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Understanding Camera Calibration
1250 1 2018-6-14
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PeterHammond
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Flight distance : 10190 ft
United Kingdom
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Hi, Im a bit confused about other threads I have read regarding the X5 camera calibration process so any information or corrections would be appreciated.  Most videos I have seen sugest calibration on a high contrast subject thats 50mtrs away (some are sugesting a lot further), I dont understan the logic behind this as it doesnt represent the hyperfocal distance of the DJI 15mm stock lens at all, to clarify my knowledge a little further;
Using the DJI 15mm stock lens as an example with a subject 10 metres away my calculations as a photographer would be as follows

Subject Distance 10m

Aperature F1.7.                                                    Aperatue F5.6 (optimum quality for this lens for both centre and edge sharpness)
The hyperfocal distance of this lens is 8.93m          The hyperfocal distance is 2.67m
Depth of Field in Front of subject       5.28m           Depth of field infront.       7.90m

Depth of Field Bedind subject            oo Infinity     Depth of Field Behind.      00 Infinity

Bearing in mind the above facts regarding subject distance, depth of field both and the hyperfocal distance (sharpness in front and behind subject) can someone tell me why the calibration requires the subject to be 50mts or further away as this is technically squandering the benefits of the hyperfocal distance of the lens.


Im probably missing the point here but I do read that a lot of X5 users are experiencing problems with their lenses even after calibration.  I realise that most of you will probably be on the Inspire 2 now but for those still on this craft and for me as a Newbee some more information would be nice (also have the inspire with X3 where calibration is not relevant).

Also I plan on buying the Oly 25 and 45mm lenses do either of these require a balancing ring if used with an ND or haze filter (I assume not). Some clarity here would be nice as I dont want to damage my new craft.
2018-6-14
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fansa84fe8a4
First Officer
Flight distance : 3 ft
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Given that a drone will likely be much further than the near hyperfocal point, it pretty much is a moot point to rely on doing this for an aerial camera.  Just calibrate whatever focal length lens at 50+ meters and you should be good to go.  I'll add that I also have the Laowa 7.5mm lens and infinity focus had I relied on hyperfocal would not work as it would not hit infinity with manual focusing as some Laowas' are prone to this and dpreview had some owners put a paper shim in the back element section to move the lenses back so infinity could be reached.  I sent back one for not hitting infinity and second one was better, but it took a shim on the X5S.

As to balance, it can differ from what DJI recommends.  I have the X5S and it has a lot of heating-sinking goop (Both a blue and clear variety and I doubt it is measured going in.)  inside it that makes the suggested balance ring off a bit so I Velcro a penny on the back and off to one side as well for rotation too.  You should do the hand balance and see how it rotates as well as tilts and adjust to your camera and gimbal.

DJI has more serious issues with magenta tint matters and no ability to adjust it in their camera settings as with better video cameras.  So I fly with a green correction filter for manual white balance and it affects the balance good or bad depending on the lens selected.  Been an issue for several years now.

2018-6-14
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