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07-21-2018, 11:20 PM   #1
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Full Lunar Eclipse and the 645Z

Greetings from Namibia.

I'm lucky enough to be in one of the best spots for the upcoming eclipse.

I do not have a tracking head.

I've got about everything else.

My longest modern lens is the SMC FA 645 120mm F4

My Longest lens is a SMC Takumar 6 x 7 400mm F4

My goal is to shoot a series with a well known landmark, either the Brandberg which has a better orientation for familiarity or the Spitzkope, not ideally oriented but very familiar.

Like this series shot by Nasim Mansurov

Does anyone have a feeling about time spacing to get black sky in between the 'moons' I'm trying to avoid overlap.

I've got a decent handle on the exposure lengths.

Any thoughts, insights or suggestions will be most welcome!

Many thanks

Chris

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07-22-2018, 12:48 AM - 1 Like   #2
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This is only a rough approximation to give you something to think about. Persons experienced in doing this may provide a more accurate answer.

The moon (like the sun) subtends about a half-degree in the sky. It moves about the earth roughly 360 degrees per day. (There are some corrections that can be made to refine this by about 3% due to the moon lapping the earth once a month, and also the angular diameter is not exactly a half degree, but its too late here to bother looking them up.) So, the moon moves its angular diameter in roughly 1/720 of a day, or every 2 minutes.Thus , if you choose a fraction "f" of the lunar angular diameter to be black, then multiply 2 minutes by 1 + f, you will get the desired time between the start of each shutter opening.
07-22-2018, 03:58 AM   #3
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Amazing work, thanks for sharing, Don't have any suggestions
07-22-2018, 06:39 AM   #4
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That's a great opportunity! A few suggestions from someone with almost no experience with composite photos:
- Maybe bold in your post that it's not your photo, but something you want to achieve
- Since exposure time will be brief, you will be able to take many more shots than required for the final photo. If you want to avoid star trails, like in the photo you linked, it'll take some pp work to cut out just the moon, so there's less of a need to get spacing just right and only those photos.
- Experiment before the eclipse, the moon is moving at the same speed

07-22-2018, 10:08 AM   #5
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QuoteOriginally posted by Namibchris Quote
My longest modern lens is the SMC FA 645 120mm F4

My Longest lens is a SMC Takumar 6 x 7 400mm F4
If you want the full eclipse panorama, per your sample image, you need wider lenses than either of these! The overall eclipse will last something like 4 hours! The total phase alone is about 1 3/4 hours long. As noted by kaseki above (his other numbers are right on, too - like the lunar diameter), the apparent motion of the moon is about 15 degrees per hour due to the earth's rotation. Thus, during the complete eclipse cycle, the moon will move around 60 degrees across the sky. If you want some extra field of view on either end of the complete cycle, you need a lens that gives you at least a 70-80 degree FoV along the eclipse path.

If you need sky details, like where in the sky will the moon be at mid-eclipse - so you can pre-position your camera, check out the stellarium program: Stellarium Astronomy Software


QuoteOriginally posted by aaacb Quote
- Experiment before the eclipse, the moon is moving at the same speed
And, don't forget to do some pre-eclipse practice.
07-22-2018, 10:32 AM   #6
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QuoteOriginally posted by Namibchris Quote
Does anyone have a feeling about time spacing to get black sky in between the 'moons' I'm trying to avoid overlap.
Thinking out loud here...

@kaseki correctly said 2+ minutes between photos. The math is good. I'm wondering about the logistics:
  • Do you have an automatic timer solution that can be set in precise increments? Intervalometers often jump from 2 minutes to 3 minutes; you can't program an exact 2 minutes 8 seconds for example. Maybe the 645Z can do it.
  • If something goes wrong with any one photo, you'll have a huge gap.
Consider a much shorter interval, then select which ones to use as layers later. With a 20 second interval the moon will move approximately 15% of its diameter in each photo. If there are some bad photos - let's say you bump the tripod and need a minute to fix it - you'll be able to shift the position of some frames during processing.

A lunar eclipse can last around 3 hours. That means you'll end up with 540 photos.

Do you plan to bracket the entire series, or are you going to adjust camera settings during the eclipse?
  • Bracketing would fill memory with over 1500 photos and deplete battery. Schedule one or more battery changes.
  • Adjusting settings in the middle is prone to human error but may avoid the battery change.
07-22-2018, 06:36 PM   #7
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Shots like these are usually composites involving shots at different focal lengths: 1) short exposure long-telephoto shots for the moon, 2) longer wide-angle exposure for the stars (possibly tracked), and a longer untracked wide-angle exposure for the landscape.

The moon is blindingly bright relative to the stars and night landscape. The "Lunny f/11" rule for full moons implies an exposure time of 1/ISO at f/11.

The moon is also really tiny relative to the stars and night landscape (and high above the horizon). Getting shots of the moon and landscape requires a wide-angle lens but then the moon is tiny.

The night landscape also needs a long exposure probably taken at a very different time. If you shoot the landscape with the non-eclipsed full moon hanging over it, the result is like taking a day-time landscape with the sun in the frame: you get both flare problems and unfavorable backlighting of the landscape.


There's tons of additional information at How to Photograph a Lunar Eclipse

07-22-2018, 08:25 PM   #8
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My experience shooting an eclipse was 1)work on the night scene without the moon and use that as the background 2)use a long lens for the moon photos and adjust exposure as needed, it gets very dim at full eclipse. Take plenty of pictures and arrange them later. I manually set daylight white balance and used raw+.
07-23-2018, 06:40 AM   #9
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QuoteOriginally posted by kaseki Quote
This is only a rough approximation to give you something to think about. Persons experienced in doing this may provide a more accurate answer.

The moon (like the sun) subtends about a half-degree in the sky. It moves about the earth roughly 360 degrees per day. (There are some corrections that can be made to refine this by about 3% due to the moon lapping the earth once a month, and also the angular diameter is not exactly a half degree, but its too late here to bother looking them up.) So, the moon moves its angular diameter in roughly 1/720 of a day, or every 2 minutes.Thus , if you choose a fraction "f" of the lunar angular diameter to be black, then multiply 2 minutes by 1 + f, you will get the desired time between the start of each shutter opening.
Thanks for making my head hurt!

That helped a lot really!

---------- Post added 07-23-18 at 06:42 AM ----------

QuoteOriginally posted by Lake Quote
My experience shooting an eclipse was 1)work on the night scene without the moon and use that as the background 2)use a long lens for the moon photos and adjust exposure as needed, it gets very dim at full eclipse. Take plenty of pictures and arrange them later. I manually set daylight white balance and used raw+.
Thank you, does this mean you are shooting the landscape and layering on the moon? or shooting the landscape as an exposure and the moon as an exposure every shot?
07-23-2018, 09:02 AM   #10
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I admit that when I first looked at Mansurov's image, I assumed that it was the result of a series of superimposed shots. However, that would likely lead to complex shadows in the foreground. I also considered that maybe the near dawn image of the background would provide the additional landscape brightness as the last superimposed image. However, I just recently finished reading Glenn Randall's The Art, Science, and Craft of Great Landscape Photography, which treats astronomy shots with visible landscape as Photoshop projects. Accounting for Randall's approach, I now realize that without further information Mansurov's image might well be a combination of separate images, each of which was taken with its own best exposure. Thanks to all of you above who pointed this out in your own way.

There is also the question of how small a half-degree moon will look in a lens intended for a quasi panoramic landscape view. Are Mansurov's moons the right size for the background extent?

Last edited by kaseki; 07-23-2018 at 09:10 AM.
07-23-2018, 10:37 AM   #11
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QuoteOriginally posted by kaseki Quote
I admit that when I first looked at Mansurov's image, I assumed that it was the result of a series of superimposed shots. However, that would likely lead to complex shadows in the foreground. I also considered that maybe the near dawn image of the background would provide the additional landscape brightness as the last superimposed image. However, I just recently finished reading Glenn Randall's The Art, Science, and Craft of Great Landscape Photography, which treats astronomy shots with visible landscape as Photoshop projects. Accounting for Randall's approach, I now realize that without further information Mansurov's image might well be a combination of separate images, each of which was taken with its own best exposure. Thanks to all of you above who pointed this out in your own way.

There is also the question of how small a half-degree moon will look in a lens intended for a quasi panoramic landscape view. Are Mansurov's moons the right size for the background extent?
Mansurov's moon's are far too large given the very long arc of the moon's path during the eclipse itself. Also, the shadows are wrong on the landscape.

As Randall's book points out, these types of images are photoshop projects requiring the artful placement of cut-and-paste moon images on a cut-and-paste landscape and cut-and-paste starfield.

Last edited by photoptimist; 07-24-2018 at 05:28 AM. Reason: typos
07-23-2018, 08:14 PM   #12
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QuoteOriginally posted by Namibchris Quote
Thanks for making my head hurt!

That helped a lot really!

---------- Post added 07-23-18 at 06:42 AM ----------


Thank you, does this mean you are shooting the landscape and layering on the moon? or shooting the landscape as an exposure and the moon as an exposure every shot?
I took one exposure of the scene. I took many separate exposures of the moon adjusting the camera settings as needed. I needed a long lens to get a large enough moon to place on the background. The moon was much too small with a lens wide enough to capture a foreground. Practice moon shots now with your 400mm lens so you are setup before the eclipse starts. Each moon picture I took was a separate exposure without the background, I had to frequently adjust the camera position as the moon travels very fast.
07-25-2018, 08:00 AM   #13
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I'd try for a real photograph of the eclipse in some way. I did a single frame image of the 2017 solar eclipse with a normal focal length that put it in context with something on the ground. And while totality was small in the frame, it was still recognizable. The image you posted I see it as a computer graphics art project in lieu of a photograph. But, yeah, practice before the event if you can and best wishes on the outcome.
07-25-2018, 11:41 PM   #14
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final thoughts

I agree that the image I originally posted is pretty well over the top. I am going for a composite but accurate in scale. I am going out late this afternoon to recon the spot for tomorrow, I am leaning towards shooting the eclipse over the Erongo Mountains rather then the Spitzkope, much better orientation and less commonly photographed then either the Spitzkope or the Brandberg. In addition to tonight's location scouting I am also going to get the test exposures dialed in and decide if It is better to use the Takumar 400 with the 2x converter or without. Camera is rock solid and I'll attach weights to the tripod, mirror up of course and cable release. Thanks for all the suggestions. fingers crossed i don't screw the pooch on this.
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07-26-2018, 12:36 AM   #15
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Hi Chris,

In the Netherlands we will also have a eclipse or bloodmoon. It starts just after moon rise so it might still be very light. I also will have to go somewhere where i can see the horizon as the moon obviously will be very low. I am curious what i will get.
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