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Mixed results with X5 and 17mm & 25mm lenses

Today was my first outing with the new app and the X5.

Had mixed results, which I will outline and see some good things and some shortcomings with the feature set for the X5 currently.

First off, 17mm 1.2 hect site, 80 metres for 1.2cm resolution, battery limit at 10 mins (around freezing temps so safe limits applied).  Message onscreen correctly identifying 17mm lens and one to state ensure lens is set to AF which it was.

Exposure to set to auto just to try and with motion blur regulating speed, f2 @1/250 was selected.   

The resulting photomosaic stitched locally was ok, but I know the lens can do much better and feel f2 was stopped down way too much.  The flight was extremely accurate and well executed. 

The following flight using the 25m, with a smaller site of about half of the first one was planned at 60 metres for 0.9cm resolution.  On the first flight I dipped into Go to check camera but on the second I did not.

From the camera preview it was very apparent that the images being taken were widely out of focus, it looks like the camera was focusing, but ended up totally out of focus.

Does Map Pilot actually have a focus command? Can we have a detailed description of the process surrounding setting up the X5 as something was wrong on the second flight.

Returning to the first flight and the camera settings, we seem to be between a rock and a hard place regarding camera settings.  

I would like to shoot either A priority or Manual but we do not have A priority or manual aperture settings.

i would like to see an A priority, with a shutter min value which is dependant on motion blur which is already calculated, tied in with ISO so when the EV dips below min shutter then ISO increases to a max set value, after which it's a no go!

Also having full manual control of aperture and ISO is pretty essential to make effective use of the various lenses and the X5

Also when using the x5 and say 45mm, (incredibly good lens, at least my copy is) small area high detail surveys may benefit from the option of raw files. Not practical for a lot, but for example when required to have a high detail with min height restrictions above, inspections etc.

 

 

 

 

John Kearney

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Thanks you very much for the detailed feedback. It sounds like you have all the toys.

We haven't had the opportunity to test the Pro with all the lenses so we can't speak to the tradeoffs and are relying on the math to be correct in order for the overlap to work out properly. We know the 15mm is an asphere so there is already likely going to be a bit of interesting spacing going on.

Going down this path with the Pro is quickly complicating our interface with all the options.

We are trying to pull an autofocus on the center of the image AFTER every image is taken (one before the first one). I guess since the focus is being determined while moving it could be causing some weirdness. We might need to stop and get a focus value before starting but then it won't likely apply to images taken changing terrain.

We highly recommend using Automatic mode for the exposure when there is plenty of light and Shutter Priority mode when you are short on light. We will not likely be adding an Aperture priority mode. If all these modes start confusing people we are more likely to take the additional ones out than add more...

In our experience, playing with the aperture shouldn't really come in to play when mapping up high but it seems that you are operating super close to ground where it might actually matter.

We will not likely be adding a raw readout option either since they take a much longer time to read out and cause large variations in the camera framing availability time.

Elizabeth
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Thanks for the reply, I will re-run some tests with the 25mm to see if I can find out why it did not focus properly.  Maybe the dip into Go and firing off some test shots before handing over to MP.

i have the complete set of approved lenses for the X5 and hope to test those that are appropriate for survey work over the next couple of weeks.

Fully understand where you are coming from re aperture control but I hope you will reconsider, as anyone running an x5 with a variety of lenses is unlikely to be confused with the options as its one of the main reasons for having it.

Lens performance varies significantly (image quality and that's the reason for using the x5 after all) with aperture and that's the fundamental reason for trying to maintain an aperture between 5 & 8.

Would it not be possible to add aperture and ISO control under the i1Pro category heading, even hide the that portion of the menu with a toggle?

 

 

 

John Kearney 0 votes
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I'm just starting to test MapsMadeEasy with my Inspire/X5 and stock 15mm lens.  My first mission had all of the pictures out of focus.  So on the second attempt, I did go up in DJI GO and set the focus.  Then I landed, closed GO and started Map Pilot, loaded the mission and took off.  Of course, I've now used some of the battery focusing and landing and switching applications (Mid flight switch didn't work.  It wouldn't load the mission from memory and wouldn't start the mission.)  So I was half way through the mapping run and had to abort and come back and switch batteries.  Good news was that on the second flight it went back and picked up where it left off and finished the mission.  During the last half of the mission, the camera display was blank and there was no triangle showing the location of the aircraft, but dots were appearing along the flight route so I was assuming pictures were being taken, so I just let the mission finish.  Back on the ground, and looking at the pictures, the first half of the pictures were in focus, but after the battery switch they were all bad again.

I've done a lot of reading about the X5 camera and focus issues.  It seems that the lens calibration in the GO app may have something to do with it.  Many users have the opinion that the lens calibration is stored in the GO app itself.  If that is the case, then this won't work, but I'll try anyway.  There were no authoritative answers on that issue.  There are some detailed instructions on how to get a valid calibration for photos. I'm going to try that again today and see if it solves the problem. ... After the weather warms up a bit outside.

David Whiteley 0 votes
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@ David, most of what you have probably read about any X5 focus issues particularly in regard to calibration is probably incorrect.

Put simply you do not need to calibrate lenses in order for autofocus to work, calibration only matches the app and tx distance settings to the individual lens.

Contrast detection autofocus works on exactly that, no calibration will affect that.

I have 6 lenses and have long given up calibrating them and have zero issues (other than with map pilot) with focus.  I posted some 45mm samples on RCG a short time ago - no calibration and no focus issue, clear detail of the UKs largest offshore wind farm on the horizon, 45 miles away (you do need to zoom the image to 400% to see them, but that's the resolving power of the lens, the x5 sensors and the autofocus system, it was focussed on an object 158 metres away at the time.

Any focus issues beyond a poor copy lens are likely operator error, as a one shot focus system it has its limits and easy to forget when you are also flying an aircraft, speaking from personal experience here, i fully admit to still having the odd brain fade and forgetting to refocus, when a composition changes significantly.

John Kearney 0 votes
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Good information here guys. Thanks for chiming in.

We apparently need to come up with a method for pulling a better autofocus. This might be a pretty big issue on a moving camera and if we start and stop a lot the battery life will go WAY down.

As we suggested before, we could stop at the beginning and pull one focus to use for the whole mission. That is doable but might not work well in rolling terrain or near ground flights.

The reason the DJI lens calibration has you focus on a spot at least 50m away is because that is where infinity begins (at least for the 15mm lens). To be honest, we really didn't do too much near ground testing with our Pro since the GSD just gets ridiculous.

Any suggestions are welcome as we will attempt to address this in a future release.

Elizabeth 0 votes
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Thanks for all the good information. After some more testing and learning, I've discovered that my main problem was not starting with the DJI GO app.  Reading your procedures carefully it says to open the GO app to make sure everything is ok, then close it and go to the Map Pilot app.  I've been starting with the Map Pilot app alone and that is when I have my focus problems.  Starting with the GO app and setting the focus to infinity seems to work well.  My camera has a tendency to start in the wrong position anyway.  Many times, after its usual initialization, the camera will rotate all the way around to the right to the limit and that is where it starts out.  If i click the C1 button (programmed to reset camera yaw) it will swing around to the front again. (Looks like I may have some more learning to do here. Don't know why it does that.)

Anyway, I've noticed that some settings in the GO app remain with the Map Pilot mission such as ISO and camera settings as well as the Free/Follow gimbal modes.  I've noticed that when in Free mode the camera may be at an odd angle and not perpendicular to the flight path and stays that way through the whole flight. Seems like that would invalidate the overlap and sidelap settings.  For me, I think my focus problems are solved by starting with the GO app. Thanks again!

David Whiteley 0 votes
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Hi everyone.

Yesterday I flew a mapping mission of a steep hillside, using my Inspire 1 Pro/ X5 stock lens.  I had the Terrain Following option activated (60m AGL) and motion blur compensation turned on.  It was a bright sunny day with low winds.  PERFECT for mapping.  The site was in a remote area without Internet/ GSM connectivity so I had pre-cached the maps.

 

The mission was supposed to take 1 battery (16 mins) but actually took 2 as the auto-focus slowed the craft down considerably.  I was delighted to see that the Terrain Awareness worked perfectly!  (Well done MME Team).  However, reviewing the imagery, I see that all of the images are so badly blurred they are unusable.  Also, the map pilot app did not place photo dots at every point of the mission.  I didn't think much of that, but now that I am back in the office, I see that some of the images are actually "empty" (a file created with no coloured pixels - all white).  I don't know what happened, but I now need to return to the site and probably fly a manual mission.  That is extremely disappointing as it is a quite a distance away.

I will disable the auto-focus and leave Terrain Awareness on.  I will also try the same mission with a P3 to see if that makes a difference.

 

Tudor/ Ryan:  it is very important that the X5 auto-focus works reliably.  Please keep us updated on your progress.  Thanks

Peter O'Regan 0 votes
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The focusing on the various lenses ranges from pretty good to horrible. Throw in that the autofocus is done on a moving target and you are found to get some out of focus images. For any lenses other than the 15mm that comes with it we recommend using manual focus setting on the lens and in the setting. Unless you are flying at low altitudes setting it to infinity should be fine. 

The new version (2.3.0) that should be out very soon will have a way to force the focus on P4 Pro, Mavic and X5 (two finger tap on the video preview). This will allow you to pause the mission and do an autofocus even if the autofocus setting is turned off in the settings.

Peter: The Terrain Awareness feature is what is slowing the aircraft down. Elevation changes do slow the progress substantially and that is not something we are currently modeling.

Map Pilot has nothing to do with the blank images though... That is internal to the camera. Make sure you are using the highest quality SD cards available on that camera.

 

Zane 0 votes
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