The blue light beam in the upper left of the center of the screen is Comet Neowise August 1st.
This time, I will take up the fact that I was able to observe Comet Neowise, which is moving away from the Sun and the Earth, from Nairobi.
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Comet Neowise, a comet that passes the perihelion on July 3 and gradually moves away from the Sun.
It is orbiting a huge elliptical orbit, and the next appearance is the future more than 6000 years ahead.
Over 3000 years since the end of the solar system, it has been gradually accelerated by the gravity of the sun.
It is said that it will reach the maximum speed when it passes the perihelion on July 3, and will move away from the sun and return again over 3000 years with this momentum.
Even so, there are various comets.
It is thought that comets scattered meteor elements and stardust in the night sky in orbit, and also brought amino acids, which were the source of life, to the earth.
It may be like a capsule of life, or a celestial body that was the key to the origin of life on Earth.
The comet was discovered by an American satellite in March this year.
Since the name of this artificial satellite (infrared astronomical satellite) is "Neowise", it is called Comet Neowise, but the official name is C / 2020 F3.
The official name isn't something that makes you feel attached.
In the future, the number of discoveries of new comets by artificial satellites will increase.
Comet Hyakutake appeared in 1996, shortly before the caretaker came to Africa.
I remember seeing a comet with a long tail and seeing it with the naked eye.
The pale blue color emitted by the comet was very beautiful, and I still have that impression.
I myself haven't observed comets since then.
I also compared the image with the D800E, the first photo of the night sky taken with the D850.
Can you see the comet in August?
During July, Nairobi was barely sunny, and the caretaker himself could not observe Comet Neowise.
Well, if I knew it earlier, I might have been able to observe it.
Near the end of July, the sunny days began to peek, albeit rarely.
I don't know the location of the comet, so I'll simulate it first.
I put the orbital data of Comet Neowise obtained from Wikipedia into the astronomical simulation and software, Stella Navigator 95, and simulated it.
It is a software 25 years ago that was also active in solar eclipse time-lapse photography.
There are some annoying things such as having to turn off the Internet and start up in Windows XP mode, but I have never felt a shortage in orbit calculation.
I don't really need beautiful graphics, and I'm trying to figure out how much I can use.
The design of the Windows 95 era is fresh and cool to look at now.
In addition to XP mode, compatibility mode Windows 95 is used to operate this software.
There are no extra functions that put a burden on the PC, and various settings can be made on one screen.
By the way, I remember that Word and Excel in the Windows 95 era were moving very quickly.
CPU at that time, Pentium 1, clock frequency about 150MHz single core. An era when the memory was as large as 128MB. That was enough.
Even though it's just a document, these days even high-spec machines work more slowly than they did back then.
I feel that many of the software designs at that time were purely pursuing ease of use, unlike now.
Compared to that, recent apps have a strong tendency to cheat with graphics even though the content is not big.
When the purity of the past disappears and I get angry, I feel like I can communicate with people.
I put in the necessary orbital data
I put the orbital data published on the Internet into the simulator.
Set appropriately except for orbit data.
By entering this number, you can see in detail when and where the comet looks.
Furthermore, the direction in which the tail flutters can be simulated separately for ions and dust.
Now I have a good idea of the orbit of Comet Neowise as it approaches and moves away from the Sun in the solar system and its general view from Earth.
I moved from Ursa Major and am now in Coma Berenices.
Well, can you capture it with a camera?
Seen from Nairobi, Coma Berenices is about 40 degrees above the west sky and horizon by the time the sun goes down.
It's just below the first-class star Arcturus in Boötes.
Observation method
Currently, in Kenya, the observation site this time, going out after 21:00 is prohibited due to the influence of the coronavirus.
Therefore, it is not possible to go out to the dark, light-polluted suburbs of the night sky.
So, I have no choice but to observe from my house, but it is impossible to observe from the roof of the apartment because the west sky is not open.
I wondered if I could observe it from a small window in the room, and when I adjusted the direction and the angle of height with a compass in the direction in which the comet could be seen, I was lucky to open that direction.
However, there is a tree in that direction that seems to get in the way, and it seems that it will be hidden behind this tree long before it disappears behind a distant building, but it seems that it can be observed somehow.
When I found out that it could be observed, I installed a Kenko Tokina Sky Memo T near the window of the room.
The shooting was done like this, of course, turn off the lights
This Sky Memo T and all operations are operated wirelessly with a smartphone.
The polar axis was roughly aligned with a compass, and the angle was aligned with a smartphone app.
Reinforcing bars of the building are quite magnetic and the exact north cannot be derived.
Here in Nairobi, about 1 degree south latitude, even if you go outside with a good view, you can not see the North Star, and you can not see the four stars in Octans.
It is very difficult to align the polar axis of the equatorial mount in the area near the equator.
I will write about that soon.
I am very impressed that I sometimes return to Japan and can install the equatorial mount very easily and with super precision thanks to the North Star.
The lenses used for shooting comets were 85mmf1.8, 180mmf2.8, and 300mmf4 in that order.
Even though it is better than Tokyo, this is Nairobi, the capital of Kenya, and the light pollution is severe.
Recently, the number of street lights has increased and the sky is dull.
The condition of whether or not you can finally see 3rd and 4th magnitude stars even if you look at the night sky or stare at it.
At first glance, you can only see up to 2nd magnitude stars.
The Milky Way could be seen in the sky of Nairobi 20 years ago, but the conditions for seeing the stars have become very bad these days.
Under these conditions, it seems impossible to find a comet that is getting very dark with the naked eye.
Even if you can't see it with the naked eye, if you take a picture, you should be able to see a fairly dark star even under these conditions.
So, first of all, to search for a comet, I attached an 85mm f1.8 lens to the D850 and started shooting.
By taking a few shots with a wide angle of view of 85 mm and searching in only the general directions, I could see a comet with a blue glow, which is clearly different from other stars.
Below the photo is the first comet captured by the 85mm lens.
And the tree below this is the obstructive tree I mentioned earlier.
It seems that there is not much time left for observation.
I found a comet
It is already the time to see this comet, but the beautiful blue light of the comet was recognized even with the 85mm lens, although the tail was not visible.
The sky is also getting darker.
If I had to shoot everything before the comet was hidden behind a tree, I immediately switched to 180mm and focused on the comet.
I took the above picture with D850, but the noise is severe when I make it the same size despite ISO400.
"Hate !?", are you not good at the D850 starry sky? Is it? ?? ??
So, at first, I was planning to shoot with the D850, but I decided to shoot with the D800E, which surely captures the image.
Shooting with the camera and lens replaced in a hurry until the comet hides in a tree.
It's not a comparison because the twilight isn't over yet, but a comparison between the D800E and D850
I shot it before it was hidden in a tree and before it was dark.
The D800E has less noise and the shadow tone is better expressed.
The difference in shooting time of 12 minutes during this time period cannot be said because the twilight also changes significantly.
Here, the state of the shutter shock of the camera was captured, so about that.
A satellite probably crossed near the comet while shooting with the D800E.
That is the trajectory on the left of the photo.
It could be a meteor shower in the Perseids meteor shower.
I'm not sure because I haven't seen it with the naked eye.
From the state of the trajectory, I think it is probably an artificial satellite.
The time when the sun is just setting, the time when the artificial satellite looks brightest. I'm sure that the reflection of the satellite panel will reflect the sun's rays toward us.
It gave off a bright light and crossed the screen down or up for 10 seconds of exposure.
The trajectory of the D800E's shutter shock was clearly captured, so that part was enlarged.
It takes about 1 second for the vibration to decay.
I'm not sure 100%, but the mirror lockup function should have been included at this time.
If the tripod or pedestal is strong, the state of this damping will be smaller and will converge faster.
Silent shooting using the live view of the D850, not to mention the mirror, the mechanical shutter is not activated, so you can shoot without generating any vibration.
This is a very nice feature for astrophotography like this.
This time, the D850 is shooting using that function.
D850, D800E confrontation with 300mm lens
Then, when the twilight was over and the sky was completely dark, I shot at 300mm.
It's time to find out if the D800E and D850 are suitable for starry sky photography!
The output photo is a D800E with the same pixel size and cropped to 900x600, and the D850 image is slightly reduced to fit the same area as the D800E.
And in both photos, I adjusted the tone with a tone curve so that the look would be almost the same.
Please be forewarned that the tracking has not been decided because it is charming.
D800E pixel 1x
Image taken with the D800E released in 2012.
You can see how the light beam spreads quite widely.
There are also subtle shades from the core.
The D850 has been adjusted to the same size as the photo above, and the tracking has been decided! ??
The spread of the light beam is smaller than that of the D800E.
The core of the comet also looks sleepy, and the sharpness seems to be fading.
The color information of the D850 also looks weaker than that of the D800E.
The photo of the D850 below is tracked well, while the D800E is not tracked well and is blurry.
The image taken with the upper D800E, which should be unsatisfactory due to blurring of the image, is richer in the appearance of the comet's nucleus, the light beam spreading from it, and its shading than the one taken with the lower D850. There is.
The spread of the light beam itself is lighter and wider on the D800E.
That? The D800E seems to have better tone and resolution.
D850 lost to D800E
A comparative test by shooting this comet, it seems that the D800E will be better off.
With the shooting conditions and camera settings this time, the D800E with 36 million pixels is less noisy and subtle than the D850 with 45 million pixels in order to faithfully reproduce pale shades such as celestial bodies, comets and nebulae. It turned out that even a nice tone can be reproduced.
I can't say the final conclusion because I can change the settings in various ways.
In this shoot, I felt that the difference in the image was higher on the D800E.
The performance of the sensor itself is very important for producing such a light concentration, and it is neither cheated by the engine nor cheated so well.
I don't know if the cause is the increased number of pixels, the characteristics of the sensor manufacturer, or the engine.
I will change the settings in various ways to find the setting that best captures the starry sky.
After trying it all, the final conclusion will be.
When the 12-megapixel D3 was changed to the 36-megapixel D800E, despite the fact that the number of pixels had tripled, high-sensitivity characteristics and subtle shades of shadows such as celestial bodies began to appear. I was really surprised at that.
With only 2 minutes of exposure, the D800E produces this much tone without compositing.
As you can see from the picture above, the D800E's terrifying shadow depiction ability.
This depiction is done with a high pixel count of 36 million pixels.
No long-time noise reduction is used.
It has a mechanism that cancels the low-pass filter, and its resolution is completely different from that of a camera that uses a low-pass filter.
I thought that the total amount of information in one real photo would be 5 to 8 times that of D3.
I heard that the D850 adopted a mechanism to efficiently receive light by backside illumination of the seamos sensor, and I expected that the image of the shadow part would be greatly improved compared to the D800.
It feels disappointing.
On the contrary, it seems that the tone of the shadow part has faded due to the increase in noise due to the increase in the number of pixels.
Due to the increased noise, I felt that the amount of information in the entire photo was reduced even though the number of pixels was increased.
36 million pixels and 45 million pixels, the difference is only 12% in length ratio.
It seems unlikely that the benefits of increasing the number of pixels will be obtained so much.
It's still my first time shooting the starry sky, so I'll try to find out what it really is.
This time, I took a picture with the D850 even if the sensitivity and noise settings were separated, so I will take up that matter soon.
It seems that this is the reason why the D810 and D850 Nikon examples and the D810 examples, including the catalog, give a sense of resolution and stereoscopic effect.
Since the D810 has less noise, it produces a solid tone without any noise reduction, and there is no gradation jump to the shadow.
summary
I started writing about comets, but it turned out to be a camera comparison article.
For the time being, let's return to the comet.
From now on, this Neowise comet, which is getting farther away from the sun and the earth, will continue until it disappears from the camera.
You can shoot from the window of your house, so it's pretty easy to shoot.
What kind of comet will appear next time?
I wish I could see a comet that would surpass Comet Hyakutake!
Even at such a moment, many comets that no one has seen will be flying while accelerating due to the gravity of the sun.
But I just want you to avoid hitting the earth.
Comet Shoemaker-Levy 9 collided with Jupiter in 1994.
Unfortunately, the moment of the collision was behind Jupiter, which is invisible from Earth.
The comet had already shattered into pieces due to Jupiter's gravity before it collided, and then collided with Jupiter.
At that time, the caretaker was staying in Daisetsuzan, Hokkaido, on location for a TBS program called Animal Fantasy Tengai.
At the moment of the collision, I was looking at Jupiter alone with binoculars from somewhere on Mt. Tomuraushi, not at the top of the mountain.
Behind the invisible Jupiter, he said, "I wonder if I've collided now!"
It seems that the impact of the collision was more intense than expected.
The brilliance of the flash at the moment of the collision was reflected on the surface of Jupiter's moon on the back side, and it seems that the brightness could be estimated.
After that, a mushroom cloud was formed in the clouds of Jupiter, and spots that could be observed with a small telescope were seen on the surface of Jupiter for a while.
If such a comet collides with the earth, will it return to the big start of life on the earth?
Life recession.
Will humanity survive and civilization remain?
What kind of life will prosper this time?
Will life with civilization reappear?
In such a future, will there be any evidence that humankind is alive today?
Somehow, I feel that only the Egyptian pyramids, which still remain as archaeological sites in the past, remain.
I don't want that to happen, but only delusions spread.
This time around here.
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Until the end Thank you for reading.
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