Filter to enhance the quality of image

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RE: Filter to enhance the quality of image - PixLab - 05-26-2022

(05-26-2022, 07:45 AM)denzjos Wrote: @Pixlab, Every lens has barrel distortion/color fringing (depends on the quality), that's why I recommend to take RAW photos (time consuming). Then the barrel distortion/color fringing can be corrected in the software (darktable, RawTherapee, etc...). Using a lens with a fixed focus (no zoom lens) greater than 100 mm is better. On the other hand, old photo prints mostly have barrel distortion/color fringing and in this case, it is about a flat object one is trying to digitise.

Please read well my post I did say "this lens might have too much barrel distortion/color fringing...", did the way I wrote let think that lenses don't have distortion/fringing?

RE: Filter to enhance the quality of image - sallyanne - 05-26-2022

First thing I do on colour pictures is to make sure the white balance is correct. Then play with the hue slider. This time I also put the mode in LCH Hue. Then do sharpen (Unsharp Mask)

[attachment=7986]

Will have to check this thread out tomorrow night. Didn't realize the first post was from 2018

RE: Filter to enhance the quality of image - rich2005 - 05-26-2022

Quote:...Will have to check this thread out tomorrow night. Didn't realize the first post was from 2018..

I think you glanced over the OP's version of Gimp ...2.10.18 mistaken for a date That comes from a linux ubuntu distribution. Good advice but all those 'tweaks' are GEGL procedures. Not easy to incorporate into a batch procedure for the OP's 1000 images.

RE: Filter to enhance the quality of image - sallyanne - 05-26-2022

(05-26-2022, 03:51 PM)rich2005 Wrote:
Quote:...Will have to check this thread out tomorrow night. Didn't realize the first post was from 2018..

I think you glanced over the OP's version of Gimp ...2.10.18 mistaken for a date That comes from a linux ubuntu distribution. Good advice but all those 'tweaks' are GEGL procedures. Not easy to incorporate into a batch procedure for the OP's 1000 images.

It was either that or when they joined Wink

must have been tired when I posted. Um I don't use GEGL rich. Didn't even know those procedures were in there.

RE: Filter to enhance the quality of image - PixLab - 05-27-2022

(05-26-2022, 11:10 PM)sallyanne Wrote: Um I don't use GEGL rich. Didn't even know those procedures were in there.

Hi Sallyanne
All those procedure with a big white G in the menu are GEGL Big Grin

if the icon is different from the G like in the Colors menu and it's different from a "script" icon, not sure if I can say this, but roughly if you got a preview and a split screen option it's GEGL

[attachment=7987]

RE: Filter to enhance the quality of image - sallyanne - 05-27-2022

So I use 1 . (Have no use for the others)

RE: Filter to enhance the quality of image - Stephen Liu - 05-28-2022

(05-25-2022, 01:16 PM)rich2005 Wrote:
Quote:Tried again scanning film-negatives on smartphone running "Photo Negative Scanner" (software)
Smartphone - Samsung Galaxy S9+ (> 8 years) Macro Mode - 1.5

Following functions are provided on "Photo Negative Scanner"
1. Crop
2. Convert negative image to positive image
...snip....
Please advise which GIMP filter to be used to remove the green color?

How does (2) work ? Is that built into "Photo Negative Scanner" If it is obviously does not work.

Going back to previous post for a colour negative the first process in Gimp is a White Balance then a Colour -> Invert is used for the positive.

The inevitable video https://youtu.be/VXZpzuUAvLQ almost 5 minutes this time (sorry)

Some more advice on using BIMP (see earlier for a linux plugin) and adding a gmic-qt command.

Thousands to process In my opinion asking too much for one set of commands to apply universally however, those three examples.

Hi,

Thanks for your advice and video.

Have tried;
1. Scanning negatives running Kodak software
2. RAW scanning

Too many settings. It is not what I prefer.

My planning is;
1. No setting before and after scanning. Download the negative images on PC
2. Batch Post-editing - with 2/3 steps on GIMP (not too many adjusting). If possible run command-line operation.

Tried again;
1. Scan negatives on smartphone without software
2. Download the negative images on Ubuntu 20.04 PC
3. Run "mogrify - rotate" to rotate the negative images
4. Open negative images on GIMP
-> Colors -> Auto -> White Balance
again;
-> Colors > Linear Invert
5. Export positive images

The result is not bad. Please see attached photos

Comment and suggestions are welcome. Thanks.

Regards

RE: Filter to enhance the quality of image - rich2005 - 05-28-2022

Quote:Comment and suggestions are welcome. Thanks.

Trying all sorts of things, old procedures, old plugins for negative-to-positive and your negatives defeat everything. Your latest examples are small, somewhat pixelated, are you also taking larger images ?

The only other 'tweak' I can suggest is a color curves setting as:

[attachment=7996]

The three procedures are in BIMP so you could go from a folder of negatives to a folder of positives.

...however, having a beer yesterday with a friend who used to do his own color printing and even a home color enlarger had a device for analyzing each frame prior to exposing the paper. One setting for all your negatives is asking a lot.
...ImageMagick. You are using mogrify a lot Smile

That is a dangerous command, it alters images in-place. Easy to lose work...up to you.

RE: Filter to enhance the quality of image - Stephen Liu - 05-28-2022

(05-28-2022, 10:06 AM)rich2005 Wrote: Trying all sorts of things, old procedures, old plugins for negative-to-positive and your negatives defeat everything. Your latest examples are small, somewhat pixelated, are you also taking larger images ?

That is what I'm now doing.

I intentionally placed the smartphone close to the film, scanning a small image to see whether having a better quality. If working I can increase image size/resolution in batch.

Quote:The only other 'tweak' I can suggest is a color curves setting as:

Adjusting 1,000 images would take long time to complete.

Quote:The three procedures are in BIMP so you could go from a folder of negatives to a folder of positives.

I'll test it later. I'm now concentrating on scanning film negatives.

Quote:You are using mogrify a lot That is a dangerous command, it alters images in-place. Easy to lose work...up to you.

To work on 100 image files, I'll compress and archive all files first, running "gzip". I have their original copies untouched.

I'll continue to test until I find a route to proceed.

Regards

RE: Filter to enhance the quality of image - rich2005 - 05-28-2022

Quote:...I intentionally placed the smartphone close to the film, scanning a small image to see whether having a better quality. If working I can increase image size/resolution...

I think you need to do that.

For color curves

Quote:Adjusting 1,000 images would take long time to complete.

It does. Individually anything takes a long time. There is for many operation, the option to save the setting as a pre-set. Curves is no different. Worth remembering. https://i.imgur.com/oLrr9b9.mp4

Keep going, you will get there eventually.