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Occasional Contributor
Posts: 11
Registered: ‎05-18-2020

Photo has bright and darker on an aerial photo question

For those that work in photogrammetry world, my question is how can I correct this old aerial photo that needed to be correct from a darker and bright black and white. I would have like to have both the same one black and white in either dark or bright.

 

I am not sure how to fix this black and white a easier way to do it ?

 

Is it possible for me to correct it from the right side into the left side to make the same one?

 

Here is the screenshot

 

 dXBVD.png

 

They are not mosaic. it is a digital file that i got from a contractor that scanned it from the film that was flown from 1938 on our national forest. It does not have coordinate system. 

 

Does anyone here have any suggest how to fix this ?

This is my second profile.
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Frequent Contributor
Posts: 112
Registered: ‎01-20-2016

Re: Photo has bright and darker on an aerial photo question

Hi Robert,

 

I would create an aoi which contains the bright area and use it to manually adjust the brightness until it is adapted to the right portion of the image.

 

There is a Brighness Adjustment tool especially for SAR imagery, but that might not work on optical data. I am not sure about that. You find it on the Raster tab > Radar Toolbox > Utilities

 

Hope that helps,

Ruth

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Occasional Contributor
Posts: 11
Registered: ‎05-18-2020

Re: Photo has bright and darker on an aerial photo question

Thank you, Ruth

 

So when I do that , how do I save it when I am satisfied with it ?

This is my second profile.
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Frequent Contributor
Posts: 112
Registered: ‎01-20-2016

Re: Photo has bright and darker on an aerial photo question

[ Edited ]

Hi Robert,

 

I have to admit that I was not very successful applying the aoi.

It might be easier in your case to split the image into two parts and adapt one half of it as a whole.

 

Open the image half in the viewer. Apply any brightness or contrast setting. Save it to the image while clicking on the disk symbol. Clear the view. Open the image again (disable No stretch in the options) to check whether the desired LUT (look up table) stretch was saved to the image.

 

Save the LUT into the image using the function LUT Stretch on the Raster Tab > Resolution > Radiometric

Open the saved image in a viewer without applying any stretch to verify that the stretch is now inside the image.

 

Mosaic both image halves.

 

It's kind of tricky, but it should be feasible.

 

Ruth

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Occasional Contributor
Posts: 11
Registered: ‎05-18-2020

Re: Photo has bright and darker on an aerial photo question

Thank you. I have unsuccessful save the file using save as on the file when I made the change from breakpoint. I got it sort of it worked but it would not save it at all...

 

I tried everything until my modem at home died.  I had to wait for a few days for the new modem to arrive . I just saw your message now

 

That is what I had my mind is to split the two and the bright one get it to fix it.

 

 

This is my second profile.
Highlighted
Occasional Contributor
Posts: 11
Registered: ‎05-18-2020

Re: Photo has bright and darker on an aerial photo question

Hello,

 

Here are the results that I put together when I first post my question...

 

So after the first time I tried to use the breakpoint with the aoi to apply the matching histogram and got no luck...

 

Then after Ruth suggest me to split them into separate and do mosaic later...

 

Well, I did that what Ruth was suggesting AND I found out that the bright image to the left is an actually 16 unsigned bit.  So I then use the tool Rescale to get it back to 8 before I could mosaci both of them .

 

So what do you think ?  and your feedback ?

 

Here is the screenshot 

 

 

 

 

This is my second profile.
Highlighted
Occasional Contributor
Posts: 11
Registered: ‎05-18-2020

Re: Photo has bright and darker on an aerial photo question

[ Edited ]

The same thing but when I tried to do mosaic and it came the darker stripe .

 

The post mosaic had strips in it...  

 

THis one I had to split the image separate and rescale the 16 bit to 8 bit and then mosaic again and came with that line you see....

 

Suggest to fix it ?

 

 

Here is the screen shot before and after 

 

This is my second profile.
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Frequent Contributor
Posts: 112
Registered: ‎01-20-2016

Re: Photo has bright and darker on an aerial photo question

[ Edited ]

The post_image.png looks good to me!