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the57man
01-08-2007, 07:13 PM
I have been in the dslr arena for about two years. I purchaced an e-300 evolt. As of present I have not been able to get a decent picture of a star filled night sky. With my film slr it was no problem. I want to take timelaps pictures but they seem to always wash out. Any ideas, Dave

kgosden
01-09-2007, 08:12 PM
Are you wanting just the sky or some of the landscape with the sky? I recently had some pretty good results with my E500 under a full moon. I do not have access to the photos on this PC, but I seem to recall ISO 400, wide open on my 11-22 zoom and ~10-15 second exposures. When I get home in a few days I will try to post one taken in front of the lodge in Zion NP in December '06.

Riley
01-09-2007, 11:19 PM
the difficulty is a combination of things

that stars are quite small in an image without considerable magnification
that exposures need to be relatively fast give a dark sky is best
that the earth rotates 15 degrees per hour, therefore long exposures have streaks rather than dots of light

the57man
01-09-2007, 11:50 PM
Say you wanted to take a picture of Orion which happens to be up right not How would you do it? I tried a 30sec exposure and got orion but also got a yellow sky. I would like to do a time exposure pointed directly at the north star for about 2 or 5 min to really acentuate the movement of the stars but I want a black sky. Dave

the57man
01-10-2007, 12:07 AM
I really love my E-300 dslr. I bought the kit with two lenses and then added a 35mm, 50-200 zoom, a close up extension, 1.2 teleconverter, and a fl-50 plus several filters and a battery pack that mounts to the camera. So you can see, I am in it for the long haul. I just want to take pictures of night skys with and without landscape and have a dark sky. Am I asking the camera to do to much??

Riley
01-10-2007, 12:22 AM
you will need to wait for a no moon night, or when the moon isnt at your part of the sky. Even its presence around the horizon lights up that part of the sky. The full moon is about 1/500th the light value of the sun

An exposure of some minutes will appear like streaks, known as star trails. An exposure exceeding 20 seconds will show some movement

I cannot explain the yellow sky but
perhaps you live in a city, and there are nearby sodium lights
they can reflect on the apparent atmosphere
the sky needs to be clear, thats why observatories are away from cities

i would mount the largest lens i could find, with 2x crop thats not hard to do, disable auto iso, and attempt exposures at around 15 seconds at various iso. and try to regain the exposure with post processing. maybe shoot RAW.

kgosden
01-10-2007, 11:11 PM
These are not the best samples particularly since I was really trying to capture the landscape under a full moon and not the sky. However, I thoguht these 100% crops might give you some idea as to what your E300 should be able to do. These are turned on their side to fit the size rules. Both were taken on a tripod around midnight in Zion NP near the lodge. There was some nearby electric lighting, but it was mostly behind me. The camera is an E500 with the 11-22 zoom.

The top photo is ISO100, 60 seconds, f2.8. The bottom is ISO 400, 15 seconds, f2.8. Both are at 11mm. A few of the 'stars' are hot pixels I believe. For my purposes they are not a problem.

Riley
01-11-2007, 12:21 AM
you can see in the top version that the stars are elongated due to rotation of the earth

since the sky has resolved so bright, you could probably use less exposure
but i guess it depends on what you are looking for

it really is the sort of thing where you have to play with exposures a bit

kgosden
01-11-2007, 09:25 PM
Riley, as I said I was not attempting to reproduce a dark sky. I just happened to have a few recent sample shots to show Dave what he might expect. Without the full moon I think I would have tried 10 seconds to get a dark sky. It might have cut down on a few hot pixels as well. Of course, it would probably be just as easy to nudge the curves a bit in PS after the fact.

the57man
01-12-2007, 03:56 PM
Thanks for the reply. I guess I need to stay under 20 sec. to get a crisp sky so you are right, I need to play with the exposure. Fortunatly , with digital I have an inexhaustable supply of film. Thanks again, Dave

Alina Borovikova
02-09-2007, 03:03 PM
old moon....

Alina Borovikova
02-09-2007, 03:05 PM
young moon...

Norm in Fujino
02-09-2007, 05:41 PM
Riley, as I said I was not attempting to reproduce a dark sky. I just happened to have a few recent sample shots to show Dave what he might expect. Without the full moon I think I would have tried 10 seconds to get a dark sky. It might have cut down on a few hot pixels as well. Of course, it would probably be just as easy to nudge the curves a bit in PS after the fact.

You should also turn on NR. Exposures over 4 seconds will be given a dark-frame subtraction exposure that will remove all the hot pixels.