Camera/lens optimization service??

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There's a few good threads on how to adjust the camera board or lens. And I'm almost willing to open up one of my P3s to try to improve the image quality.
But I'm no expert and my fear is I may make things worse rather than better.

Is there anyone in out community who REALLY knows what they are doing specifically with optimizing the camera - and would do this for a fee?
I'd consider sending one of my P3s for this.
Yesterday I took my main bird out for a test as I'll be traveling next week and hadn't flown since November.
I've always felt that this one (an new camera after a crash) was not as sharp as it should be.
I did a few shots around the area and looked critically at them and see that things in the foreground from day 35-60' height are quite sharp. But buildings in the background - in this case maybe 300/500' away seemed not tack sharp.
I did a few frames pointed straight down from same height and corner to corner and middle of cats & parking lot I was over seemed pretty **** sharp. I was expecting maybe off on one side or the other.

So, conclusion is, maybe lens is not perfectly focused for infinity. Which means popping the whole lens & board assembly out, breaking the locktite on the lens threads and adjusting.

I'd rather pay someone- who is experienced- to do this.
A tweak on the board screws is simple. The lens adjustment not so much.

So- anyone....?


Sent from my iPhone using PhantomPilots
 
hi sir...I've broke the locktite on my p3a advanced lens and turned it slightly ccw and have found considerably sharper images across the frame...but have yet to resurcure the lens to mount that gets screwed to sensor board.

my images were soft on the edges and somewhat better in the center.

I think I've found a good combination of sensor board placement and focus from lens onto the sensor.

now I think I'll disconnect ribbon off sensor board from gimbal motor in order to not move sensor board alignment so I can reglue the lens to the mount.


Sent from my iPhone using PhantomPilots
 
I took a look at more images - in better light - and now see that my focus overall is not bad - except for softness in the upper right corner.
Which means the board placement probably needs to be adjusted slightly. Looks like my center of sharpness for the lens may be skewed slightly so that upper right is out of the sweet spot.
Center and other 3 corners seem pretty good.
Here is the full size shot and the 4 corners.
If anyone has feedback on this I'd appreciate it.
Processed in Lightroom with defaults - Chromatic Abberation & Lens profile checked.
Top one is full size uncropped image:
The corners I'm posting at 100%
1-051_102816_Lind-FullSize.jpg 2-051_102816_Lind_UpperRightCorner.jpg 3-051_102816_Lind_LowerRightCorner.jpg 4-051_102816_Lind_LowerLeft-Corner.jpg 5-051_102816_Lind_UpperLeft-Corner.jpg
Full shot:
1-051_102816_Lind-FullSize.jpg

Upper Right - see severe blur in trees in corner:
2-051_102816_Lind_UpperRightCorner.jpg


Lower Right - pretty sharp as are the center and other corners.
3-051_102816_Lind_LowerRightCorner.jpg

Lower left:
4-051_102816_Lind_LowerLeft-Corner.jpg

Upper Left
5-051_102816_Lind_UpperLeft-Corner.jpg

At this point I dont think I need to adjust lens - just the board to get the sharp part of the image centered more- but welcome other opinions....

thx
 
On my P3P I had an overall decent focus and corner quality, but I was intrigued by the process of adjusting the lens. So, I went ahead and took the camera apart, loosened the thread on the lens mount and re-assembled it to the point where it is possible to turn the lens with needle nose pliers. Here is what I found:
First, do NOT tighten the board screws too much. Doing that tends to cause corner blur and more than usual chromatic aberration. I loosened the board screws completely again and then re-tightened them to a point where I felt increasing resistance and stopped.
The process of peaking the lens focus is tedious because it is paramount to repeatedly take full resolution stills of an appropriate subject and checking them in photoshop for sharpness and clarity until you feel that the lens is optimal.

In my case I found that not only did I manage to increase image clarity and focus, but I also reduced corner problems to a point. So far I have not relocked the lens, I feel it is tight enough and should not move. I may have to go back and deal with that later.
 
What's involved in loosening the lens- how do you break the locktite? Is it just that when the lens/board assembly is out of the camera body just a matter of turning the lens to break the seal?
Also how do you avoid damaging the cable that attaches the inner camera to the Gimbal?
Have to look at that video about changing the lens again...
 
First, figure out how you are going to peak the focus once you have broken the locktite. I used a printed resolution chart (several pages to make it large enough) along with a good light source to highlight it and attached to on the wall about 25 feet away from the drone. Then, before starting the procedure, I took a raw picture of the chart and checked it out in photoshop without any processing. You need to be able to zoom in on the picture at least to 200%, but better at 400%.

Break locktite:
It is not that hard - maybe a bit hair-rising.. Check out this video:
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Having gone through it, here are some additional recommendations: First, make sure not to touch any glassy surfaces (sensor and sensor side of lens) and keep it real clean. You do not want to have to physically clean the sensor for sure (very delicate surface). Once, the sensor board is out of the way and the black lens mask/cover is removed, gently push onto the front of the lens using a lens towel. It takes a bit to break the glue that fixes front of the lens to the camera body as well as the lens mask. I had to use an exacto-knife to carefully cut through the excessive amount of glue on my camera before being able to push the lens out. Also, use the exacto-knife to make a small scratch on the lens ring that matches up with a dot you make using a fine-tipped felt pen to mark the current position of the lens relative to the lens case. It will help you during the adjustment process as a starting point. Once out, do what is shown in the video to break the locktite and turn the lens back and forth about 1/2 turn 2-3 times until it turns a little easier. After that re-install the lens and the sensor board. Make sure to not over-tighten the sensor board screws. Only "just-tight". Put the back cover back onto the camera (the gimbal will not work correctly (vibrate) without that cover!). Leave the front of the lens free to allow it to be turned using needle-nose pliers.

Adjustment:
There is really no way to peak the focus using the real-time video feed from the RC. All you can do is get within range, but given the mark you made prior to breaking the locktite will already put you in range. To peak the focus, take a picture, then turn the lens a minute amount (about 1/8" clockwise) and take a picture, then once more the same and take a third picture. Take all three into photoshop and compare. The result will show you if you are moving in the right direction. If not, reverse the direction and repeat the process. Once you are getting closer, to the peak, take only single pictures between very small movements (about 1 mm) into photoshop to check focus. As I stated earlier, it is tedious. You can keep the bird powered up during the whole process and just keep taking out the SD card after each picture (or picture series).

After completion, I just put the lens mask back with a light push (is is positional using two small extrusions), then screwed the filter back on. So far so good. Due to bad weather I have not flown the bird yet, but taken some video walking with it. Looks real good. I think it may well be necessary to add some non-hardening glue to the outer lens ring and the camera body. Since there is a small gap it is possible that without some glue the lens could vibrate. So, I may still do that, but there is definitively no need to reapply locktite to the lens thread.

That's it.
 
Well, I did not wait for better weather. At the most convenient "calm" and drizzle remnant of the storm, I flew a small "around-the-house" mission to verify that in fact the video is really better and that the lens does not "move" or "vibrate" even if not glued back down to the camera case (yet). Result is phenomenal! Really sharp clean video - even though I shot it at "0-0-0" with super sharp results there is extremely little "pixel crawl" and scoping it in Resolve and Premiere there is much less mpeg artifact around small high-contrast patterns. Seems to me that even a slight lens blur is quite detrimental. Until these shots taken, I've been using "-1,0,0" and even applied a light "softening" in Premiere (-5) to get a very clean looking video.
I believe now I may be able to continue using "0,0,0" and possibly no softening needed (still need to verify at different lighting etc).

Different subject: I know the prevailing wisdom appears to be that it is better to go softer when shooting the video (-2,-1,-1) or similar and then bring it back during the grading slightly sharpening the image and more. Turns out the compression algorithms settings used by DJI make the compressor rather "lazy" causing a lot of color blur (smear/water-color painting effect) when using -2 sharpness let alone -3. In post processing it is really not possible to "bring back" what has not been recorded. Post process sharpening does not do well and ends up enhancing mpeg artifacts.
 
What's an example of "non -hardening glue"? And will the screws holding the sensor board in place need anything like locktie to keep them from shifting?
Thanks for this. I'm definitely going to try this on my #2 P3 first, then if I don't totally screw it up, then on my main...
 
Well, non-hardening was a poor choice of reference. What I meant is a glue that remains somewhat flexible. Let's say an epoxy glue would be the wrong choice as it would make actions along those lines impossible. A drop of that glue to each of the board screws work just fine. If you have some locktite handy, use that instead. So far, I just put those screws back without extra locktite. I hope they will stay in place since they are only lightly tightened.

Btw: I have a 65" 4K (LG OLED) TV and I used the attached 4K resolution chart, displayed on that TV with the P3P at 15 feet distance. For more precise comparisons, I enlarged the resulting images to 400%.
4KResChart.jpg
 
Nice chart. Thanks. What's the actual res on this?
Don't have that large a monitor or tv. And safest place for me to work on this is my basement office.
But I think I can put this in Photoshop and convert to an EPS doc, then scale it up. EPS format is designed for scaling flat art or text up without loss of detail.
I can then print out and piece together the 8.5"X11 pages to make a decently large target. Or several to place at 4 corners and center of frame.
Can definitely get 15 back, and I'll be able to easily shoot & view my tests and keep in a relatively dust free environment while working with camera back off.
I appreciate all the detail you gave here.
 
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Just rewatched the video about replacing the lens. And the last bit about focusing has you doing the test while connected to the iPad. Just realized I can probably connect my controller to my MacPro and do prelim tests almost live -shooting frames and viewing live in Go on my 27" monitor. At least to determine which direction to go initially. Realize that it won't be full res- but enough to get close - before pulling the card & viewing the full res files in Photoshop.
 
Yes you can use the live feed to get close, but you will find out quickly that the quality of the live feed is unfortunately quite poor. So, I ended up using my prior lens position mark as a start. Remember, to free up the lens thread, only turn the lens back and forth about 1/2 turn from original position. That way, you don't end up getting pretty much to your original setting after matching up the lens ring mark with the one on the camera case.

As far as the resolution of the chart - it is unfortunately a jpg version although 4K resolution. It looks sharp and clear when displayed on the 65" 4K monitor. Converting it to an EPS doc may work - I have not tried that. Also, printing it using a number of 8.5x11 page segments and pasting a wall with it might work quite well, most likely better than my 65" display short-cut. Measured diagonally, the 65" display only uses 1/5 of the p3p image taken at 15' distance. The p3p picture "sees" about 26.5 feet diagonally at a 15' distance. To demonstrate actual 4K resolution of the p3p camera the resolution chart display would have to cover an area roughly 13' by 23' taken at 15' distance. That is not very practical.
 
Converting to EPS worked very nicely. I Upres'ed it to 20" wide @ 300 dpi. Feel free to download here - anyone:
Dropbox - Large Focus Test Chart-20in Wide.eps
Then applied a bit of Unsharp mask. Looks pretty good. I will tile together a large chart & place several on my target wherever I do it.
Unfortunately my basement is barely 6' high to ceiling.
I may have to take it to my back porch or yard & put targets on the garage wall.
Just seemed like such a great idea to be able to go from drone to desktop easily. But I'd guess to get optimum focus I don't really want to be closer than 15'. I know people have done so - but it seems counter intuitive since everything we shoot is from a much greater distance.

Do you know what the actual "Infinity" focus distance for this lens is?
Just a pain to go back & forth to my good display in the basement. Also I worry about dust. But I can throw a cloth over the drone while leaving it in place. At least the back of the camera will be all closed up at that point.
 
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OK then Here another link.
I Up-res'ed the chart up more - 37.33" x 21" @300dpi.
Which is about 12 sheets of US Letter- 2 rows of 6
Dropbox - Large Focus Test Chart-37x21in Wide.pdf

If you open it in Adobe Acrobat Reader you can choose "Poster" printing and it will tile it for you. I am printing mine now to see if it works.....
 
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Oops. Duplicated last post. I erased this one...
 
Roamer105- earlier in the thread Hammer 737 mentioned he might loosen the cable to the sensor board so he could reapply locktite to the lens to keep it from shifting.
Do you think the lens will move in day to day transport or flying - or are the threads snug enough that's it's unlikely to move on its own?
And is it necessary to remove that cable to do that?
 
One more question (isn't there always?) -in the video it shows and says on screen just before unscrewing the sensor board- "pry the Glued lens covering off" - that's the ring that once removed allows room for the needle Nose pliers to grab and rotate the lens for focus. Will that ring need any glue put back on at the end to keep it in place as well- or again, is it pretty snug when back in place and really doesn't need actual glue? Especially as the UV filter is screwed back on over it?
 
Sorry- just reread this part-already answered me...
I wonder if something like rubber cement might be good to hold position, yet remain flexible and easy to remove or cut through if more adjustments ever needed?
What glue will you (or did you) end up using?
*********************
After completion, I just put the lens mask back with a light push (is is positional using two small extrusions), then screwed the filter back on. So far so good. Due to bad weather I have not flown the bird yet, but taken some video walking with it. Looks real good. I think it may well be necessary to add some non-hardening glue to the outer lens ring and the camera body. Since there is a small gap it is possible that without some glue the lens could vibrate. So, I may still do that, but there is definitively no need to reapply locktite to the lens thread.

That's it.[/QUOTE]
 

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