View single post by Robert
 Posted: Wed Dec 9th, 2015 16:24
Robert



Joined: Mon Apr 2nd, 2012
Location: South Lakeland, UK
Posts: 4066
Status: 
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Yes, agreed! But if the satellite was at the position of the beginning of the streak at the start of the exposure and it travelled the distance of the length of the streak in 4 seconds, it could be a satellite... If it were a plane the streak would be stop-start, like dashes, as the navigation lights flashed.

In most photographs I have seen of meteors the intensity of the streak becomes greater as the meteor enters the atmosphere and then disappears very quickly, so the intense part is near the end of the streak. But some are like mine, fairly constant intensity, so some doubt exists, in my mind anyway.

Another factor which leans towards a meteor is the two adjacent images have no sign of the streak, the intervalometer was set at 20 seconds start to start of each exposure, so there would have been 16 seconds gap between exposures, very roughly I estimate just looking at the full image that there should have been a trace on at least the previous exposure and possibly the one before that too as the bright object approached.

The two meteor streaks I SAW, were quite long and the intensity grew as the meteors entered the Earths atmosphere, then they quickly expired.

Anyway, not a very exciting result from 4 hours of messing about in the dark and getting pretty cold but it was great fun doing it and the results aren't everything. It's given me a little more experience and hopefully when I do get a good night with plentiful meteors and a clear sky I will be able to make some nice pictures. It takes quite a bit of experimentation to get the settings right and I am not convinced they were perfect last night.

This was my first sorti with the D300s, I am hugely impressed and if the D3 is better, which I think it has to be, if only because of the FX sensor, I can't wait for that day.

I tried ISO 3,200 but it was a bit too noisy, so I backed off to ISO 1,600 which gave a cleaner image, while retaining reasonable speed. I ran the D200 alongside but by comparison it was a disaster. ISO 400 is the realistic maximum for a reasonably clean image, I was needing 30 second exposures at 45 second intervals (1 exposure every 45 seconds) to give it time to process and save each image. The battery life was terrible, I used four batteries to take 163 NEF's while the D300s took 585 NEF's and would probably have taken at least another 200 on just one battery, it is indicating more than half of the capacity remaining.

None of my batteries are prone to a particularly short capacity and I don't believe the one I used in the D300s was in any way different. All the batteries were fully charged before I left home. I assume the poor battery performance was as a result of the 30 second exposures and the processing for noise reduction in camera which was far slower than the D300s. I could have upped the number of exposures per minute from the D300s if I wished, probably to 6 per minute but I didn't want so many exposures, or perhaps I did? LOL

The only external difference between the two cameras was I had the Nikon ML-3 remote receiver plugged into the ten pin socket, but it was turned off, so it shouldn't have affected the battery life, should it? o.O



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Robert.