where to see camera lens info?

[alistair]

First my apologies if I have posted this in the wrong place.

I have been researching but don't see the info I am looking for.

all the info I can find from DJI is = FOV 84° 8.8 mm/24 mm (35 mm format equivalent) f/2.8 - f/11 auto focus at 1 m - ∞

As a long time professional photographer I am used to being able to find info on lenses that I buy or might buy appertaining to the image quality at various aperture openings.
since the Phantom 4 Pro is using a camera with a range of f/2.8 to f/11, and, if the normal lens characteristics apply, I would expect the "sweet spot" to be at f/5.6 or f/8 ,that being the spot where the lens is sharpest from edge to edge.

I would also wonder how much, if any, diffraction there is at f/11?

I have noted on some reviews some comments on lack of sharpness being put down to not being focused on the right place or the subject , but I have not seen any mention of any depth of field effect being the cause by using as wide open aperture as possible.

For example with the focus point at 10 meters away from the camera at f/2.8 you get:-

Depth of fieldTotal: 16.79m (6.83m ~ 23.63m)
In front of subject: 3.77m (22.4%) Behind subject: 13.03m (77.6%) Hyperfocal distance: 19.18m (>9.59m)

but at f/11 you get a DOF of :-

Depth of fieldTotal: ∞m (3.35m ~ ∞m)
In front of subject: 7.25m Behind subject: ∞m Hyperfocal distance: 4.88m (>2.44m)

note the at 2.8 infinity is not in focus but at f/11 it is .

Any way my real question is is there any tested lens data available anywhere?

 

[Meta4]

Any way my real question is is there any tested lens data available anywhere?

Testing by members back soon after the P4 pro was released showed that there is no real sweet spot.
The lens is very good from full open to 5.6.
Depth of field is not of much concern in aerial photography because the lens has a lot of DoF at any aperture and you would very rarely focus as close as 10 metres

 

[GMack]

Since you will be using the flying camera at a further distance (>30') I doubt the DOF will play into your shots.

The bigger problem I've had with the DJI cameras is they are prone to have an excessive tilt at the sensor which causes one side to be less sharp than the other, i.e. sensor is not parallel to the lens mount or elements. It's happened to one P4 and also my X5S on the Inspire 2. DJI isn't known for quality control and often their products are rushed to market.

Most useful thing I've used is a USAF Resolution Chart I bought from Edmund Scientific for $40 and mounted it in a frame ( Resolving Power Chart | Edmund Optics ). WIth that I can check the resolution of the lens in the center and corners, stop down and see how far I can go before diffraction bothers me, and see if it has any DJI Tilt by putting the camera into Focus Peaking mode and watch the edges of the chart while adjusting the focus (With the DJI cameras that allow for manual focus in GO 4.). If the camera is any good, the entire chart should go red at once, and not sweep across with red from one side to the other as you scroll the focus slider which indicates tilt being present.

Good luck as it really is a pot luck with DJI products.

 

[alistair]

Thank you every one for the answers