Chasing star trails with an 8x10

[John Kasaian]

I've got permission to spend as much time as I want between 7:00PM and 7:00AM in a special place, directly South of a landmark I want encircled by star trails. I have an idea where the moon will be rising and setting to avoid getting it in the shot courtesy of
https://www.cambridgeincolour.com/tutorials/moon-night-calculator.htm
Aside from the 1/2 mile hike in and out sugar anting the 8x10, tripod, thermos bottle and lawn chair, I have my choice of HP-5+ or FP-4+ emulsions.
Which film do you recommend?
The lens will be either a 14" Commercial Ektar or 10" Wide Field Ektar
I also have to select an evening that will be cloudless, like under a high pressure system, which should be easy enough to predict this time of the year.
I also have to determine which phase of the moon will offer the best light for my purpose---I'm thinking a full moon might be too bright, washing out the night sky.

It has been a long time since I did any night photography and I can't even recall shooting any star trails using large format.

If the North Star is directly behind my target, the star trails should make complete circles, right?

Is there anything else that needs taking into consideration?

[Gary Beasley]

Personally I would use Acros for its reciprocity characteristics. Faster film will give you fatter trails on the bright stars so you should previsualise with that in mind.

[John Kasaian]

Personally I would use Acros for its reciprocity characteristics. Faster film will give you fatter trails on the bright stars so you should previsualise with that in mind.

I'm tending towards shooting during a New Moon with HP-5+, for 1 hour at f/8. I wasn't aware that Acros is available in 8x10 although I think Tmax 400 may still be?

[LabRat]

The sky is a 24 hour "clock", so for full circles you need to expose for that, but there is that pesky thing called daytime that will blow out the exposure...

But don't fear, after a long enough exposure, other stars will help fill the incomplete circle...

To really get a complete-like effect, you need to expose from after sunset, to before sunrise... Light pollution will start fogging dark areas after not too long time... That can be kept lower by shooting through a dark red filter... Stars themselves are quite bright and will record as they move well...

This is a better project to do if you stay up all night while camping, while one camera is open the entire time... Shorter exposures only record shorter segments of the arcs...

Bring mosquito repellent!!!

Steve K

[Vaughn]

Aperture will affect the width and sharpness of the trails. Aim of those middle ones, f16 or f22 or so, for narrow sharp trails.

Unless you are bringing it or there is lighting on the landmark, it will be siloletted (sp?), so choice of film is not that important...faster film for more contrast between the sky and stars at the same aperture (more exposure of the stars while sky remains black). Reciprocity failure will not affect the exposure of the stars themselves and will help keeping the sky dark. So the exposure you want on the landmark will determine a lot of your exposure needs.

[reddesert]

When the moon is down or new you will have much, much darker skies. If the moon is a thin crescent and you're facing away from it (which you should be, shooting North) then it doesn't brighten the sky very much. IOW, chase both the moon and weather: better to have a thin crescent 1 or 2 days from new moon and clear skies, then perfect new moon but clouds.

At a dark site with long exposures, the difference between nautical twilight (sun 12 degrees below horizon) and astronomical twilight (18 degrees) is noticeable to the film / detector, even if not to your eyes.

Star trails will be centered on the North Star, but the length of the arc depends on your exposure. So if you expose for 1 hour trails will be 1/24 of a circle.

A partial moon low on the horizon (just at moon rise or set) can give a gentle illumination to objects in the foreground, because the light is reduced a lot by the atmosphere and the angle is low - it's basically the moon equivalent of the golden hour. If you were shooting color, the moonlight is actually warm in color temp because the moon's albedo is red (plus reddened by the atmosphere). Color or B&W, sometimes the partially-moonlit landscape combined with star trails is interesting.

So given the effort to get your gear in there and set up the shot, it could be worthwhile taking images spanning moonset (or rise) and several images of different exposure lengths in dark time, at as fast an aperture as you are comfortable with. Don't forget a flashlight, a red light, and a timer/stopwatch/alarm clock.

[John Kasaian]

When the moon is down or new you will have much, much darker skies. If the moon is a thin crescent and you're facing away from it (which you should be, shooting North) then it doesn't brighten the sky very much. IOW, chase both the moon and weather: better to have a thin crescent 1 or 2 days from new moon and clear skies, then perfect new moon but clouds.

At a dark site with long exposures, the difference between nautical twilight (sun 12 degrees below horizon) and astronomical twilight (18 degrees) is noticeable to the film / detector, even if not to your eyes.

Star trails will be centered on the North Star, but the length of the arc depends on your exposure. So if you expose for 1 hour trails will be 1/24 of a circle.

A partial moon low on the horizon (just at moon rise or set) can give a gentle illumination to objects in the foreground, because the light is reduced a lot by the atmosphere and the angle is low - it's basically the moon equivalent of the golden hour. If you were shooting color, the moonlight is actually warm in color temp because the moon's albedo is red (plus reddened by the atmosphere). Color or B&W, sometimes the partially-moonlit landscape combined with star trails is interesting.

So given the effort to get your gear in there and set up the shot, it could be worthwhile taking images spanning moonset (or rise) and several images of different exposure lengths in dark time, at as fast an aperture as you are comfortable with. Don't forget a flashlight, a red light, and a timer/stopwatch/alarm clock.

Good stuff. Thanks!

[John Kasaian]

The sky is a 24 hour "clock", so for full circles you need to expose for that, but there is that pesky thing called daytime that will blow out the exposure...

But don't fear, after a long enough exposure, other stars will help fill the incomplete circle...

To really get a complete-like effect, you need to expose from after sunset, to before sunrise... Light pollution will start fogging dark areas after not too long time... That can be kept lower by shooting through a dark red filter... Stars themselves are quite bright and will record as they move well...

This is a better project to do if you stay up all night while camping, while one camera is open the entire time... Shorter exposures only record shorter segments of the arcs...

Bring mosquito repellent!!!

Steve K

Definitely mosquito repellent. Thanks!

[John Kasaian]

Aperture will affect the width and sharpness of the trails. Aim of those middle ones, f16 or f22 or so, for narrow sharp trails.

Unless you are bringing it or there is lighting on the landmark, it will be siloletted (sp?), so choice of film is not that important...faster film for more contrast between the sky and stars at the same aperture (more exposure of the stars while sky remains black). Reciprocity failure will not affect the exposure of the stars themselves and will help keeping the sky dark. So the exposure you want on the landmark will determine a lot of your exposure needs.

Lighting will be an issue. There's no power to the site and it's in a pretty dense forest, so I'll be stuck with a silhouette I'm guessing. Thanks!

[Drew Wiley]

John, ACROS 8X10 would be very difficult to find, because the tiny bit remaining is probably being jealously hoarded. I used up my last sheet of it a couple years ago. TMax400 is going to be no.2 choice in terms of long-exp characteristics, and will be way sharper than HP5. FP4 sounds awfully slow. Test any of these in 35mm first. Someday I'll have to show you the secret UFO landing site up above Granite Creek. It was about 5 mi back in the woods, and once a summer a UFO cult would gather there and wait in a circle holding hands and chanting. Finally it happened. Of course nowadays if some frisbee with flashing perimeter lights went over someone's back yard BBQ at night they'd just snicker about what the neighbood kids were up to. But in the mid-60's, way back miles from even the nearest dirt road, who would have imagined some kids would design a very elaborate model and giant slingshot device, and haul in six car batteries for sake of powerful projector black light strobe system, just to make fools out of what were already fools? But that 12-second UFO overflight was good for a lifetime of laughs afterwards, and it sure made true believers out of them.

[Corran]

Get there early and focus roughly while it's light out. Use some tilt to get the foreground and stars in focus once you can see some, which may sound obvious but is harder said than done depending on the geometry of the object...especially as I'd suggest shooting at the widest aperture possible or close to it.

I once shot some Provia at f/11 for like 6 hours and got literally nothing on the film. I was using a 2x center filter though which was dumb. So I think at f/16 you'd be already pushing it, so I'd shoot for f/8 or wider.

HP5 would be a big no-no I think. T-Max 100 or 400, or Delta 100 for sure would result in more actual exposure.

[John Kasaian]

John, ACROS 8X10 would be very difficult to find, because the tiny bit remaining is probably being jealously hoarded. I used up my last sheet of it a couple years ago. TMax400 is going to be no.2 choice in terms of long-exp characteristics, and will be way sharper than HP5. FP4 sounds awfully slow. Test any of these in 35mm first. Someday I'll have to show you the secret UFO landing site up above Granite Creek. It was about 5 mi back in the woods, and once a summer a UFO cult would gather there and wait in a circle holding hands and chanting. Finally it happened. Of course nowadays if some frisbee with flashing perimeter lights went over someone's back yard BBQ at night they'd just snicker about what the neighbood kids were up to. But in the mid-60's, way back miles from even the nearest dirt road, who would have imagined some kids would design a very elaborate model and giant slingshot device, and haul in six car batteries for sake of powerful projector black light strobe system, just to make fools out of what were already fools? But that 12-second UFO overflight was good for a lifetime of laughs afterwards, and it sure made true believers out of them.

Dang, I miss all the fun!

[Vaughn]

Lighting will be an issue. There's no power to the site and it's in a pretty dense forest, so I'll be stuck with a silhouette I'm guessing. Thanks!

Pop a handheld flash a few times.:cool: The exposure does not have to be too long to get the feel of a circle. There should be plenty of examples on-line with the length of the exposure noted to give you an idea of length of star trails over time. And unless you need (and can get) detail in the landform, reciprosity failure can be your friend and a conventional film will help to keep the sky black as the stars will not be dimmed by reciprosity failure.

I have 2 boxes of 8x10 Acros you can't have. Bought them in Kyoto a couple years back.

[John Kasaian]

Pop a handheld flash a few times.:cool: The exposure does not have to be too long to get the feel of a circle. There should be plenty of examples on-line with the length of the exposure noted to give you an idea of length of star trails over time. And unless you need (and can get) detail in the landform, reciprosity failure can be your friend and a conventional film will help to keep the sky black as the stars will not be dimmed by reciprosity failure.

I have 2 boxes of 8x10 Acros you can't have. Bought them in Kyoto a couple years back.

Ilford is what I have, so I'll roll with that

[LabRat]

Lighting will be an issue. There's no power to the site and it's in a pretty dense forest, so I'll be stuck with a silhouette I'm guessing. Thanks!

If you need some lighting, consider some large flashbulbs... Compact, require some low voltage batteries to power, and even if not enough power to cover scene, at least will start reaction on film to allow ambient light to help build image during long exposure...

Steve K

[Gary Beasley]

Lighting will be an issue. There's no power to the site and it's in a pretty dense forest, so I'll be stuck with a silhouette I'm guessing. Thanks!

This is where you explore the option of painting with light. If you have some good handheld high power lights you can find a vantage point that you can use to illuminate interesting parts of the landscape without blowing up the foreground with light. As always a good idea to experiment on a less important shoot to get a feel for how it will work.

[Fred L]

definitely go with a new moon. also, depending on ground conditions, and how long you think your exposure will be, I'd be looking at dew control as well. if yer not keen to hump a battery pack and heater straps, some chemical hand warmers will work as well. wrap an elastic band around them around the rim of the front element and you shld be fine. not sure how dry it is where you're going but where I am, dew is an issue with long exposures.

fwiw, I used 320 TXP 8x10 when I did trails and exposures I think were couple of hours, give or take. 300 5.6 lens (or might have been Fuji 210 5.6

good luck and have fun, and hope you post the result !

[Mark Sampson]

Wow, lots of good info here. I've tried LF star trails casually a few times, with occasional success. I remember trying to shoot color star trails in the '80s with Vericolor film and an f/8 lens... basically no-go. But I'll try again when I next get a chance... good luck John!

[Scott Davis]

A Vivitar 283 with a fresh set of batteries would probably be sufficient to light paint your subject, should you be able to get close enough to it, and it's not too big. Remember to keep yourself between the flash and the lens so you don't get a flare spot from the flash head in the image.

[Fred L]

this photo was taken a few years ago, and I wish I had a wider lens to include more foreground, and definitely more sky. can't recall why Polaris isn't more distinct. the neg looked slightly thin but scanned fine.

[Gary Beasley]

Polaris is not super bright and not precisely on axis with the earths rotation. Thats probably why its not as distinct as you expected

[Fred L]

so if I had a suuuuper long exposure, Polaris might have described a...doughnut ? lol thanks for the info, couldn't figure it out. stay safe

[Vaughn]

A very bright doughnut -- the star may not be that bright, but it is in about the same spot the whole time...as seen in the posted example.

[John Kasaian]

I think my biggest challenge is going to be finding a smoke free night sky this next new moon :rolleyes:

[Drew Wiley]

A smoke-free view FROM the moon you say. Yes, that makes sense.

[John Kasaian]

A smoke-free view FROM the moon you say. Yes, that makes sense.

Smoke free so the stars will be visible:confused:

[Drew Wiley]

I was only pointing out the fact that the surface of the moon is the only smoke-free vantage point to set up a camera right now. As for viewing conditions from Mars, I'm there right now. It's cold, still barely twilight, and the entire sky dark orange. But perhaps the real Mars has more breathable air at the moment. The remains of Jose Basin have now reached my own lungs, but the air is nowhere near as unhealthy as two years ago when north Bay burbs full of plastic, oil, and aluminum were incinerating.

[Roger Thoms]

Yeah, it’s night at my house out here in the Sunset district of San Francisco, with the added bonus of an orange sky. I’ve lived in the SF Bay Area for 36 years and have never seen anything like it.

Roger

[Tin Can]

Sorry to hear about all the fire

I just posted my good times 1980 Polaroids from the forest


Yeah, it’s night at my house out here in the Sunset district of San Francisco, with the added bonus of an orange sky. I’ve lived in the SF Bay Area for 36 years and have never seen anything like it.

Roger

[Roger Thoms]

Thanks Randy. Where did you post your Polaroids, they sound like fun.

Roger