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Share your Astrophotography Photos

lindam
Administrator
Administrator

Are you a fan of astrophotography? Post your favorite photo you've taken and share the story behind it. Be sure to include the Canon gear you used.

 

Astrophotography

91 REPLIES 91

Bob from Boston,

"You can see where the center of rotation is, and you know that a full rotation takes 24 hours."

 

Not really.  Several short exposures of, say 6 or 8, of approx. 5 to 10 minutes can do that.  It also eliminates a lot of error factors from long exposures. Another trick astro-photographers use is a 'fill flash' at the end to make foreground subjects show up more.  But in that shot I suspect the foreground trees would be washed out unless they were shot separately. Possibly in just one shot.  Don't you think?

EB
EOS 1DX and 1D Mk IV and less lenses then before!


@ebiggs1 wrote:

Bob from Boston,

"You can see where the center of rotation is, and you know that a full rotation takes 24 hours."

 

Not really.  Several short exposures of, say 6 or 8, of approx. 5 to 10 minutes can do that.  It also eliminates a lot of error factors from long exposures. Another trick astro-photographers use is a 'fill flash' at the end to make foreground subjects show up more.  But in that shot I suspect the foreground trees would be washed out unless they were shot separately. Possibly in just one shot.  Don't you think?


Yes, really. The Earth does a full rotation in 24 hours, regardless of how many exposures one takes to document the process. The answer to the question is the total exposure time; whether and how that time was broken into individual exposures is an implementation detail.

 

If the fill-flash method were what was used to illuminate the trees I'd expect them to show some color. As it is, they appear backlit (presumably by light from a city, given the pinkish color). I don't think it's necessary to posit a separate exposure for the trees, but it's certainly a possibility.

Bob
Philadelphia, Pennsylvania USA

Bob from Boston,

"Yes, really. The Earth does a full rotation in 24 hours, regardless of how many exposures one takes to document the process."

 

Yes, it may take the Earth nearly 24 hours to make a full rotation but it doesn't take 24 hours to make that shot.  I will guess you have not done it before?  I will also guess the exposure is not as long as you think.  It is, however, many shots.

When I suggested the idea of a fill flash, I didn't mean it for that shot.  Only that it is used a lot in this type of photography.  The lack of color in the trees suggests there was no extra light.

EB
EOS 1DX and 1D Mk IV and less lenses then before!


@ebiggs1 wrote:

Bob from Boston,

"Yes, really. The Earth does a full rotation in 24 hours, regardless of how many exposures one takes to document the process."

 

Yes, it may take the Earth nearly 24 hours to make a full rotation but it doesn't take 24 hours to make that shot.  I will guess you have not done it before?  I will also guess the exposure is not as long as you think.  It is, however, many shots.

When I suggested the idea of a fill flash, I didn't mean it for that shot.  Only that it is used a lot in this type of photography.  The lack of color in the trees suggests there was no extra light.


Where did I ever begin to suggest that it took 24 hours to make the shot? If that's what you thought I said, I obviously didn't make myself clear. And I see no evidence to support your assertion that the picture was made with multiple shots. The only conclusive evidence I can think of would be gaps in the individual trails, and I see none.

Bob
Philadelphia, Pennsylvania USA

"Where did I ever begin to suggest that it took 24 hours to make the shot? If that's what you thought I said, I obviously didn't make myself clear. And I see no evidence to support your assertion that the picture was made with multiple shots. The only conclusive evidence I can think of would be gaps in the individual trails, and I see none." 

 

I knew what you meant by your 24 hour comment.  I also thought it was a bit technical, also.  Hence, my comparison to an hour hand on a clock face.

 

Depending upon the focal length used to capture the shot(s), a pause in between shots of up to 10-15 seconds will not produce gaps in the star trails.  I also see the silhouette appearance of the trees as being highly suggestive that short exposures were involved.  I think that a really lengthy exposure should have lit up the trees a bit more than what they are. 

--------------------------------------------------------
"The right mouse button is your friend."

Bob from Boston,

"If that's what you thought I said, ...."

It is what I thought you said.  Smiley Frustrated   But whatever, any shot like that one is almost, no it is a certainty, several to many short shots.  It just isn't possible to do in one shot.

 

" I see no evidence to support your assertion that the picture was made with multiple shots."

That is because you don't do astro-photography.

EB
EOS 1DX and 1D Mk IV and less lenses then before!

" I see no evidence to support your assertion that the picture was made with multiple shots." 

 

That's the whole idea of it.  In film making, the best special effects are the ones that you don't notice: i.e. "Citizen Kane".

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"But whatever, any shot like that one is almost, no it is a certainty, several to many short shots.  It just isn't possible to do in one shot.

 

I gotta agree with Old Powershot on this one, Bob.  Sorry, Ernie.  All of the visual evidence I see not only points to mulitple shots, but quite possibly, and likely, dozens of them.

 

BTW, I think it would take 24 hours to "make" this shot because of all of the post processing I see involved, if I did it.Smiley Happy

--------------------------------------------------------
"The right mouse button is your friend."

" I see no evidence to support your assertion that the picture was made with multiple shots." 

 

That's the whole idea of it.  In film making, the best special effects are the ones that you don't notice: i.e. "Citizen Kane".

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"But whatever, any shot like that one is almost, no it is a certainty, several to many short shots.  It just isn't possible to do in one shot." 

 

I gotta agree with Old Powershot on this one, Bob.  Sorry, Ernie.  All of the visual evidence I see not only points to mulitple shots, but quite possibly, and likely, dozens of them.

 

BTW, I think it would take 24 hours to "make" this shot because of all of the post processing I see involved, if I did it."

 

 

???  Although my responce was to Bob from Boston, I think you got your tongue in front of your eye-teeth again and can't see waht you are saying. ???

EB
EOS 1DX and 1D Mk IV and less lenses then before!

"???  Although my responce was to Bob from Boston, I think you got your tongue in front of your eye-teeth again and can't see waht you are saying. ???" 

 

Nah, I was apologizing for saying "Old Powershot", meaning you.  Sorry, again.

--------------------------------------------------------
"The right mouse button is your friend."

Actually, "Old Powershot" fits pretty well. Smiley Very Happy   At least the "old" part that is.  Not much "Power" left.

No apologizing necessary.

EB
EOS 1DX and 1D Mk IV and less lenses then before!
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