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Tips for taking pictures of the Milky Way tonight

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#1 Astro Pike

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Posted 17 July 2017 - 02:38 PM

I'm on holiday in rural France.

Fairly clear skies and little light pollution!

Last night I took some pictures from the garden. 

Here's an example:

 

20017770_1867555666899037_29635453033444

 

They were taken with a Canon 450D and a Samyang F/20 16mm.

Exposure 30 seconds. ISO 1600.

There were some low floating clouds and the moon was rising.

I shot in raw and jpeg (the picture above is jpeg). I didn't edit it any further.

 

The stars are a trailing a bit. I guess tonight I should try an exposure of 20 seconds.

I'm afraid the milky way will be less visible.

 

I read something about stacking and flats, bias, darks etc.

Are flats, darks and bias necessary for stacking?

How many pictures should I take from the same part of the skies?

How many darks, flats and bias should I take?

 

All suggestions are welcome to enhance the quality of the pictures!


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#2 MCovington

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Posted 17 July 2017 - 02:48 PM

This might not be the time to master a new technique, but at minimum, set your camera to record raw images as well as JPEGs.

 

Then take as many as 20 to 50 5-second exposures, all alike, for stacking.

 

To avoid the need for darks, you can turn on long exposure noise reduction in your camera. That will make it automatically expose and subtract a dark after every exposure.

 

You can do without flats and flat darks, although they will counteract the vignetting of your lens.  To take flats, use the same ISO setting, lens, and f-number as for the Milky Way, and put a white handkerchief over the lens and take maybe 10 flats (blank fields) exposed to be slightly lighter than mid-gray.   All should have the same exposure time (which will obviously be a LOT shorter than 5 seconds).

Then take flat darks, which are the same as the flats (same exposure) but with the lens cap on.

 

You can then do the processing with DeepSkyStacker as described here:
http://www.covington...#DeepSkyStacker

 

The main thing is to acquire at least 10 of each type of frames while you are at your dark site.  Subtle processing can be done later.


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#3 overnight

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Posted 17 July 2017 - 02:57 PM

Darks, Bias, and Flats are a must unless you do LENR as said above, then you don't need darks. I prefer not using LENR and using Darks instead though.



#4 BGazing

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Posted 17 July 2017 - 03:10 PM

Any chance with a good smartphone camera, say S8? Has maximum ISO of 800...wonder whether I could do a hyperlapse video...



#5 Astro Pike

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Posted 17 July 2017 - 03:12 PM

This might not be the time to master a new technique

I know, but you have to start at one point ;-)

Next Thursday and Friday the weather won't be good. 

I will study it carefully then!

Your info is very useful!

 

Probably a silly question: what if I only stack lights?

Will that make a difference?


Edited by Astro Pike, 17 July 2017 - 03:28 PM.

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#6 leveye

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Posted 17 July 2017 - 04:42 PM

First you want to try to get to the darkest locale possible first. Try single shots on a tripod try shooting with in camera noise reduction and high ISO NR turned off and the lens wide open using RAW and bulb mode for about 20-25 seconds at ISO 1600-2500 (experiment) for that camera 2500 may be a bit noisy but then just do a basic edit in Abobe camera RAW.

 

Here is a single shot example using the above settings.

 

 

Galaxy Beach Full (1 of 1).jpg.jpg


Edited by leveye, 17 July 2017 - 04:48 PM.

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#7 MCovington

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Posted 17 July 2017 - 04:47 PM

 

This might not be the time to master a new technique

I know, but you have to start at one point ;-)

Next Thursday and Friday the weather won't be good. 

I will study it carefully then!

Your info is very useful!

 

Probably a silly question: what if I only stack lights?

Will that make a difference?

 

There will be more noise specks, but it's worth doing.



#8 leveye

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Posted 17 July 2017 - 05:14 PM

 

This might not be the time to master a new technique

I know, but you have to start at one point ;-)

Next Thursday and Friday the weather won't be good. 

I will study it carefully then!

Your info is very useful!

 

Probably a silly question: what if I only stack lights?

Will that make a difference?

 

Will work but won't remove any noise. Unless your using a tracking mount and taking very long exposures with inherently more noise ( that would be a better reason for stacking) I'd just do single RAW shots without any noise reduction and simply do it later in post. Waiting for the camera to do the darks frames is no fun just from experience and IMHO. 


Edited by leveye, 17 July 2017 - 05:15 PM.


#9 leveye

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Posted 17 July 2017 - 05:26 PM

Another example of a single shot using no in camera NR and just edited in Camera RAW.

 

29847799431_e9ac3c6495_o.jpg


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#10 Astro Pike

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Posted 17 July 2017 - 07:37 PM

I just finished shooting . I took some 150 pictures.

Unfortunately there were low hanging clouds.

Here's a random pic (20 seconds iso 1600).

I also shot in raw.

 

20017770_1867555666899037_29635453033444

 

Tomorrrow I'll see if I can make it look better.

 

It's 2.30 am over here. Bed time!



#11 Astro Pike

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Posted 17 July 2017 - 07:51 PM

Wrong picture. Same as my opening post. I'll try again tomorrow.



#12 erictheastrojunkie

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Posted 18 July 2017 - 08:50 AM

 

 

This might not be the time to master a new technique

I know, but you have to start at one point ;-)

Next Thursday and Friday the weather won't be good. 

I will study it carefully then!

Your info is very useful!

 

Probably a silly question: what if I only stack lights?

Will that make a difference?

 

Will work but won't remove any noise. Unless your using a tracking mount and taking very long exposures with inherently more noise ( that would be a better reason for stacking) I'd just do single RAW shots without any noise reduction and simply do it later in post. Waiting for the camera to do the darks frames is no fun just from experience and IMHO. 

 

Stacking only lights won't remove noise? Huh? Stacking will improve SNR by "averaging" pixel to pixel noise variation over several exposures, it'll absolutely reduce overall image noise. What it won't do is remove hot/stuck pixels, which is the point of dark frames, pixels that have the same value in every image that are not true signal. For wide angle astro (especially nightscape stuff) there really is no point in doing the calibration frames, it just adds an incredible amount of extra work with little benefit to overall image quality. I use portable tracking mounts so I usually shoot at ISO 800, I don't even bother stacking anymore. 



#13 Traveler

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Posted 18 July 2017 - 11:01 PM

Just a reminder. Keep in mind that any advice on ISO rates is more camera depended nowadays. For example a Nikon D5300-D5600 is a so called Iso-less camera/sensor and will perform at its best at ISO 200-400. Just saying ISO 1600 without mention the Camera model is not the most good advice someone can give.

 

For the OP: Iso 1600 is a good value for your Canon 450D sensor.



#14 glend

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Posted 19 July 2017 - 01:41 AM

The problem with forum advice is you get a range of responses, some will be helpful, some not.  As a long time 450D owner, with a fully modded and cooled 450D, and a mono version, i have years of experience.  Do not shoot above ISO800 with a 450D, that is the optimal setting for that model. Sure it will shoot ISO1600 but you get more noise. As its summer there, thermal noise will build up the more subs you shoot. Turn off in camera noise reduction, you want to minimise settings that increase processor activity (and thus heat production). You can shoot darks and bias frames later. Flats imho are a waste of time with 450Ds for what your trying to do. Good luck.



#15 Astro Pike

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Posted 19 July 2017 - 06:58 AM

Thanks again for all the advice!

Yesterday we were blessed with clear skies again!

I'm really starting to like taking these pictures, but I still have a lot to learn!

I tried stacking pictures, but hopelessly failed. I also experimented with different shutter speeds.

 

Am I the only one who sometimes feels uncomfortable alone in the dark in the midlle of nowhere blush.gif ?

As a city dweller  I am not used to the sounds animals make at night lol.gif

Owls hooting, pigs squealing, bats flying inches from your face...

Don't even start me talking about the sound the wind makes blowing through a corn field.

Three deer coming out of the bushes nearly gave me a heart attack!

 

So yesterday I convinced my wife to accompany me wink.gif

I shot hundreds of pictures. Here's one with my wife sitting on a fence staring at the sky.

 

IMG_2173_zpspmcetwqa.jpg

 

I didn't edit the picture yet. It's jpeg, because photobucket won't allow me to upload cr2 files.

Next time I'll try shooting ISO800 and camera noise reduction turned off.


Edited by Astro Pike, 19 July 2017 - 07:01 AM.


#16 Traveler

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Posted 19 July 2017 - 08:02 AM

Nice picture. Have Fun in France Astro Pike!




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