photomachine said:It's changing from 1.5" to APS-C not from 1"
correct. But 1.5" to APS-C is still a rather significant change in diameter of imaging circle.
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photomachine said:It's changing from 1.5" to APS-C not from 1"
Rocky said:This is a G series camera. I think one of the requirement is "coat pocketable" and versatile. Therefore long Super zoom is out of question, fast medium zoom is out of question, may be even fast short zoom is out of question.
Couple with changing from 1" to APS-C, that put a lot more restriction on the size. Therefore I do not expect the G1 X III will have a fast lens or long zoom. As for the starting point of the lens. I personally prefer start from 24mm (equivalent) and take what ever short lele I can get with a reasonable size.
okaro said:Rocky said:This is a G series camera. I think one of the requirement is "coat pocketable" and versatile. Therefore long Super zoom is out of question, fast medium zoom is out of question, may be even fast short zoom is out of question.
The G1 X is already hardly pocketable. Compare it to G15:
http://camerasize.com/compact/#534,383,ha,t
It is a pure example of a compact camera, not a pocket camera. Nobody is talking about a superzoom. That would be insane.
okaro said:Rocky said:Couple with changing from 1" to APS-C, that put a lot more restriction on the size. Therefore I do not expect the G1 X III will have a fast lens or long zoom. As for the starting point of the lens. I personally prefer start from 24mm (equivalent) and take what ever short lele I can get with a reasonable size.
First G1 X is not an one inch sensor. The sensor crop ratio is about 1.85 though the way it is used creates a crop ratio of 1.95. What you describe is basically what it already has.
traveller said:Nonsense. Of course you can fit a G1XII in a coat pocket, (not your jeans pocket -your down to Sony RX100 size for that requirement) how else are do you carry the camera about? Oh, don't tell me -you use one of those straps with "Canon Powershot" written on it? I bet you think that this looks cool!
Lots of people fit the Fuji X100 series or the EOS-M with the EF-M 22mm f/2 in their pocket, so why shouldn't the G1XII fit? http://camerasize.com/compact/#534,599.349,383,705,ha,t
There is no difference between a fixed lens camera with a 1" sensor with a 8.8-36.8mm f/1.8-2.8 zoom (e.g. the G5X) and one with an (Canon) APS-C sensor with a 15-62mm f/3.1-4.8 zoom or a full frame fixed lens camera with a 24-100mm f/4.9-7.6 zoom. They will all have exactly the same field-of-view range, capture exactly the same amount of light and have exactly the same depth of field control. They will also probably be exactly the same size. The only advantage would be if the 1" sensor and lens combo was cheaper than the APS-C or full-frame versions.
okaro said:traveller said:There is no difference between a fixed lens camera with a 1" sensor with a 8.8-36.8mm f/1.8-2.8 zoom (e.g. the G5X) and one with an (Canon) APS-C sensor with a 15-62mm f/3.1-4.8 zoom or a full frame fixed lens camera with a 24-100mm f/4.9-7.6 zoom. They will all have exactly the same field-of-view range, capture exactly the same amount of light and have exactly the same depth of field control. They will also probably be exactly the same size. The only advantage would be if the 1" sensor and lens combo was cheaper than the APS-C or full-frame versions.
True, but the G1 X is already f/2.0-3.9 with 1.95 crop. That s effectively 2/3 stops faster than the G5 X.
stevelee said:Explain to me how a lens at f/7.6 lets in the same amount of light as at f/2.8.
privatebydesign said:stevelee said:Explain to me how a lens at f/7.6 lets in the same amount of light as at f/2.8.
That's easy.
Take an 8mm f2.8 lens = aperture opening of 8/2.8 = 3.6 mm aperture opening.
Take a 27mm lens set to f7.6 = aperture opening of 27/7.6 = 3.6 mm aperture opening.
They are the same sized hole so they let the same amount of light in.
No, the aperture is at the focal point of the objective in a simple lens, the light path in a complicated one, so the angle of the light is not that relevant. Same hole size, same amount of light.okaro said:privatebydesign said:stevelee said:Explain to me how a lens at f/7.6 lets in the same amount of light as at f/2.8.
That's easy.
Take an 8mm f2.8 lens = aperture opening of 8/2.8 = 3.6 mm aperture opening.
Take a 27mm lens set to f7.6 = aperture opening of 27/7.6 = 3.6 mm aperture opening.
They are the same sized hole so they let the same amount of light in.
Assuming they gather that light from same angle.
stevelee said:I’m still confused. If it is the same amount of light, why does the camera consider it a different exposure?
Even with the same lens and lens opening you don’t always get the same amount of light, such as with extension tubes.
privatebydesign said:No, the aperture is at the focal point of the objective in a simple lens, the light path in a complicated one, so the angle of the light is not that relevant. Same hole size, same amount of light.okaro said:Assuming they gather that light from same angle.
stevelee said:I’m still confused. If it is the same amount of light, why does the camera consider it a different exposure?
Even with the same lens and lens opening you don’t always get the same amount of light, such as with extension tubes.
okaro said:privatebydesign said:No, the aperture is at the focal point of the objective in a simple lens, the light path in a complicated one, so the angle of the light is not that relevant. Same hole size, same amount of light.okaro said:Assuming they gather that light from same angle.
Totally incorrect. A wide angle lens gathers much more light from same size of aperture. Think about aperture of 10 mm. That could be a 20 mm wide angle at f/2 or a 160 mm Tele at f/16. The former gathers much more light.
okaro said:stevelee said:I’m still confused. If it is the same amount of light, why does the camera consider it a different exposure?
Even with the same lens and lens opening you don’t always get the same amount of light, such as with extension tubes.
Exposure is determined by light per square area of the sensor. If the light is spread to a larger sensor then one needs a higher ISO for the light to produce correct image. Of course the larger sensor can tolerate that so the overall image qualify is same.
stevelee said:Explain to me how a lens at f/7.6 lets in the same amount of light as at f/2.8.