Quote:
Originally Posted by Ricci @Clevermax :
That looks very interesting. If I understand correctly, all the shots must have the same exposure, but varying shutter speed to compensate for ISO change while keeping aperture constant ? This technique won't work well for shots where the scene changes ( astrophotography , low light in general ) , or opportunistic shots that you cannot recompose exactly.
I suppose pixel binning might work better for that , though I haven't seen its effectiveness in reducing noise. Cameras with high pixel count like the D800 could use this technique, hope Nikon incorporates that in future releases. |
All shots are taken at f/8, so the shutter speed was varied. For ISO800 - 1/50s, for ISO3200 - 1/250s and so on.
This feature is useful when you want to take a steady shot of a low light scene without much people movement or any relative motion within the scene. For example, you want to photograph a building in low light without tripod, all you have to do is to select an ISO which will give you a good shutter speed, click the scene hand held. The algorithm is smart enough to cancel out image shifts across the shots and give you a final steady image with low noise. I have noticed that it even takes care of smaller movements of people, hands etc across the shots, as they won't appear from all the images in the merged one.
Pixel binning is better in the sense that it requires a single shot and the averaging takes place by combining adjacent pixels within the single image, hence resulting in a much lower resolution final image than what the sensor is capable of. In stacked mode, this is not the case, the resolution of the final image is same as the resolution of the individual shots. In my case, I get a 16MP image as the result from my 16MP sensor.
Nokia's 41MP camera phone has pixel binning and they recommend users to click take images at 5MP or so - pixel binning at work
Quote:
Originally Posted by Ricci That looks very interesting. If I understand correctly, all the shots must have the same exposure, but varying shutter speed to compensate for ISO change while keeping aperture constant ? This technique won't work well for shots where the scene changes ( astrophotography , low light in general ) , or opportunistic shots that you cannot recompose exactly. |
I think there is a misunderstanding - so clarifying it more precisely.
Let's talk about the stacked ISO shot at IS0800. It was taken at f/8, 1/50s and stacked ISO800. This means, the camera took
6 shots with exactly the same settings as given above, and then averaged them to produce the final stacked ISO800 image. Similarly, for the ISO3200 image I gave, the settings were 1/250s, f/8 and IS3200 - the camera took 6 shots one by one with this same settings and merged them. This happens in a single click and since mine is an SLT, it has very good fps to take 6 shots quicker than similar DSLRs. So in the post above, the picture on top is NOT a resultant image of all the shots at various ISOs given below. Each of them are different stacked shots.
I gave samples at all ISOs just to give an idea about the amount of noise in those ISOs. Basically, user has the freedom to click stacked shots from ISO100 to ISO25600.
MODS: Please merge this post with the above post of mine. I added this after the time window for editing the previous one.