Cameras and Lenses




Cameras and Lenses

I have an obsolete or rare camera. Will Photo Transit support it?

Yes. Essentially, any camera can be set up within the app. You will need to know the size of the sensor or film type that the camera uses, measured in millimeters.

In the app, bring up the Camera popover, tap ‘+’, add a name for your camera, then tap the detail disclosure button to the right of the ‘Sensor’ cell. You can either scroll to view the standard camera types, or type in the search field to find the type you need.

If your camera type is not shown in the list, tap ‘+’ and you can add your own custom camera type.

Alternatively, email us and let us know what camera type you would like to add and we'll look into including it in the update list. You can check for and download updated sensor/film types under Settings (top right).

Can I use a non-interchangeable lens camera with Photo Transit?

Yes. However, at present, there’s a little more work to set it up.

The app currently expects lenses to be separate from cameras. Add your camera first. You may well need to add a custom camera type (such as for compact cameras), which means you’ll need to look up the sensor dimensions for your camera. These can normally be obtained from the manufacturer’s web-site under the technical specifications page.

Once you have the camera setup, you will need to add the lens. Depending on the camera, this will either be a prime (fixed focal length) or a zoom (variable focal length) lens – typically, it will be a zoom.

This should be the only lens you should add for the camera. After all – the lens is not interchangeable, right?

We plan to add built-in support for non-interchangeable lens cameras soon.

What about macro lenses?

Because of their higher magnification factor, the standard formula for calculating field of view does not apply as well to macro lenses.

Photo Transit 1.0 does not correct for the magnification factor of macro lenses. As the app is relatively unsuited to short-range photography (i.e. the situations in which macros lenses are typically used), we suspect this is not such a big issue.

However, we expect to add this support in a future version.

I shoot with film. Can I plan shots using the app?

Yes. Photo Transit ships with built-in support for the following film types:

  • 35mm
  • 6 × 4.5cm
  • 6 × 6cm
  • 6 × 7cm
  • 6 × 9cm
  • 6 × 12cm
  • 6 × 17cm
  • 4” × 5”
  • 8” × 10”

You can add any other film type you may need manually. Alternatively, email us with details so that we may update the camera type list. (You can check for updated sensor/film types from within the app, under Settings.)


Can I make a shot list?

Yes. You can create as many Projects as you like, and add shots to each project.

Edit the shots in your project to put them in any sequence you want. In addition to all the basic camera, lens and position data, each shot can include a reference URL (e.g. a link to a web-site with additional relevant information), a reference shot chosen from the Camera Roll on your device, and a freeform notes field.

For details on sharing and exporting your shot list, see Sharing on this page.

What does the elevation panel tell me?

Photo Transit includes some sophisticated elevation planning information to help you virtually scout sight-lines and understand the vertical field of view for your shot.

When the elevation panel is closed, you will see the elevation above sea level for both camera and subject locations. In addition to showing the range (distance) from camera to subject, and bearing (measured in degrees), the app shows the altitude from camera to subject.

Altitude is the apparent angle measured vertically – that is, if you’d need to tilt the camera up to see the subject, then you'll see a positive angle, and if you’d need to tilt down, then you’ll see a negative angle. The altitudes shown in the app are all adjusted for the curvature of the earth. This is an important factor over longer distances (as anyone who has stared at the far horizon will know).

Apparent means that the altitude has been adjusted for the effects of atmospheric refraction. Over longer distances this has the effect of ‘lifting’ objects above the horizon (which is why we see sunrise earlier than we would if there were no atmosphere on Earth).

Correction for curvature of the earth and for atmospheric refraction are two reasons the data from Photo Transit is better than what you would get from simple high school trigonometry (i.e. elevation over distance, assuming a flat, airless Earth).

Vertical Field of View Chart

The vertical field of view chart line, which is displayed on the left hand axis of the chart, shows you two things:

  1. The apparent altitude along the line from camera to subject, from the photographer’s perspective
  2. The vertical field of view for the current camera/orientation/pitch/height/lens/focal length combination (shown as two turquoise overlays on the chart – the visible area is between these two overlays)

Both are measured in degrees (°). Double tapping on the chart toggles between zooming in to cover the apparent altitude profile, or zooming to cover both apparent altitude profile and vertical field of view.

Changing any of the factors affecting the camera vertical field of view will adjust the FOV overlays on the chart.

Elevation Profile Chart

The second data set shown on the chart (optionally – you can toggle one or the other off using the chart legend buttons), is a simple elevation profile showing height above sea level along the line from camera to subject. You can toggle one or the other off using the chart legend buttons.

It is instructive to compare the apparent altitude line with the elevation profile for a hilly or mountainous area you are familiar with. You’ll see that hills close to the camera loom larger in size than more distant peaks. This reflects what the camera will see in real life: if you stand close to the foothills, it’s often impossible to see the mountain peaks behind.

Dashed vs. Solid Lines

The chart lines indicate visibility along the line from camera to subject: areas that cannot be seen by the camera are shown as dashed lines. Areas that are visible are shown as solid lines.

Subject Height Above the Ground

If you specify a subject height above the ground (e.g. the height of a prominent building), then a dashed or solid line is shown at the right hand side of the chart representing the subject above the ground. If the subject is wholly or partially obscured by intervening terrain, then that portion of the subject line is shown as dashed.

Which elevation data source should I use?

Photo Transit provides access to three different elevation data sources:

  • Google Elevation
  • SRTM3 (the Shuttle Radar Topography Mission)
  • AsterGDEM (Aster Global Digital Elevation Model)

Each has different characteristics, so here are some guidelines:

  • Google Elevation: best for cities, accurate mountain summits elevations, and short camera to subject distances; data points are interpolated (smoothed); data includes bathymetry (depth data for undersea locations); data cannot be stored offline
  • SRTM3: high quality data elevation model for coverage between latitudes 60°N and 56°S; 3 arc-second resolution, not interpolated; viewed data is stored for offline use
  • AsterGDEM: a newer data elevation model for coverage between latitudes 83°N and 65°S; 3 arc-second resolution, not interpolated; viewed data is stored for offline use

For SRTM3 and AsterGDEM, if data is unavailable from the primary source, the secondary source is automatically queried.

For shots planned over water (e.g. lakes, ocean), you may wish to use SRTM3 or AsterGDEM: Google Elevation includes depth data which is misleading for visualizing the field of view or subject height above the ground.

Can I use the app offline?

Yes. Photo Transit provides options for both offline maps and elevation data. The following offline map types are included:

  • Open Street Map, with tiles provided by Carto
  • Open Cycle Map topographic, provided by Thunder Forest

The following elevation data sources support offline use:

  • SRTM3
  • AsterGDEM

For both maps and elevation, data is available offline for up to 1 year from the time of first download. Offline storage is automatic upon access to the data. That means you must view the data you need while connected to the internet, using one of the supported offline map types or data sources. When you subsequently view the data while offline, the map tiles and data are loaded from your local offline store.

Other map and elevation data sources may be available when offline if you have viewed the required data recently, but this should be not relied on.

You can clear all offline data stored by the app from the Settings page.

How can I use Street View?

Google Street View™ provides street level 360° imagery for many road networks in countries around the world.

If you position your camera near a street for which Street View imagery is available, you can use Photo Transit as a virtual Street View camera controller, zooming in or out and adjusting the pitch up and down. The initial direction of the Street View camera is set to point to the subject position for your shot.

The field of view of the Street View camera is set to match the horizontal field of view of your camera/lens setup, as far as possible. (Please note, this is field of view is an approximation, not a precise match – however, we think it’s a useful one.)

You can use the Street View imagery to get a sense of your shot composition. In addition, you can use the built-in Street View controls to adjust your shot setup: zooming in or out directly on Street View will adjust the selected focal length of your camera, up to the limits of the selected variable zoom lens. Panning to adjust the direction of view will move your subject pin, but maintain the previous camera-subject range. Tilting the Street View camera up and down will adjust your camera pitch setting. Advancing the Street View camera down a road will move your camera pin to the new Street View car coordinates.

Note: the Street View camera is generally positioned around 2m or 7-8 ft above the ground. Changing the camera height in Photo Transit won't affect this.


What is a ‘Transit’?

A transit is short name for a ‘transit-compass’, defined by the Oxford English Dictionary as ‘an instrument, resembling a theodolite, used in surveying for the measurement of horizontal angles.’

The Photographer's Transit is a digital transit-compass, used to help photographers visualize the field of view for planned shots.

What do you mean by a 'Shot'?

In Photo Transit, a Shot is a way of saving the state of the app to record the key details you need to recreate a photo.

Each Shot includes the following information:

  • A name for the shot
  • Camera coordinates (latitude/longitude)
  • Camera type/name
  • Lens selection and focal length (if using a variable zoom lens)
  • Camera orientation (landscape/portrait)
  • Pitch (the amount of tilt up/down, measured in degrees)
  • Height above the ground
  • Subject coordinates (latitude/longitude)
  • Subject height above ground (for example, the height of a building)
  • Map view details (zoom level, map center coordinates)

Optionally, you can include a reference URL, a reference photo and freeform text notes.

So, a ‘shot’ isn't the actual photo – it's the plan of how to make the photo.

What version of iOS does the app require?

Our policy is to support the current major version of iOS and its predecessor, but only while the previous version represents more than 5% of monthly active users. We may drop support for minor versions where significant bugs exist. (For example, iOS 8.0 had a major bug related to font display, which is why our next release will require iOS 8.1 or higher.)


How can I share my shots with others?

You can post your shot to Twitter or Facebook, or send it via iMessage/SMS. The message or post contains a sharing link to a public web-site where users can view your shot plan. They don’t need to be running the app to view this.

In addition, you can email your shot or project (a shot list) to friends and colleagues. The email includes full shot information, links to the sharing web site, links to open the shot back in Photo Transit or TPE (The Photographer's Ephemeris), plus a KML export that can be opened in Google Earth™ or your favorite GPS app.

What can I do with the Project or Shot KML file?

When you email your project or shot, the email contains the data in KML format.

KML (Keyhole Markup Language) is a standard data format used by programs such as Google Earth™ and various GPS apps to exchange geographic information.

You can open the KML export in Google Earth on your desktop computer, or even on other iOS or Android devices. (The Desktop version of Google Earth offers the best KML support, however.)

If you export a project, then your shot list will appear as a folder within Google Earth. Each shot is included as a sub-folder. Click on the folder to view the full shot details (similar to the data included in the email itself). Double click on the camera within the folder to fly to a viewpoint above the camera, looking towards your subject.

You can also open the KML file in your favorite mobile GPS app, for example, Gaia GPS, so you can be guided to your shooting location.

Are my shot lists private?

Generally yes, unless you choose to share them via Social networking, or add a shot to your Calendar.

When you email a shot or a project, the email contains one or more links to our sharing site, share.phototransit.com. However, that link is only included in your email, so access to it is under your control.

If you share a shot via Facebook, Twitter or other social networking sites, or add it to your Calendar via the app, then we will generate a shortened version of the URL. Your Shot URL is sent to a 3rd party link shortening service to obtain the shortened URL and will be included in the list of shortened links under our account.

Additionally, if you or anyone with whom you share either the long or short form of the link clicks that link, the URL will be recorded in the web logs and analytics for our website.

Otherwise, at this time, your shots are not uploaded by the app to any other database or location.

For details on how we handle your data, please refer to our privacy policy.