Milkyway nightscapes

Still a lot of misinformation regarding camera settings in this thread, again, I HIGHLY recommend people read this tutorial series by Roger Clark. It's the most in depth and technically sound tutorial for night photography (from planning your shots all the way through processing them) on the internet. It gets thick with technical details at times, but once you understand it you'll think "why did I ever follow those other tutorials." I don't even know how many tutorials, videos, blogs and articles on this type of photography I've read, way too many to think about, nothing comes close to Clark's series in terms of quality and in-depth information. The only thing that's made such a large improvement in my astrophotography besides his tutorials was getting a skytracker mount.

http://clarkvision.com​/articles/nightscapes/

pdxbenedetti wrote in post #18064104
Still a lot of misinformation regarding camera settings in this thread, again, I HIGHLY recommend people read this tutorial series by Roger Clark. It's the most in depth and technically sound tutorial for night photography (from planning your shots all the way through processing them) on the internet. It gets thick with technical details at times, but once you understand it you'll think "why did I ever follow those other tutorials." I don't even know how many tutorials, videos, blogs and articles on this type of photography I've read, way too many to think about, nothing comes close to Clark's series in terms of quality and in-depth information. The only thing that's made such a large improvement in my astrophotography besides his tutorials was getting a skytracker mount.

http://clarkvision.com​/articles/nightscapes/

Having read that article I don't see the misinformation. The only difference is his article is geared towards using a tracker so lower iso and the 200 rule. For those that don't have a tracker high ISO and the 400 rule or 500 rule yields good results. You only have to look through this thread to see that. Or is that not the misinformation?

The misinformation is in regards to ISO suggestions mostly, you can take longer exposures, just depends on how much you care about star trailing. His work flow for processing and points on white balance are also very very good.

His tutorials are all inclusive, not geared towards tracking setups. He provides technical data backing up his recommendations and a thorough description for why he makes the suggestions he does. Not just "crank your ISO, buy an ultra wide angle lens and take a 30 second exposure."

pdxbenedetti wrote in post #18064136
The misinformation is in regards to ISO suggestions mostly, you can take longer exposures, just depends on how much you care about star trailing. His work flow for processing and points on white balance are also very very good.

His tutorials are all inclusive, not geared towards tracking setups. He provides technical data backing up his recommendations and a thorough description for why he makes the suggestions he does. Not just "crank your ISO, buy an ultra wide angle lens and take a 30 second exposure."

Apologies I just realised you can click on each section of that link and I was only viewing page 1 (was browsing on my phone there). Im still learning too so bear with me here but if I am shooting my lens wide open and I care about star trailing and therefore have a maximum shutter speed I can use then surely cranking up the ISO is the only variable left if I am not getting the exposure I want?. Thats why people will say things like "crank your ISO, buy an ultra wide angle lens and take a 30 second exposure."

This paragraph here from your link is an eye opener - "Pushing up in ISO to high levels only reduces dynamic range; there is no change in sensitivity. ISO is post sensor gain and all one needs to do to is get the gain high enough to amplify the signals from the sensor above the noise from post sensor electronics, including fixed pattern, or banding noise. With the Canon 5D2, that occurs at about ISO 3200. For the 1D4, it is at about ISO 1600. Figure 2 illustrates the effects. At ISOs below 1600 on the 5D2, post sensor electronics noise dominates above sensor read noise (gray band in Figure 2). Above ISO 1600, dynamic range is reduced in proportion to the increase in ISO. With the 5D2, a small amount of banding noise is evident in some images, so I usually use ISO 3200 for nightscapes. At this ISO (amplification) any under exposure can be adjusted in post processing with no added detriment to image quality because the signal and noise from the sensor is digitized adequately"

How would you work out the ISO that the gain is high enough to amplify the signals from the sensor above the noise from post sensor electronics, including fixed pattern, or banding noise?

Sorry, I'm at the airport about to get on my plane so I can't type out a response, but he discusses how to find the ISOless point for your camera in one of the sections. There's a website that has ISO information for doing that, www.sensorgen.info

pdxbenedetti wrote in post #18064176
Sorry, I'm at the airport about to get on my plane so I can't type out a response, but he discusses how to find the ISOless point for your camera in one of the sections. There's a website that has ISO information for doing that, www.sensorgen.info

Thanks, ill read more on his site and the link above.

pdxbenedetti wrote in post #18064136
"crank your ISO, buy an ultra wide angle lens and take a 30 second exposure."

In layman's terms without rewriting the Clark article: IE a paragraph for less. Tell us how you do it.

FEChariot wrote in post #18064280
In layman's terms without rewriting the Clark article: IE a paragraph for less. Tell us how you do it.

How about one sentence: not using my tracker with my Nikon D600, use a 24mm f1.4 lens for largest aperture possible, set aperture to f1.4, ISO 1600 (ISOless point for my camera) and take a 12-15 second exposure.

My reasoning:

The two single most important things for getting the highest quality Milky Way images are 1) clear aperture area and B) exposure time. Ultra wide angle lenses (think lenses between 10-20mm) don't offer large aperture areas, generally the largest is f2 or f2.8. The amount of light your lens collects is proportional to the aperture and focal length, the Tokina 11-16mm f2.8 (for example) has a clear aperture area of (11/2.8) which equals 3.92mm. The Rokinon 24mm f1.4 has a clear aperture area of (24/1.4) which equals 17.14mm, this means the Rokinon collects (17.14/3.92)^2 = 19 times as much light. So even though you COULD take a 54 second exposure (using the rule of 600 and not taking DSLR crop sensor factor into account) versus a 25 second exposure with the Rokinon without getting star trails you'd still be collecting 9 times as much light with the 25 second exposure from the Rokinon.

Astrophotography is all about collecting as much of the few photons of light at night as possible, to do that you need a lens with a wide aperture with a moderate focal length and you need to take as long as an exposure as possible. Everything else is digitization and manipulation of the signal after it's been converted by your sensor. ISO is a vestigial term from the days of film photography that literally means nothing for digital photography. People tend to have the idea that ISO still has some link to sensitivity (as in the days of film), it doesn't, all it is is a digital amplification of the post sensor signal by your camera. Every modern dslr camera will be the same, at some point the digital noise introduced by increasing ISO outweighs the signal noise from your sensor, that's the point you should stop increasing ISO. For most cameras these days that point is around ISO 800 or 1600, some of them up to 3200. Shooting higher than that point only decreases the dynamic range of your sensor which means you start clipping highlights (and the highlights in astro images are stars). Ever wonder why the majority of stars in most astro images are white instead of a wide variety of colors (blue, red, orange, yellow, and white)? It's because people are shooting at too high of an ISO point, clipping the stars highlights and the color data is lost. You're better off shooting at the ISOless point and then increasing exposure in post, doing that maintains dynamic range and doesn't introduce any more noise than just increasing ISO.

If you truly want the highest quality astrophotography images you should buy a tracker so you can actually collect long exposures at low ISO. Think of it this way, a lot of people spend thousands of dollars on equipment for this hobby, you can spend probably a third of what you'd normally spend, buy the Rokinon 24mm f1.4 lens for $500 and an iOptron Skytracker for $300 and produce significantly better results. I kind of laugh thinking about all the money I've spent on photography equipment for this hobby on various lenses and other things, now I pretty much only use one lens for widefield (the 24mm), one lens for slightly zoomed portions of the sky/landscapes (85mm f1.4) and my 150-600mm monster for deep space stuff. Pretty much all my other half dozen lenses are now collecting dust unless I want to use them for non-astro purposes. Plus now instead of taking 200+ shots at night I take maybe 40 shots and I use all of them, much less hard drive space taken up and much less sifting through tons of shots to find the best ones. I never shoot above ISO 800 anymore and I can stop down to f2-f3 to get round stars with a star burst affect thanks to the aperture blades, then take 1-5 minute exposures.

This is just my reasoning, there's more than one way to skin a cat and people are producing quality astro images doing it other ways, but I truly believe that the best image quality (in terms of noise levels, detail, natural looking, accuracy, etc) is produced with the method I described.

Assuming the section of sky is "due south" and the camera was oriented so that "north is up" then you're getting the stars smearing along the declination axis. That indicates that your azimuth was not correct when you aligned the mount (it wasn't really pointed to true north).

(Note: This was in response to Inspeqtor's post of the image of the sky while on a tracking mount, but unable to get a good alignment due to no clear view to the north from his location.)

pdxbenedetti wrote in post #18064351
How about one sentence: not using my tracker with my Nikon D600, use a 24mm f1.4 lens for largest aperture possible, set aperture to f1.4, ISO 1600 (ISOless point for my camera) and take a 12-15 second exposure.

My reasoning:

The two single most important things for getting the highest quality Milky Way images are 1) clear aperture area and B) exposure time. Ultra wide angle lenses (think lenses between 10-20mm) don't offer large aperture areas, generally the largest is f2 or f2.8. The amount of light your lens collects is proportional to the aperture and focal length, the Tokina 11-16mm f2.8 (for example) has a clear aperture area of (11/2.8) which equals 3.92mm. The Rokinon 24mm f1.4 has a clear aperture area of (24/1.4) which equals 17.14mm, this means the Rokinon collects (17.14/3.92)^2 = 19 times as much light. So even though you COULD take a 54 second exposure (using the rule of 600 and not taking DSLR crop sensor factor into account) versus a 25 second exposure with the Rokinon without getting star trails you'd still be collecting 9 times as much light with the 25 second exposure from the Rokinon.

Astrophotography is all about collecting as much of the few photons of light at night as possible, to do that you need a lens with a wide aperture with a moderate focal length and you need to take as long as an exposure as possible. Everything else is digitization and manipulation of the signal after it's been converted by your sensor. ISO is a vestigial term from the days of film photography that literally means nothing for digital photography. People tend to have the idea that ISO still has some link to sensitivity (as in the days of film), it doesn't, all it is is a digital amplification of the post sensor signal by your camera. Every modern dslr camera will be the same, at some point the digital noise introduced by increasing ISO outweighs the signal noise from your sensor, that's the point you should stop increasing ISO. For most cameras these days that point is around ISO 800 or 1600, some of them up to 3200. Shooting higher than that point only decreases the dynamic range of your sensor which means you start clipping highlights (and the highlights in astro images are stars). Ever wonder why the majority of stars in most astro images are white instead of a wide variety of colors (blue, red, orange, yellow, and white)? It's because people are shooting at too high of an ISO point, clipping the stars highlights and the color data is lost. You're better off shooting at the ISOless point and then increasing exposure in post, doing that maintains dynamic range and doesn't introduce any more noise than just increasing ISO.

If you truly want the highest quality astrophotography images you should buy a tracker so you can actually collect long exposures at low ISO. Think of it this way, a lot of people spend thousands of dollars on equipment for this hobby, you can spend probably a third of what you'd normally spend, buy the Rokinon 24mm f1.4 lens for $500 and an iOptron Skytracker for $300 and produce significantly better results. I kind of laugh thinking about all the money I've spent on photography equipment for this hobby on various lenses and other things, now I pretty much only use one lens for widefield (the 24mm), one lens for slightly zoomed portions of the sky/landscapes (85mm f1.4) and my 150-600mm monster for deep space stuff. Pretty much all my other half dozen lenses are now collecting dust unless I want to use them for non-astro purposes. Plus now instead of taking 200+ shots at night I take maybe 40 shots and I use all of them, much less hard drive space taken up and much less sifting through tons of shots to find the best ones. I never shoot above ISO 800 anymore and I can stop down to f2-f3 to get round stars with a star burst affect thanks to the aperture blades, then take 1-5 minute exposures.

This is just my reasoning, there's more than one way to skin a cat and people are producing quality astro images doing it other ways, but I truly believe that the best image quality (in terms of noise levels, detail, natural looking, accuracy, etc) is produced with the method I described.

So what if 24mm is not wide enough to capture the scene as you want it framed? Do you just stitch more images together? Then why stop there? Why not just buy a 600/4 IS II to get the maximum clear aperture available and just stitch 87 images together or whatever the math works out to be?

There is some point where too much is too much. Otherwise every macro shot short of this:

http://petapixel.com …captured-microscope-lens/

Would be considered "miss information"?

Also, tracking is great, but be prepared to do some PS work if you want to include a stationary foreground while you are tracking the sky. Then again if someone doesn't want to do a multi shot panorama would you consider it "miss information? doing it wrong?

FEChariot wrote in post #18064407
So what if 24mm is not wide enough to capture the scene as you want it framed? Do you just stitch more images together? Then why stop there? Why not just buy a 600/4 IS II to get the maximum clear aperture available and just stitch 87 images together or whatever the math works out to be?

There is some point where too much is too much. Otherwise every macro shot short of this:

http://petapixel.com …captured-microscope-lens/

Would be considered "miss information"?

Also, tracking is great, but be prepared to do some PS work if you want to include a stationary foreground while you are tracking the sky. Then again if someone doesn't want to do a multi shot panorama would you consider it "miss information? doing it wrong?

The difference between 24mm and (say) 14mm is not significant, you really have trouble stitching images? 24mm is pretty dang wide and the time you save by taking shorter exposures means you can take more exposures and cover way more sky. Of all the steps in post processing, stitching probably takes the least amount of time. You're making WAY too much out of this and the 600mm "metaphor" is a real eye roller, nice exaggeration to try and prove a point. This is a stitched image with my D600 and 24mm lens on the iOptron skytracker, 1 row of 6 images wide for the sky, 1 row of 6 images for the foreground which covers almost 180 degrees:

Of course the 600/4 comment was ridiculous but its point is to counter another ridiculous comment that using an UWA is misinformation. Why not use a Sigma 50/1.4 EX? It provides 4.3 times more light than the 24/1.4? By your logic it is as equally misinformed to use the 24/1.4 over that 50/1.4. But then where does it end? 85/1.4 lets in more light: 135/2 lets in more light, 200/2.8 lets in more light, 300/2.8, 400/2.8 and so on.

24mm probably would be great for me if there was an economical full frame camera that could do what my 7D can do in the other aspects of photography I do. So that means 24mm is just not wide enough. And seeing how there is no 15/1.4 for crop, what are other crop users and myself to do?

As to color temperature of the sky, you and Mikey are probably to best two posters on this thread and you both use different color temp. Does that take away from his images? Not in my opinion.

As far as stitching tracked and untracked images together, the only way I know to do it is to mask out the tracked group Ground layer and which mean selecting the ground layer and feathering it out to get it right. That is about right up there with stapling my testicles to a wood bench in the list of my favorite things to do. If you have a better way then I would love to see a tutorial. My PS skills are not what many others are.

Oh and for the record, I think there is a significant difference between 14mm and 24.

I really love these images and wish I had the time and location to do my own

mikepj wrote in post #18063995
Are you just eyeballing the placement, or are you using a compass (on your phone or otherwise)? Make sure you correct for declination between magnetic north and true north (which is what it should be aligned to).

http://www.ngdc.noaa.g​ov/geomag/declination.​shtml

There is a built in compass on the iOptron Star Tracker I have been using.