I was just about to say something about Howard’s exposures. I can’t see how 4
seconds at ISO 800 and f-2.8 did such a good job. I am usually at 20 -30
seconds, ISO about 1600 - 3200 at f-2.0 – 4.0 depending on the lens I have
mounted.
This shot is ISO 3200, f-3.8, 30 seconds and it was dark out of the box, even
with a substantial amount of moonlight.
http://gallery.leica-users.org/v/Aram/misc/m/Yosemite+Falls+Moonlight-13-Edit.jpg.html
Is there something magical about the Z7?
From: Frank Filippone
Sent: Monday, March 02, 2020 10:17 AM
To: leicareflex@xxxxxxxxxxxxx
Subject: [LRflex] Re: A starry night with the Z7 and Leica R28 and 100 APO
One of the predictors of star tracks, is this,,,,
Take the Focal Length of your lens. Divide that number into 250 ( more
conservative) or 500. The resulting number is the longest exposure time that
will leave minimal start tracks,,,,
Example..... using a 20mm lens, 500/20 = 25 seconds. More conservative?
250/20 = 12.5 seconds.
Alter the F stop or ISO to accommodate the shutter speed.
In general, the light itself for star photography @F2.8 and using an ISO of
3600 will be in the range of 10-20 seconds. (Do the math backwards and you
will see this example is for about a 24mm lens). Of course, you review at
your back LCD screen and see if you got what you wanted, then alter the ISO to
give you a "good" image quality.
YMMV
Frank Filippone
BMWRed735i@xxxxxxxxx
On Mon, Mar 2, 2020 at 7:35 AM Howard Cummer <hcummer@xxxxxxxxx> wrote:
Hi David,
I find I can go to 4 secs before the star trails show up - by 6 secs they are
quite noticeable.
Also I usually use a timer to open the shutter so that camera shake is
minimized. Didn’t do that with all the posted shots this time so
that could be improved upon.
Thanks for looking and suggesting. Always appreciated.
Howard.
From: David Young <dsy@xxxxxxxxxxxxx>
Date: Sun, 1 Mar 2020 19:25:45 -0800
Subject: [LRflex] Re: A starry night with the Z7 and Leica R 28 and 100 APO
A nice series, Howard. I quite like the moon shot. For the star shots with
the 100, you really need to up the ISO to get ride of the star trails caused by
the rotation of the earth.
Otherwise, it looks like you had a lot of fun!
David.
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