Jupiter this Fall (2021)
The night I took video to create these image was one of a handful I experienced this Summer with very good seeing (for Vermont).
I would say these are among the best images of Jupiter that I have produced, though I don’t plan to check. The fine scale seeing was steady enough that I could make out the disks of Jupiter’s Galilean moons visually. The large scale seeing, which causes the whole planet to jump around was much better than usual as well and helped minimize blurring.
The video clips used were all about 1 minute long (~3600 frames).
I lucked out with all the activity going on with Jupiter and it's moons starting with visibility of the Great Red Spot. Later the ingress of Europa on the disk about 10:45 PM, the ingress of Europa’s shadow at 12:14 AM and finally Io joining up with Ganymede for a family portrait.
The Red Spot and Europa (right edge of disk) 2021-09-19, 10:50 PM EDT, 10” f/5.6 Newt., 2x Barlow, 24mm eyepiece, Canon HF21 camcorder at 15x optical zoom. Stack of 1350 video frames.
Nice images Paul. I took a couple as well. I'll have to post them.
A contribution to this discussion from a couple of weeks ago. Not very good as I shoot over my house and the air is very turbulent.
Taken early morning. I got home a little after 3 AM after a night at the Hinesburg Observing Site. We had 9 (or 10, I may have missed one) members show up last night. I got the impression everyone had a good time. Before going up I had opened the shed for my "big" 10 inch scope in case I wasn't wiped out by the time I home it would be ready to go. I ended up spending another 2 hours at my backyard observatory viewing and imaging Jupiter, still tiny Mars and the waning crescent Moon. I was hoping for betters seeing but it was definitely above average.
You could call this a retro image. Planetary imagers from the days of yore when we used film for taking pictures are probably familiar with the term "eyepiece projection". Back in the days when we used film one of best ways to get a large image of a planet was to use eyepiece projection. This is where an eyepiece is positioned between the telescope focuser and the camera. The lens for the camera is removed first (if the camera lens is left on it is called "afocal method". Even if you are not familiar with the eyepiece projection method you may be familiar with viewing the Sun by projecting an image of the Sun on a screen using an eyepiece in a small aperture refracting telescope. It's just like that only you replace the screen with the camera's imaging sensor. And for the planets you need a bigger telescope. It is amazing what these newer digital SLR cameras can do!
Taken at 4:15 AM EDT this morning. All 4 Galilean moons are visible (an advantage of using this method). From left to right; Callisto, Io, Europa and Ganymede. They appear much brighter in the telescope visually. The shadow, dark spot just left of the Great Red Spot, is from Europa. North is down in this image.
10" f/5.6, 1407mm f.l., eyepiece projection with a 15mm eyepiece, Canon T7i camera, 1/30 sec @ iso1600, single image processed. I haven't tried stacking any of the images I took and this may not be the best image. I have not calculated the effective magnification yet.
I was surprised to see the Red Spot appearing to be inside a larger oval. I was also surprised to see a small reddish spot in the North Equatorial Band (lower dark band) (remember North is down in this image).
First image has been processed the 2nd is unprocessed.
Great images, Everybody!
Got home late last night and it was clear, to my amazement! I thought I'd give 'planetary' a try with my very limited equipment.
Sky-Watcher 150P Classic (1200mm fL, F/8) -- Dobsonian mount
Baader Mark IV zoom (at 24mm fL) with Tele Vue PowerMate (2x)
Canon SL3 (250D) - 1920x 1080, 60 fps; roughly 2,500 frames
Software: PIP, AS!3, Registax, and Photoshop (only to increase the exposure/visibility of Jupiter's moons seen in the photo: Io, Europa, and Ganymede)
I think I over- sharpened the image in Registax a bit.
I really posted this to ask a question of those of you who do planetary imaging regularly. Given that I don't have a Goto/tracking capability on this 150P and have to track manually, and this is about the highest magnification I can go without over-extending my 'reach' on this system, do you think it's worth investing in a planetary camera? (I was looking at a ZWO ASI585MC) I really don't know if the image quality will be better with a dedicated planetary camera that has better SNR than my Canon SL3 and a also has a higher frame rate (max about 95 fps). I thought I'd ask those of you who know more about it!
Finally responding-
Very nice image. Even with the somewhat low resolution due to the image scale you have a surprising amount of detail. Viewing at the image without magnifying it one can see fine details at the limit of the resolution. You don't see that in my images above. Mine look soft. Do you know what the exposure time is?
Sounds like you are using eyepiece projection as I did on my last image. You may want to try upping the f.l. on the zoom eyepiece a little bigger image scale (oh yea, I see you mentioned you are pretty much at the limit of your manual tracking will accommodate). If the camera has a digital zoom and you only want to image Jupiter try using that (ditto here on your system tracking limits). If you do the calculation, you will find the for a 24Mp camera shooting HD video (1920x1080 px) you will get the highest resolution at 3x digital zoom (at 3x you are using ~2000x1000 pixels from the center of the sensor rather than down sampling the 6000x3000 pixels of the full sensor) And of course since it's digital zoom the brightness is not reduces. I do this for closeup videos of the Moon.
To your question. I don't have experience with dedicated planetary imaging cameras. They could do better, but not by a lot. Atmospheric seeing is our primary limit here in Vermont and your manual tracking is another. If it is due to the exposure time being too short and causing blurring than, yes, a dedicated planet imager could help as it would likely be able to be operated at a shorter exposure time.
I would suggest experimenting with what you have some more. Because you are stacking lots of images you may be able to use a shorter exposure with this camera and still get enough signal to noise (S/N) to get better results.
Finally responding-
Very nice image. Even with the somewhat low resolution due to the image scale you have a surprising amount of detail. Viewing at the image without magnifying it one can see fine details at the limit of the resolution. You don't see that in my images above. Mine look soft. Do you know what the exposure time is?
Sounds like you are using eyepiece projection as I did on my last image. You may want to try upping the f.l. on the zoom eyepiece a little bigger image scale (oh yea, I see you mentioned you are pretty much at the limit of your manual tracking will accommodate). If the camera has a digital zoom and you only want to image Jupiter try using that (ditto here on your system tracking limits). If you do the calculation, you will find the for a 24Mp camera shooting HD video (1920x1080 px) you will get the highest resolution at 3x digital zoom (at 3x you are using ~2000x1000 pixels from the center of the sensor rather than down sampling the 6000x3000 pixels of the full sensor) And of course since it's digital zoom the brightness is not reduces. I do this for closeup videos of the Moon.
To your question. I don't have experience with dedicated planetary imaging cameras. They could do better, but not by a lot. Atmospheric seeing is our primary limit here in Vermont and your manual tracking is another. If it is due to the exposure time being too short and causing blurring than, yes, a dedicated planet imager could help as it would likely be able to be operated at a shorter exposure time.
I would suggest experimenting with what you have some more. Because you are stacking lots of images you may be able to use a shorter exposure with this camera and still get enough signal to noise (S/N) to get better results.
Thanks so much for the input, Paul! Yes, I also used eyepiece projection. (Have you ever tried afocal/digiscoping? I guess that would require more adapters.) I didn't record the exposure time on the night I recorded the planetary images, but I just turned on my DSLR and since I don't think I changed anything after that imaging session, it looks like 1/25" @ 800 ISO.
I'm going a little crazy trying to reconcile all the different ZWO planetary imaging cameras, to be honest. Using my current reflector at 1200mm FL + 2x TV PM, it looks like I'd ideally need a camera with about a 2.6 micron pixel size for 0.25"/pix. (I'm assuming average seeing for the majority of the time, but I'm not sure if that's the best thing to do around here.) With my Canon DSLR (3.72 micron pixel size), I'm at about 0.31"/pix, which is optimal for exceptional, but not OK/poor seeing.
So, to be honest, aside from a higher frame rate with a dedicated planetary camera, I don't think there would be a great advantage to buying one. I will most likely do as you suggested and test some different combinations using the equipment I have -- at least until I learn more about this and can understand this a little better.
I was using a guide from High Point Scientific to get an idea about this (Choosing the Best Planetary Camera | High Point Scientific), an article from Starizona (Planetary Imaging — Starizona), and also using astronomy.tools for the calculators. So I'm bascially drowning in data I don't fully understand yet! %~/
Thanks again, Paul. I appreciate your reply and your advice.
Recently took the next baby step up the astrophotography mountain and started stacking with frames from short videos. The nice thing about just starting out is that the curve is flat enough you can make good progress with modest effort. First pic was my first attempt, the source being a 30 second video from August 19th. Second pic is my second attempt, the source being a 1 minute video captured August 27th. Captured with a Pixel 3 android phone clamped to my Celestron NexStar Evolution 6". I used PIPP to convert the phone MP4 to raw AVI. AutoStakkert for the stacking. PhotoShop Elements for level adjustments.
The 2nd photo and 2nd session of stacking.
The 2nd photo and 2nd session of stacking.
Nice photos with a Pixel 3, Scott! Have you tried Registax 6 (free) for your post AS!3 and pre-Photoshop processing? The wavelet functions in there are really good and might be able to bring out some detail in your images. (I'm still learning how to use them, so I can't give you much advice other than to say give it a try.)
It amazes me what you can do with a mobile phone in terms of photography!! Have you used the Pixel 3 for any Milky Way shots? I'm curious how it performs.
Greg
Nice images by all!! Planetary imaging is a whole different game from deep sky!
Terri
@greg-erianne You inspired me to dust-off my RegiStax install, watch a couple of tutorials, and take another look at my Jupiter video.
There's some black box magic and knob frobulating going on, but this image is PIPP/AutoStakkert/RegiStax, with no PhotoShop touch up.
I was finally able to image the GRS on Jupiter last night! The seeing was much better than it has been (sorry, Terri!), so I didn't really sharpen much at all. Still looks a little blurry to me, but I had to resist the urge to sharpen more.
Didn't get Mars or Saturn, though. Too busy ironing out problems with the nebula I was trying to capture at the same time.
