I’ve been getting photos to assemble into a plain picturre/map and found that many of them aren’t in great focus. next time i fly i’ll have to examine what the app is saying…but i do know it appears to be in m anual focus mode. I didn’t check to see if it’s set to infinity. I’m regularly setting my flights to be 100 110 or 125 feet above take off height, and my take off point is normally right near my first waypoint. i guess i figured it was computing focus somehow from the take off height vs current height… but just a guess.
I’m shooting to get the finest detail i can and still avoid tree tops, so i’m running just under 7mph for the speed.
I did notice the it’s going at 100 ISO…so obviously , that could cause blur. I’m thinking I’ll take my filter off the lens to see if it runs that iso up a little higher.
anyone able to chime in and discuss what to do to maximimize focus? like changing flight to above ground level, slowing down, or messing with some otgher setting? thanks
At this time, the pilot is responsible for setting the camera’s exposure and focus settings (manual focus has to be set via DJI Fly as it’s not yet supported in Litchi Pilot).
The only camera settings Litchi Pilot sets at the beginning of a flight is the capture mode (photo or video) and in photo mode, it also sets the resolution to 12MP and aspect ratio to 4:3.
The lower the ISO the less grain or noise you will see in the photos. What may cause blur is a slower shutter speed.
What kind of filter are you using? If you are using an ND filter, their only purpose is to limit the light getting into the lens so that you can lower the shutter speed to introduce motion blur. If you want to minimize blur, do not use ND filters.
I did find how while in litchi app, i can set the iso and exp speed on the fly. I’m going to study more to see how to get the cam to default to settings vs setting them each time i take off to do mapping pics. it has the ability to lock the shutter speed and then auto adjust iso speed, and vice versa depending on your needs.
I’m going to study all the pics to see how bad the blur is, and then do some experiments with different shutter speeds to see what it takes to make it go away (I’m sure it will depend on the drones travel speed and ambien light, but i want to find a ballpark value to get started at least)
A polarizing filter reduces light entering the lens by 1 to 3 stops. If the drone is traveling at 7 MPH and the shutter speed is 1/125, the distance traveled while the shutter is open is 1 inch. At a shutter speed of 1/500, the distance traveled would be 0.25 inch. To minimize motion blur you want to use a fast shutter speed a relatively slow drone speed. Removing any filter will help to maximize shutter speed.
Have you looked to see what your current shutter speed is?
by default the auto setting it was doing it was running 1/60th so i know it’s way too low. And for what I’m doing, I can pull the polarizing filter. I’ll look for the stock thing as it may be clear glass… (just want to keep dust out).
If i understand correctly, i want to set shutter either at like 120 or 240 (i think were listed options). and go from there.
i can also slow the drone down. I’ve found for what i’m mapping, i used close to half a battery for the area… so if i slow down, i should remain within a battery flight time
I’m also trying to figure out what the real resolution capability of the camera is… I was trying to get to like 1/2" per pixel. I’m not sure that flying at 100 to 125 feet that’s possible with this drone. I don’t know if i can get that with optical resolution…or if it’s doing digital resolution zooming.
i’ve also learned when making drone flights… leave at least a few minute gap between flights so you can separate your flight pic groups
I’ve been playing with the settings via both litchi pilot and dji fly. i believe i’ve got it worked out how to set the ss and then leave iso at auto.
i’m wondering now, though, is the best focus setting for what i’m doing. I’m flying over areas with some trees, but I’m mainly trying to focus on the ground. The trees are primarily leafless now.
I guess my hope is to have the ground level set in focus, and if the trees go in and out of focus.. i can live with that.
i can’t tell if litchi hub is telling the drone (hey, you are set to fly at this altitude, so set focus correspondingly, or if the drone is using its functions to focus).
i’ve read stuff on the focussing modes on the drone, but for the way the mapping is working (it never stops, just flys along at 5mph and takes pictures at the locations it’s supposed to), so what would be the correct focus mode for that? or… do i have to find the switch to tell it to stop at every point so the autofocus would focus at each spot (and would risk focusing on treetops if it’s parked over a tree)
The configurations in a waypoint mapping mission do not affect the focusing of the camera in any way. The wide angle of typical drone cameras have a rather wide depth of field. There is a good chance that both the trees and ground will be in focus. If you want to specifically focus on only the ground, you could put the camera focus in manual mode and once the drone is at the mission height, tap on the view of the ground on the screen. This should set your focus for the remainder of the flight.
You had also asked about determining both the GSD and the distance traveled during photo exposure based on drone speed and shutter speed. I have an on-line calculator for mapping missions that may be of interest to you. It is available here:
Do not use any filters. Use the automatic mode on your DJI Fly device for all exposures. Unless it’s a large body of water, you shouldn’t worry about water reflections. The altitude can generally be set between 80-90 meters.Do not use any filters. Use the automatic mode on your DJI Fly device for all exposures. Unless it’s a large body of water, you shouldn’t worry about water reflections. The altitude can generally be set between 80-90 meters.
thanks I’m chiming in on my own post… from what i found, changing between mf and afc didn’t make a huge difference in the photos taken from the drone.
I ran my tests a couple of times at 100 and 125 feet above take off. image of ground was roughly similar.
i also played with my shutter and set to 240 and 400 and didn’t get a huge difference in quality.
in a very quick test, i could tell the one thing that would help the image is flying lower, but unfortunately, where i need to map, i have to clear trees, so it will be tough getting the drone lower for the better shots.