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After more than a year of effort, we finally released the first version of the PlanIt! for Photographers on iOS.!-for-photographers/id898876435 (iOS version, for iPhone, iPad and iPod touch) (Android version)

Just so you know, we are also migrating to this blog to and also are building up a new site for this app (not done yet). We will keep this blog updated as well during the transition.

Here are some screenshots on iPhone 6 plus. There is a user guide at

IMG_1093 IMG_1089 IMG_1091 IMG_1092 IMG_1096IMG_1090



Joerg, a passionate photographer and blogger from Sensorgrahy, was kindly enough to provide his review of the PlanIt! for Photographer.

What making me feel excited the most is when he said “PlanIt! takes you beyond the capabilities of TPE.” As we all knew, TPE is a great (probably the first) app to provide the ephemeris information in an app, which was also the app that inspired me to add the ephemeris feature to the PlanIt. But our goal is this app is way more than what TPE can do.  As he already pointed out, being able to preview the Sun/Moon/Star/MilkyWay position using the VR mode is a great addition. Not to mention the simulation of the timelapse and the startrail feature. 

BTW, Joerg also helps us to translate the app into Germany after he saw some translations were not accurate (as they were not translated by a real photographer). Thanks. We will have a new release soon to include his translation. 

After two months of hard work and beta testing among our beta users, we are glad to announce the release of the PlanIt! Let me start by saying thank you to our beta users. You provide many valuable feedback  and bug reports. Without you, the new release would be impossible.

App Name Change

First thing first so that you don’t get confused. The app was called Photographer’s Field Tools (PFT). We plan to introduce several apps in the photographer’s tools category, so we decided to rename it to PlanIt!. It stands for “Plan the shot”. It is the same app as the old PFT. If you purchased PFT Pro before, it is free for you to upgrade. If you downloaded PFT free version and purchased the in-app purchases, you will get the upgrade for free too.

Promo - Mt.Shasta

Features in 3.0

1. Viewfinder mode. Under the background selection action, we added three more entries – Viewfinder (VR), Viewfinder (AR) and Viewfinder (Picture). With these features, you can visualize the scene in a simulated viewfinder. We will draw the ground contour, or you can use your phone’s camera to preview the scene, or you can select an existing picture as the viewfinder background. We will render celestial objects on the viewfinder so that you can compose the scene visually.

2. Milky Way. We added an Ephemeris page for the Milky Way. I am telling you now – finding the milky way is never so easy.

3. Star-trail and time-lapse simulation. You can actually “Play” the viewfinder to simulate what happen as time goes by. It will show you the whole star-trail or the time-lapse  process, from start to end. For time-lapse, you can even set the camera’s facing azimuth and tilting angle for the start and the end of the time-lapse.

4. Finding Sun or Moon? Just using your finger to circle an area on the viewfinder, we will show you the list of dates/times where the Sun or the Moon will appear there.

5. Many more options are added to the settings screen.

6. Markers can defined and saved. You can even define the height/width of the marker so that you can use marker to represent a high building and show it in the viewfinder.

7. The plan and markers can be saved as files. You can share the plan file or the marker file to your friend using a social app. Your friend, if he/she also has PlanIt, can open the file right from the social app.

8. And many small features.


User Guide

PlanIt! User Guide (Android)

I know people are busy and never read manual. In this case, I strongly suggest you read through the user guide at least once if you are serious about photographing. We are also very active on email. If you have any questions about how to do certain things, feel free to send us an email.



We just had a new beta release for PlanIt! The main enhancement in this beta release is to bring different modes to the viewfinder. In the previous beta release, we used the elevation service to draw the ground contour. While it works, the display is not very attractive. In this release, we improved it using two approachs – use the phone camera to create an augmented reality, and use an existing picture to replace the ground contour. We called the existing ground contour mode – the ViewFinder (VR) mode, the camera AR – ViewFinder (AR) mode, and the picture one – ViewFinder (Picture) mode. All three modes can be selected by clicking on the map icons on the action bar.

Take a look at the three pictures below. You can see the camera location and the scene location in case you would like to try it yourself. I also attached the jpg file I used in this example as well as the .xmd file which is the metadata file used by PlanIt! along with the picture.


The left one is the ViewFinder (VR) mode. As you can see, it shows a contour of the Half Dome but without any other details. The right one is the ViewFinder (Picture) mode. Because it is a real photo, you can see exactly what it would look like at this particular location. Most importantly, you can adjust the time to see the position of celestial objects in the future or in the past using this real photo as background.

device-2014-05-12-200603  device-2014-05-12-200556


If you are at the location, you can also turn on the phone camera to take a picture or use the augmented reality.

You can download the Half Dome photo I used in this post below. The corresponding data associated with this photo is also included below. I strongly encourage you give your own photo a try. Even with the same scene, you can compose it with Sun, Moon, star-trails, or milky way, and to give it a different feeling.

Picture file used by in this post

You also need a .xmd file. Just copy the text below and save it at the same folder as the picture file using the same file name except with “.xmd” at the end. If you save the picture file above as “pic1.jpg”, then save this xml file as “pic1.jpg.xmd”.

“Azimuth”: 84.78215026855469,
“VerticalAngleOfView”: 59.599998474121094,
“HorizontalAngleOfView”: 41.794071197509766,
“Latitude”: 37.74017171039168,
“Longitude”: -119.59974355995654,
“Elevation”: -2.2449021339416504



I never thought I will be doing this but after I finished the implementation the viewfinder feature in the Planit app, it occurred to me. Why not try to date the famous Moon and Half Dome photo using this app?

Here is the original photo by Ansel Adams.


Let’s list the clues we had so far.

  1. Waxing Gibbous moon as we can see.
  2. There was snow on the ground which means it was in winter.
  3. We also know the photo were taken in 1960 and were taken after 3pm in the afternoon as Ansel said it in his Autobioyaphy. But he never mentioned the exact date and the exact time.
  4. The camera location is hard to be exact so we have to try our luck here.  The shadow on the left is the Washington Column. With that in mind, I put the camera at the below location so that the Washington Column is between the camera and the Half Dome.

After studying the map and the picture carefully, see below for where i place the camera icon and the scene icon. You can see the GPS coordinates of both locations below. I verified the camera location is at an open area to the west of the Ahwahnee Hotel so it is possible to get there and have a clear view to the half dome as I’ve been there before. On the screenshot below, the line between the two icons is green which also means there is nothing in between.

device-2014-04-19-224416 device-2014-04-19-222114

Now switch to Finder page, select Waxing Gibbous, select the date to be 1/1/1960 to 12/31/1960.  Now switch to the viewfinder view. The main advantage of Viewfinder view is you can drag the area on the viewfinder to define where to search. The area you drag will be concerted to the elevation angle (or altitude) and the azimuth. The altitude is fixed but the azimuth is a range. You can also drag the corresponding icon on the side to fine tune the values. The contour of the Half Dome really helps to determine the Moon location.

With just a few drags and clicks, I got the following three dates back. As you can see, only the last one meets all the conditions (winter, after 3pm).


Believe it or not, we just dated the famous photo. It was taken on December 28, 1960 around 4pm. The Moon is an 86.1% Waxing Gibbous. It would take hours of calculations but with this app, it is just a few minutes.

Since now I knew the moon position on the original photo, it is really easy for this app find all the date/time that match closely to the original photo. I just need to change the date range!

I googled a little bit and found in 11/28/2009, they predicted the Moon at the almost exact same location. They called it Moon and Half Dome Celestial Encore. You can find a link below.


Here is what this app shows on 11/28/2009. Unfortunately, no photo came out from that encore because there was cloud.

Of course, everyone would be more interested in when the next time would be in the future. So I set the starting date as today and the ending date to be five years later. Here is what I got for the next five years.


The best matching one is 12/29/2017. Sun and Moon position, time of the day are almost exactly the same as Ansel Adams’s Moon and Half Dome. If you would like to replicate the classic, that’s the time you should be at Yosemite.

Here is a quick comparison of 1960, 2009 and 2017. As you can see, the 2017 one is actually more accurate than the 2009 one in all aspects.

Date Time Moon Percentage Moon Azimuth Moon Altitude
(Original Photo)
16:05 86.1% 89.0 21.8
(Celestial Encore)
15:54 88.7% 88.7 21.8
16:06 86.3% 88.8 21.8



There is a full moon eclipse coming soon. You can find the exact date and time at Since I am in California, the actual starting time would be Apr 14 at 9:55 PM and Apr 15 at 3:36 AM. I really want to pre-visualize the whole process using the PlanIt! beta release which is the next release of the original PFT app.

Based on the calculation of PlanIt!, the moon starts at azimuth: 130°, elevation: 27° and ends at azimuth: 225°, elevation: 30°. Basically, from the southeast to the southwest for almost 95° rotation. If you want to use one lens to cover the whole process without using a motion control device, you need at least 16mm on a full frame camera which has a horizontal angle of view of 96.7°. If you have a 14mm, use it as 16mm will be almost from edge to edge.

Sounds simple but it is hard to visualize the numbers. Viewfinder is here to help. Please check out the video below where I simulate the whole moon eclipse using the time-lapse feature in PlanIt!.

In this video, I used the Half Dome as the background. I set the camera location at a location at the Snow Creek Trail. At this location, the Half Dome will be on the south.

The camera location (click for a larger image):


Moon position when eclipse starts:

device-2014-04-13-100808  device-2014-04-13-102315

Moon position when eclipse ends:

device-2014-04-13-100834  device-2014-04-13-102331

If you happen to be at Yosemite National Park, you can give it a try. Plan to camp at the Snow Creek Trail 🙂

If you are in other area of the world, you can find some other local landmarks to use it as the foreground of the whole moon eclipse – skyline, mountain peaks, lakes etc. The PlanIt! will definitely help you  to plan the shots accordingly. You could make a time-lapse of it. Or you can merge the photos at every 10 minutes or so using lightening mask into one photo.

Have fun!

We are working hard for our next release of the Photographer’s Field Tools. We decided to rename it to PlanIt! because we will introduce several apps in this Photographer’s Tools Series. The PlanIt! is the first app in this series. We have three more apps in the pipe line.

We also have a Google+ beta tester community opened. If you are existing Photographer’s Field Tools users who purchased the Pro version or purchased the in-app purchase of the Ephemeris features in the free version, we can invite you to join this community so that you get access to the beta releases.

You can find an updated tutorial which includes the new features.

PlanIt! Ephemeris Features (next release)

Here are a few screenshots of the new features. We called it the Viewfinder.

1. The view from the Glacier Point to the Half Dome. It is in a panorama. The Milky Way runs over the Half Dome at about 11pm and there is no moon. It will be a perfect night to capture the magnificent starry Glacier Point view.



The same view except the phone is rotated to landscape orientation so that you can see the viewfinder in a larger view.



2. To date the famous Ansel Adams’s Moon and Half Dome. You can find details in the attached pdf file. This screenshot below shows you another perfect date in 2017 that is almost the same as 12/28/1960 when Ansel took his legendary photo.



3. The time-lapse settings. Now you can set a different azimuth, elevation angle and focal length for the starting and ending times and we will visually show the whole time-lapse process to you in the viewfinder.


4. Simulate the star-trails. All the stars are at their real positions at the giving time.




The user interface of the Photographer’s Field Tool has been updated for a while but we haven’t released updated help document to go with it. Sorry for the late action. You can find two documents for it.

Photographer’s Field Tools – Introduction (For Android)

Photographer’s Field Tools – Ephemeris (for Android)

Both documents are for the Android version. Just so you know, if you ave an iOS user, you can expect to see an iOS version of Photographer’s Field Tools in April 2014. You will also see some great new features to the existing app on the Android version as well. Stay tune!

I am really excited to announce that we just had a new release on Photographer Field Tools (Pro) where we added the ephemeris features. Great photos depend on the great light which usually come from the Sun and Moon. The ephemeris features will allow you to find the Sun and Moon position at any given time and location so that you can plan your trip accordingly, previsualize the scene with Sun/Moon in the composition. It even allows you to find the exact date and time where Sun or Moon or both appear at the exact position on the sky.

In the picture below, I am looking for the Moonrise behind the Half Dome. The camera was pinned at the Tunnel View. The scene location was pined at the peak of the Half Dome. The elevation tells me the viewing angle from Tunnel View to the peak of the Half Dome is 5.9° and azimuth of 75.9°. Using those two angles, the app will find the date and time where a full moon will appear at the location with +/- 5°. You can then review each time to find where the exact location of Sun and Moon. As the screenshot below shows, at Feb 13, 2014, the Sunset and Moonrise will happen at the same time. You will see the Half Dome glowing in the Sunset color and a full moon will rise above the Half Dome slightly to the right of its peak. I will certainly go there on that day to take such a picture 🙂

tunnel view - half dome - moonrise - sunset

Since the above event is a thing in the future, I decided to find an existing photo in the past and simulate what was happening on that time using PFT. After some search, I found a photo by Willie Huang at where he was generous enough to share all the EXIF info which helps me to know the date/time was Dec 27, 2012 5:27 PM. He took it at 50mm focal length. He also described what happened on that evening. He said the Sun was down already when Moon came out. The Moon came out behind the Cloud Rest (which I marked it on the screenshot below). As you can see, the moonrise line (the purple line) points at it exactly. By the time Willie took this picture, the moon is at 9.5°. The sun is at 8.0° below horizon already (which is still at nautical twilight). If there was still sunset orange light on the Half Dome, it would be even better.

tunnel view moonrise 2012  willie huang

tunnel view

(Courtesy of Willie Huang,

I live in the beautiful San Diego. There is a pier called Scripps Pier. It is very long, straight pier that points to the ocean. On two days of every year, you will see a flock of photographers gathered under the pier. The reason is the sun will set just below the pier. The pier is pretty long so the viewing angle is less than 1 degree. By using the ephemeris feature, I can easily find out the two days May 1, 2014 7:31 PM and Aug 10, 2014 7:39 PM. One day before the two dates should also be good because it means the Sun will be slightly above the sealevel when centered under the pier. See you there! 

scripps pier

I had verified the result with dates in the past. You can google “Scripps Pier Sunset” to find photos taken in the past. Here is one of the dates in 2012.

In a real camera, we have grid lines in the viewfinder and the LCD to help us composing the scene, usually 3×3 grid with diagonal lines for certain cameras.  In the Lightroom, there are more choices for the grid lines in the crop tool –  1/3, golden ratio, spiral, etc. I think it would be great that PFT can has such a grid line too for the focal length tools because I often find that I have to look at the above/below angle values and do calculation in my mind. Would it be easier if the grid line will show me the exact composition I want? Here you go. So far, we added 1/3, 1/4, 1/6 and golden ratio four grid lines. Here is an example of Mt. Shasta with 1/3 grid lines because I want the sky/mountain takes 1/3 of the scene, the reflection and lake takes the other 2/3. I can make sure this composition just by looking at the grid lines.

Mt Shasta - Vertical - Grid Lines

It also works for horizontal focal length tool. For example, in the composition below, I can easily make sure the half dome takes 1/3 of the scene.

Half Dome - Focal Length - Grid Lines


Is it real? Yes. You can see the shot I took below which is at 32mm as PFT said.

8-8-2013 8-28-32 AM