch 5 f 2.4
iphone 5s f2.2
iPhone 6 f2.2
iPhone 6 plus f2.2 & optical image stabilisation.
iphone 6s f2.2
iphone 6 plus f2.2 & optical image stabilisation.
iPhone SE f2.2
iPhone 7 f1.8 & optical image stabilisation.
iPhone 7plus f1.8 (wide angle lens) f2.8 telephoto lens & optical image stabilisation.
iPhone 8 f1.8 & optical image stabilisation.
iPhone 8 plus f1.8 (wide angle lens) f2.8 (telephoto lens) & optical image stabilisation.
iPhone X f1.8 (wide angle lens) f2.4 (telephoto lens) & optical image stabilisation.
The winners: iPhone 7 and up
iphone 4s f2.4
ipod touch 5 f 2.4
iphone 5s f2.2
iPhone 6 f2.2
iPhone 6 plus f2.2 & optical image stabilisation.
iphone 6s f2.2
iphone 6 plus f2.2 & optical image stabilisation.
iPhone SE f2.2
iPhone 7 f1.8 & optical image stabilisation.
iPhone 7plus f1.8 (wide angle lens) f2.8 telephoto lens & optical image stabilisation.
iPhone 8 f1.8 & optical image stabilisation.
iPhone 8 plus f1.8 (wide angle lens) f2.8 (telephoto lens) & optical image stabilisation.
iPhone X f1.8 (wide angle lens) f2.4 (telephoto lens) & optical image stabilisation.
The winners: iPhone 7 and up
Focal length equivalent (to 35mm camera)
iPhone4 28mm
iphone 4s 28mm
ipod touch 5
iphone 5s
iPhone 6
iPhone 6 plus
iphone 6s
iphone 6 plus
iPhone SE
iPhone 7
iPhone 7plus
iPhone 8
iPhone 8 plus 28mm (wide) & 56mm (tele)
iPhone X
iphone 4s 28mm
ipod touch 5
iphone 5s
iPhone 6
iPhone 6 plus
iphone 6s
iphone 6 plus
iPhone SE
iPhone 7
iPhone 7plus
iPhone 8
iPhone 8 plus 28mm (wide) & 56mm (tele)
iPhone X
Pixels & pixel resolution
iPhone4 5 Megapixel
iphone 4s 8 Megapixel (1.4 micron)
ipod touch 5 8 Megapixel
iphone 5s 8 Megapixel
iPhone 6 12 Megapixel
iphone 6s 12 Megapixel
iphone 6 plus 12 Megapixel
iPhone SE 12 Megapixel
iPhone 7 12 Megapixel
iPhone 7plus 12 Megapixel
iPhone 8 12 Megapixel
iPhone 8 plus 12 Megapixel
iPhone X 12 Megapixel
The winners: iPhone 6 and up
iphone 4s 8 Megapixel (1.4 micron)
ipod touch 5 8 Megapixel
iphone 5s 8 Megapixel
iPhone 6 12 Megapixel
iphone 6s 12 Megapixel
iphone 6 plus 12 Megapixel
iPhone SE 12 Megapixel
iPhone 7 12 Megapixel
iPhone 7plus 12 Megapixel
iPhone 8 12 Megapixel
iPhone 8 plus 12 Megapixel
iPhone X 12 Megapixel
The winners: iPhone 6 and up
Phone size
The optimal phone size will depend on a number of factors:
1) the size of your hands
Bigger phones can be tricky to hold close to the eye especially when you come to pressing the screen or the volume button to take an image.
2) the size of your thumbs
Smaller phones can make typing much more tricky - if you've big thumbs you're going to find entering text and altering camera settings more difficult.
3) your eye sight:
Sorry guys but past 40 (gosh that sounds young now!) you're going to have to accept that presbyopia is on it's way, the bigger the display the easier this will make your transition in to middle age.
4) the size of your patient:
The equine eye is very forgiving and even the largest iPhone is easy to use to obtain direct retinal images however with small animal patients the smaller the phone the better, currently this makes the iPhone SE the best option for small animals.
I currently use the iPhone 7plus - the screen size is amazing (especially as I am now past 40) but I do need some digital gymnastics to hold the phone and obtain an image. Fpr our clinicians I've given them the iPhone SE as this is the most versatile of the modern iPhones.
1) the size of your hands
Bigger phones can be tricky to hold close to the eye especially when you come to pressing the screen or the volume button to take an image.
2) the size of your thumbs
Smaller phones can make typing much more tricky - if you've big thumbs you're going to find entering text and altering camera settings more difficult.
3) your eye sight:
Sorry guys but past 40 (gosh that sounds young now!) you're going to have to accept that presbyopia is on it's way, the bigger the display the easier this will make your transition in to middle age.
4) the size of your patient:
The equine eye is very forgiving and even the largest iPhone is easy to use to obtain direct retinal images however with small animal patients the smaller the phone the better, currently this makes the iPhone SE the best option for small animals.
I currently use the iPhone 7plus - the screen size is amazing (especially as I am now past 40) but I do need some digital gymnastics to hold the phone and obtain an image. Fpr our clinicians I've given them the iPhone SE as this is the most versatile of the modern iPhones.
iPhone camera specs:
iPod touch (5th gen)
Camera
- 8MP camera
- Autofocus
- ƒ/2.4 aperture
- Five-element lens
- Hybrid IR filter
- Backside illumination
- Auto image stabilisation
- Auto HDR for Photos
- Improved face detection
- Exposure control
- Panorama (up to 43MP)
- Burst mode
- Tap to focus
- Photo geotagging over Wi-Fi
- Timer mode
- 1080p HD video recording (30 fps)
- Tap to focus while recording
- Slo-mo video (120 fps)
- Time-lapse video
- Cinematic video stabilisation
- Improved face detection
- 3x zoom
- Video geotagging over Wi-Fi
iPhone 4
Camera, photos, and video
28mm equivalent focal length
https://arstechnica.com/gadgets/2010/06/sizing-up-the-iphone-4-for-shutterbugs/
- Video recording, HD (720p) up to 30 frames per second with audio
- 5-megapixel still camera
- VGA-quality photos and video at up to 30 frames per second with the front camera
- Tap to focus video or still images
- LED flash
- Photo and video geotagging
28mm equivalent focal length
https://arstechnica.com/gadgets/2010/06/sizing-up-the-iphone-4-for-shutterbugs/
iPhone 4s
Camera, Photos, and Video
- 8-megapixel camera
- Autofocus
- Tap to focus
- Face detection in still images
- LED flash
- Video recording, HD (1080p) up to 30 frames per second with audio
- Video stabilization
- Front camera with VGA-quality photos and video at up to 30 frames per second
- Photo and video geotagging
iPhone 5
iPhone 5s
iSight Camera
- 8 megapixels with 1.5µ pixels
- ƒ/2.2 aperture
- Sapphire crystal lens cover
- True Tone flash
- Backside illumination sensor
- Five-element lens
- Hybrid IR filter
- Autofocus
- Tap to focus
- Exposure control
- Auto HDR for photos
- Face detection
- Panorama
- Auto image stabilization
- Burst mode
- Photo geotagging
- 1080p HD video recording (30 fps)
- True Tone flash
- Slo-mo video (120 fps)
- Time-lapse video
- Video stabilization
- Take still photos while recording video
- Face detection
- 3x zoom
- Video geotagging
iPhone SE
Camera
Video Recording
- 12‑megapixel camera
- ƒ/2.2 aperture
- Five-element lens
- 5x digital zoom
- Live Photos with stabilisation
- Local tone mapping
- Face detection
- True Tone flash
- Sapphire crystal lens cover
- Backside illumination sensor
- Hybrid IR filter
- Autofocus with Focus Pixels
- Tap to focus with Focus Pixels
- Exposure control
- Noise reduction
- Auto HDR for photos
- Panorama (up to 63 megapixels)
- Auto image stabilisation
- Burst mode
- Timer mode
- Photo geotagging
Video Recording
- 4K video recording at 30 fps
- 1080p HD video recording at 30 fps or 60 fps
- 720p HD video recording at 30 fps
- 3x digital zoom
- True Tone flash
- Cinematic video stabilisation (1080p and 720p)
- Continuous autofocus video
- Face detection
- Noise reduction
- Slo‑mo video support for 1080p at 120 fps and 720p at 240 fps
- Time‑lapse video with stabilisation
- Take 8-megapixel still photos while recording 4K video
- Playback zoom
- Video geotagging
iPhone 6 & 6 plus
iSight Camera
- 8-megapixel iSight camera with 1.5µ pixels
- Autofocus with Focus Pixels
- ƒ/2.2 aperture
- Optical image stabilization (iPhone 6 Plus only)
- True Tone flash
- Five-element lens
- Hybrid IR filter
- Backside illumination sensor
- Sapphire crystal lens cover
- Auto image stabilization
- Auto HDR for photos
- Face detection
- Exposure control
- Panorama (up to 43 megapixels)
- Burst mode
- Tap to focus
- Photo geotagging
- Timer mode
- 1080p HD video recording (30 fps or 60 fps)
- True Tone flash
- Slo-mo video (120 fps or 240 fps)
- Time-lapse video with stabilization
- Cinematic video stabilization
- Continuous autofocus video
- Take still photos while recording video
- Improved face detection
- 3x zoom
- Video geotagging
iPhone 6s & iPhone 6s Plus
iPhone 6s & iPhone 6s Plus
- 12-megapixel camera
- Live Photos with stabilization
- Autofocus with Focus Pixels
- Optical image stabilization (iPhone 6s Plus only)
- True Tone flash
- Panorama (up to 63 megapixels)
- Auto HDR for photos
- Exposure control
- Burst mode
- Timer mode
- ƒ/2.2 aperture
- Five-element lens
- 5x digital zoom
- Hybrid IR filter
- Backside illumination sensor
- Sapphire crystal lens cover
- Auto image stabilization
- Local tone mapping
- Noise reduction
- Face detection
- Photo geotagging
- 4K video recording at 30 fps
- 1080p HD video recording at 30 fps or 60 fps
- 720p HD video recording at 30 fps
- Optical image stabilization for video (iPhone 6s Plus only)
- True Tone flash
- Slo-mo video support for 1080p at 120 fps and 720p at 240 fps
- Time-lapse video with stabilization
- Cinematic video stabilization (1080p and 720p)
- Continuous autofocus video
- Noise reduction
- Take 8-megapixel still photos while recording 4K video
- Playback zoom
- 3x digital zoom
- Face detection
- Video geotagging
iPhone 7 & iPhone 7 Plus
iPhone 7
iPhone 7 Plus
- 12mp camera
- f/1.8 aperture
- Digital zoom up 5x
iPhone 7 Plus
- 12MP wide-angle and telephoto cameras
- Wide-angle: f/1.8 aperture
- Telephoto: f/2.8 aperture
- Optical zoom at 2x, digital zoom up to 10x
- Optical image stabilization
- Six‑element lens
- Quad-LED True Tone flash
- Panorama (up to 63 megapixels)
- Sapphire crystal lens cover
- Backside illumination sensor
- Hybrid IR filter
- Autofocus with Focus Pixels
- Tap to focus with Focus Pixels
- Live Photos with stabilization
- Wide color capture for photos and Live Photos
- Improved local tone mapping
- Body and face detection
- Exposure control
- Noise reduction
- Auto HDR for photos
- Auto image stabilization
- Burst mode
- Timer mode
- Photo geotagging
https://newatlas.com/every-iphone-specs-comparison/
iPhone 8 & 8 plus
Camera
Wide-angle: ƒ/1.8 aperture
Telephoto: ƒ/2.8 aperture
Optical zoom; digital zoom up to 10x
--
Portrait mode
--
Portrait Lighting (beta)
Both models:
Video Recording
- 12MP camera
- 12MP wide-angle and telephoto cameras
- ƒ/1.8 aperture
Wide-angle: ƒ/1.8 aperture
Telephoto: ƒ/2.8 aperture
- Digital zoom up to 5x
Optical zoom; digital zoom up to 10x
--
Portrait mode
--
Portrait Lighting (beta)
Both models:
- Optical image stabilisation
- Six-element lens
- Quad-LED True Tone flash with slow sync
- Panorama (up to 63MP)
- Sapphire crystal lens cover
- Backside illumination sensor
- Hybrid IR filter
- Autofocus with Focus Pixels
- Tap to focus with Focus Pixels
- Live Photos with stabilisation
- Wide colour capture for photos and Live Photos
- Improved local tone mapping
- Body and face detection
- Exposure control
- Noise reduction
- Auto HDR for photos
- Auto image stabilisation
- Burst mode
- Timer mode
- Photo geotagging
- Image formats captured: HEIF and JPEG
Video Recording
- 4K video recording at 24 fps, 30 fps or 60 fps
- 1080p HD video recording at 30 fps or 60 fps
- 720p HD video recording at 30 fps
- Optical image stabilisation for video
- Optical zoom; 6x digital zoom (iPhone 8 Plus only)
- Quad-LED True Tone flash
- Slo‑mo video support for 1080p at 120 fps or 240 fps
- Time‑lapse video with stabilisation
- Cinematic video stabilisation (1080p and 720p)
- Continuous autofocus video
- Body and face detection
- Noise reduction
- Take 8MP still photos while recording 4K video
- Playback zoom
- Video geotagging
- Video formats recorded: HEVC and H.264
iPhone X
Camera
Video Recording
- 12MP wide-angle and telephoto cameras
- Wide-angle: ƒ/1.8 aperture
- Telephoto: ƒ/2.4 aperture
- Optical zoom; digital zoom up to 10x
- Portrait mode
- Portrait Lighting (beta)
- Dual optical image stabilisation
- Six-element lens
- Quad-LED True Tone flash with slow sync
- Panorama (up to 63MP)
- Sapphire crystal lens cover
- Backside illumination sensor
- Hybrid IR filter
- Autofocus with Focus Pixels
- Tap to focus with Focus Pixels
- Live Photos with stabilisation
- Wide colour capture for photos and Live Photos
- Improved local tone mapping
- Body and face detection
- Exposure control
- Noise reduction
- Auto HDR for photos
- Auto image stabilisation
- Burst mode
- Timer mode
- Photo geotagging
- Image formats captured: HEIF and JPEG
Video Recording
- 4K video recording at 24 fps, 30 fps or 60 fps
- 1080p HD video recording at 30 fps or 60 fps
- 720p HD video recording at 30 fps
- Optical image stabilisation for video
- Optical zoom; 6x digital zoom
- Quad-LED True Tone flash
- Slo‑mo video support for 1080p at 120 fps or 240 fps
- Time‑lapse video with stabilisation
- Cinematic video stabilisation (1080p and 720p)
- Continuous autofocus video
- Body and face detection
- Noise reduction
- Take 8MP still photos while recording 4K video
- Playback zoom
- Video geotagging
- Video formats recorded: HEVC and H.264