|Exposure: Aperture F8| Shutter Speed 60s| ISO 200|
|Exposure: Aperture F8| Shutter Speed 15min| ISO 800|
I borrowed Panasonic Lumix GX1 from my friend Alex to do a night photography field test, to see if it can be used for night photography. Night photography requires long exposures, this feature is a must, and surprisingly GX1 does support up to 60 seconds exposure and bulb mode. On the plus side, it also has long exposure noise reduction(LENR), this feature is useful if we are not going to do image stacking for star trail, otherwise it should be turned off.
To do a field test, I used Steve Harper's Moony 8 Rule - Aperture F8, Shutter Speed 4-8 Minutes, ISO100. Since base ISO of GX1 is 160 and maximum 60 seconds shutter speed without cable release, I chose to test with the setting of Aperture F8, Shutter Speed 60 Seconds, ISO400 and the result had sadden me, I dialed to ISO 200 to lose one stop of light and see how things go.
Here's the original copy of first image, you can click the image to zoom in -
And its 1:1 aspect ratio -
Notice the hot pixel noise? And this is at ISO 200 with 60 seconds exposure. The noise pattern is always the same. I have confirmed this by taking the dark frame with the lens cap on. As this is not luma/color noise, you can only fix it using dark frame subtraction.
So the question here is, can we use GX1 for night photography, the answer is tough one, if you are into learning night photography and this is the only camera you have, then go ahead and experiment with it, however if you are serious about night photography, and plan to make large print of your image instead of just looking good on the web, then the answer is no.
Updates: Regarding the hot pixel noise issue(fix speckle pattern), it maybe sensor defect on my friend's GX1 camera, Not many people will notice this defect unless they shoot long exposure(more than 1 second shutter speed and the speckle will start to appear). I'm yet to fully confirm about this until my friend sends to Panasonic for checking.