DUAL LENS CAMERA - BOKEH EFFECT, FAKE SOFTWARE EFFECT

maravilha00

due to largely commented problem of many chinese smartphone fake dual lens cameras, i would like to obtain a clarifying technical explanation from UMIDIGI, how actually we can know if this dual lens camera has really any fonction? as per testing videos available on youtube, the bokeh-effect is a software effect, i.e. focus is centered and all around is blurred. a real dual lens camera allows the user to freely chose which area on the picture he wants to have in focus and the background blurring level also can be adjusted directly on the screen before shooting the picture.

can somebody from UMIDIGI explain and/or confirm that this is/will be possible on UMIDIGI S2 PRO camera ??

maravilha00

tallnutt replied at 2018-3-27 11:18
P.S> so, therefore, ALL dual camera bokeh effects are actually 'fake' compared to a real narrow dept ...

you are right and not right stating all dual lens cameras have fake bokeh effect...
let's again explain what a dual lens camera does, or at least should do:
the main lens takes a mostly sharp picture (main focus on main object within the shot), while the second lens does a second shot form the slightly different viewing angle. this allows a corresponding software to calculate a so called "depth of field" map. based on this map and the main picture, an appropriate software can calculate where the neat main object shall appear and from which point on into background the blurring has to be produced. by the way, a performant software will increase the amount of blur the further into background it goes.

that's the reason why i stated in several posts, that the S2PRO could include a better software allowing to produce good portrait / bokeh shots, as you showed in another post, the 2 rear cameras are recognized which definitely means they COULD be operational, if an appropriate software was included. that's actually definitely NOT the case.

where you are right about "fake" effect is the fact that ALL phones must produce this effect with software to obtain a result as close to a real DLSR camera as possible. Some are better than others, obviously. even on Iphone X these bokeh pics show mistakes, i.e. areas which should be blurred are neat ...

tallnutt

maravilha00 replied at 2018-1-19 06:44
actually it turns out that the bokeh effect on s2 pro as well as on s2 is FAKE, just a round area  ...

Yes it is fake - the second camera does something, but it does not take a lower F stop photo to make the bokeh like you might expect - it cannot combine with the main camera optically, that is not possible with a phone's camera (even the VLT in Chile has trouble optically combining images).  The bokeh effect is software generated, slightly bettter than you get from a sinlge lens camera, but still not a proper bokeh. The simple give-away evidence for this is that if you make the "in focus" centre subject something you can see through parts of, e.g. some flowers, and put on the maximum bokeh effect, you will see that between the banches, the background is still in focus - in a  real low f-stop camera lens , the background will be out of focus between the branches, regardless of where its is (centre, edges, etc.)

I think the second camera just takes a blurred picture and then it is software combined with the main camera focussed image, so that the centre is only from the focussed camera and the edges fade into the background, unfocussed, camera -  but this will never be as good as a real bokeh DSLR type picture - you cannot easily do that by combining two pictures, not without masking all the foreground subject before combining, which is hard to do with e.g. a flower. So the compromise is that the forground sharp area is simple defined by a circle of variable size, defined by the slider.

Hope that clears things up.. although I don't know why Umidigi couldn't explain it before.

maravilha00

tallnutt replied at 2018-1-18 11:27
Edited by tallnutt at 2018-1-18 11:44 \n\n
oops I said it was fake but its not - its does alter bok ...

actually it turns out that the bokeh effect on s2 pro as well as on s2 is FAKE, just a round area neat and in focus and all around that area blurred.... this effect can be done on any simple photo editor within seconds on any picture.
real bokeh / portrait mode would use the second camera lens to create a "depht of field" diagram based on 2 stereoscopic images, allowing to know exactly where the main suject has to be in focus and also what is foreground (in front of
the main subject) and background (behind the subject). this diagram allows then a correct stock camera app to introduce blurred areas BEHIND and IN FRONT of the main subject.... NO ROUND FIELD I FOCUS but pretty much same
effect which can be obtained easily an any SLR photo camera!!

UMIDIGI DEVELOPERS: if the second lens is really an operational lens why don't you simply update your stock camera app and include the necessary software instructions which at least on the S2Pro would take advantage of the hardware.
as per info from the processor manufacturer the hardware allows use of dual lenses up to 16+16 Mp ....

i am very curious to hear from the development team what they have to say about this.
thanks.

maravilha00

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kajsa_katt replied at 2018-1-20 08:13
Edited by kajsa_katt at 2018-1-20 08:31 \n\n

well, thisone goes to the administrators (e.g. http://community.umidigi.com/space-uid-242063.html) of the forum, hopefully they will pay attention and transmit to the UMIDIGI developers.
there are at least 2 major companies which supply the necessary knowhow and corresponding applications for dual lens camera cellphones:
- corephotonics
- arcsoft

coresoftonic on its website has an excellent demonstration how a real bokeh/portrait picture looks like, here it is:
http://corephotonics.com/products/digital-bokeh/
specially when you click on "far focus" it shows clearly the girl's face and body neat, but the foreground (her hand) and the background get gradually blurred,
exactly like on a portrait picture taken with a telelens on a SLR-camera!

arcsoft has also the necessary knowhow but they do not show samples on their website, only general information and for more details you can contact them:
http://www.arcsoft.com/product/d ... on-smart-phone.html

so, as UMIDIGI says they use one lens 13MP and the secondary lens 5MP both together would clearly allow to take real portrait/bokeh pictures, the 13MP camera
takes the main shot and in focus, while the 5MP takes a slightly different angle view based on which a "depht of field" calculation can be made by the software
and then produce the portrait/bokeh picture with less or more blurring of fore- and background.
that's the way how it should be done.

so please ADMINISTRATORS: CONTACT THE PHONE'S DEVELOPERS AND TELL THEM THAT THE STOCK CAMERA APP SHOULD BE IMPROVED WITH A CORRECT
BOKEH TECHNOLOGY.

if that will not happen it would mean that the 5MP lens is fake and has absolutely no function. so IF IT IS FUNCTIONAL, there is absolutely no reason not to include
a corresponding software update!

thanks for your attention administrators. i look very much forward to your feedback and hopefully a quick update in this sense of the camera software.

StefanTh

Every comment which explains that the bokeh effect is fake will be deleted

MarcinP

007 replied at 2017-11-25 17:09
On the video "Umidigi S2 Pro disassembly after soaking in water", at 1:04, we can see the connection ...

Hi
Second camera is focusing background (depth of field) also increasing light coming to sensor. This feature is fixed that why is no adjustment and never will be because hardware can't support this. Bokeh effect is working correctly at bright condition and up to 2 metres from object.

MarcinP

In every dual camera bokeh effect is done by system.
Only Umidigi Z Pro got two cameras on back of phone which both could be used to take real pictures. One camera was used to taking coloured pictures and second for black & white pictures.
In other Umidigi devices with dual camera on back of phone one is used to take real pictures and second is also real camera unit but is not used for taking pictures,  only to support first camera with higher amount of light coming to sensor especially in darker conditions and to focus background only in certain conditions.
This setup is increasing pictures quality taken at darker conditions.  

MarcinP

Of course you can take picture in bokeh effect focused on any object you want only you need point on screen place where you want focus and adjust bokeh effect

maravilha00

MarcinP replied at 2017-11-13 06:08
Of course you can take picture in bokeh effect focused on any object you want only you need point on ...

but this is from Umidigi Z dual lens camera .... what I want to know is : has UMIDIGI S2 Pro the same feature, i.e. you chose freely where the focus point is and background blur amount? like on model Z ??

MarcinP

maravilha00 replied at 2017-11-13 06:51
but this is from Umidigi Z dual lens camera .... what I want to know is : has UMIDIGI S2 Pro the s ...

Hi
Yes I can fully confirm that camera app is exactly the same with same options and same bokeh effect.

SEBGEO67

hi
I have a Umi Crystal and I can not get good pictures with it.
I tested several applications, since the original delivered only 9mpix (for a dual sensor 13 + 5B & W mpix) it is ... light.
Is there an update planned to improve this tool?
My Umi Super took a lot more beautiful.
If there is a solution, it will be welcome
Thank you in advance.

Another thing, an update to Android 8 is planned, because of forul talks about an existing version for the Crystal?

maravilha00

MarcinP replied at 2017-11-13 15:04
Hi
Yes I can fully confirm that camera app is exactly the same with same options and same bokeh ef ...

ok thanks for confirmation.
BUT: after having had a closer look to your image showing the bokeh effect configuration on the model Z, i found it strange that the area where the focus points is kind of exactly the same round shape where image appears neat and in focus but then all around is blurred, which looks about same as the fake bokeh effect on other cameras except that it is not centered but freely placed within the image. can you actually show some sample pictures taken with that Z model or even better: with the S2 Pro ? would very much appreciate.

maravilha00

SEBGEO67 replied at 2017-11-13 18:29
hi
I have a Umi Crystal and I can not get good pictures with it.
I tested several applications, sin ...

please check the configuration of your picture size: the 13 mp are for standard picture size 4:3, while the 16:9 ratio (larger surface) results in 9 mp !

maravilha00

MarcinP replied at 2017-11-13 06:08
Of course you can take picture in bokeh effect focused on any object you want only you need point on ...

actually i forgot to ask: is camera app the same in both models Z and Z Pro ?

MarcinP

maravilha00 replied at 2017-11-15 02:36
actually i forgot to ask: is camera app the same in both models Z and Z Pro ?

Both phones contain same design camera app but of course with different features and different options etc.