Hello Gurus

Here's another thing I can't figure out. I have a video of a football match on a nice sunny day but at one point, (well, one at least) the sun was obscured by cloud so the video was under-exposed. So I had in mind to increase the exposure during that short period. I've tried several methods but none have worked as I planned. I wanted to set keyframes so that the exposure would be increased gradualy as the cloud covered the sun, and to reduce again as the cloud cleared. At first I tried to simply add the keyframes at the points where the changes are required on the Exposure Effect but this didn't work. So then I tried putting cuts at the start and end points to create a seperate clip. But no matter what I have tried the first frame of the clip gets the maximum exposure I increased it to. The result being that the clip suddenly becomes overexposed on its first frame until its last frame. The keyframes show that they are increasing at the relevant places but the change in exposure is not gradual.

All suggestions for a solution will be most welcome.

Regards

Tony

Hi Tony,

What tool did you use to modify luminosity ?

Hello Saby

Nice to hear from you again and thanks for replying. I used the Exposure control. See attachment.

I used TSITL video sample to make a test.  It's a piece of 20s of this clip. I keyframed Exposure setting 4 times. From 0 to 4s exposure is set to 0. Video is normal. Then from 4s to 10s Exposure goes from 0 to -100. Video is then completely black. Then from 10s to 16s it goes from -100 to +100. Video is now completely white. Then at 16s I reset exposure to 0. Video is normal.

Download the attached file and remove its .txt extension. Open the project and look how are created the keyframes and how they behave. It might help you understand how it works.

Thank you very much. I'll try that later and let you know how I get on.

Am I going doo-lally or something. I don't know how to download the attachment. All I can do is open it and view the code.

Don't left-click it but right-click it + "Save as" or something like that (it depends on your browser).

 

Hi Saby

Yes I must be going doo-lally. It's Save Link. Now - far be it for me to tell you how to do it but I could not open your .axp file. I tried importing, dragging and anything else I could think of; it didn't work. So perhaps you meant to save it as a Package (.axx) file which would include all the required assets of the movie. That aside, could I possibly prevail upon you to write out step-by-step instructions because I have tried other ways of doing this, - still using the Exposure setting - but without success. I must be leaving something out. I know I keep on about PS V14 but  I have used it in that version so I'm not completely new to Keyframing.

I really appreciate your assistance.

No, I simply created a .axp file, not a package.

Watch this :

https://youtu.be/I5KQ9aAB228

Thanks

Watch this.

Looks like my attachment didn't go. I'll check it out.

You can not attach video to a post....

Download from here

 

https://drive.google.com/file/d/1oozj1MU02nMuhT9I32nm9G87NNReVvDM/view?usp=sharing

I am said by Google Drive that I need to request your permission to get the file, which I did a few seconds ago but I realize that I should receive your permission on my Gmail address. I don't have access to this email inbox right now.

Would you modifiy the settings of your file to make it downloadable without your permission ?

Sorry for that. Anyone with the link shpould now be able to access it.

Ok, I got it.

What are you supposed to show in your video ? Please, explain.

If you watch the Exposure setting as the video plays you will see it increasing with the keyframes, but the video only gets darker because of the increasing cloud cover on the day. The gradual increase of exposure should help to compensate for this. I can set the whole clip with a higher exposure but that gives an unnatural appearance. The keyframe is ineffectual.

There is nothing wrong with Studio. Between keyframe #3 and keyframe #4, exposure is constant at 70. There is no gradual increase of exposure while the cloud cover is increasing. Result : at keyframe #4 (and even before it), the video is too dark.

You need to add more keyframes in between and adjust their level individually.

I didn't say there was someting wrong with Studio and I wasn't implying there was. If I set the whole clip at 70 the effect is corrected exposure in the middle, dark part but over exposed at the start and end (when sunshine is present). I don't agree with you - but I'll experiment - adding more keyframes will help. My idea was to gradually increase exposure as the cloud cover increased and reduce exposure as the cloud moved away. Set 70 should have made it much lighter during the dark period. I could set exposure to 70 over the whole clip and record it for you, if you think that would be useful.

Tony_IOM:

I didn't say there was someting wrong with Studio and I wasn't implying there was.

When I read this, I understand that something is not working in Studio :

Tony_IOM:

So I had in mind to increase the exposure during that short period. I've tried several methods but none have worked as I planned. I wanted to set keyframes so that the exposure would be increased gradualy as the cloud covered the sun, and to reduce again as the cloud cleared. At first I tried to simply add the keyframes at the points where the changes are required on the Exposure Effect but this didn't work.

Tony_IOM:

My idea was to gradually increase exposure as the cloud cover increased and reduce exposure as the cloud moved away.

Ok, but then, why is there no increase of exposure between most of the clip (from keyframe #3 to #4) ?

The natural light doesn't change significantly between those two points, so exposure doesn't need to be increased.

Do you mean that between these points light is quite constant or do you mean that it's quite the same at keyframe #3 and #4 but may vary in between ?

Let me try to be more clear:

 KF1 is on or very near to the first frame of the clip, and the Exposure is set at 0. KF2 is a few seconds later when the natural light is at its lowest (darkest)  At KF2 Exposure is set at 70. (Exagerated to show the effect.70 would, actually, be too high). At KF3 Exposure is still at 70 because the natural light is still low. At KF4 (near to or on the last frame of the clip) Exposure is set to 0 When the natural light has returned to bright. The Exposure change should be as near as possible inversly proportional to the change of natural light over the duration of the clip.

My advice remains the same. You need to use more keyframes to stick more often to the natural light variations of your footage.