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Posted: Tue Sep 30, 2008 9:58 pm
by iamlucky13
Thanks for the detailed post Mr. Pacholka! It looks like the kind of place that's worth going back to those 4 times, despite the long drive.

I hope the skepticism of those less personally familiar with night sky photography doesn't deter you from continuing to share your excellent images. Keep up the good work.

For those continuing to doubt, I offer an image from my personal collection for comparison. This was taken in dry weather, moderate humidity, in a modestly lit rural area (see the light on the trees). Exposure was 58 seconds, F/3.5, ISO 800, with a 28mm equivalent focal length and normal jpeg settings (limits how much you can bump up the brightness in photoshop). As you can see, star trails are barely visible. The brightest portion of the Milky Way is hidden by the trees and my higher latitude.

By my math, Wally's settings yield 70% more light than mine. I find his image quite believable, especially with additional processing of the RAW file.

Image

As an aside, I looked for more information on False Kiva. As you could guess by looking at the picture, it could be extremely vulnerable to vandalism. As a result, it's exact location is not publicly disclosed in Canyonlands park literature.

http://en.wikipedia.org/wiki/False_kiva

False Kiva name explained and Black Cloth (Shadow) explained

Posted: Tue Sep 30, 2008 10:03 pm
by Wally Pacholka
John,
In answer to your questions (below).
1. The False Kiva cave is so named because normally the Indian Kiva's were ceremonial places that had a room drilled out below the round rock circle, but in this case there is no room below and thus the name "False Kiva".
2. the Hale-Bopp photo with very noticable dard shadows behind the rocks is a "classic olden days" one frame single long exposure shot where the camera is tracked to follow the stars and the foreground, the rocks, in this case end up casting a shadow agaist the stars as the tracking device moves the camera in relation to the rocks and so the rocks get smeared or blurred against the stars. That's just how those older single image one exposure shots looked like. Of course there were the critics in those days that said they were two superimposed shots and that the person did just a lousey job at Photoshop to blend the two correctly because he left such a large shadow that anybody can see, when it fact they were real single image shots of that by gone era.
Anyone doing a seach on my images thru the years will see a progression from this older technique that showed shadows to now cristal clear star and foreground shots all in one exposure without such smears.
Check APOD Pacholka search or TWAN site or brightnightgallery.com
Wally



The one of which I wrote above was this:
http://antwrp.gsfc.nasa.gov/apod/ap040420.html
See what I meant about a back cloth?

But how about this one? Very recently on APOD.
No 'back cloth', a sharp horizon, yet no star trails.
The False Kiva pic is not the first in which he has acheived that.

John
PS Someone explain why "false" kiva, and what is a "kiva", please?

Posted: Tue Sep 30, 2008 10:12 pm
by JohnD
Wally,
Thank you for the detailed technical description, which is way beyond my capability, and for the location details. I did suspect that your technology might have changed between 04 and 08. but coild not guess how.

I'll look forward to more of your pictures!

John

Thanks, Wally...

Posted: Wed Oct 01, 2008 4:32 am
by walfy
I was one of the skeptics that felt superimposing of the sky was going on. I stand corrected! The lack of haze in the sky was the main culprit, and the moon light explanation clears it up. Very amazing effect.

I don't think anyone was trying to tear down Wally's work, just natural skepticism, and sincere curiosity as to how the image was put together.

That being said, the APOD page with the image says that it is a "single exposure image." Wally has informed us it is composed of 4 images, with the same exposure. Is it correct for APOD to say that this image is a "single exposure image" when it is made of 4 images with the same exposure? So the "single" applies to "exposure" only, and not to "image"? So maybe it is a perfectly accurate statement! Forgive me for letting you in on my feeble thought processes. Maybe it should be written as a "single-exposure image," with the dash clarifying things a little. Looks like the terminology has to catch up, or it already has and I'm way behind.

Most people were probably just trying to understand, so as to try and copy Wally's awesome techniques, of which I greatly appreciate that he share.

Posted: Wed Oct 01, 2008 2:51 pm
by bystander
Thanks, Wally, for your explanation. I've often admired your photographs. Two of my favorite APODs, APOD: 2007 August 7 - Old Faithful Below a Yellowstone Sky and APOD: 2006 August 1 - The Milky Way over Utah, have been yours, and now I think I can add a third. Another photo of yours that I really liked, though there are so many to choose from, is from your TWAN collection, Angel Trail. Keep up the great work. I look forward to seeing more of your work in the future.

APOD statement - single exposure

Posted: Wed Oct 01, 2008 7:06 pm
by Wally Pacholka
Hi this is wally again, the photographer that started this mess.
When I submitted the photograph to APOD I did not mention anything about exposure. When they run a photo they do not check with the photogrpher if everything in their comments are correct or not. Generally these guys are dead on accurate. These guys know me (as they have published me 28x prior) and in every case prior I have always submitted single image one frame sky/landscape shots so in this case they assumed this is Wally so it has to be single exposure. Keep in mind, I submitted a horizontal pano photograph so I could show the whole cave, but that pano is made up of 4 side by side sky/landscape shots where each frame is a shot of the sky and landmark(cave) all in one single exposure. This is no composite of the sky being put it. It is a horizontal pano stich of the sky and cave at once.
Hope I didn't add more confusion. With modern cameras with high iso and short exposures the sky and landmarks can be shot in one single exposure. Here I simply added 4 such shots together to give the viewer the complete view.
Wally

Posted: Wed Oct 01, 2008 7:32 pm
by orin stepanek
Wally; I hope you submit photos to APOD for a long time to come. I think your work is great. :)
Orin

Posted: Wed Oct 01, 2008 7:38 pm
by emc
Thank you Wally Pacholka, It is very cool that you are taking the time to address us in the forum. It adds depth and is exciting to have your personal feedback.

I like the mood this APOD sets... for me it strikes several aesthetic layers kind of like your multi-layered methodology for creating the image.