Re: [APML] milkyway panorama with EOS 10D

[Radu Corlan <rcorlan@pcnet.ro>]

On Tue, 24 Aug 2004, Stephan Messner wrote:

> Hi Bill,
> 
> >Wow!  Great job!  I'm also very impressed with the Sigma lens you
> >used. 
> >
> I was also suprised about the good quality of this lense.
> I tried also a sigma 12-24 lense but the quality was not so good.
> 
> > I don't have that lens but I do have the Sigma 28mm f/1.8 lens.
> >Have you got any idea of it's value in trying something like this?  I
> >also have the Canon 10D.
> >  
> >
> I don't hav ethe 28/1.8 but I think @ f/2.5 its possible to get good 
> results.

I have the Sigma 28/1.8 (with a Nikon mount) and i can say i'm not 
impressed. Even when used with a ccd chip (15x10mm) it shows "butterflies"
even at 2.8. On 35mm film, i wouldn't use it below f/4, and even there 
it's not that great (but i only did one test with film, so i may be 
wrong).

If you look at 

http://astro.corlan.net/events/perseid-1.jpg

it's the lower-left part of a frame taken with that lens at f/2 - you can 
see the astigmatism in the stars around the meteor. Those stars are about 
7mm from the center, and the image has been massaged a bit to hide the 
wings.

By comparison, a 50/1.2 Nikkor, which is marginal at 2.8 on 35mm film 
(shows "butterflies" in the extreme corners), is pretty much perfect in 
the central 15x10mm region even wide open.

Radu

> 
> >What sofwtare did you use for actually piecing together the panorama?
> >  
> >
> 
> I work with panormatools and PTGui
> http://www.ptgui.com/
> 
> this software ist very good for such projects.
> 
> >I would think it would be pretty hard to piece together frames from a
> >20mm lens!
> >  
> >
> 
> this was a very hard job! I needed over four weeks on the computer and 
> sometimes I was verry down.
> the disorientation with 20mm lenses is very hard and I must select 
> manuell over 1000 stars to register the images.
> PTGui stiched the panorama as a photoshop file with layers. so it was 
> possible to correct each single layer manually in PS.
> 
> 
> I tried also registar, but this fine program dont work for such large 
> panoramas.
> 
> Now I can't see any star more 8-)
> 
> grettings
> Stephan
> 
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> 

-- 

-------------
Radu Corlan       Snail Mail: Bucuresti sect. 1, 
rcorlan@pcnet.ro  str. Argentina nr. 28, Romania

   You can still escape the "Gates" of Hell!   
                 Use Linux!                       


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