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jesse1996
2-Apr-2017, 15:48
Hello All! with the anticipated solar eclipse coming up 21 August this year. Does anyone have any experience with shooting this event with 4x5 or 8x10 film? It seems like there a lot of aspects about it that I'm having a hard time pulling up information on. Any help is really appreciated!

Thalmees
2-Apr-2017, 16:01
Hello All! with the anticipated solar eclipse coming up 21 August this year. Does anyone have any experience with shooting this event with 4x5 or 8x10 film? It seems like there a lot of aspects about it that I'm having a hard time pulling up information on. Any help is really appreciated!
Hello jesse,
Protect your eyes.
Good luck.

Ted R
2-Apr-2017, 16:54
Kodak produced a helpful booklet with the title ASTROPHOTOGRAPHY BASICS AC-48 and there are about eight pages devoted to solar eclipse photography, it is long out of print, see if you can locate a used copy.

One aspect that deserves some consideration is the choice of lens. The sun is a small object, about half a degree across, which means that the use of a normal length lens will produce a very small image. When a larger image is wanted, perhaps one quarter to one third of the size of the frame, then the lens focal length required may be more than ten times normal, perhaps 1m - 2m for 4x5 and double that for 8x10. This is a very large lens and requires special mounting arrangements. Much astrophotography is done using telescopes of long focal length where the camera is attached to the telescope.

jesse1996
2-Apr-2017, 18:56
you think its possible to gerrymander a telescope made from PVC pipe or something like that with the lens attached at the other end?

Leigh
2-Apr-2017, 18:58
With only two exceptions, my wife has watched every eclipse that's happened anywhere over the last 50 years.
She shot most of them, using 35mm, not LF, with focal lengths out to about 250mm.

The size of the sun's image on the film depends exclusively on the lens focal length, not the film format.

Fred Espenak published a table of sun image size v. lens focal length. Excerpts:
105mm = 1.0mm
200mm = 1.8mm
500mm = 4.6mm (~0.2 inches)

But you're going to have other problems, such as keeping the sun centered in the frame as it moves.
All work except totality MUST be done with a solar filter over the lens. It's extremely dense.

Also, you need to have the camera on an equatorial mount, not our common az-el mount.
An equatorial mount has the rotational plane parallel to the earth's equator.
That's because the sun traverses the plane of the ecliptic from our viewpoint, and in fact defines same.

- Leigh

tgtaylor
2-Apr-2017, 20:32
Difficult to do but you could capture the various stages of the eclipse on one sheet of film (I'd use 8x10).

Thomas

Jim Jones
3-Apr-2017, 06:47
you think its possible to gerrymander a telescope made from PVC pipe or something like that with the lens attached at the other end?

Yes. The biggest problem may be in finding a quality lens of adequate focal length. Lacking that, you can always take pinhole images of the eclipse. This also eliminates the necessity of using a solar filter for most exposures. Long ago I tried to photograph a solar eclipse with a 32-foot-long pinhole camera made out of black plastic tubing. It was too cumbersome, but worked well enough when shortened to 24 feet. The front of the camera was suspended from a telephone pole, and the film end held by hand and moved until it was centered on the shadow of the front end. Another way of operating such a long camera is to rest the rear on the ground and manipulate the tube to center its shadow on the film end. With a little more work, a finder could be improvised. A string operated an old Prontor shutter. As I recall, the pinhole was about .070" in diameter, and yielded a quite fuzzy image. Better than a pinhole may be a .25 diopter close-up filter. Don't wait until the last month before improvising and testing such a camera. Plastic tubes flex: even the 24 foot tube required bracing.

Jim Jones
3-Apr-2017, 07:32
. . . But you're going to have other problems, such as keeping the sun centered in the frame as it moves.
All work except totality MUST be done with a solar filter over the lens. It's extremely dense.

Also, you need to have the camera on an equatorial mount, not our common az-el mount.
An equatorial mount has the rotational plane parallel to the earth's equator.
That's because the sun traverses the plane of the ecliptic from our viewpoint, and in fact defines same.

- Leigh

Except for totality, a solar filter is needed somewhere in the optical path, but not necessarily in front of the lens. A sheet of film completely exposed and developed and double loaded in front of the raw film in the holder makes an expensive solar filter. Experiment long before the day of the eclipse.

An equatorial mount may be necessary only during those few minutes of totality. Otherwise, the fast shutter speeds usually necessary for photographing the Sun should stop its apparent movement.

Thomas Taylor's suggestion of capturing the entire event on one sheet of film is practical, although time consuming and perhaps difficult. I captured part of a lunar eclipse at intervals of 2 minutes on a Speed Graphic. This bunched the individual moon images awfully close, but it worked since part of the moon was unlit. 4 or 5 minutes might be better for the Solar eclipse. The entire Solar eclipse event lasts over two hours. Getting all of it on one piece of film without any glitches involves much luck or very good preparation. An intervalometer would help.

Leigh
3-Apr-2017, 08:53
Except for totality, a solar filter is needed somewhere in the optical path, but not necessarily in front of the lens.
A solar filter is required between the sun and the film AND between the sun and your eyes.
That's true even if you are viewing the sun's image on a ground glass.
Depending on the camera configuration, this may be most easily done with a filter over the lens.


An equatorial mount may be necessary only during those few minutes of totality. Otherwise, the fast shutter speeds usually necessary for photographing the Sun should stop its apparent movement.
The equatorial mount makes it easier to pan the camera while tracking the sun.

-Leigh

ben_hutcherson
3-Apr-2017, 09:57
I'll be reading with interesting-I may take the day off work and head down to "ground zero" in Hopkinsville.

Vaughn
3-Apr-2017, 10:56
There are many way to "capture the event". It helps to decide what on aspect of the event one wishes to use to describe the entirety. That will then determine how one approaches the subject/event. Multiple exposures, one long exposure, with or without the sun in the image, and so forth.

Decide what you want the image to look like, then work on the way to achieve that image. Of course, technical challenges may alter your original vision and there may have to be feed-back between the creative and technical aspects to decide on what the final image will look like.

I photographed a lunar eclispe -- one exposure every 10 minutes (8x10, 300mm -- perfect to get the whole show on one piece of film). Two or three hours or so from full moon to full moon. Everything worked perfectly except I did not increase the exposure as the portion of the moon lit up decreased. By keeping the same exposure, I underexposed the moon badly during half of the eclipse...did not show up on the film. But it was a wonderful experience. Just goes to show that some planning and research is not a bad thing!

The last partial solar eclispe we had, I photographed the side of my house (Rolleiflex) -- the plum tree's shadow was thrown there and the shadow was a bunch of partial solar eclipses. Pretty neat.

jesse1996
4-Apr-2017, 23:20
My goodness, i definately plan on experimenting before hand with solar photography. Seeing what exposures and filters work best, In a perfect world I'd have a lens that could have the sun fill half the frame with the corona in perfect detail, but even that is hard for pro digital cameras to pulll off. If I'm scanning film it will come to a decent amount of detail anyways if I can find the right set up before then

LabRat
5-Apr-2017, 03:24
A solar filter is required between the sun and the film AND between the sun and your eyes.
That's true even if you are viewing the sun's image on a ground glass.
Depending on the camera configuration, this may be most easily done with a filter over the lens.




-Leigh

A solar filter is ALWAYS used in front of a lens, as this prevents the optics from focusing the sun spot onto a glass or film filter inside, that could break or burn while watching... (And it cuts excess brightness flare from the viewing/taking system...)

Finding a cheap C/L telescope that a solar filter can be added safely on front will do... A welding goggle lens that can be safely placed in front of a camera lens can work with the taking end...

Be aware that during bright sunshine, there is a great amount of air turbulence due to ground heating convection currents, so even with an advanced rig, it looks like viewing through boiling water, made much worse by higher magnifications... (Most solar work is done early in the morning, or in very cold weather...)

Steve K

MrFujicaman
6-Apr-2017, 16:17
B & H just emailed me about having solar filters-they are anywhere from $69 to $239 bucks

Jac@stafford.net
6-Apr-2017, 16:54
In my lifetime I think I have seen all the eclipse photos that can be made. (Someone surprise me, maybe the space station transiting the event!)

I probably will not succeed but what I wish to make is a picture of a mass of people trying to capture the eclipse, with or without a camera.

Shame. I have a Hasselblad 500 with a 750mm lens which thanks to to our wonderful digital progress is inadequate. :)

-- Olde Jac

Fr. Mark
6-Apr-2017, 21:48
I want to encourage those of you in the path of the eclipse to consider the photos of shadows cast. As noted above they are totally different from normal based on a partial I saw in 1994, in Indiana. By all means get the ones of the sun but consider some point and shoots of the environment around you as it approaches totality. Even sound recordings might be interesting: the birds and insects all went to twilight mode, too. And it got quite cool out for the time of year. Sounds like fun, wish y'all the best.

devb
7-Apr-2017, 07:18
Don't forget that there's another eclipse in the continental US on April 8, 2024, if you happen to screw anything up.

jesse1996
8-Apr-2017, 13:14
At least there are other chances!