Continuing Darktable Review

Vernon D Rainwater

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Testing with Darktable (I assume) regarding Prospective Correction. However,I have not found how to change (straighten) ONLY the left side of example image. Below are the steps I use within Pgotoshop to make this type of change and would like to make these changes while in Darktable RAW processing procedure.

Please excuse the "Modified Image" that is changed since it has people in the picture and do not desire to post with them present.

Also, please; NO comments regarding the blurred out part.

Select all > Edit > Transform > Distort

Pull lower lwft corner to left until door facings straight Verticel plus no change in lower boundary line of image.

Apply

Save image with different Name.



Distorted Image Example:



95c8052dec9a4c7d96e1cd07a66b4f9f.jpg



Below is corrected image corrected using Photoshop:





e03f5f62d9ab41b4ac5cd97b9fe1aae0.jpg





--
Vernon...
 
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Testing with Darktable (I assume) regarding Prospective Correction. However,I have not found how to change (straighten) ONLY the left side of example image.
Liquify?

I've never done it, but I believe that it's intended for just this kind of thing.

GIMP has Warp, which is similar.
 
Did you try the keystone correction in the crop and rotate module?
 
Did you try the keystone correction in the crop and rotate module?
No I have not and will go look at that now. I have been "googleing" (spell) trying to find something that may be applicable for Darktable.

EDIT to add:

Thanks for the suggestion: I did a quick try to use that area for desired results and it apparently works (operates) by changing the angle of the entire image and as originally explained, that is not what is needed.

--
Vernon...
 
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Testing with Darktable (I assume) regarding Prospective Correction. However,I have not found how to change (straighten) ONLY the left side of example image.
Liquify?

I've never done it, but I believe that it's intended for just this kind of thing.

GIMP has Warp, which is similar.
I viewed all referenced by Google but didn't find anything that appears to be applicable.
 
Did you try the keystone correction in the crop and rotate module?
No I have not and will go look at that now. I have been "googleing" (spell) trying to find something that may be applicable for Darktable.

EDIT to add:

Thanks for the suggestion: I did a quick try to use that area for desired results and it apparently works (operates) by changing the angle of the entire image and as originally explained, that is not what is needed.
Apologies for my earlier reply. I misread your original post. Actually there is an interesting YouTube video about Liquify, where darktable is used to enlarge a butt and reduce a nose, but you wanted straight-line correction.

I used it in this edit posted to the Fuji X forum, to prevent the building from looking like it would fall over.

https://www.dpreview.com/forums/post/62274338
 
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Did you try the keystone correction in the crop and rotate module?
No I have not and will go look at that now. I have been "googleing" (spell) trying to find something that may be applicable for Darktable.

EDIT to add:

Thanks for the suggestion: I did a quick try to use that area for desired results and it apparently works (operates) by changing the angle of the entire image and as originally explained, that is not what is needed.
Apologies for my earlier reply. I misread your original post. Actually there is an interesting YouTube video about Liquify, where darktable is used to enlarge a butt and reduce a nose, but you wanted straight-line correction.

I used it in this edit posted to the Fuji X forum, to prevent the building from looking like it would fall over.

https://www.dpreview.com/forums/post/62274338
No apologies necessary. When trying to learn, I am pleased to receive all help.
 
Did you try the keystone correction in the crop and rotate module?
No I have not and will go look at that now. I have been "googleing" (spell) trying to find something that may be applicable for Darktable.

EDIT to add:

Thanks for the suggestion: I did a quick try to use that area for desired results and it apparently works (operates) by changing the angle of the entire image and as originally explained, that is not what is needed.
It is hard to tell how you used it. Did you use the vertical correction? What do you mean by "changing the angel of the entire image"?
 
Did you try the keystone correction in the crop and rotate module?
No I have not and will go look at that now. I have been "googleing" (spell) trying to find something that may be applicable for Darktable.

EDIT to add:

Thanks for the suggestion: I did a quick try to use that area for desired results and it apparently works (operates) by changing the angle of the entire image and as originally explained, that is not what is needed.
It is hard to tell how you used it. Did you use the vertical correction? What do you mean by "changing the angel of the entire image"?
Yes, I tried the vertical correction. The entire image was shifting (to the right/left) depending on the selected choice. What is needed (as per example posted image) is for the bottom left to be shifted to the left which allows the vertical door facings to become vertically straight.
 
Yes, I tried the vertical correction. The entire image was shifting (to the right/left) depending on the selected choice. What is needed (as per example posted image) is for the bottom left to be shifted to the left which allows the vertical door facings to become vertically straight.
Try crop and rotate > keystone (left side only). Here is a video about it, with the correction ending about 3 minutes in.

 
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Yes, I tried the vertical correction. The entire image was shifting (to the right/left) depending on the selected choice. What is needed (as per example posted image) is for the bottom left to be shifted to the left which allows the vertical door facings to become vertically straight.
Try crop and rotate > keystone (left side only). Here is a video about it, with the correction ending about 3 minutes in.

I attempted to view the video but (as with all YouTube Videos) I am having problems with the Menu items on screen being so VERY small that I am unable to follow the menu selections Being made. I of course can see the usage of the two vertical "guide lines" that he is using to change to effect the straightening of the video image but have no idea of selection(s) made to be able to use them. Are you able to determine on your Monitor the menu selection he is using.

Later, I will change video connections that allows viewing the video(s) on our 52 inch TV which of course has both video and sound provisions. However, there is no sound on the computer when viewing on the TV and definitely is not ideal (with the TV being in a different room) -- other than at least I can read the menus that are too small on the Computer Monitors.

I have dual Monitors but have not found a way to extend YouTube Videos over to 2nd monitor to make the video viewing wider.
 
Try crop and rotate > keystone (left side only). Here is a video about it, with the correction ending about 3 minutes in.

I attempted to view the video but (as with all YouTube Videos) I am having problems with the Menu items on screen being so VERY small that I am unable to follow the menu selections Being made. I of course can see the usage of the two vertical "guide lines" that he is using to change to effect the straightening of the video image but have no idea of selection(s) made to be able to use them. Are you able to determine on your Monitor the menu selection he is using.

Later, I will change video connections that allows viewing the video(s) on our 52 inch TV which of course has both video and sound provisions. However, there is no sound on the computer when viewing on the TV and definitely is not ideal (with the TV being in a different room) -- other than at least I can read the menus that are too small on the Computer Monitors.

I have dual Monitors but have not found a way to extend YouTube Videos over to 2nd monitor to make the video viewing wider.
Well, the summary is that after selecting keystone, you move the left side to line up with your door frame, then click OK in the center of screen.
 
Try crop and rotate > keystone (left side only). Here is a video about it, with the correction ending about 3 minutes in.

I attempted to view the video but (as with all YouTube Videos) I am having problems with the Menu items on screen being so VERY small that I am unable to follow the menu selections Being made. I of course can see the usage of the two vertical "guide lines" that he is using to change to effect the straightening of the video image but have no idea of selection(s) made to be able to use them. Are you able to determine on your Monitor the menu selection he is using.

Later, I will change video connections that allows viewing the video(s) on our 52 inch TV which of course has both video and sound provisions. However, there is no sound on the computer when viewing on the TV and definitely is not ideal (with the TV being in a different room) -- other than at least I can read the menus that are too small on the Computer Monitors.

I have dual Monitors but have not found a way to extend YouTube Videos over to 2nd monitor to make the video viewing wider.
Well, the summary is that after selecting keystone, you move the left side to line up with your door frame, then click OK in the center of screen.
Many thanks, You have definitely identified the proper functions within Darktable to use for my OP inquiry.

After getting to view the video on the large screen TV, I could see (there were no other menu selections being made) and how he was moving the Vertical alignment lines (probably not the correct name for these) to be as close as possible to the position (angle) of the "left and right)" vertical position of the building, then; clicking the center (marker) to execute the change. Then check the alignment again and correct using same procedure to be more accurate. He was working with both left and right alignment and (of course) I will be using only the LEFT, for my tests.

I switched back (from TV connection) to using my dual monitors and made the (Left) adjustment for a couple of my images (including slight correction of left bar angle) and it did well for both images.

I looked but did not find an option to NOT crop the image. However, the cropping is not a "problem" for what I would be using this for. I just don't like vertical "leaning" objects which should be straight-up. However, this does change the Pixel dimensions so I will have to be cautious when needing to Overlay images for other corrections and/or adjustments during additional Post Processing .

--
Vernon...
 
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How to sharpen a group of images, using the same USM settings for each image. My first selected image has 5 items in History (see below) with the last being my USM (Test) setting of 3.00 1.00 0. Using the Select menu for the first image I hold down Shift and click the last image in the Group which selects the 10 images for this group. However, in the menu to select History, I click Copy and the screen displays only the bottom 3 items but does not show all the items in the History Stack. Example of Stack below:

b977d91c8b264fb2b1fbe74b1619bbc0.jpg

This is from the first image in the group and I want to select ONLY item 4 Sharpen to Copy then paste to the other images in the selected group.

However, only the first 3 items appear in the small screen where I need to copy only the top # 4 item. Need help to accomplish. I could not find any applicable help items using Google.

--
Vernon...
 
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Many thanks, You have definitely identified the proper functions within Darktable to use for my OP inquiry.

After getting to view the video on the large screen TV, I could see (there were no other menu selections being made) and how he was moving the Vertical alignment lines (probably not the correct name for these) to be as close as possible to the position (angle) of the "left and right)" vertical position of the building, then; clicking the center (marker) to execute the change. Then check the alignment again and correct using same procedure to be more accurate. He was working with both left and right alignment and (of course) I will be using only the LEFT, for my tests.

I switched back (from TV connection) to using my dual monitors and made the (Left) adjustment for a couple of my images (including slight correction of left bar angle) and it did well for both images.

I looked but did not find an option to NOT crop the image. However, the cropping is not a "problem" for what I would be using this for. I just don't like vertical "leaning" objects which should be straight-up. However, this does change the Pixel dimensions so I will have to be cautious when needing to Overlay images for other corrections and/or adjustments during additional Post Processing .
One of the options in the Crop & Rotate tool is automatic crop = no (defaults to yes).

I would not recommend this, because then you end up with black triangles at the corner(s).

Sorry, I don't use sharpening much so I can't answer your later question. Probably future darktable versions will get sharpening tools superior to Unsharp Mask, which is halo city.
 
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Many thanks, You have definitely identified the proper functions within Darktable to use for my OP inquiry.

After getting to view the video on the large screen TV, I could see (there were no other menu selections being made) and how he was moving the Vertical alignment lines (probably not the correct name for these) to be as close as possible to the position (angle) of the "left and right)" vertical position of the building, then; clicking the center (marker) to execute the change. Then check the alignment again and correct using same procedure to be more accurate. He was working with both left and right alignment and (of course) I will be using only the LEFT, for my tests.

I switched back (from TV connection) to using my dual monitors and made the (Left) adjustment for a couple of my images (including slight correction of left bar angle) and it did well for both images.

I looked but did not find an option to NOT crop the image. However, the cropping is not a "problem" for what I would be using this for. I just don't like vertical "leaning" objects which should be straight-up. However, this does change the Pixel dimensions so I will have to be cautious when needing to Overlay images for other corrections and/or adjustments during additional Post Processing .
One of the options in the Crop & Rotate tool is automatic crop = no (defaults to yes).

I would not recommend this, because then you end up with black triangles at the corner(s).

Sorry, I don't use sharpening much so I can't answer your later question. Probably future darktable versions will get sharpening tools superior to Unsharp Mask, which is halo city.
In Photoshop post processing relating to USM, I use Actions to apply to all (or groups) of images which is somewhat faster and easy. Basically, I am attempting to find the equivalent within Darktable as how Actions are used in Photoshop. I have many Photoshop Actions that I developed over the years that do a good job and saves me a lot of work and time.

I believe the last option in USM sharpening (Threshold) is the primary part of USM that can sometimes provide NOT good results. That is why I (almost always) set this to 0 (zero) and I don't have any problems with halo's. However, I prefer to apply USM to Shadows (darker areas) somewhat different than what I use for the overall image.

I have not finalized the use of Mask(s) to be successful for selecting Shadows -- or Highlights then convert to apply to shadows. I will practice some more with this as time permits. Details regarding this was discussed in a previous thread

--
Vernon...
 
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Try crop and rotate > keystone (left side only). Here is a video about it, with the correction ending about 3 minutes in.

I attempted to view the video but (as with all YouTube Videos) I am having problems with the Menu items on screen being so VERY small that I am unable to follow the menu selections Being made. I of course can see the usage of the two vertical "guide lines" that he is using to change to effect the straightening of the video image but have no idea of selection(s) made to be able to use them. Are you able to determine on your Monitor the menu selection he is using.

Later, I will change video connections that allows viewing the video(s) on our 52 inch TV which of course has both video and sound provisions. However, there is no sound on the computer when viewing on the TV and definitely is not ideal (with the TV being in a different room) -- other than at least I can read the menus that are too small on the Computer Monitors.

I have dual Monitors but have not found a way to extend YouTube Videos over to 2nd monitor to make the video viewing wider.
Well, the summary is that after selecting keystone, you move the left side to line up with your door frame, then click OK in the center of screen.
Many thanks, You have definitely identified the proper functions within Darktable to use for my OP inquiry.
This was exactly the "function" I referred to in my first answer. Which one did you actually try then?
After getting to view the video on the large screen TV, I could see (there were no other menu selections being made) and how he was moving the Vertical alignment lines (probably not the correct name for these) to be as close as possible to the position (angle) of the "left and right)" vertical position of the building, then; clicking the center (marker) to execute the change. Then check the alignment again and correct using same procedure to be more accurate. He was working with both left and right alignment and (of course) I will be using only the LEFT, for my tests.

I switched back (from TV connection) to using my dual monitors and made the (Left) adjustment for a couple of my images (including slight correction of left bar angle) and it did well for both images.

I looked but did not find an option to NOT crop the image. However, the cropping is not a "problem" for what I would be using this for. I just don't like vertical "leaning" objects which should be straight-up. However, this does change the Pixel dimensions so I will have to be cautious when needing to Overlay images for other corrections and/or adjustments during additional Post Processing .
 
Try crop and rotate > keystone (left side only). Here is a video about it, with the correction ending about 3 minutes in.

I attempted to view the video but (as with all YouTube Videos) I am having problems with the Menu items on screen being so VERY small that I am unable to follow the menu selections Being made. I of course can see the usage of the two vertical "guide lines" that he is using to change to effect the straightening of the video image but have no idea of selection(s) made to be able to use them. Are you able to determine on your Monitor the menu selection he is using.

Later, I will change video connections that allows viewing the video(s) on our 52 inch TV which of course has both video and sound provisions. However, there is no sound on the computer when viewing on the TV and definitely is not ideal (with the TV being in a different room) -- other than at least I can read the menus that are too small on the Computer Monitors.

I have dual Monitors but have not found a way to extend YouTube Videos over to 2nd monitor to make the video viewing wider.
Well, the summary is that after selecting keystone, you move the left side to line up with your door frame, then click OK in the center of screen.
Many thanks, You have definitely identified the proper functions within Darktable to use for my OP inquiry.
This was exactly the "function" I referred to in my first answer. Which one did you actually try then?
After getting to view the video on the large screen TV, I could see (there were no other menu selections being made) and how he was moving the Vertical alignment lines (probably not the correct name for these) to be as close as possible to the position (angle) of the "left and right)" vertical position of the building, then; clicking the center (marker) to execute the change. Then check the alignment again and correct using same procedure to be more accurate. He was working with both left and right alignment and (of course) I will be using only the LEFT, for my tests.

I switched back (from TV connection) to using my dual monitors and made the (Left) adjustment for a couple of my images (including slight correction of left bar angle) and it did well for both images.

I looked but did not find an option to NOT crop the image. However, the cropping is not a "problem" for what I would be using this for. I just don't like vertical "leaning" objects which should be straight-up. However, this does change the Pixel dimensions so I will have to be cautious when needing to Overlay images for other corrections and/or adjustments during additional Post Processing .
You are correct regarding your original suggestion, however; because of my lack of experience with Darktable -- obviously I was not able to determine how to use the "Crop and Rotate Keystone" function for the desired results.

The below added helpful details posted at: https://www.dpreview.com/forums/post/62303051

including the video link; is the part that provided information for "how to properly use the function".

Try crop and rotate > keystone (left side only). Here is a video about it, with the correction ending about 3 minutes in.


Also, Please refer to my following previous post: https://www.dpreview.com/forums/post/62304268

which explains what I did to be able to find out how to use the function by switching to our 52 inch TV in order to be able to see the various menu selections (and mouse clicks) being made in the above mentioned Video.

Hopefully, this will answer details in your last post.

My Regards -- Vernon...
 
When raw (CR2) image files are Imported into Darktable the History for each image has the same information. 0-Original 1- Orientation 2-Sharpen 3-Base Curve. I have no idea the values (settings) used in each of the above (especially Sharpening and Base Curve). I expect Orientation is acquired from the image information part of each image.

I expect this comes from a "Default file" for which I have not found including Google searches. Where can I find this information in any of the Darktable Files, including the Manual.

I would like to know how to change these Parameters plus possibly to substitute a different set of items (as Default settings) to use in place of the present (Default) settings.

Edit to add:

Also, I could not find a way to discard the mentioned items from History. Those added by the user are removable.

--
Vernon...
 
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When raw (CR2) image files are Imported into Darktable the History for each image has the same information. 0-Original 1- Orientation 2-Sharpen 3-Base Curve. I have no idea the values (settings) used in each of the above (especially Sharpening and Base Curve). I expect Orientation is acquired from the image information part of each image.

I expect this comes from a "Default file" for which I have not found including Google searches. Where can I find this information in any of the Darktable Files, including the Manual.

I would like to know how to change these Parameters plus possibly to substitute a different set of items (as Default settings) to use in place of the present (Default) settings.
I think what you are looking for are the Module Presets?


Or maybe the History Stack?


It seems to me that Darktable attempts to create a similar history stack as the one you used previously, to streamline your workflow. When you have a working workflow, you can create your own presets that follow the same module flow automatically.
Edit to add:

Also, I could not find a way to discard the mentioned items from History. Those added by the user are removable.
See the History Stack op. cit.
 

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