It is currently Tue Jan 16, 2018 7:16 am




Post new topic Reply to topic  [ 154 posts ]  Go to page Previous  1, 2, 3, 4  Next
 ULTIMATE Astrophotography Resource Thread 
Author Message

Joined: Tue Feb 28, 2012 11:41 am
Posts: 5
Post Re: ULTIMATE Astrophotography Resource Thread
Hey, Jon,

Thanks for your reply!

As of now I'm more interested in taking wide angle shots of the sky, composing with parts of the landscape.
From (very small) experience I had from last week, stars would start trailing at 11mm (on a D7000) after 30 seconds -- this would be my longest exposure.

Would DSS still serve me for this case?

About your suggestions on taking the lights/blacks shots, so you meant that it doesn't need to be in a given order, just that I'd take, let's say 10 lights in a row, put the cap on and take 5 blacks in a row too?

This part I didn't understand well: "(...) and for better stacking, add bias and flat files too."
What are these bias and flat files?


Thank you very much for your kind help. :)


Best regards,
Rafael


Wed Feb 29, 2012 6:00 am
Profile

Joined: Fri Dec 30, 2011 3:25 pm
Posts: 19
Post Re: ULTIMATE Astrophotography Resource Thread
about 30 seconds sounds about right for 11mm wide angle. DSS will still help with that, I have not tried it myself,
and you might have to be careful if the ground or a tree is part of the picture. DSS will probably break the picture if it contains other then stars and sky..

yes, that is what I ment about the light/black. take several light first, then cap on and take dark.

Read the DSS-FAQ, it explains about the different type of files;
http://deepskystacker.free.fr/english/f ... flatoffset

_________________
--

Jon Ottar Runde
http://foto.rundeconsult.no
http://vimeo.com/jonorunde


Wed Feb 29, 2012 6:29 am
Profile
User avatar

Joined: Wed Mar 16, 2011 2:58 pm
Posts: 1348
Location: Denver, Colorado
Post Re: ULTIMATE Astrophotography Resource Thread
RAF2 wrote:
Hey, Jon,

As of now I'm more interested in taking wide angle shots of the sky, composing with parts of the landscape.

Best regards,
Rafael


since you are not tracking, just go ahead and shoot it the way you want, with the landscape and such. Then after you stack the images grab one of the light frames and edit out the sky, and paste that foreground in front of the star field.

Dishonest? maybe. The entire stacking process is sort of dishonest to begin with, every last pixel is already processed, and the image you get is not what you CAN see but what you can not. So go ahead and go the extra mile and slap a foreground on it.

Ive done this, but i try to be as faithful as i can, meaning i dont stick orion over something facing north, i take all my images at the same spot and only use those images.

here is an example, this was shot in february 2011 in sedona arizona, that is courthouse rock on the left, with bell rock on the right. The starfield i shot at an angle maybe 15 degrees higher than foreground, but at the same direction. South i believe. Then in post processing i stacked the starfield which of course screwed up the foreground, then i cut out the stars on the foreground image and superimposed the landscape in front of the stars.

like i said, it still feels a bit dishonest, but it is an impossible photograph with current sensor technology, so all we can do is at least try to be as faithful to the actual landscape as possible.

Image

_________________
http://www.BioLapse.com
http://www.TheChronosProject.com


Wed Feb 29, 2012 7:28 am
Profile

Joined: Tue Feb 28, 2012 11:41 am
Posts: 5
Post Re: ULTIMATE Astrophotography Resource Thread
Jack and Jon, thanks a lot for the orientation. I appreciate these a lot. :)

Jon, I'll put the cap for last then. I'll also read that FAQ about the types of files, thanks for the link.

Jack, I understand what you mean and I also try to get the most possible before doing any sort of editing. But like you said, when we come upon a barrier (current sensors' technology), IMO is acceptable to resort to some editing as long as it appears as less obtrusive as possible.

Nice image, it looks very natural indeed, the work was done softly and gently. Congratulations. :)


Best regards and thanks,
Rafael


Wed Feb 29, 2012 8:07 am
Profile
User avatar

Joined: Thu Dec 08, 2011 12:31 pm
Posts: 54
Location: Covina, CA (LA area)
Post Re: ULTIMATE Astrophotography Resource Thread
Jack Ripper wrote:
Dishonest? maybe. The entire stacking process is sort of dishonest to begin with, every last pixel is already processed, and the image you get is not what you CAN see but what you can not. So go ahead and go the extra mile and slap a foreground on it.


You bring up an interesting point. But since what we do here is really "art" and not science it doesn't seem like there is a "dishonest" way of creating our finished product. However, you may find the work interesting of an organization named TWAN (The World At Night). This group was started a few years ago and the contributors are invited to join them, needless to say I have not received my invitation yet. Anyways, it's collection of photos and timelapses from a community of photographers from all over the planet. Of note is that ALL of the photos are one off. No stacking, or combining of multiple shots. However, even with that restriction much of the work is incredibly beautiful. Not only are their shots composed with wonderful landscapes but many of the images are shot at World Heritage sites.

Following in an example of some of the work from TWAN, taken by Wally Packolka, accountant by day from Long Beach, CA. He has spoken at our astronomy club a few times and is really a great guy. Remember, this is a single shot. I'd be happy to get these results with 10 hours of data!

Image

And the link for the home page of TWAN

http://www.twanight.org/newTWAN/index.asp

Thanks Jack for all your work and interesting contributions.

_________________
Canon Rebel T3i, Canon Lenses: 8-15mm f4 Fisheye, 24mm f1.4, EFS 15-85, Losmandy Starlapse, DP Dolly
Astro: Takahashi FSQ 106, Vixen R200ss, G11&Titan mounts, QSI585
Riverside Astronomical Societyhttp://www.rivastro.org http://www.melnykastro.com


Sun Mar 04, 2012 11:28 pm
Profile

Joined: Tue Feb 28, 2012 11:41 am
Posts: 5
Post Re: ULTIMATE Astrophotography Resource Thread
Mark, thanks for the heads up on TWAN.

Their portfolio is amazing as well, very nice indeed.

This Wally Packolcka's image is beautiful - would they normally mind in sharing the EXIF so we can study these?


Best regards,


Mon Mar 05, 2012 5:20 am
Profile
User avatar

Joined: Thu Dec 08, 2011 12:31 pm
Posts: 54
Location: Covina, CA (LA area)
Post Re: ULTIMATE Astrophotography Resource Thread
RAF2 wrote:
This Wally Packolcka's image is beautiful - would they normally mind in sharing the EXIF so we can study these?


I have one of Wally's images "False Kiva" in my office that I occasionally refer to hoping to be able to replicate once I grow up. You can find out more about his work at his website http://astropics.com/

If think the basic technique here is first and foremost great composition and then as long as possible exposure at a high ISO and noise reduction, followed with careful work in in Photoshop to bring out the fainter areas without bringing up too much noise. Remember these are single shots without the benefit of stacking.

Also, Dennis Mammana, another TWAN member, is from the So Cal area and does seminars occasionally and also arranges trips to Alaska to go aurora hunting at least once a year. He is a regular presenter at Nightfall each year which takes place around late Oct/early November (depending on the New Moon schedule) in Borrego Springs, CA. Nightfall is long weekend get away for astro-imagers put on by the Riverside Astronomical Society, Ralph Megna and his minions.

_________________
Canon Rebel T3i, Canon Lenses: 8-15mm f4 Fisheye, 24mm f1.4, EFS 15-85, Losmandy Starlapse, DP Dolly
Astro: Takahashi FSQ 106, Vixen R200ss, G11&Titan mounts, QSI585
Riverside Astronomical Societyhttp://www.rivastro.org http://www.melnykastro.com


Mon Mar 05, 2012 8:50 am
Profile

Joined: Sun Oct 23, 2011 6:58 am
Posts: 15
Post Re: ULTIMATE Astrophotography Resource Thread
RAF - I'm interested in how you come with your stacking. I recently did a trip to Big Bend and took a bunch of wide angle star pics using D7000 and the Tokin 11-16, set at 11. First think I noticed is I got pill shaped stars at 30" so switched to 25". I think what I settled on was 11mm, 25", 28" interval, f 2.8 and iso 2500. The single frames came out quite well. However I have not been able to get a decent stacked photo. I took a couple of sets of 20-10 lights-darks and tried to stack them in Nebulosity and the program is, apparently, just unable to handle the non-tracked pics. It will line up well in some areas but not well at all in others. Here is a single frame:

Image

I can put up the stacked resule if anyone is interested. If anyone has used similar set up as above and gotten them to stack nicely in a program I'd like to hear. I'm on a mac is why I haven't tried DSS. I have a windows machine i could use though if people thought another program would stack correctly. Lets see if I can post an image, here is one of the MW shots I took from the South rim. Thanks, Cory

I posted this in a thread below but haven't gotten any responses.


Mon Mar 05, 2012 9:55 am
Profile
User avatar

Joined: Thu Dec 08, 2011 12:31 pm
Posts: 54
Location: Covina, CA (LA area)
Post Re: ULTIMATE Astrophotography Resource Thread
Costa1973 wrote:

...stack them in Nebulosity and the program is, apparently, just unable to handle the non-tracked pics.


Costa - have you tried the yahoo group associated with Nebulosity or Stark-Labs. They have a very active group.

Mark

_________________
Canon Rebel T3i, Canon Lenses: 8-15mm f4 Fisheye, 24mm f1.4, EFS 15-85, Losmandy Starlapse, DP Dolly
Astro: Takahashi FSQ 106, Vixen R200ss, G11&Titan mounts, QSI585
Riverside Astronomical Societyhttp://www.rivastro.org http://www.melnykastro.com


Mon Mar 05, 2012 12:11 pm
Profile

Joined: Sun Oct 23, 2011 6:58 am
Posts: 15
Post Re: ULTIMATE Astrophotography Resource Thread
I have not, thanks Mark, I will check it out!


Mon Mar 05, 2012 12:35 pm
Profile
User avatar

Joined: Thu Dec 08, 2011 12:31 pm
Posts: 54
Location: Covina, CA (LA area)
Post Re: ULTIMATE Astrophotography Resource Thread
RAF2 wrote:

This Wally Packolcka's image is beautiful - would they normally mind in sharing the EXIF so we can study these?



I sent your question out to Wally and the following are his details:

"Photo info on my Monument Valley meteor shots was something like 850 shots at 20 to 25 sec each F/2.2 @ ISO 1600 using canon 5d w 24mm f/1.4 lens or 35mm F1.4 lens over 3 nights one cloudy, capturing 5 solid meteor keepers. It was 17 degrees at night, slept in van.
99% of all TWAN images are single shots, and usually noted as composites if not, except the Pano's which are side by side stichings."

I hope this is helpful - Mark M

_________________
Canon Rebel T3i, Canon Lenses: 8-15mm f4 Fisheye, 24mm f1.4, EFS 15-85, Losmandy Starlapse, DP Dolly
Astro: Takahashi FSQ 106, Vixen R200ss, G11&Titan mounts, QSI585
Riverside Astronomical Societyhttp://www.rivastro.org http://www.melnykastro.com


Mon Mar 05, 2012 9:47 pm
Profile

Joined: Tue Feb 28, 2012 11:41 am
Posts: 5
Post Re: ULTIMATE Astrophotography Resource Thread
Hi, Mark,

Thank you very much for being so helpful and even going beyond and contacting the author himself to ask. That's very kind of you. His "False Kiva" is amazing, there are really great works on his website.

About the images, I have a preference for compositing with the landscape and working with RAW files to do some post-processing on Lightroom (instead of Photoshop) later. Sometimes I was afraid of a strong noise removal setting removing faint and small stars on ISO 6400 images, but haven't tried yet. Do you think this could happen?
I'm aware that a strong NR can remove some textures of landscape, like rocks and such, but not sure yet about it removing faint and small stars.


Costa1973, I haven't had the opportunity to go back to my spot for more night shots, as it is quite far and I'm able to go there mostly when there's a long weekend (with holidays). But as soon as I get the opportunity, I'll be there and will try some stackings after. :) But my preference is to have the image made out of a single shot with the most details as possible. I'm thinking on the next time to crank the ISO up to 6400 as the D7000 can handle this reasonably (I guess - haven't tried on astrophotography yet) together with f/2.8, 11mm and 25" exposure.


Best regards,


Tue Mar 06, 2012 6:09 am
Profile
User avatar

Joined: Wed Mar 16, 2011 2:58 pm
Posts: 1348
Location: Denver, Colorado
Post Re: ULTIMATE Astrophotography Resource Thread
markmelnyk wrote:

Photo info on my Monument Valley meteor shots was something like 850 shots at 20 to 25 sec each F/2.2 @ ISO 1600 using canon 5d w 24mm f/1.4 lens or 35mm F1.4 lens over 3 nights one cloudy, capturing 5 solid meteor keepers.

I hope this is helpful - Mark M


850 shots, five meteor keepers. UGH. Props for the efforts, but there is an easier way for that stuff.

I have found a way to nail what looks like a meteor everytime, by waiting for Iridium flares.

http://www.heavens-above.com/

register, add your location, and it will tell you exactly when an iridium flare will be visable at that location, and where it will be.

What is an iridium flare? it is the sun reflecting off the solar panels of Iridium Satellites they can be extremly bright, they are much slower than meteors, and a lot of fun to shoot. Im trying to be the first kid on my block to collect them all!

here is an iridium flare i captured last summer.
Image

These can be a LOT of fun to shoot. :)

This one is Iridium 29
Image

For a single shot starfield, I took my Canon 60D out last year before it got too cold, here is a single shot taken from the center of the milkyway, 50mm f/2, iso 6400 30 seconds tracked. Im already sold for canon being better for nikon for astrophotography, my nikon never picks up those reds, if i had not blown the focus after a few shots and was able to stack these you would see all kinds off stuff.
Image

_________________
http://www.BioLapse.com
http://www.TheChronosProject.com


Tue Mar 06, 2012 6:56 am
Profile
User avatar

Joined: Thu Dec 08, 2011 12:31 pm
Posts: 54
Location: Covina, CA (LA area)
Post Re: ULTIMATE Astrophotography Resource Thread
Jack Ripper wrote:
850 shots, five meteor keepers. UGH. Props for the efforts, but there is an easier way for that stuff.

I have found a way to nail what looks like a meteor everytime, by waiting for Iridium flares.


Cool idea about the Iridium flares - hadn't thought about trying that...hmmmmmmmmmm

Understand though with Wally, part of the joy to him is capturing a meteor and he has some remarkable results. He loves to spend long nights under the stars trying to capture that occasional surprise jewel. The following image he took out in the Mojave Reserve several years ago. Our club's dark sky sight has a meteor camera, Landers CA, and a gentlemen in Riverside Ca, visual observed the same meteor and the with 3 sightings they were able to actually calculate a rough estimate of the path the meteor - way beyond my cranial capacity.

Image

Rats - I can't get the image to load - anyways if you want to see a spectacular example of this go to Wally's website Astropics.com and look under the Mojave Preserve images.

Jack, your'e right about the Canon. Since Canon came out with the 20Da (a camera with greater red sensitivity) a few years back they really have dominated the astropography community. It seems the few Nikons you see are because the owner already had a sizable investment in lenses before they headed down the dark side of astronomy, i,e. astrophogrpahy. This isn't to say you can't take good astropics with a Nikon, it's just that Canon dominates the field.

_________________
Canon Rebel T3i, Canon Lenses: 8-15mm f4 Fisheye, 24mm f1.4, EFS 15-85, Losmandy Starlapse, DP Dolly
Astro: Takahashi FSQ 106, Vixen R200ss, G11&Titan mounts, QSI585
Riverside Astronomical Societyhttp://www.rivastro.org http://www.melnykastro.com


Tue Mar 06, 2012 8:26 am
Profile
User avatar

Joined: Mon Jan 02, 2012 5:42 pm
Posts: 30
Post Re: ULTIMATE Astrophotography Resource Thread
Awesome info in here... I've enjoyed taking star trails for years but never had much luck stacking/tracking. Problem I keep running in to is that I work on a Mac and can't seem to find a good star stacking program that will TRACK the stars. I currently use StarStax - which is free and awesome for stacking my images for star trails, but has no tracking ability. I don't have a tracking rig, so I'm stuck using a stationary camera and stacking/tracking. I've read that Nebulosity is a good choice but wonder if there are any other recommendations for Mac users.


Wed Mar 21, 2012 2:05 pm
Profile

Joined: Tue Mar 27, 2012 1:44 am
Posts: 3
Post Re: ULTIMATE Astrophotography Resource Thread
Jack

I think the info that you have in this thread is amazing. i do have a couple of questions that Im hoping that you and the community as a whole will be able to shed some light on (no pun intended) for me

You talk a lot about stacking. This seems to me to be a process that is ideal for stills photography but unsuited for motion lapse photography. The quality of the photographs that you have used stacking on looks amazing and is definitley the degree of excellence that Im shooting for (sorry, no pun intended here either :D ) BUT looking at Toms motion lapse films he has constellations and the Milky Way drifting right the way across his skys.

My main questions is how on earth (or not as the case may be) is he ab le to get that level of detail out of the exposures that he is taking because to me it looks like he has more detail on each frame of his motion lapse...so how the hell can he do that? any ideas?

Secondly I am currently at RAF Akrotiri on the island of Cyprus visiting family and I have tried my first motiion lapses and whilst I am happy with the results I am still a loooooooong way from what I want so I wanted to ask how important light pollution is to the final result of a picture. Even though I am at a relatively secluded spot there will still be light pollution here from the military floodlights of the base

Anyway thanks in advance for all the help and I look forwards to hearing what your thoughts are

Lee 8-)


Tue Mar 27, 2012 2:02 am
Profile
User avatar

Joined: Wed Mar 16, 2011 2:58 pm
Posts: 1348
Location: Denver, Colorado
Post Re: ULTIMATE Astrophotography Resource Thread
Light pollution is your enemy, and it is increasingly hard to find a dark site to shoot from.

As for Toms timelapses, while he has an awesome level of detail, i would disagree that any single frame of his videos has more detail, first off what you are watching is at best 1080p. I think that is what, around 3mp image? and it speeding through a few dozen frames per second which also helps mask any noise. I would imagine he spends quite a bit of time pulling as much detail out of every frame he has, but i would put a good 12+mp stacked image against any frame of his video.

Getting the milkyway is not difficult and does not really require stacking. Im sure tom has a nicer equipment than i do, with a camera with a big full frame sensor with lenses that are every bit as good. Even sitting at f/4 at 12mm on a crop sensor camera you can get tons of wonderful milkyway detail. A full frame camera at 14-18mm would probably yield even better results.

Tom clearly has an awesome technique, I would be hesitant to put my best images against one of his images that he considers mediocre. then again, im pretty sure on the front of this site it lists him as the "Astronomy Photographer of the Year", Im not sure where that accreditation comes from, but from what i have seen at least on his night time timelapses I think it is probably well deserved.

_________________
http://www.BioLapse.com
http://www.TheChronosProject.com


Tue Mar 27, 2012 6:06 am
Profile

Joined: Fri Apr 06, 2012 7:29 pm
Posts: 10
Post Re: ULTIMATE Astrophotography Resource Thread
I signed up for this forum just for this thread. Freakin awesome. Anyways I have done a few star shots in the past and wanted to add my 2 cents in case this has not been covered. First of all I always remove any uv or solar filters from my camera because on multiple accounts I have had a reflection occur between my lens and the filter which creates an out of focus appearance particularly when trying to photograph the moon. Another thing that I don't hear about alot, is using a piece of fabric to cover your viewfinder during a shot because light leaks through it onto your sensor. My last tip comes from an old man I met while camping a few years back who had been doing night sky shots for a long time. He recommended using an aperture between 5.6 and 8.0 to ensure things remain in focus. This is quite contrary to a wide open aperture but he insisted. He and his friends had quite a few telescopes and cameras setup at the top of a mountain in ellijay north Georgia. They were using barn door trackers, and some were using dslr's mounted on light weight telescopes with their own electric tracking systems. It seemed pretty serious however I have not had any success getting proper exposures with an aperture higher than 4.5 on my T3i. Any ways I am going to try out the light/dark technique in a minute and I am excited so Ill post back later with results. Thanks to all who have contributed their knowledge to this thread


Fri Apr 06, 2012 7:47 pm
Profile

Joined: Fri Apr 06, 2012 7:29 pm
Posts: 10
Post Re: ULTIMATE Astrophotography Resource Thread
question. Has anyone tried high iso's on the canon 6400, 12800 and with magic lantern i think 25,600? I have used these in the past to find celestial objects without a long exposure, but could the light/dark software eliminate this heavy amount of noise?


Fri Apr 06, 2012 8:31 pm
Profile

Joined: Fri Jan 08, 2010 9:51 pm
Posts: 10
Post Re: ULTIMATE Astrophotography Resource Thread
Stumbled over here... Coincidentally I've been teaching a WEBINAR on Astrophotography. As JTR noted it is a very steep learning curve. You can see what folks have said about my previous courses (1, 2, 3).

I , like Tom carry a title I am proud of. I won "Astronomy Photographer of the Year" in 2010 - the same year as Tom. My category was "People and Space" whereas Tom was the overall winner. Coincidentally a very talented guy just miles from my home won in the same year for the category "Deep Space". So of the 5 prizes available, Californians took the lion's share.

I say this by way of background. I felt a bit guilty for taking such a title and having had little to no experience with Astrophotography and the stacking techniques that JTR has been speaking of... so I embarked on a journey and it wasn't long before I:

1. Learned that knowing astrophotography techniques can assist in LOTS of photography.
2. Was being asked repeatedly how I "pulled that off".
3. Managed to get shots like this from my BACK YARD in San Jose, CA. Dark skies help a lot, but you can get started without them:

Image
Colorful Neighbor

PS. Here is the tree I have dubbed "Tom's Tree". If you've seen the trailers or the movie, or the shot that won Tom the overall title for 2010 you'll understand why!

Image
Famous II [C_035478]


Wed May 30, 2012 1:26 pm
Profile

Joined: Fri Jan 08, 2010 9:51 pm
Posts: 10
Post Re: ULTIMATE Astrophotography Resource Thread
calypsob wrote:
question. Has anyone tried high iso's on the canon 6400, 12800 and with magic lantern i think 25,600? I have used these in the past to find celestial objects without a long exposure, but could the light/dark software eliminate this heavy amount of noise?


If what you're trying to achieve is a lovely image then the super high ISOs will get you to a point of diminishing returns. One shot at 6400 will be approximately twice as noisy as one at 3200 and so on. There is also such a thing as "Native ISO at Unity Gain". Once you exceed that you're not doing anything except amplifying the noise. That value is about 1800 for the 5D Mark II, and about 1000 or so for the 7D, and 350D.


Wed May 30, 2012 1:32 pm
Profile
User avatar

Joined: Wed Mar 16, 2011 2:58 pm
Posts: 1348
Location: Denver, Colorado
Post Re: ULTIMATE Astrophotography Resource Thread
StevenTheAmusing wrote:
Stumbled over here... Coincidentally I've been teaching a WEBINAR on Astrophotography. As JTR noted it is a very steep learning curve. You can see what folks have said about my previous courses (1, 2, 3).

I , like Tom carry a title I am proud of. I won "Astronomy Photographer of the Year" in 2010 - the same year as Tom. My category was "People and Space" whereas Tom was the overall winner. Coincidentally a very talented guy just miles from my home won in the same year for the category "Deep Space". So of the 5 prizes available, Californians took the lion's share.

--snip--




WOW! Let me humbly step aside, I've learned enough to not completely embarrass myself, but I would probably never get such an award myself.

I started learning about AP and yeah, the learning curve was crazy, i also couldnt find any good resources, just small bits of information here and there that i pieced together to start figuring it out. I have several of these threads on various forum boards to just help people start getting the basics of it. Hopefully i have not screwed everything up. ;)

Anyway, thank you for posting on here, I really appreciate that you took the time to stop by. If there is anything on here I have wrong let me know, I have no ego on this stuff and i would rather be corrected than to pass off bad information.

_________________
http://www.BioLapse.com
http://www.TheChronosProject.com


Wed May 30, 2012 1:55 pm
Profile
User avatar

Joined: Wed Mar 16, 2011 2:58 pm
Posts: 1348
Location: Denver, Colorado
Post Re: ULTIMATE Astrophotography Resource Thread
StevenTheAmusing wrote:
calypsob wrote:
question. Has anyone tried high iso's on the canon 6400, 12800 and with magic lantern i think 25,600? I have used these in the past to find celestial objects without a long exposure, but could the light/dark software eliminate this heavy amount of noise?


If what you're trying to achieve is a lovely image then the super high ISOs will get you to a point of diminishing returns. One shot at 6400 will be approximately twice as noisy as one at 3200 and so on. There is also such a thing as "Native ISO at Unity Gain". Once you exceed that you're not doing anything except amplifying the noise. That value is about 1800 for the 5D Mark II, and about 1000 or so for the 7D, and 350D.



This is where stacking comes into play, if I'm wrong on this let me know, i dont think i woudl try anything over 6400 on modern sensors, but the idea is to take multiple images and average the values of each pixel in a given area, the algorythm will find a median value and keep it, this way the value over multiple images is examined and the noise is significantly reduced and extra detail is achieved.

ive done many with ISO 3200, on my Nikon D90 and D7000 with great results. I have not really managed to get my 60D out for AP work yet though.

_________________
http://www.BioLapse.com
http://www.TheChronosProject.com


Wed May 30, 2012 2:01 pm
Profile
User avatar

Joined: Mon Apr 09, 2012 10:46 am
Posts: 23
Location: Croatia
Post Re: ULTIMATE Astrophotography Resource Thread
I dont get the Light, Dark, Flat, Bias frames....dont know what to do to make them :twisted:

_________________
DBart


Thu Jun 21, 2012 3:30 am
Profile
User avatar

Joined: Wed Mar 16, 2011 2:58 pm
Posts: 1348
Location: Denver, Colorado
Post Re: ULTIMATE Astrophotography Resource Thread
domagoj_CRO wrote:
I dont get the Light, Dark, Flat, Bias frames....dont know what to do to make them :twisted:



Unless you are shooting through a telescope which will give nasty vignetting, the flats and bias's are not needed.

I have explained Lights and Darks in detail in the beginning of the thread, which part are you unclear about?

_________________
http://www.BioLapse.com
http://www.TheChronosProject.com


Thu Jun 21, 2012 6:00 am
Profile
User avatar

Joined: Mon Apr 09, 2012 10:46 am
Posts: 23
Location: Croatia
Post Re: ULTIMATE Astrophotography Resource Thread
Jack Ripper wrote:
domagoj_CRO wrote:
I dont get the Light, Dark, Flat, Bias frames....dont know what to do to make them :twisted:



Unless you are shooting through a telescope which will give nasty vignetting, the flats and bias's are not needed.

I have explained Lights and Darks in detail in the beginning of the thread, which part are you unclear about?


not with telescope,I`m doing it with Canon 600D,Canon 70 - 200mm F2.8 L, Samyang 8mm F3.5,stedy tripod,timer,Nd square filters (2,4,6,8).The DSS program I understand but I dont know what dark and light frames mean,I have read the tutorial in the beginning of the thread but I dont undestand it.You shoot without lens cap 10,20,or more light photos,example iso 800 ( I have noise after 800 ) F2.8 30" and shot about 10 20 photos,then I put lens cap,dont change a thing and shoot about 10 photos? I dont understand it because when you put cap on your lens you dont see a thing,well because you have a cap on your lens :shock: Sorry for not understanding anything,I just yesterday discoverd astrophotography and really want to learn this. :oops:

_________________
DBart


Thu Jun 21, 2012 7:03 am
Profile
User avatar

Joined: Wed Mar 16, 2011 2:58 pm
Posts: 1348
Location: Denver, Colorado
Post Re: ULTIMATE Astrophotography Resource Thread
sure.

That is correct, to gather your darks you leave the camera settings the same then take images of the back of the lens cap.

The lights are used to collect data for the image you want, however, when shooting high ISO they will be plagued by noise.

So by stacking the lights, the program will average out the values of each pixel which gives helps reduce noise.

To futher reduce the noise that is where the darks come in. By shooting the back of the lens cap any variances in the pixels us understood by the stacking program to be anomalies, ideally it should be 100% black pixels the same value from corner to corner, however this is not the case. So by looking at the values of each pixel on the darks it builds a sort of profile for the sensor and how it is performing at that moment in time, it then uses this data to further subtract noise introduced by the sensor due to heat, hot pixels, etc.

If you check your camera settings for "Long Exposure Noise Reduction" you will notice if you do a 10 second exposure, that afterwards the camera processes for another 10 seconds or so. This is the camera doing a simple single image stack with one light frame, and one dark frame which it takes after the shutter closes.

it is basically the same process, however by stacking multiple lights and applying a stack of darks to the stack of lights you get dramatically more impressive results.

Does that help?

_________________
http://www.BioLapse.com
http://www.TheChronosProject.com


Thu Jun 21, 2012 8:02 am
Profile
User avatar

Joined: Mon Apr 09, 2012 10:46 am
Posts: 23
Location: Croatia
Post Re: ULTIMATE Astrophotography Resource Thread
Jack Ripper wrote:
sure.

That is correct, to gather your darks you leave the camera settings the same then take images of the back of the lens cap.

The lights are used to collect data for the image you want, however, when shooting high ISO they will be plagued by noise.

So by stacking the lights, the program will average out the values of each pixel which gives helps reduce noise.

To futher reduce the noise that is where the darks come in. By shooting the back of the lens cap any variances in the pixels us understood by the stacking program to be anomalies, ideally it should be 100% black pixels the same value from corner to corner, however this is not the case. So by looking at the values of each pixel on the darks it builds a sort of profile for the sensor and how it is performing at that moment in time, it then uses this data to further subtract noise introduced by the sensor due to heat, hot pixels, etc.

If you check your camera settings for "Long Exposure Noise Reduction" you will notice if you do a 10 second exposure, that afterwards the camera processes for another 10 seconds or so. This is the camera doing a simple single image stack with one light frame, and one dark frame which it takes after the shutter closes.

it is basically the same process, however by stacking multiple lights and applying a stack of darks to the stack of lights you get dramatically more impressive results.

Does that help?


yes,thanks really for all your help,much appreciated!....one more quetions...is there a rule for how much black photos you need to take? lets say I shoot 15 or 10 light photos,how mutch black photos I need to shoot?

_________________
DBart


Thu Jun 21, 2012 9:02 am
Profile
User avatar

Joined: Wed Mar 16, 2011 2:58 pm
Posts: 1348
Location: Denver, Colorado
Post Re: ULTIMATE Astrophotography Resource Thread
as many as time permits, i shoot with a 2:1 ratio of lights to darks. So if i manage to get 20 lights, ill try to get at least 10 darks.

Some more accomplished astrophotographers will actually do a HDR type deal where they might for example take 100 lights at 1 minute each, then 50-100 darks, go out the next night and take 100 lights at 45 seconds then 50-100 darks, and go out the third evening then take 100 lights at 30 seconds and 50-100 darks.

in this case they are also usually using guided telescope mounts and shooting through telescopes.

ive read threads in other forum boards for astronomers where they actually keep repeating this pattern for 2-3 months shooting the same object in the sky gathering image data, then wait for that object to get back in the right position and start at it again the following year.

lol

So, when i say i do 30 lights and 15 darks, i am actually really not even beginning to scratch the number of shots you can get. 30 lights and 15 darks if done properly will definatly get a few "oohs" and "ahhhs" from your friends, but pales in comparison to the folks that run images over the course of years. :)

but if you are NOT doing deep space objects like galaxies and nebulas and shooting for wide starfield, usually under 50 lights and 25 darks will yield superb results. If you have foreground content you really limit how many shots you can take before the stars have shifted. so a lot of the time the foreground is wiped out from the stack and re-added from a single frame later in post processing.

_________________
http://www.BioLapse.com
http://www.TheChronosProject.com


Thu Jun 21, 2012 9:15 am
Profile
User avatar

Joined: Mon Apr 09, 2012 10:46 am
Posts: 23
Location: Croatia
Post Re: ULTIMATE Astrophotography Resource Thread
thank you very mutch,...as soon as my 8mm fisheye arrives I will try something like this:
http://farm2.static.flickr.com/1218/515 ... cf35_o.jpg

_________________
DBart


Thu Jun 21, 2012 9:37 am
Profile

Joined: Sat Dec 24, 2011 10:51 am
Posts: 3
Post Re: ULTIMATE Astrophotography Resource Thread
Can I do a stack photo without the tracker?


Tue Jul 24, 2012 5:56 pm
Profile
User avatar

Joined: Mon May 14, 2012 3:49 am
Posts: 54
Post Re: ULTIMATE Astrophotography Resource Thread
KostiaW88 wrote:
Can I do a stack photo without the tracker?


yes, the stacking software will take the stars in the images and align them. what im not sure about tho, as ive not yet done it, is what happens to the stars at the edges that either move into or out of the frame during shooting, ie whether these appear as dimmer, 'non stacked' stars at the edge or are simply cropped? perhaps someone can answer me that

were having some nice weather in the uk at the minute i should really get my arse into gear whilst the moons still relatively new and find out myself

_________________
I reserve the right to take back any of the noob things I post on this forum!


Wed Jul 25, 2012 12:13 am
Profile

Joined: Sat Dec 24, 2011 10:51 am
Posts: 3
Post Re: ULTIMATE Astrophotography Resource Thread
ezroller wrote:
KostiaW88 wrote:
Can I do a stack photo without the tracker?


yes, the stacking software will take the stars in the images and align them. what im not sure about tho, as ive not yet done it, is what happens to the stars at the edges that either move into or out of the frame during shooting, ie whether these appear as dimmer, 'non stacked' stars at the edge or are simply cropped? perhaps someone can answer me that

were having some nice weather in the uk at the minute i should really get my arse into gear whilst the moons still relatively new and find out myself


Thank you, I want to try take a photo stack of stars with view of tree or something like this,but I don't know if its possible without the traker. I am really can't imagine how it possible if the stars moving and the tree don't moving.


Wed Jul 25, 2012 5:50 am
Profile
User avatar

Joined: Mon May 14, 2012 3:49 am
Posts: 54
Post Re: ULTIMATE Astrophotography Resource Thread
KostiaW88 wrote:
ezroller wrote:
KostiaW88 wrote:
Can I do a stack photo without the tracker?


yes, the stacking software will take the stars in the images and align them. what im not sure about tho, as ive not yet done it, is what happens to the stars at the edges that either move into or out of the frame during shooting, ie whether these appear as dimmer, 'non stacked' stars at the edge or are simply cropped? perhaps someone can answer me that

were having some nice weather in the uk at the minute i should really get my arse into gear whilst the moons still relatively new and find out myself


Thank you, I want to try take a photo stack of stars with view of tree or something like this,but I don't know if its possible without the traker. I am really can't imagine how it possible if the stars moving and the tree don't moving.


as mentioned earlier i think the best route is to edit in a single shot of the foreground over the stacked images, i can imagine a good way to do this is to shoot the star images for stacking just of the sky without any foreground to avoid the blurred effect you see on some images. it is cheating a little but i cant think of a way to get stacked images and a sharp foreground, unless you can stop the earths rotation!

bear in mind that although a tracker would help you get better shots to stack with, and you wouldnt 'lose' the edges of the image as the shots youd be stacking would all look the same, you will still encounter a blurred foreground as instead of the earth rotating it will be the tracker that moves

_________________
I reserve the right to take back any of the noob things I post on this forum!


Wed Jul 25, 2012 6:07 am
Profile

Joined: Sat Dec 24, 2011 10:51 am
Posts: 3
Post Re: ULTIMATE Astrophotography Resource Thread
In my opinion, the best way to do one photo with foreground and good view of stars its only take a shoot of foreground and take the shoot of stars in stack technique and combine them to one shoot. Or we have other way to do this?
I am don't wont to buy a tracker because I only learn this and its not my main kind of photography. Sorry about the low level of English :-)


Wed Jul 25, 2012 1:25 pm
Profile

Joined: Mon Feb 01, 2010 2:33 pm
Posts: 281
Location: Victoria, Canada
Post Re: ULTIMATE Astrophotography Resource Thread
Low level of english is not a concern here. Most of us are geeks and nerds and know how to 'translate' what other nerds say into meaningful dialogue. And if you can't express yourself in words, pictures work just fine.


Wed Jul 25, 2012 3:05 pm
Profile

Joined: Thu Feb 24, 2011 5:37 pm
Posts: 331
Location: Córdoba, Argentina
Post Re: ULTIMATE Astrophotography Resource Thread
A quick question to Canon shooters. I've noticed since I started shooting at night that when there's moonlight, I usually have to overexpose 1 stop more than what the camera light meter says. This happen to me on a 450D and a 60D. Anyone else is experiencing this? Is this a Canon only thing?

_________________
www.leandroperez.com.ar


Wed Jul 25, 2012 7:59 pm
Profile
User avatar

Joined: Mon Nov 16, 2009 4:36 pm
Posts: 387
Location: Australia
Post Re: ULTIMATE Astrophotography Resource Thread
leandroprz wrote:
A quick question to Canon shooters. I've noticed since I started shooting at night that when there's moonlight, I usually have to overexpose 1 stop more than what the camera light meter says. This happen to me on a 450D and a 60D. Anyone else is experiencing this? Is this a Canon only thing?

I tend to use a rule of thumb calc for moonlit exposures which depends on the day of the lunar month, rather than use the light meter. Others probably do the same. It goes like this: For the 1st 4 or 5 days around new moon, just use the exposure you would on a dark moonless night. From then on, reduce by 1/3 of a stop for each night up to full moon. That get's you close. Full moon is around 3 stops brighter than no moon.

_________________
vimeo


Thu Jul 26, 2012 5:25 am
Profile

Joined: Thu Feb 24, 2011 5:37 pm
Posts: 331
Location: Córdoba, Argentina
Post Re: ULTIMATE Astrophotography Resource Thread
colinmlegg wrote:
leandroprz wrote:
A quick question to Canon shooters. I've noticed since I started shooting at night that when there's moonlight, I usually have to overexpose 1 stop more than what the camera light meter says. This happen to me on a 450D and a 60D. Anyone else is experiencing this? Is this a Canon only thing?

I tend to use a rule of thumb calc for moonlit exposures which depends on the day of the lunar month, rather than use the light meter. Others probably do the same. It goes like this: For the 1st 4 or 5 days around new moon, just use the exposure you would on a dark moonless night. From then on, reduce by 1/3 of a stop for each night up to full moon. That get's you close. Full moon is around 3 stops brighter than no moon.

Thanks for the tip, Colin. I'll try it next time I shoot.

_________________
www.leandroperez.com.ar


Thu Jul 26, 2012 7:33 pm
Profile
User avatar

Joined: Wed Aug 01, 2012 11:10 am
Posts: 4
Post Re: ULTIMATE Astrophotography Resource Thread
Hello Jack , you are my mentor at the moment , i have read and re read and studied all posts, but i aint getting the same results as your photos , i do stack with dss , i also try to boost a single frame in photoshop ,, i also read that you used a tonika f4 to get fantastic results ,,, i have a canon 40d with a sigma 10-20 f4 or a 25-105 f4 ,, , i think my images have enough stars ,but not enough detail, i guess my question is do you have a guide on what settings you use in dss, and how good should it look before and after dss ,and how much finishing off happens in ps ,,, many thanks for your time nick ,

i will try to upload a pic in a bit !!!!


Wed Aug 01, 2012 11:24 am
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 154 posts ]  Go to page Previous  1, 2, 3, 4  Next


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © phpBB Group.
Designed by Vjacheslav Trushkin for Free Forums/DivisionCore. pozycjonowanie