Right before the Christmas holiday there was the big conjunction of Jupiter and Saturn, an event that occurs every 800 years and had a nice run-up. For me, I often walk the dogs around sunset and we go down this stretch of open area where a gas pipeline is buried and therefore there is a big “no construction” easement around it. This also happens to be next to a flood pond, where here in Austin as the seasonal rains come, we have flash flooding due to the hard packed ground/clay so there’s flood channels built in and around the various HOAs to direct water during these times and store the excess to prevent flooding next to homes and streets. The end result being a big open space of few trees where I can get a nice view of a large portion of the sky. I’ve used this area for eclipses, meteor showers, and even trying to get a view of Comet NEOWISE when that passed by earlier this year. So, as the conjunction neared I had a pretty good view each night with the nice Austin weather and my dusk dog walks. It would have been cool to get a nightly shot from roughly the same area and show the event unfolding over the nights but that just wasn’t in the cards for me this time around. I did, however, know that I wanted some some shots, and so with a few days before the peak of the event I started experimenting with different setups to try to get a good shot, and I was lucky I did because the night of the peak we did have clouds roll through so only right at sundown was it even visible before the clouds covered it for the evening.
In the end I used three different setups and I wanted to talk about the pros and cons of each with the shots from each so that myself and others could make good decisions for next time. Here’s the different setups:
- Nikon Z7 with 85mm fixed lens on a tripod.
- Nikon Z7 in prime focus on a 10” SCT without star tracking
- Nikon D700 with a 70-200mm Tamron on a tripod.
First the Nikon Z7 with 85mm. For starters the 85mm is in the new S-line lenses that fit the Z7 Mirrorless camera, unfortunately this is highest zoom lens I have for the Nikon Z7, I have some of the old F mount lens that can be used with the adapter on the new Z mount, but nothing larger than the 85mm (with one exception we’ll discuss later: the 70-200 Tamron). There is a 105mm in the S-line due out in 2021 that I will like to get my hands on, but it is not yet released. So, using just a tripod and remote shutter cable I setup the Nikon Z7 with the 85mm and dialed in the focus and exposure settings.
Here’s one of the better ones:
In the end I was happy with the shots I got but they are heavily zoomed/cropped. Jupiter and Saturn stand out and I do like how I was able to capture the Galilean Moons.To sum up:
- Good exposure
- Galilean Moons
- Heavily zoomed/cropped.
On the nights before the peak of the event I did roll my LX200 10” Schmidt Cassegrain telescope out of the garage and into the street for some shots with the Nikon Z7 at prime focus. I even tried some shots with a light pollution filter in place, since the alignment/geometry put it pretty close to a street light. I have a tracker on my setup, there’s a large 70mm finder scope made by Orion Telescopes & Binoculars that has a CCD, the Orion Autoguider, hooked up to it and that interfaces not only to the telescope’s motors, but also an old MacBook I have running windows (because of course the software is windows only). However, there is an issue with this setup and the cable connectors might not be correct and sending the right commands/pulses on the right pins. Basically, the camera is hooked up, stars in the field drift the autoguider detects this and is suppose to send commands to move the telescope to compensate, but as of right now the telescope does not appear to be responding to those movement commands. And if you’ve ever used a medium to high power telescope one thing is clear: the sky is in constant motion! This presents quite the challenge for photography, you can’t get the objects to sit still so you either need the tracking or you need to compensate by bumping up ISO and shortening exposure times to reduce that motion blur.
I felt I struggled a lot with this and even though I was able to dial in the focus, I wasn’t able to remove that motion blur or get an exposure at the right level where the moons of both Jupiter or Saturn are visible. When using the telescope with my eyes, rather than camera, I can easily see the bands of Jupiter and the rings of Saturn, but these were not captured well in the images at all. It is going to be high priority in the near future to test that tracking and get it working if I expect any sort of quality images from the telescope. So to sum up this setup:
- Highest magnification, can get a good framed shot with minimal to no zoom or crop.
- Heavy, lots of equipment to roll out and not lose or break: telescope, autoguider, laptop, camera, power/battery.
- The sky is constantly moving, tracking is needed
- Tracking and the telescope takes a lot of time to setup, so larger time commitment/overhead.
Finally, our last setup, this was on the day of the peak right after sunset and right before the clouds rolled in ruining the view. For this, I used my old camera, the Nikon D700, and a Tamron lens.
Once I dialed in the exposure and settings I got a couple of decent shots, but the clouds and haze in the air were already starting to affect the images. Also, there is a big difference in resolution on the Z7 compared to the D700, so once again it took some heavy zoom & crop to get close to something usable.
And in the end, even though this was the higher powered lens compared to the Z7, the images weren’t as great, I think for a few reasons. First, as mentioned the clouds and haze were already rolling in. Second, I think with the exposure settings I was using the mirror slap up and down may have cause some vibration, I did not do the mirror lockup when taking these shots and that might have been an oversight. Finally, I think the Z7 is obviously a more superior camera, and it should be, the D700 was released in 2008 and the technology has continually improved.
In the end, using the Telescope is definitely the best choice, as long as the tracking is somewhat working and you have the time. The Z7 on its own does a very good job and eventually adding a more higher powered zoom there will help.