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05-30-2021, 11:02 AM   #1
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Need advice: Star Trails and Milky Way Wide Field Planned First Attempts

Thanks to those who provided advice re: my attempts at lunar eclipse stacking!

I need more astrophotography help.

Again, I am a beginner with these techniques.

Next weekend, I will be camping at a couple great dark sky spots in the remote Sierra Nevada mountains here in California. I would like to try a star trails shot and a wide-field milky way shot. I will be using my K-1ii and my D-FA 24-70mm f/2.8 lens and the Astrotracer function.

I have read several approaches to both of these shots, so I am confused. For the milky way shot, I have read that an EV of -8 is required. Is this correct? would I get better results at an EV of -7 or -6 due to presumably decreased noise? Should I favor a long exposure or a low ISO to get the best result? Should I stack exposures? Should I take dark frames, or use the long-exposure NR in-camera? I am also considering whether it is best to shoot one frame at 24mm or 3 or 4 frames at 35mm and stich them (vertically) in post.

For the star trails shot, everything I read suggests 30-second exposures. Is there any reason that I can't use a longer exposure, like 1 minute? Is it because the stars will effectively "move out" of a given pixel before that pixel is fully exposed? I am thinking of doing a 2-hour total exposure. What is the proper EV to use for this? I have read that -7 is good, but that is so close to the recommended exposure for the milky way shot that I wonder if -6, -5 or -4 would be better. Please advise! Should I use the star trails function in-camera or combine exposures later in post?

I note that I will only have one try at the star trails shot for each location where I will be camping. I can try a couple different approaches for the milky way shot.

At location #1, they view is likely to be towards the NNE, at location #2, the view is likely to be toward the E.

I will probably shoot my foreground earlier in the evening.

In anticipation of your responses, thank you!

~ Jon

05-30-2021, 01:43 PM - 1 Like   #2
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Star trails are much more forgiving exposure-wise than the Milky Way.

Milky Way tips:
  • Don't worry too much about EV. I suggest starting the night with an educated guess at exposure, then take a test shot and examine it to see if you need to adjust settings.
    • At 24mm f2.8, I would use 3200 ISO, 20 second shutter for my first test shot. (although anywhere from 1600 to 6400 ISO can give similar results; lower ISO gives less initial noise, but you'll need to lift shadows more which adds that noise back in)
    • Zoom all the way in to the test shot to check focus, star trailing, and tripod vibration. A little bit of trailing is okay; you won't notice it at normal viewing sizes.
    • Check the histogram. Make sure it's not too far to the left with completely clipped blacks. A histogram peak approx. 1/3 of the way from the left is a common suggestion.
  • I suggest not stacking/stitching your first Milky Way shots. You already have enough to learn with composition and exposure.
  • The brightest portion of the Milky Way from the northern hemisphere is to the south, in the direction of the constellation Sagittarius. Compositions to the north can still work, but try a shot to the south for comparison.
  • Check moon phase in advance. On moonless nights, feature the Milky Way. On moonlit nights, get an interesting ground feature lit up, and expect the Milky Way to be washed out.
Star trails are IMO more forgiving than the Milky Way.
  • You asked whether 1 minute exposures are okay. Yes, they are. 30 seconds is a more common recommendation I think just because that's frequently the longest exposure allowed on some camera models.
  • If you have 2 hours to do star trails, I suggest 2 different 1-hour compositions, in different directions and with different landscape elements.
  • Make sure to use settings that minimize gaps between exposures. While the 2-second timer is great for the Milky Way to reduce vibration, don't use that if it will give you a 2-second gap in every star trail frame.
  • The free software StarStax is one of the easiest ways to combine exposures. There are many other ways to do it, though, including in-camera, other free software, or Photoshop layering.
  • I prefer to not use in-camera stacking for star trails. Software stacking gives you more flexibility, and you can reprocess old photos as you get better with processing. For example, if you have unwanted aircraft light trails in your star trail stack, you can do a simple processing and leave them in for now, then learn how to erase the aircraft later.
05-30-2021, 02:36 PM   #3
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QuoteOriginally posted by DeadJohn Quote
Star trails are much more forgiving exposure-wise than the Milky Way.

Milky Way tips:
  • Don't worry too much about EV. I suggest starting the night with an educated guess at exposure, then take a test shot and examine it to see if you need to adjust settings.
    • At 24mm f2.8, I would use 3200 ISO, 20 second shutter for my first test shot. (although anywhere from 1600 to 6400 ISO can give similar results; lower ISO gives less initial noise, but you'll need to lift shadows more which adds that noise back in)
    • Zoom all the way in to the test shot to check focus, star trailing, and tripod vibration. A little bit of trailing is okay; you won't notice it at normal viewing sizes.
    • Check the histogram. Make sure it's not too far to the left with completely clipped blacks. A histogram peak approx. 1/3 of the way from the left is a common suggestion.
  • I suggest not stacking/stitching your first Milky Way shots. You already have enough to learn with composition and exposure.
  • The brightest portion of the Milky Way from the northern hemisphere is to the south, in the direction of the constellation Sagittarius. Compositions to the north can still work, but try a shot to the south for comparison.
  • Check moon phase in advance. On moonless nights, feature the Milky Way. On moonlit nights, get an interesting ground feature lit up, and expect the Milky Way to be washed out.
Thank you!
  • You're right, I can afford to test my exposure and adjust. I was just concerned that the preview on the rear screen won't give me a good idea of the RAW data that I will ultimately be working with in post.
  • Why should I limit myself to 20 sec. exposure? Won't Astrotracer give me 3-4 minutes to work with?
  • Excellent advice on checking focus in the final image! Do I need a Bahtinov mask for initial focusing, or will zooming in on live view and minimize star size be enough?
  • Thanks for the tip on histogram peak! I have not seen this anywhere else.
  • I think I can afford to try single frame shots and stacking and/or stitching. The time commitment to collect the various frames is minimal compared to my planned star trails shot. Would stacking or collection of dark/flat frames yeild better results?
  • Yeah, at Location #1 I won't have good foreground for shooting south. There may be better options at Location #2.
  • I have checked using Stellarium, and the moon is at 13% and won't be rising until nearly 4:00 a.m., so I think I am good there.


QuoteOriginally posted by DeadJohn Quote
Star trails are IMO more forgiving than the Milky Way.
  • You asked whether 1 minute exposures are okay. Yes, they are. 30 seconds is a more common recommendation I think just because that's frequently the longest exposure allowed on some camera models.
  • If you have 2 hours to do star trails, I suggest 2 different 1-hour compositions, in different directions and with different landscape elements.
  • Make sure to use settings that minimize gaps between exposures. While the 2-second timer is great for the Milky Way to reduce vibration, don't use that if it will give you a 2-second gap in every star trail frame.
  • The free software StarStax is one of the easiest ways to combine exposures. There are many other ways to do it, though, including in-camera, other free software, or Photoshop layering.
  • I prefer to not use in-camera stacking for star trails. Software stacking gives you more flexibility, and you can reprocess old photos as you get better with processing. For example, if you have unwanted aircraft light trails in your star trail stack, you can do a simple processing and leave them in for now, then learn how to erase the aircraft later.

Thanks again!
  • Is there any advantage or disadvantage to longer exposures? Will it allow me to use base ISO to reduce noise? Should I take dark frames for use in post or will the blending of all these exposures for the star trails eliminate my noise (and hot pixel) problems? I will need to use an external intervalometer for exposures longer than 30 seconds, I think.
  • I was just thinking 2 hours because I like the look of the 2-hour exposures I am seeing online, not because that is my only time window. Location #2 might have more varied landscape elements for me to draw from. Location #1 is more limited - there is a sole interesting feature and limited vantage points. I am making another trip to the mountains in July, so will have a chance to practice again then.
  • Thanks! I will check out StarStax. I don't think I have run across this name yet.
  • Very good point. I think that the individual exposures are *not* saved when doing this in-camera, correct? Yeah, that would give me zero options to work with it later in StarStax or anther post-processing program.
05-30-2021, 03:58 PM - 2 Likes   #4
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QuoteOriginally posted by jon.partsch Quote
will zooming in on live view and minimize star size be enough?
That's the way to do it - when you are dead on, the stars almost disappear. If there are bright (human-based!) lights off in the distance, that works, too. Make sure you are on manual focus - there is nothing quite so maddening as getting the focus just right, then hitting the shutter button, and hearing the autofocus whine into operation! Practice this at home before you leave - much less nerve-wracking than worrying about missing your big opportunity while out in the boonies.

QuoteOriginally posted by jon.partsch Quote
Would stacking or collection of dark/flat frames yeild better results?
For ordinary/nice pictures (i.e. not photometry or the absolute in perfection), forget about darks/flats. At least until later, and practice that stuff at home, too, when you are not under any kind of time pressure.

QuoteOriginally posted by jon.partsch Quote
I will need to use an external intervalometer for exposures longer than 30 seconds, I think.
Good idea. If you wind up using the internal intervalometer for shorter exposures, don't forget that a "30" second exposure is really "32" seconds (and a "15" is real;y 16)! I think there is now a mode to just take the next picture as soon as the previous one finishes, but in the older cameras, you had to tell it the interval between exposure starts, and it you put in, say, 31 seconds while using "30 second" exposures, you missed every other interval!

ps Where are you going in the Sierra? I've spent a lot of time on the east side of the Sierra (Owens Valley), back to when I was a radio astronomy grad student at Caltech. The Caltech radio observatory is between Big Pine and Bishop. --> lots of trips between Pasadena and Big Pine. And, lots of side trips up the mountains from Lone Pine, Independence, Big Pine, and Bishop.

05-30-2021, 04:27 PM   #5
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QuoteOriginally posted by AstroDave Quote
That's the way to do it - when you are dead on, the stars almost disappear. If there are bright (human-based!) lights off in the distance, that works, too. Make sure you are on manual focus - there is nothing quite so maddening as getting the focus just right, then hitting the shutter button, and hearing the autofocus whine into operation! Practice this at home before you leave - much less nerve-wracking than worrying about missing your big opportunity while out in the boonies.
Yes, Indeed! When I was photographing the eclipse last week, I also noted that a bump to the camera can also throw the focus off. I was all set up, but didn't have the tilt knob on my tripod head tightened, so the head tilted down to it's limit with and hit its hard stop rather abruptly. It was a good call that I re-checked my focus after getting my composition dialed in again, because it was definitely off.


QuoteOriginally posted by AstroDave Quote
For ordinary/nice pictures (i.e. not photometry or the absolute in perfection), forget about darks/flats. At least until later, and practice that stuff at home, too, when you are not under any kind of time pressure.
I plan to collect my star trails first, and then the milky way last as it won't rise into view from my vantage point for a couple hours. I should have plenty of time after collecting my lights for the milky way to collect darks, and I can do flats the next day. I don't see there being any time-pressure involved, and I can have them if needed and experiment with them in post. I don't see a need to collect a ton of them. I was thinking 8 or 16 (I read that increasing benefit requires a logarithmic (square function) increase in frames).


QuoteOriginally posted by AstroDave Quote
Good idea. If you wind up using the internal intervalometer for shorter exposures, don't forget that a "30" second exposure is really "32" seconds (and a "15" is real;y 16)! I think there is now a mode to just take the next picture as soon as the previous one finishes, but in the older cameras, you had to tell it the interval between exposure starts, and it you put in, say, 31 seconds while using "30 second" exposures, you missed every other interval!
I have read about the counter-intuitive nature of the built-in intervalometer, so I am a bit nervous to use it, but of course, I can practice this at home in the daylight too. An external intervalometer has other benefits as a shutter release cable too, so that I don't even have to touch the camera after setting up the shot.

QuoteOriginally posted by AstroDave Quote
ps Where are you going in the Sierra? I've spent a lot of time on the east side of the Sierra (Owens Valley), back to when I was a radio astronomy grad student at Caltech. The Caltech radio observatory is between Big Pine and Bishop. --> lots of trips between Pasadena and Big Pine. And, lots of side trips up the mountains from Lone Pine, Independence, Big Pine, and Bishop.
I think the schedule is to be at Cherry Lake for two nights and then in Yosemite Valley for two nights. The eastern sierra (Mono Lake, June Lake, Bodie, etc.) is my favorite area on planet earth so far. I have been out there many times, unfortunately my SO isn't as excited about the desert as I am. We will be camping in Lassen in July also, so I plan to practice some more astrophotography then.

~ Jon
05-30-2021, 04:43 PM - 1 Like   #6
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Another hint; Include some of the foreground scenery in your shots. Yosemite is a great opportunity to do this if your Sierra trip takes you that way.. You might have to combine two exposures, one with the Astrotracer on and one with it off (for the foreground which it will blur if tracking the stars). Those two exposures (foreground and sky) might have to be different also to properly render them which is another reason to break the shot into two exposures. Just mention this so you don't get home and have only sky shots (which are nice but you can really "spice" them up with a touch of foreground included - especially if it's El Capitan or the like).
05-30-2021, 05:50 PM - 1 Like   #7
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QuoteOriginally posted by jon.partsch Quote
Why should I limit myself to 20 sec. exposure? Won't Astrotracer give me 3-4 minutes to work with?
20 seconds is if you want foreground plus untrailed stars in same shot. You are correct that astrotracer can go much longer, but then the foreground blurs which adds processing complexities.


QuoteOriginally posted by jon.partsch Quote
Do I need a Bahtinov mask for initial focusing, or will zooming in on live view and minimize star size be enough?
Liveview zoom is what I use most of the time. Bahtinov mask is IMO not for wide angle; it's more of a tool for 300mm+.


QuoteOriginally posted by jon.partsch Quote
Is there any advantage or disadvantage to longer exposures? Will it allow me to use base ISO to reduce noise?
Longer exposures are usually better (less noisy, fewer frame to process) for both Milky Way and star trails. The longer you go, though, increases the risk of unwanted star trailing for the Milky Way. Even with star trails it's possible to go too long if the sky background causes overexposure but that's more of a problem when there's light pollution.


QuoteOriginally posted by jon.partsch Quote
Should I take dark frames for use in post or will the blending of all these exposures for the star trails eliminate my noise (and hot pixel) problems?
Dark frames aren't needed for star trails since you'll be stacking. They don't hurt, but remember that dark frames need to be taken near the same temperature as the photos, so it's best to take them after your light frames when the camera has warmed up. Simple noise reduction software, without dark frames, is IMO adequate to deal with hot pixels.
05-30-2021, 07:09 PM   #8
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QuoteOriginally posted by Bob 256 Quote
Another hint; Include some of the foreground scenery in your shots. Yosemite is a great opportunity to do this if your Sierra trip takes you that way.. You might have to combine two exposures, one with the Astrotracer on and one with it off (for the foreground which it will blur if tracking the stars). Those two exposures (foreground and sky) might have to be different also to properly render them which is another reason to break the shot into two exposures. Just mention this so you don't get home and have only sky shots (which are nice but you can really "spice" them up with a touch of foreground included - especially if it's El Capitan or the like).
Yes, I will be in Yosemite. I am planning to use Astrotracer and shoot the foreground separately, probably during dusk.


QuoteOriginally posted by DeadJohn Quote
20 seconds is if you want foreground plus untrailed stars in same shot. You are correct that astrotracer can go much longer, but then the foreground blurs which adds processing complexities.
Taking a separate exposure for my forground landscape was always part of my plan. Sorry if I did not make that clear in my original post.

QuoteOriginally posted by DeadJohn Quote
Liveview zoom is what I use most of the time. Bahtinov mask is IMO not for wide angle; it's more of a tool for 300mm+.
Okay, that's good to know - one less thing to worry about.

QuoteOriginally posted by DeadJohn Quote
Longer exposures are usually better (less noisy, fewer frame to process) for both Milky Way and star trails. The longer you go, though, increases the risk of unwanted star trailing for the Milky Way. Even with star trails it's possible to go too long if the sky background causes overexposure but that's more of a problem when there's light pollution.
There should be zero light pollution. My plan is to shoot the foreground separately. I can shoot a long exposure and check for star trailing and adjust if needed. This sounds like the way to go. I can also shoot a few dark frames at the end for good measure.

QuoteOriginally posted by DeadJohn Quote
Dark frames aren't needed for star trails since you'll be stacking. They don't hurt, but remember that dark frames need to be taken near the same temperature as the photos, so it's best to take them after your light frames when the camera has warmed up. Simple noise reduction software, without dark frames, is IMO adequate to deal with hot pixels.
My idea of using dark (ad possibly flat frames) is for the milky way shot, not for the star trails shot. Yes, my understanding is that they are not needed for a big stack like the star trails because the stack will "average out" the noise. I also would imagine that hot pixels can be more easily dealt with in a star trails photo. I have not been able to eliminate hot pixels with noise redacting in Lightroom in the past - they have been greatly vexing to me in any exposures more than a few seconds in length - both with my K-5 and with my K-1ii. I hate them.

~ Jon

05-30-2021, 10:15 PM - 2 Likes   #9
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A couple of other points to keep in mind:-

Startrails - these can be taken using quite small apertures and quite low ISO's. You can comfortably get good results around ISO400 with apertures around F4 to F7.1. Maintaining good star colour and thin trails is helped by not overdoing the exposure. You should be able to set your K-1 II's intervalometer to run timed B mode exposures of more than 30 seconds and set the interval to "minimum" to minimise gaps. The stacking software (starstax or startrails) has a setting to close up the gaps.

Foreground/astrotracer blending - is not always just a matter of a still shot and an astrotracer shot. If you go with a long astrotracer sky exposure, the thick blurred line at the horizon is difficult to blend with the sharp line you get from the foreground shot - unless you shift one or the other. The second problem is the difference in ambient sky colour/exposure. This can be very frustrating to blend in Postprocessing.

A good fall back plan is to take plenty of short frames without the astrotracer and then use Sequator which will stack the stars and freeze the foreground. Quick and easy to do and you will have a fall back option if the postprocessing proves challenging. Around 3 to 4 minutes of exposure time for the stars at f2.8 should be enough in a dark sky area.


On a dark night, you will need about 4 times the exposure for the foreground - stacking again is a good way to minimise noise before blending.


My last tip is to set up user modes before you leave home and test them to make sure they are doing what you expect. It saves all the mucking around with Hi ISO NR, intervalometer settings, WB and anything else. One flick of the wheel and you know you are ready to go - and didn't forget to change something that you only find out when you are back at the computer - don't ask how I know.


Good luck and clear skies as the say!
05-31-2021, 12:43 AM - 1 Like   #10
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I use the Photo Pills app on my iPad to help plan shoots. One of the great things is they provide a whole bunch of free PDF documentation on different subjects.
Here is a link to the free "Milky Way Photography: The Definitive Guide (2021)"
They are Pentax friendly as they even mention the Pentax K-70, KP & K1 Mark2.
Page 2 & 4 has links to other more specific guides.
The OP should download it and have a read.
05-31-2021, 12:07 PM - 1 Like   #11
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I would suggest to try some constellations as well. With an astrotrace these are very easy to do. The main issue is to locate them. But you do not have to fiddle with the foreground. Use a 50 mm or a 35 mm for a wider field of view. With the stellarium programm for pc, you can look up in advance witch constellations you will be seeing and which focal length you need.
05-31-2021, 01:28 PM - 1 Like   #12
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One other tiny thing that you can do right now is to remove hot pixels, tools page 4 - pixel mapping.
05-31-2021, 06:40 PM - 1 Like   #13
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The k1 should easily handle an ISO of 3200 or 6400. For the Milky Way, I keep the high ISO and long exposure noise reduction on. Most lenses are soft wide open so stop the lens down stops a couple of clicks to sharpen the pinpoint stars. For a little extra stability (and for safety's sake) set a gallon jug of water under the tripod and use a bungee cord or light twine to tie the tripod to the jug of water. It will keep it from shaking in the breeze or gusts from toppling the camera and it's less likely you'll accidentally knock the camera over in the dark. Been there. Done that. It sucks. Turn off autofocus and auto exposure. I think the camera has to be in the 'B' or 'Manual' mode for Astrotracer to function. Check the instruction manual.
For star trails, I usually do five minute exposures and about a 400 ISO and stack them with Startrails program. Turn off high ISO and long exposure noise reduction. Changing exposure time won't affect the brightness or number of the star trails. It will only change how long the trails are. Lowering ISO or decreasing the aperture will decrease the number of trails and the converse is true. Higher ISO/wider aperture = more/brighter star trails.
For night photography a remote shutter release really is needed. If you don't already have on you can use the two second self timer temporarily. For star trails, an intervalometer like the Shutterboss will let you get consistent exposures longer than 30 seconds. You'll learn how hard that is to do when you start doing star trails.
The next meteor shower isn't until late July so I won't go there yet. There's more that doesn't come to mind right now but I'll try to add more as I remember it.

Oh! I know. There's a lot of post processing videos on YouTube that will help with after you get the images. just search for the keywords "Milky Way" and "post processing"












06-01-2021, 11:53 AM - 1 Like   #14
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QuoteOriginally posted by Grimmus Quote
Startrails - these can be taken using quite small apertures and quite low ISO's. You can comfortably get good results around ISO400 with apertures around F4 to F7.1. Maintaining good star colour and thin trails is helped by not overdoing the exposure. You should be able to set your K-1 II's intervalometer to run timed B mode exposures of more than 30 seconds and set the interval to "minimum" to minimise gaps. The stacking software (starstax or startrails) has a setting to close up the gaps.
Yes, I was wondering what is the best exposure value to use to get (1) thin lines, (2) good color in the trails, and (3) maximize number of trails. The way I see it, there is no option for trial and error, so I need to decide on the EV that I will use and hope for the best. This is one of my primary concerns. Also, I don't see a way to use the K-1ii internal intervalometer for exposures longer than 30 seconds. If there is a way to do this, please explain.

QuoteOriginally posted by Grimmus Quote
Foreground/astrotracer blending - is not always just a matter of a still shot and an astrotracer shot. If you go with a long astrotracer sky exposure, the thick blurred line at the horizon is difficult to blend with the sharp line you get from the foreground shot - unless you shift one or the other. The second problem is the difference in ambient sky colour/exposure. This can be very frustrating to blend in Postprocessing.
My plan was to shift the frames to cover the blurred foreground with my sharp foreground exposure.

QuoteOriginally posted by Grimmus Quote
A good fall back plan is to take plenty of short frames without the astrotracer and then use Sequator which will stack the stars and freeze the foreground. Quick and easy to do and you will have a fall back option if the postprocessing proves challenging. Around 3 to 4 minutes of exposure time for the stars at f2.8 should be enough in a dark sky area.
This is confusing to me. Are you saying that Sequator will basically shift the starts in each exposure so that they all line up, but will *not* also shift the foreground? If so this is interesting, and I may want to try this approach. It sound like it may be difficult to implement this along with additional offset frames intended for a stitched panorama. Are you suggesting this as an alternative approach to a single frame milky way scene *not* using Astrotracer?

QuoteOriginally posted by Grimmus Quote
On a dark night, you will need about 4 times the exposure for the foreground - stacking again is a good way to minimise noise before blending.
Thanks!

QuoteOriginally posted by Grimmus Quote
My last tip is to set up user modes before you leave home and test them to make sure they are doing what you expect. It saves all the mucking around with Hi ISO NR, intervalometer settings, WB and anything else. One flick of the wheel and you know you are ready to go - and didn't forget to change something that you only find out when you are back at the computer - don't ask how I know.
This is an excellent suggestion! I have not explored user modes yet, but I did change a lot of settings in preparation for my lunar eclipse photos, so I will look into this. Thanks, Grimmus!



QuoteOriginally posted by DeKay Quote
I use the Photo Pills app on my iPad to help plan shoots. One of the great things is they provide a whole bunch of free PDF documentation on different subjects.
Here is a link to the free "Milky Way Photography: The Definitive Guide (2021)"
They are Pentax friendly as they even mention the Pentax K-70, KP & K1 Mark2.
Page 2 & 4 has links to other more specific guides.
The OP should download it and have a read.
Thanks, DeKay! I have now read the entire document and have it saved on my phone, there are a few good tips in here for sure that I hadn't considered.


QuoteOriginally posted by Papa_Joe Quote
I would suggest to try some constellations as well. With an astrotrace these are very easy to do. The main issue is to locate them. But you do not have to fiddle with the foreground. Use a 50 mm or a 35 mm for a wider field of view. With the stellarium programm for pc, you can look up in advance witch constellations you will be seeing and which focal length you need.
Thanks Papa_Joe! I have stellarium on my phone. Is the PC version substantially different?

QuoteOriginally posted by Kevin B123 Quote
One other tiny thing that you can do right now is to remove hot pixels, tools page 4 - pixel mapping.
Thanks, Kevin B! I had completely forgotten about this function.

QuoteOriginally posted by gifthorse Quote
The k1 should easily handle an ISO of 3200 or 6400. For the Milky Way, I keep the high ISO and long exposure noise reduction on. Most lenses are soft wide open so stop the lens down stops a couple of clicks to sharpen the pinpoint stars. For a little extra stability (and for safety's sake) set a gallon jug of water under the tripod and use a bungee cord or light twine to tie the tripod to the jug of water. It will keep it from shaking in the breeze or gusts from toppling the camera and it's less likely you'll accidentally knock the camera over in the dark. Been there. Done that. It sucks. Turn off autofocus and auto exposure. I think the camera has to be in the 'B' or 'Manual' mode for Astrotracer to function. Check the instruction manual.
For star trails, I usually do five minute exposures and about a 400 ISO and stack them with Startrails program. Turn off high ISO and long exposure noise reduction. Changing exposure time won't affect the brightness or number of the star trails. It will only change how long the trails are. Lowering ISO or decreasing the aperture will decrease the number of trails and the converse is true. Higher ISO/wider aperture = more/brighter star trails.
For night photography a remote shutter release really is needed. If you don't already have on you can use the two second self timer temporarily. For star trails, an intervalometer like the Shutterboss will let you get consistent exposures longer than 30 seconds. You'll learn how hard that is to do when you start doing star trails.
The next meteor shower isn't until late July so I won't go there yet. There's more that doesn't come to mind right now but I'll try to add more as I remember it.

Oh! I know. There's a lot of post processing videos on YouTube that will help with after you get the images. just search for the keywords "Milky Way" and "post processing"
Thanks for all this, gifthorse! I am not worried about stability as I plan to bring a very heavy tripod with me, but will consider weighting it also. For startrails at ISO 400, what aperture are you using? I want to keep color in the trails, but maximize the number of trails that I can pick up. What stacking method do you use in post? Is it "brightest" method? Does that effectively eliminate long-exposure noise?

I am camping again in late July, so I'll try to catch the Southern Delta Aquariids / Alpha Capricornids. Thanks for the tip!

As for YouTube videos - yeah, I am totally comfortable learning the finer points of PP later on. I just want to make sure I collect the best exposures when I am in the field. complicated PP does not scare me. I can learn.


~ Jon
06-01-2021, 05:20 PM - 1 Like   #15
Pentaxian




Join Date: Dec 2011
Location: Nevada
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Posts: 2,225
For an initial set up for wide field Milky Way, leave the high ISO and the long exposure noise reduction on. Turn off the auto focus. I'd start with an ISO of 1600. I'm not familiar with the D-FA 24-70 so I'd set the aperture stopped down 1 or 2 clicks (not full stops, just a click or two) from wide open. With the Astrotracer, I'd start with an exposure time of about 2 minutes. If possible, aim the camera to the South. The galactic center, the brightest part of the Milky Way, will be low in the southern sky and will rise at around 10 pm. Check the exposure. If it's overexposed, I'd decrease the ISO and try again. If underexposed, I'd increase the exposure time first and then increase the ISO if needed. The Moon will rise around 3:30 am and will be about 10% to 20% illuminated. That should illuminate the foreground without washing out the Milky Way too badly.That's a start, but be prepared to make adjustments.
For star trails, I'd start with an ISO of 800. For maximum stars you'll want the lens wide open. Turn off the high ISO and the long exposure noise reduction and auto focus. Aiming the camera north, toward the North star, will give you shorter and more curved star trails. Aiming East or West will create longer and straighter trails. If you are doing 5 minute exposures, the Moon above the horizon will wash out the sky. For star trails, I use a freeware program called Startrails. It's easy to use.
What you see in the sky won't look like the images you take. The camera captures a lot more than your eyes see. The sky glow in the center of my first image is a small city some 30 miles away. The glow isn't visible with the naked eye but shows in long exposures. As you get more practice it will get easier.
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