ingoandfloyd
Active member
Just try the extended teleconversion mode in 1200 asa and i have to say the pitchure is to way to noisy, iam doing anything wrong?
extended teleconversion mode
- Thread starter ingoandfloyd
- Start date
Why? You haven't changed the size of each pixel or affected the lens. It still let's the same amount of light in.
Now the fact that you are not scaling the full sensor image might mean you loose some of the light do to the reduced sensor size. However, it doesn't appear to affect exposure at all so I don't think it really affects the noise either.
farfromsubtle
Well-known member
You're not doing anything wrong. In all of my shooting, I have found Ex Tele mode to be noisier and more susceptible to banding.
JamesRitson
Member
Extended tele mode is great, but it can be incredibly noisy, and as noted above, can produce blue banding especially when shooting with tungsten lights. Fortunately, the blue banding is (really) easy to take care of with some temporal smoothing.
My theory on the amount of noise is simply that in Tele-Ex mode the camera is taking an unprocessed 1080p crop (so about 2 megapixels) and compressing it. In regular shooting mode, the entire sensor image is (hopefully) down-sampled gracefully and so the noise becomes much finer and less obtrusive. Downsampling's a fairly common method of reducing noise and improving compressibility.
What annoys me about the ETC noise is that it's really hard to clean up without destroying the overall picture quality. A fair amount of it is high frequency noise, but there's also mosquito noise resulting from the compression.
Another point to note is that ETC will show up shortcomings on a lens much more - softness, chromatic aberration, dust spots, etc.
Having said all that, though, it's still a fantastic little feature, especially since it's on a consumer product. Just don't expect to be able to push the ISO and get a very clean image!
My theory on the amount of noise is simply that in Tele-Ex mode the camera is taking an unprocessed 1080p crop (so about 2 megapixels) and compressing it. In regular shooting mode, the entire sensor image is (hopefully) down-sampled gracefully and so the noise becomes much finer and less obtrusive. Downsampling's a fairly common method of reducing noise and improving compressibility.
What annoys me about the ETC noise is that it's really hard to clean up without destroying the overall picture quality. A fair amount of it is high frequency noise, but there's also mosquito noise resulting from the compression.
Another point to note is that ETC will show up shortcomings on a lens much more - softness, chromatic aberration, dust spots, etc.
Having said all that, though, it's still a fantastic little feature, especially since it's on a consumer product. Just don't expect to be able to push the ISO and get a very clean image!
Peter J. DeCrescenzo
Veteran
But, depending on the scene, the GH2's wonderful ETC feature can produce nice-looking video with little "objectionable" noise. In other words, the noise is there, but it doesn't necessarily ruin the shot.
Remember, with ETC there are pluses & minuses. ETC's tele effect is awesome, its lack of aliasing & moire is awesome, assigning it to a function button is awesome, and oh, yeah, it introduces some noise. So, on balance it's just slightly less than awesome.
This scene was shot with ETC, an old Nikon 55mm f1.2 lens, at ISO 1250. The camera-original 1080p24 "24H" .MTS file can be downloaded from the Vimeo page. Cheers.
http://vimeo.com/18001992
Note: If I was shooting this scene again, I might try shooting it at ISO 1600 (and stop-down the lens), and set NR at 0 or -1 or -2, to see if that produced even cleaner results. YMMV.
Remember, with ETC there are pluses & minuses. ETC's tele effect is awesome, its lack of aliasing & moire is awesome, assigning it to a function button is awesome, and oh, yeah, it introduces some noise. So, on balance it's just slightly less than awesome.
This scene was shot with ETC, an old Nikon 55mm f1.2 lens, at ISO 1250. The camera-original 1080p24 "24H" .MTS file can be downloaded from the Vimeo page. Cheers.
http://vimeo.com/18001992
Note: If I was shooting this scene again, I might try shooting it at ISO 1600 (and stop-down the lens), and set NR at 0 or -1 or -2, to see if that produced even cleaner results. YMMV.