[rollei_list] Re: OT: Digital Imaging and 'Stacking', Astro Imagery

  • From: Laurence Cuffe <cuffe@xxxxxxx>
  • To: rollei_list@xxxxxxxxxxxxx
  • Date: Thu, 29 Mar 2012 17:02:20 +0000 (GMT)



On Mar 28, 2012, at 04:35 AM, Marc James Small <marcsmall@xxxxxxxxxxx> wrote:

At 03:53 AM 3/28/2012, Laurence Cuffe wrote:


>It is, as I see it at this time, essentially a
>software problem. Using a High dynamic range
>methodology, taking two or three frames in quick
>succession, it should be possible to capture the
>dynamic range of conventional films. This method
>has been used to produce deeply weird results
>which are a current internet photography meme,
>but it could also be used to produce a more
>conventional image with more shadow detail and
>less blown highlights. This type of multiple
>frame image capture is already available in the
>mobile phone sector, and probably on some
>digital cameras, although I'm not aware of which ones.
>In practice shooting I would expect the entire
>capture process to take place on a fractions of
>a second time scale, which might preclude very
>active shots, but which would cover most normal
>shooting It would in principle be similar to
>the automatic bracketing that some high end film
>cameras indulge in if you let them.

Astronomers, professional and amateur, use this
'stacking' methodology. There are several folks
over on the Questar List at Yahoo! who routinely
do this. They prefer a dedicated
astrophotography camera, of course, and eschew
the finest of DSLR's. (These astrophotography
cameras are dedicated fixed-focus cameras with a
very high resolution over a small frame.) These
folks run this through a computer, normally a lap
top but, sometimes, their desk top models. They
normally shoot several THOUSAND images over a
relatively brief period and then 'stack' them for
publication. None of these folks are
professional photographers, though one is the guy
who shares with our former host, Brian Reid, the
reputation of having been the man who developed
the 'red state/blue state' dichotomy in US
politics. (I do not believe that either was
aware that the other was being credited with this
until I told them about it. They seem to be quite unacquainted.)

The cost of such a rig is relatively low. The
cost of the telescope may be high -- twenty years
back, I paid $1800 for my very used 1962 Quartz
3.5 Questar, more than I paid a year later for my
Rolleiflex 2.8GX -- and the lap top will cost
you $600 or so if you dedicate it to making
astrophotographs. The camera will cost you
anywhere from $200 and up to $2000, though even
the low-end models work quite well once you start
stacking. The software ranges in price from that
ultimate grin-maker, free, to around $1,000. A
minor charge for electricity, and Bob's your uncle.

I have reverted to my traditional role in hull
defillade and no longer take pictures, even with
the ease afforded by my Canon Rebel DSLR. When I
had a chemical darkroom, I loved to blast off ten
rolls and to process and print them, but, now,
with digital, the thrill is gone. I last shot
six or eight months back, and that was simply for
some happy-snaps of my wife meeting up wiith one
of her two nieces. (We are old folks: my wife
and I are now 62 and I believe Amber is in her
early 30's.) Forty years ago, an acquaintance in
the Nutmeg State told me that I was 'simply a
gear-head, no more and no less', and that fits me
in large measure. I am, in the end, much more
interested in HOW an image is produced than in
viewing the image. I am happy with my own
photographs but, at the same time, I really am
not a critical judge of photography in general.

A fellow on another photo list asked me if I was
going to rush out to photograph the conjunction
of three planets with our Moon. I laughed when I
got his query and simply said that I had done a
lot of astrophotography since 1963 but that I was pretty shut of it now.

Be well, Rollei People!

Marc

 
I appreciated you post, It inspires me to dig out my home made 8 inch Dob, or to do some more work on the 18 inch which up to now is just a collection of mirrors and parts for the mirror cell.  I have a Nikon D40, which I bought for its good low light performance, and I have got a couple of shots of the Andromeda Galaxy just putting the thing on a tripod, pointing it in the right direction, firing off the shutter, and just letting the camera decide when it was cooked.

I know the next step would be a Barn Door rig  etc, but my interest in astronomy is more of a put your eye up there and see what you can see one.

Your Questar is one of my dream machines, while bigger machines may see more and fainter, a telescope that size is a get up and go machine which is always ready.

One last thing which I find a joy in my astronomical explorations, is the free program stellarium http://www.stellarium.org/
This is one nicest digital planetarium program's I've found, and is a joy to use.

Re 62.  That, as many of the folks on this list will tell you, didoes even buy you into the game on being old We treasure you custodian ship of this list and your occasionally irascible and often opinionated contributions. There is a feeling here of sitting on some slightly southern back porch as the sun goes down with a scent of cigar smoke, or a good whiskey drifting past and a critical appreciation of life and all its technologies whether they be cameras, politics or ancient languages.

All the best

Laurence Cuffe.



msmall@xxxxxxxxxxxx
Cha robh bàs fir gun ghràs fir!

---
Rollei List

- Post to rollei_list@xxxxxxxxxxxxx

- Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe'
in the subject field OR by logging into www.freelists.org

- Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with
'unsubscribe' in the subject field OR by logging into www.freelists.org

- Online, searchable archives are available at
//www.freelists.org/archives/rollei_list

Other related posts: