Camera/lens optimization service??

[jephoto]

Roamer105- need some advice. I finally got ready to do my test. Set up my targets in the yard. Nice sunny day with little wind.
Did my Before shots - and definitely things are soft (on my spare P3) .
Started the process - but am stuck at unscrewing the 4 black Phillips screws for the main board. They are so tight I am afraid of stripping the screws. May have already compromise one of them.
I don't have the finger strength to turn them while keeping pressure on the screw. How did you get yours undone???

 

[Roamer105]

It is very critical to the correct size/shape phillips head screwdriver. I have an old Radio Shack 21 piece Precision Driver Set that works great for all of the Phantom type screws. General Ultra Tech tool system is another possible choice. The screws have thread lock on them so they do need to be "broken loose". But, here is another possible way to deal with it. The 4 board screws actually fix the sensor board to the lens mount, so if you unscrew the lens mount AND disconnect the ribbon cable you should be able to take the lens, mount and board (pushing the lens inward). The lens, mount and board will all come out as one piece. Then, carefully break the thread lock on the lens mount. That may be a bit more tricky since the sensor board is attached to the mount.

 

[jephoto]

Got a friend with much more hand strength- going to see if he can do it first. Rather not disconnect the cable if I don't have to.
Looks a bit delicate.

 

[jephoto]

And like it might be a ***** to get back on...

 

[Roamer105]

I don't like how Youtube messes with the video quality. Here is a better way to show clarity and sharpness of the video. I grabbed 3 frames saved them in full resolution JPG and attached them here without additional manipulation.

 

[jephoto]

Got them off. Two of them slightly stripped. I can put them back but worried if I need to remove again. Although I won't put them in as tight.
Tried to find out size of screws from DJI. Wouldn't tell me. "Only the engineers know that" and "have ton send it in for repair"

Screw that.
Anyone know the specs on the 4 black screws holding the sensor board to the lens mount?
Maybe I can find locally.

 

[jephoto]

If you know- which direction focuses closer and which farther? I marked approx where I thought my original focus was. But now that I have it back together it's focused about an inch from
Camera. I've Gone both counter and clockwise maybe within 1/2" and still focused very close.

 

[jephoto]

Seems to be clockwise. But I'm now about 100° past where I thought I was originally and still only focused about 9-10" from lens. Hope I can turn it enough to focus ...

 

[jephoto]

Ok then. Not sure what to do. Pulled the lens back out. I had already screwed it down clockwise as far as it will go on the board. But does not seem to be enough. That seems to be the correct direction but it's way to close. About 10". And when I put the lens back in and the sensor board on it all seems to fit nice & snug. No play really that I could adjust board.

 

[jephoto]

I don't like how Youtube messes with the video quality. Here is a better way to show clarity and sharpness of the video. I grabbed 3 frames saved them in full resolution JPG and attached them here without additional manipulation.
View attachment 80658
View attachment 80659
View attachment 80660

Beautifully sharp. I know it's possible. Just don't know why mine is now so close focused. Can't figure what I did different putting it back. Really looks like it's all correct.

 

[Roamer105]

Actually I can't tell you if out or in is focusing closer or farther away. I simply tried to do better from where I started. I may have moved it maybe within 1/2 inch or less in either direction. Ultimately I moved it only about 1/8 or less of an inch to optimize.

 

[jephoto]

That's what I expected. And I swear I put it back as close as possible to my "Before" position. I used a extra fine point sharpie to mark the O° mark at the top of the lens. And started there. But it was sharp focused at just under 3"
At first I tried small 1/8" movements, but barely changed the focus point, so I went bigger. Until I ran out of thread.

Opened it back up and checked everything. There really isn't any play in the sensor board or lens mount that I can tell. Just don't get it. It wasn't tack sharp before- but not focused at 3-10" either.

 

[jephoto]

Just had a thought. I assumed the sensor board needed to be screwed down all the way- until the screw stops. Since they were locktite glued in I really don't know if they were all the way down, is it possible that I now have the sensor board too CLOSE to the lens, that I need to back off each screw a turn?
Tomorrow I will experiment with that.

 

[Roamer105]

Watch out for that black rubber seal between the board and the lens mount. It may have folded on you or worse...

 

[jephoto]

Saw that. I don't think that's it, but will double check

 

[jephoto]

Ok. Fresh day. Gasket was fine. But by taking it apart and putting back together I made progress.
But coming to the conclusion that this lens may not be able to focus out to infinity.
In my basement I seem to have sharp focus out to about 19'.at 22' seems worse. Going to take it outside for real world test. Problem is that I am at the max I can turn the lens in clockwise direction and I think it needs more.
In other words closer to the sensor. But sensor board is now down snug and pretty sure I can't get it any closer. It may just be fubar for this lens.
Too bad I didn't just return it last year after my first shoot with it. Now it's out of warranty even if I hadn't taken it apart & messed with it.

 

[Roamer105]

Well, there is most likely a significant spread in production tolerances with this lens and you may be stuck with getting good focus but not quite infinity. Question: Is your lens screwed in all the way and you can't simply go any further? The method used to peak the lens focus clearly favors a medium range distance (in my case, I focused on a chart at about 15' distance). Given the focal length of the lens, the hyper focal point is much closer than that (maybe around 4 feet or so). This means that everything beyond 4' should be in focus. With this camera and lens I noticed that even with best focus, there is going to be some amount of increased mushiness the farther away object are. This is simply a consequence of sensor limitations and lens/glass/plastic quality. In the case of the P3P, the lens sharpness and the sensor resolution-to-size are probably quite well matched, both pushing their respective limits.

 

[jephoto]

Well. I may want to tweak it. Yes - I am threaded in as far as it will go clockwise. CCW made it way worse.
Anyway - it seems much better now. Doing it outside was the real test. My center and left side are way improved. Upper & Lower right a bit mushy - I think a slight tweak in the Sensor board position may do the trick. But this is still better. Before my center of the frame was mush.
Here's my results.
Overall scene. Lightstands with targets approx 25' from camera The Before/After's are 100% crop

:

 

[jephoto]

Meant to update this. My first tests since the focus adjust:

Quite happy with the results. But then discovered a stress crack from LED to tip of the arm through 2 of the motor mount screws.
So, I'm in process of replacing the shell.
Progress.....