Great Conjunction of Jupiter and Saturn

stevelee

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Does anybody know the exact real focal length of the 100-400mm II zoomed to nominal 400mm and focused at infinity? (I realize it is somewhat less than 400mm when focused close.) I’m unsure how to go about it anyway, but I would need to know that to figure the angular distance between the planets give the distance in the image. Any help or suggestions would be appreciated.
 
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stevelee

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Jul 6, 2017
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I haven't gone through my pictures from this evening yet. I think this one might be the most interesting if not as good technically as some (I hope). Saturn doesn't look as good as in my pictures from Saturday night. I bracketed exposures, so maybe my best version will be a composite. The plane flying through makes it interesting. In the Raw file you can see three moons of Jupiter clearly. You can probably make them out in the JPEG. 5:56pm EST. 6D2 EF 100–400mm II at 400mm f/8 ISO 3200 for 1/15 sec. I didn't do much in ACR to enhance, mostly darkened the sky a bit. It was about 15 minutes before nautical twilight.

IMG_3360.jpg
 
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I haven't gone through my pictures from this evening yet. I think this one might be the most interesting if not as good technically as some (I hope). Saturn doesn't look as good as in my pictures from Saturday night. I bracketed exposures, so maybe my best version will be a composite. The plane flying through makes it interesting. In the Raw file you can see three moons of Jupiter clearly. You can probably make them out in the JPEG. 5:56pm EST. 6D2 EF 100–400mm II at 400mm f/8 ISO 3200 for 1/15 sec. I didn't do much in ACR to enhance, mostly darkened the sky a bit. It was about 15 minutes before nautical twilight.

View attachment 194713
Really nice image Steve!

Unfortunately I had cloudy and unclear atmospheric conditions so took two blobs of nothingness!
 
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SteveC

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With greater exposure and magnification, you can see four moons, with Ganymede looking almost like a bump on the end of Jupiter. I confirmed the positions from Sky and Telescope's web site.

View attachment 194715

It's one of the perversities of the universe that in order to get the Galileans (kudos by the way!) you have to blow out Jupiter (and in this case Saturn is along for the ride and gets blown out too).

What I would do to focus is flip the screen out, dial up the ISO to max, magnify and use the Galileans to focus with; when they became points, I was focused (and yes, I was manually focusing). I'd then dial the ISO back to what I was using (roughly 1000, depending on the extender I had on if any), and the Galileans would of course disappear, but I could take the shot. I was more interested in the planets themselves, since that was what was unusual at the time.

I expect I'll someday do a composite of Jupiter plus Galileans.
 
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Hello everyone!

Yesterday was an awesome day to witness and photograph Saturn and Jupiter conjunction with a super-tele lens. I was worried that the clouds may roll in but gods were kind! It was also the first time that I shot with a super tele (Canon 600 mm F4 IS + 1.4xTC) and I can now understand the efforts put by wildlife photographers. I am pleased with my entire experience although in hindsight I should have used a crop sensor camera instead of EOS RP. I have also shot the moon as I had the opportunity to do it.

The Saturn-Jupiter conjunction image is heavily cropped while the moon image is cropped to taste. Posted photos are SOOC and I am impressed with the details resolved by the equipment.

Comments and feedback are welcome.

Gear used: Canon EOS RP, Canon 600 mm F4 IS, 1.4xTC (II?)

Jupiter-Saturn Conjunction: ISO 3200, 1/30 s, f5.6
Moon: ISO 1600, 1/500 s, f5.7

crop_jupiter_saturn.JPG



IMG_1717_crop.JPG
Regards
Suman
 
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stevelee

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It's one of the perversities of the universe that in order to get the Galileans (kudos by the way!) you have to blow out Jupiter (and in this case Saturn is along for the ride and gets blown out too).

What I would do to focus is flip the screen out, dial up the ISO to max, magnify and use the Galileans to focus with; when they became points, I was focused (and yes, I was manually focusing). I'd then dial the ISO back to what I was using (roughly 1000, depending on the extender I had on if any), and the Galileans would of course disappear, but I could take the shot. I was more interested in the planets themselves, since that was what was unusual at the time.

I expect I'll someday do a composite of Jupiter plus Galileans.
Last night I kept the aperture and ISO the same and kept changing the shutter speed to bracket. I hope to have a good exposure of Saturn in there somewhere. I would refocus occasionally on the screen at 10X. All the while I was chatting with neighbors who had come out to the same spot to view the conjunction. There is an open area three houses away from mine, so it was like an unplanned viewing party. I let folks look at the 10X screen. Focusing on the moons worked great. If I can do a decent composite, I’ll post here.
 
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It's one of the perversities of the universe that in order to get the Galileans (kudos by the way!) you have to blow out Jupiter (and in this case Saturn is along for the ride and gets blown out too).

What I would do to focus is flip the screen out, dial up the ISO to max, magnify and use the Galileans to focus with; when they became points, I was focused (and yes, I was manually focusing). I'd then dial the ISO back to what I was using (roughly 1000, depending on the extender I had on if any), and the Galileans would of course disappear, but I could take the shot. I was more interested in the planets themselves, since that was what was unusual at the time.

I expect I'll someday do a composite of Jupiter plus Galileans.

Jupiter is brighter than Saturn and so, a composite would help (https://earthsky.org/astronomy-essentials/great-jupiter-saturn-conjunction-dec-21-2020). I too have noted this while photographing the conjunction. The small dots are Jupiter's moons.
Jupiter_Saturn_Moons.JPG

Regards
Suman
 
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SteveC

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Jupiter and Saturn shot with the R5, 100-400L V III and 2X extender.
View attachment 194764View attachment 194765

I got nearly identical results with just about the same gear (no grip). That is, after I fired probably a hundred shots, in quick bursts (using electronic shutter and a whatchumacallit, the cable release), and rejecting all but five of them. I also tried no extender and a 1.4x.
 
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