sf
Veteran
In case anyone is interested :
This is my secret method for cancelling noise *in certain circumstances*. It works marvelously.
This only works on tripod shots, where you can take at least three shots of exactly the same picture. That means, if you are shooting a night landscape, you must expose at least three frames without moving the camera at all. Simple enough. It works really well for evening landscapes, nightscapes, and stiff life shots. Of course, you'd have to be shooting with a digital or an automatic advancing camera (or just be really good at not moving the camera when you advance).
Best thing about it, is that it works with images scanned from film too. You can shoot three copies of something in low light with your Leica, and apply the following method to cancelling out the noise:
For best results, have as many copies of the image as possible - that means actual shots, you can't just make copies of the same shot on your computer because they would all have the same noise patterns and the process would not work. And always use either a remote shutter release or a cable. Never try to do this by tripping the shutter with your finger - any movement will ruin things.
Using photoshop:
1. Open the images, all at once, in the workspace.
2. Call one image the foundation image (just so you know which one will be left unchanged)
3. Copy one of the images and paste it over the foundation.
4. Using the "Window" menu on the top, select the "Layers" to show the layers box in the workspace.
5. Set the opacity of the image (that was put on top of the foundation image) to 40% or so.
Repeat steps 3,4, and 5 for all the shots except the foundation (of course).
When finished, flatten the image.
Best in shots without moving objects. Shots of the moon with your telephoto would work. Or still life shots of the camera and coffee.
The idea is that you have piled a bunch of shots on top of eachother and have set their opacities to translucent, therefore allowing their noisiness to combine. The effect is that the noise is cancelled out (or maybe just blurred out). Either way, I think it works really well. And it does not forfeit any clarity at all. I think it even bolsters the color and tonality too. I will do this next time I go out and shoot a post-sunset scene here in LA, to get rid of the terrible noise in the dark areas of my frame. Of course, the only trouble is, moving objects will become an issue, but you can use Photoshop to make up for that too.
See my samples please. The first is a full size screenshot with one original on the left, and the layered, noiseless product on the right. The first is BIG, so viewers without high speed access would do better with the nomonoise2 sample.
The images are all unedited except for their opacities and being layered together.
Thanks
This is my secret method for cancelling noise *in certain circumstances*. It works marvelously.
This only works on tripod shots, where you can take at least three shots of exactly the same picture. That means, if you are shooting a night landscape, you must expose at least three frames without moving the camera at all. Simple enough. It works really well for evening landscapes, nightscapes, and stiff life shots. Of course, you'd have to be shooting with a digital or an automatic advancing camera (or just be really good at not moving the camera when you advance).
Best thing about it, is that it works with images scanned from film too. You can shoot three copies of something in low light with your Leica, and apply the following method to cancelling out the noise:
For best results, have as many copies of the image as possible - that means actual shots, you can't just make copies of the same shot on your computer because they would all have the same noise patterns and the process would not work. And always use either a remote shutter release or a cable. Never try to do this by tripping the shutter with your finger - any movement will ruin things.
Using photoshop:
1. Open the images, all at once, in the workspace.
2. Call one image the foundation image (just so you know which one will be left unchanged)
3. Copy one of the images and paste it over the foundation.
4. Using the "Window" menu on the top, select the "Layers" to show the layers box in the workspace.
5. Set the opacity of the image (that was put on top of the foundation image) to 40% or so.
Repeat steps 3,4, and 5 for all the shots except the foundation (of course).
When finished, flatten the image.
Best in shots without moving objects. Shots of the moon with your telephoto would work. Or still life shots of the camera and coffee.
The idea is that you have piled a bunch of shots on top of eachother and have set their opacities to translucent, therefore allowing their noisiness to combine. The effect is that the noise is cancelled out (or maybe just blurred out). Either way, I think it works really well. And it does not forfeit any clarity at all. I think it even bolsters the color and tonality too. I will do this next time I go out and shoot a post-sunset scene here in LA, to get rid of the terrible noise in the dark areas of my frame. Of course, the only trouble is, moving objects will become an issue, but you can use Photoshop to make up for that too.
See my samples please. The first is a full size screenshot with one original on the left, and the layered, noiseless product on the right. The first is BIG, so viewers without high speed access would do better with the nomonoise2 sample.
The images are all unedited except for their opacities and being layered together.
Thanks
Last edited:
K
Kin Lau
Guest
Also known as "stacking"... used by many amateur astronomers also. Thanks for doing the write up.
sf
Veteran
sweet
sweet
Yeah, I figured it would be a good tool for astrophotography. I hear that they use it to increase the contrast and the intensities of stars. I rather used it to remove noise. It doesn't take very long to do it, and it does the job more effectively that any other method I have come across.
sweet
Yeah, I figured it would be a good tool for astrophotography. I hear that they use it to increase the contrast and the intensities of stars. I rather used it to remove noise. It doesn't take very long to do it, and it does the job more effectively that any other method I have come across.
Biber
Established
You might want to have a look at this program too:
http://www.tawbaware.com/imgstack.htm
I've never had any real use for it myself but I've heard very good reports about it.
http://www.tawbaware.com/imgstack.htm
I've never had any real use for it myself but I've heard very good reports about it.