Arguments for Digital Zoom to be better are:
a) Fuji actually have 12M pixels and interpolating in camera before committing to 6MB jpg could give better result.
b) With the proper framing enabled by the digital zoom, the metering would be more accurate and will result in a better picture.
The pictures taken at the various zoom are shown on the left. For comparison purpose, a Panasonic FZ3 (3 M) with 420mm zoom is included.The subject for comparison purpose is the wooden bird. The pictures are cropped to have just the bird. For the 3x optical zoom, the cropped image is upsized using bi-cubic at 10% step until the image is roughly 640x480. The mid digital zoom picture (282mm) is cropped and not re-sized at all. The max digital zoom picture (695mm) is down-sized using Bi-linear(2pass) in 10% step till image is about 640x480. The Pana FZ3 shot is cropped and shown as it is without any resizing. The Pana's image is slightly more yellowish compared to the actual Bird color. F30's bird greyish color is more accuate.
I have set the shutter speed to be roughly an inverse of the focal distance to compensate for the camera shake for zoom shot. At higher zoom, the effect of camera-shake is strong. I have to replace the 1/320 shot which shows some blur due to camera shake with a 1/250 one which gives a sharper image. I guessed I must be holding the 1/250 shot better than the 1/320 one.What can we conclude ? I think the 695mm picture is worse, and may be the the 282mm is very very slightly better than the sized-up 113mm shot. But they could not compared with the FZ3 shot at all.
The recommended rule might be stay with optical zoom. The digital zoom needs one to have higher shutter speed to compensate for camera-shake that reduces the light input. Mid range digital zoom perhaps can be used when the lighting is adequate.
No comments:
Post a Comment