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+--- Thread: Filter to enhance the quality of image (/Thread-Filter-to-enhance-the-quality-of-image)
RE: Filter to enhance the quality of image - Stephen Liu - 06-03-2022
(06-03-2022, 07:52 AM)PixLab Wrote:Whether you meant the light box. It is easy. I use the Tablet as light box. There are FREE software on Internet. Alternatively you can turn your old display as light box, FREE software also available on Internet(06-03-2022, 06:27 AM)Stephen Liu Wrote: Next week I'll purchase a Samsung Galaxy S22 Ultra 256G Android phone to do the job. Its camera is better.
And behind/beneath the negatives what do you use to lite them?
Regarding the scanned digital images;
I'll create digital albums to post them. Also I'll use them creating digital slideshows as well as posting them on websites.
RE: Filter to enhance the quality of image - PixLab - 06-03-2022
(06-03-2022, 10:22 AM)Stephen Liu Wrote:(06-03-2022, 07:52 AM)PixLab Wrote:(06-03-2022, 06:27 AM)Stephen Liu Wrote: Next week I'll purchase a Samsung Galaxy S22 Ultra 256G Android phone to do the job. Its camera is better.
And behind/beneath the negatives what do you use to lite them?
I'll create digital albums to post them. Also I'll use them creating digital slideshows as well as posting them on websites.
Um... You did not understand my question
what are you using to light the negatives when you are taking the picture,.
Negatives need to be lighten underneath, if you use a camera or a smartphone.
A bit like layers... At the bottom a light / light source, above your negative, and above your camera/smartphone
In other words what are you using behind the negatives to light them up or what is your backlight source?
RE: Filter to enhance the quality of image - Stephen Liu - 06-03-2022
(06-03-2022, 11:32 AM)PixLab Wrote:Please see my post #71 above.(06-03-2022, 10:22 AM)Stephen Liu Wrote:(06-03-2022, 07:52 AM)PixLab Wrote: And behind/beneath the negatives what do you use to lite them?
I'll create digital albums to post them. Also I'll use them creating digital slideshows as well as posting them on websites.
Um... You did not understand my question
what are you using to light the negatives when you are taking the picture,.
Negatives need to be lighten underneath, if you use a camera or a smartphone.
A bit like layers... At the bottom a light / light source, above your negative, and above your camera/smartphone
In other words what are you using behind the negatives to light them up or what is your light source?
On the bottom is a Tablet, the light box
The film holder, holding the negatives is above the Tablet, at about 1" distance
The smartphone is on top, shooting the negatives
RE: Filter to enhance the quality of image - PixLab - 06-03-2022
(06-03-2022, 12:18 PM)Stephen Liu Wrote: Please see my post #71 above.
On the bottom is a Tablet, the light box
The film holder, holding the negatives is above the Tablet, at about 1" distance
The smartphone is on top, shooting the negatives
Indeed I missed your post #71 (it's a quite long thread
)Tablets are cool
![[Image: thumbsup.png]](https://www.gimp-forum.net/images/icons/thumbsup.png){kind=icon}
RE: Filter to enhance the quality of image - denzjos - 06-03-2022
@Stephen Liu, the light box you use for scanning your negatives is a tablet. Make sure the light on the tablet is pure white to avoid color distortion (and color correction afterwards) :
https://www.dpmag.com/how-to/tip-of-the-week/removing-the-green-spike/
Information concerning color temperature :
https://www.vleds.com/led-color-temperature-differences
RE: Filter to enhance the quality of image - Stephen Liu - 06-04-2022
(06-03-2022, 04:16 PM)denzjos Wrote: @Stephen Liu, the light box you use for scanning your negatives is a tablet. Make sure the light on the tablet is pure white to avoid color distortion (and color correction afterwards) :
https://www.dpmag.com/how-to/tip-of-the-week/removing-the-green-spike/
Information concerning color temperature :
https://www.vleds.com/led-color-temperature-differences
Thanks for your advice.
I have LightBox (software) installed on my Tablet, long time ago.
LightBox comes from "Google Play"
Setting:
Select White color
Color Temp/White Balance slide - half (not maximum)
Brightness slide - maximum
Shall I set "Color Temp/White Balance slide" to maximum ? Or try another color? There are 7 colors for selection, Red/Blue/Yellow/White/Light Blue/Pink/Green.
I have a LED light pad, purchased long time ago. Pls refer to attached screenshot.
I never use it. The light is very poor compared to my Tablet.
Regards
RE: Filter to enhance the quality of image - denzjos - 06-04-2022
@Stephen Liu, The best tablet to use for backlight are those with an OLED screen. The normal (old) LED screens usually suffer from backlight bleed or the light is not spread evenly. OLED screens do not have this problem.
RE: Filter to enhance the quality of image - rich2005 - 06-04-2022
I think more than a few twists and turns on this subject.
Deviating from the original, Filter to enhance the quality of image ( which used a posted image) to more general images.
Upgrading to a new phone, therefore a different sensor, might change the characteristics of the image.
I would not count on a tablet to provide a suitable backlight. Might work or might not work. A diffuser might be needed.
This is from my phone (ok I know it is out of focus, not doing it again) cropped and straightened 2365x1551 px
[attachment=8048]
..and this exactly the same setup but using my camera, again cropped and straightened 3300x2361 px Same procedure negative -> positive in Gimp.
Apart from the obvious different colour balance, that matrix showing which I assume is the tablet display.
[attachment=8049]
---------
From an earlier question on renaming images. In linux I use gprename.
RE: Filter to enhance the quality of image - Stephen Liu - 06-04-2022
(06-04-2022, 08:23 AM)rich2005 Wrote: I think more than a few twists and turns on this subject.Hi rich,
Deviating from the original, Filter to enhance the quality of image ( which used a posted image) to more general images.
Upgrading to a new phone, therefore a different sensor, might change the characteristics of the image.
I would not count on a tablet to provide a suitable backlight. Might work or might not work. A diffuser might be needed.
This is from my phone (ok I know it is out of focus, not doing it again) cropped and straightened 2365x1551 px
..and this exactly the same setup but using my camera, again cropped and straightened 3300x2361 px Same procedure negative -> positive in Gimp.
Apart from the obvious different colour balance, that matrix showing which I assume is the tablet display.
---------
From an earlier question on renaming images. In linux I use gprename.
I attach 2 photos and 1 scanned negative here for your comment.
Smartphone - Samsung Galaxy S9+
Macro - 2x
1)
Photos - shoot at normal room light. No post-editing
2)
Scanned negative
Night source - Tablet
"Color Temp/White Balance slide" turned to maximum value
Crop on GIMP
Colors -> Auto -> White Balance
Colors -> Linear Invert
No further post-editing
Their quality is not bad
Regards
(06-04-2022, 06:41 AM)denzjos Wrote: @Stephen Liu, The best tablet to use for backlight are those with an OLED screen. The normal (old) LED screens usually suffer from backlight bleed or the light is not spread evenly. OLED screens do not have this problem.Thanks for your advice.
I won't upgrade my Tablet. I don't need a new Tablet and my old Tablet is just resting on shelves.
I'm considering to purchase a light box or a light pad.
Light box vs light pad
Which of them I should buy? Thanks
Regards
RE: Filter to enhance the quality of image - rich2005 - 06-04-2022
Keep going - only 999 more to go