Great Conjunction of Jupiter and Saturn

Mar 25, 2011
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In just a few weeks, Jupiter and Saturn will appear very close to each other in early evening. Who is going to photograph this? I'd assume a telescope is best but I don't have one. How about my 100-400L plus a TC or two? Do I need a motorized mount?

Is it even practical?


Before the end of 2020, great conjunction of Jupiter and Saturn | Astronomy Essentials | EarthSky
I’ll probably give it a go after getting some fun time in with comet Neowise. I think you will have pretty limited time to get your shot so far north, down here in Florida I’ll get a bit more time but a lot more light pollution. I’ll use my 300 f2.8 with and without TC’s.
 
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tron

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I guess it depends if someone wants to include landscape too. If not, my "record" is managing to balance for a couple of times (a few seconds each) a 5DIV with 300 2.8II with 2XIII to an Astrotrac. It allowed me to shoot the moon eclipse with an ISO ten times less than without any mount. I had my hands in standby to catch the combo though :D I loved the result and felt sorry for not using it a few minutes earlier than I did, instead of trying to shoot the eclipse with my 500mmII on a tripod (and high ISO)!
 
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LDS

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Planets can be quite bright (depending on their actual distance from Earth, and atmosphere cleanness and darkness) and they can be shot without a motorized mount if the lens is bright enough. I took some photos of Jupiter last July (when it was close) at 1/90 - 1/125s f/11, 400 ISO, with a 400/5.6 mm to get a readable object (making the Galilean satellite visible required a longer exposure, 1/15s f/5.6 1600 ISO, but the planet is overexposed). I did a lot f bracketing. It was a polluted environment.

With a 400mm anyway the planet disc is tiny, less than 30 pixel across with a 5DIII (a better sensor will yield something more). A 2x converter may help greatly. You can try with two TCs too, and see if the image is still good enough. Usually, with telescopes, high magnifications are used for planets, well above what a telephoto con reach.

Focusing must be very careful - it's better if the camera/lens are left to reach the ambient temperature. A very stable mount is essential, no vibrations. Raised mirror (or no mirror, of course). The open shutter and black card trick is a bit difficult with short exposures. An electronic shutter might help, but never had a chance to try one.

That's to take planets images. To take an image of the conjunction with a nice landscape as a backdrop is a different matter, but in this kind of images planets are just bright dots.

I did it more to see what the system could yield than to get something nice/useful, anyway. But I'll try to get images ot the event anyway.
 
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Mar 25, 2011
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The two will be a lunar width apart.

Even with the 600/4 and 2x TC, the moon is only about 2/3 of the height of the photo, so your 400mm x 2 would have them about half a full-frame sensor's height apart. I think that's about the shot you'd want.

That does not jive with what i'm reading. The moon width is about 31 arc minutes, the separation will be 6.1 arc minutes. The diameter of Jupiter plus Neptune is about 36.8 arc seconds or 0.6 arc minutes. That means the combination will be about 6.7 arc minutes in diameter which is about 0.22 the diameter of the moon.

My 100- 400mmL f/5.6 would need a 3X plus a 2X TC or 2400mm equivalent to fill the frame height to 90% and I'd have a effective aperture of about f/32 which means a fairly long exposure at a reasonable ISO but doable.

Obviously, you are going to need far more than 2400 mm to fill a FF sensor to even half the sensor height with the Jupiter/Neptune conjunction. One half the sensor width would take even more. I did not bother to calculate it because the effective aperture of such a lens would be very tiny and a very long exposure. A camera lens that long is also nonexistent except for telescopes.

One suggestion is to take a video and stack the frames. My R5 will take 4K or 8K video and I might be able to stack frames. That would give a lot more pixels. Its overcast tonight or I could play with a video and see what I get. 1/5 the size of the moon gets pretty small but is huge compared with the size of a planet alone.

My PowerShot Zoom arrives tomorrow. That might be something to easily get a idea as to what's possible with a real camera and I would not need to drag out all my heavy duty stuff. I don't hold much hope for it to be useful in the dark, I think that trial would easily confirm that. It might see the moon though.

Here is a R5 photo of the moon at 2400mm. Its about 90% of the frame height.

Moon at 2400mm on R5 | Canon Rumors
 
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SteveC

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That does not jive with what i'm reading. The moon width is about 31 arc minutes, the separation will be 6.1 arc minutes. The diameter of Jupiter plus Neptune is about 36.8 arc seconds or 0.6 arc minutes. That means the combination will be about 6.7 arc minutes in diameter which is about 0.22 the diameter of the moon.

My 100- 400mmL f/5.6 would need a 3X plus a 2X TC or 2400mm equivalent to fill the frame height to 90% and I'd have a effective aperture of about f/32 which means a fairly long exposure at a reasonable ISO but doable.

Obviously, you are going to need far more than 2400 mm to fill a FF sensor to even half the sensor height with the Jupiter/Neptune conjunction. One half the sensor width would take even more. I did not bother to calculate it because the effective aperture of such a lens would be very tiny and a very long exposure. A camera lens that long is also nonexistent except for telescopes.

One suggestion is to take a video and stack the frames. My R5 will take 4K or 8K video and I might be able to stack frames. That would give a lot more pixels. Its overcast tonight or I could play with a video and see what I get. 1/5 the size of the moon gets pretty small but is huge compared with the size of a planet alone.

My PowerShot Zoom arrives tomorrow. That might be something to easily get a idea as to what's possible with a real camera and I would not need to drag out all my heavy duty stuff. I don't hold much hope for it to be useful in the dark, I think that trial would easily confirm that. It might see the moon though.

Here is a R5 photo of the moon at 2400mm. Its about 90% of the frame height.

Moon at 2400mm on R5 | Canon Rumors


Did you actually look up Neptune's arc width instead of Saturns? I ask because you said Neptune multiple times so it may have been intentional. It's Saturn that's going to be in conjunction with Jupiter, not Neptune.

You are, no matter what correct about the overall size of the phenomenon. I even saw a graphic somewhere showing the two planets in a (simulated) telescope view, with far more magnification than you'll get on a 400mm lens.
 
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stevelee

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I have an old telescope and somewhere an adapter that worked with my film camera. It might work with my 6D2. I haven’t used the telescope since I moved here 11 years ago. There is too much light pollution to see much. But planets are a different story. Still I think it will be far enough west that I’m not going to have a clear view from my yard, and the old clock drive needs plugging in. So too many variables and too much trouble to try something for the conjunction itself. A good picture will show both planets, Saturns rings, and some of the bigger moons. I’ll let others take those shots.

My plan is to take a pictures around the 15th, weather permitting. Some time about then the two planets will form a triangle with the crescent moon. I’ll shoot that with my 100-400mm lens. I don’t have a TC. I will bracket exposures and probably stack. The moon is so much brighter than Saturn that I doubt one setting will work for both. The planets will be not much more than dots. I shot Mars with that lens, and it was a small red circle, obviously a planet and not a star. Maybe Jupiter will be similar. If I get something I think is interesting, I’ll post it here. In the meantime, I like seeing them get closer together each night that is clear.
 
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Did you actually look up Neptune's arc width instead of Saturns? I ask because you said Neptune multiple times so it may have been intentional. It's Saturn that's going to be in conjunction with Jupiter, not Neptune.

You are, no matter what correct about the overall size of the phenomenon. I even saw a graphic somewhere showing the two planets in a (simulated) telescope view, with far more magnification than you'll get on a 400mm lens.
I mistyped the planet, the arc sec is correct for Neptune. Its extremely tiny in the sky, not visible without magnification.

That gap between the two is nowhere near the size of the moon.
 
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SteveC

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I mistyped the planet, the arc sec is correct for Neptune. Its extremely tiny in the sky, not visible without magnification.

That gap between the two is nowhere near the size of the moon.

Yes, this is going to be quite a sight, naked eye, telescope, camera, you name it. Being able to see Jupiter and Saturn without having to move back and forth is an extremely rare treat.

I've recently tried photographing planets through my 100-400 with both the 2x and 1.4x teleconverters but got nothing but a white blur. When I tried Mars, it was a pale orange blur. I actually had much better luck a couple of years ago with my M6-II and a Tamron 18-400--the planets were at least recognizable, Jupiter having a hint of striping and Saturn's rings obvious and both had color.
 
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Hey calling @AlanF .... Time to break out the big gun with those tele converters !
I think he said overcast in Merry Olde England. It looks like lots of rain currently over a big North South portion of the country and the rest is likely overcast. We are overcast here as well, It is hopeful that the 19th might be clear, otherwise a little snow and lots of clouds.



weather.JPG
 
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stevelee

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I've recently tried photographing planets through my 100-400 with both the 2x and 1.4x teleconverters but got nothing but a white blur. When I tried Mars, it was a pale orange blur. I actually had much better luck a couple of years ago with my M6-II and a Tamron 18-400--the planets were at least recognizable, Jupiter having a hint of striping and Saturn's rings obvious and both had color.
I shot these at 400mm with no teleconverter. Mars is a 100% crop, shot handheld at f/6.3 for 1/400 second. The moon and Jupiter were shot at f/8 for 1/320 second. IS was on.
mars400.jpg

moonandjupiter.jpg
 
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SteveC

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I shot these at 400mm with no teleconverter. Mars is a 100% crop, shot handheld at f/6.3 for 1/400 second. The moon and Jupiter were shot at f/8 for 1/320 second. IS was on.
View attachment 194453

View attachment 194454
What was the ISO setting?

Anyhow, I may have identified two possible causes for my issue. I was using a 1/100th to 1/200th shutter speed and may have been suffering because of that (people have reported blurriness at those speeds with an R5). Going faster may help that, or switching to electronic shutter. The other issue could be that even though I was on a tripod I had IS on. I can still experiment tonight on Mars (Jupiter and Saturn have set by now).
 
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stevelee

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Moon and Jupiter shot was at ISO 3200. I couldn't find the Raw file for the Mars picture, so I don't know the ISO right off. Probably the same.

Here is a picture I shot in 2016 at 75 mm with my T3i. This is a composite, since the moon was overexposed in one shot, so I used the moon from a different exposure in the bracketing. This shows Jupiter, Saturn, Mars, and the moon. The moon is at ISO 200 and the planets at ISO 3200. It is reduced for posting here, but you can still make out the planets. If I can get this on a Rebel with a notoriously bad lens (75–300mm), you shouldn't have too much trouble doing better.

triangle.jpg
 
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Joules

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Anyhow, I may have identified two possible causes for my issue. I was using a 1/100th to 1/200th shutter speed and may have been suffering because of that (people have reported blurriness at those speeds with an R5).
If I can get this on a Rebel with a notoriously bad lens (75–300mm), you shouldn't have too much trouble doing better.
There is more than gear and settings to shooting the moon and planets. Another common and very impactful source of blur are disturbances in the atmosphere. Especially if the object you are shooting isn't right above you, you're looking through a lot of air that can wobble and distort the image in the process. It what maker's stars twinkle. If you observe the moon through LiveView it will be easy to judge how the 'seeing' is in a given night.

Ideally, you get lucky and just image on a very still night and wait until the moon / planet has risen sufficiently far above the horizon. Another strategy to combat this has already been described.

Take lots of pictures and let software Analyse them to combine and stack the sharpest sections of them all into one image with less noise and less impact from the atmosphere. The technique is called lucky imaging and is usually applied by taking an uncompressed video with a special type of camera.

I think on an R6 / R5 you are better off just using the electronic shutter 20 FPS burst mode until the buffer is full. That saves you from any forms of compression, or overheating and requires a little less processing power on the computer compared to the RAW video options.

Free software that does this is Autostakkert or Registax, for example.
 
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Mar 25, 2011
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There is more than gear and settings to shooting the moon and planets. Another common and very impactful source of blur are disturbances in the atmosphere. Especially if the object you are shooting isn't right above you, you're looking through a lot of air that can wobble and distort the image in the process. It what maker's stars twinkle. If you observe the moon through LiveView it will be easy to judge how the 'seeing' is in a given night.

Ideally, you get lucky and just image on a very still night and wait until the moon / planet has risen sufficiently far above the horizon. Another strategy to combat this has already been described.

Take lots of pictures and let software Analyse them to combine and stack the sharpest sections of them all into one image with less noise and less impact from the atmosphere. The technique is called lucky imaging and is usually applied by taking an uncompressed video with a special type of camera.

I think on an R6 / R5 you are better off just using the electronic shutter 20 FPS burst mode until the buffer is full. That saves you from any forms of compression, or overheating and requires a little less processing power on the computer compared to the RAW video options.

Free software that does this is Autostakkert or Registax, for example.
I think on an R6 / R5 you are better off just using the electronic shutter 20 FPS burst mode until the buffer is full. That saves you from any forms of compression, or overheating and requires a little less processing power on the computer compared to the RAW video options.

Free software that does this is Autostakkert or Registax, for example.

Perhaps someone can compare night sky photos of planets and post. If I could see the sky, I would. Noise might be lower in the 20FPS mode.
 
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SteveC

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There is more than gear and settings to shooting the moon and planets. Another common and very impactful source of blur are disturbances in the atmosphere. Especially if the object you are shooting isn't right above you, you're looking through a lot of air that can wobble and distort the image in the process. It what maker's stars twinkle. If you observe the moon through LiveView it will be easy to judge how the 'seeing' is in a given night.

Ideally, you get lucky and just image on a very still night and wait until the moon / planet has risen sufficiently far above the horizon. Another strategy to combat this has already been described.

Take lots of pictures and let software Analyse them to combine and stack the sharpest sections of them all into one image with less noise and less impact from the atmosphere. The technique is called lucky imaging and is usually applied by taking an uncompressed video with a special type of camera.

I think on an R6 / R5 you are better off just using the electronic shutter 20 FPS burst mode until the buffer is full. That saves you from any forms of compression, or overheating and requires a little less processing power on the computer compared to the RAW video options.

Free software that does this is Autostakkert or Registax, for example.

Unfortunately the Jupiter Saturn conjunction will not be directly overhead...but it's important to take the pictures as early as possible, before they get even closer to the horizon and MUCH more air comes between us and them.

On the other hand later at night is likely to be better because it's cooler and less thermal convection.

The idea of just filling the buffer in electronic shutter mode sounds promising, because any one shot is liable to be blurry thanks to our atmosphere, but there are occasional instants of clarity. (It's going to take a lot of work to step through and magnify each shot to look for the best ones, though!) I generally keep almost everything I shoot but in this case I'll be trashcanning a lot of shots; I do NOT want this to become the first >100GB shooting session on my NAS.
 
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