Jupiter - better than expected

[Stu]

Just warming up with a cup of tea after an unexpectedly reasonable session on Jupiter (let's not over blow it 🤣).

My pier mounted GP-DX is not ideally positioned to see Jupiter down so low, so I popped the Sphinx down at the bottom of the garden where there is a better view back over the houses. I decided to risk the Mewlon, hoping that the seeing would be better than last night. GRS was showing as visible so I was hoping to pick it up long before it got dark. I think I first spotted it in binoculars at around 9.30pm, and got the scope centred on it. Initial views were not promising, although I could just about see GRS and Io about to drop behind the planet.

I persevered on and off for 2.5 hours, just packing in a few minutes ago and have been rewarded by the best views I've had this opposition. That is not saying an awful lot, but they were better than I expected, improving nicely as the night cooled and the planet got higher.

I stuck with x164 through the binoviewers, and as things improved, GRS became more distinct as it headed toward the limb. There was a pleasant amount of belt detail, some festoons off the NEB and distinct colour to the bands. Atmospheric CA was there when the seeing worsened but generally it was unobtrusive.

Didn't look at much else, just the Double Double and some alignment stars, but 'twas great to get out there and to be rewarded with some decent views.

Hope you are enjoying it if you are out.

PS Saturn was RUBBISH 🤣🤣, no doubt it will improve a little as it gains height, but I need my bed!!

[SIDO]

Patients and consistent observation wins the night again, this hobby has always reminded me of fishing in that regard.

Cool you had a "bit" of success Stu, I rolled the dob out last night but unrelenting haze to the south with strorms passing through northern Illinois prevented using it, will try again tonight...

Edited June 28, 2019 by SIDO

[geoflewis]

Well done Stu,

I also had my first session this year on Jupiter tonight using my C14. I set up to try some video captures, but started and finished with some visual. The GRS was on its way to exiting when I started, but I had some lovely views of it using a 40mm eyepiece with the x2 TV Powermate and ADC also in train (approx x200 magnification) - the later makes a huge difference with Jupiter at such a low altitude from my location, removing the red/blue fringes. Io was right on Jupiter’s limb just before being occulted - really a very enjoyable view. I tried a 25mm eyepiece, but x400 was too much for the conditions.

I then swapped the eyepieces for my ASI120MM-s camera and ran a bunch of R-G-B and IR AVIs. I did a few test processing with AS3! & Registax and as expected, nothing much to write home about, but I’ll work through them the next few days to see what I can extract.

Towards the end of the session I noticed that the images were getting dim and inspection of the corrector plate revealed that it was dewing over. More concerning I could see that the primary was also mirror fogged. I had been running the fans to stabilise air currents in the OTA and am wondering if they had sucked in moist air which settled on the mirror. Anyway, nothing to be done tonight, so I packed up, set the dehumidifier running in the Obs and will check everything out tomorrow.

It was fun while it lasted....

Geof

[jetstream]

Do I ever like that Mewlon Stu, what a scope! Great observing with some nice detail

[Ibbo!]

Escorted jupiter into e garage and now doing samefor saturn.

Damper than last couple of outings but seeing vastly improved.

[Stu]

7 hours ago, geoflewis said:

Well done Stu,

I also had my first session this year on Jupiter tonight using my C14. I set up to try some video captures, but started and finished with some visual. The GRS was on its way to exiting when I started, but I had some lovely views of it using a 40mm eyepiece with the x2 TV Powermate and ADC also in train (approx x200 magnification) - the later makes a huge difference with Jupiter at such a low altitude from my location, removing the red/blue fringes. Io was right on Jupiter’s limb just before being occulted - really a very enjoyable view. I tried a 25mm eyepiece, but x400 was too much for the conditions.

I then swapped the eyepieces for my ASI120MM-s camera and ran a bunch of R-G-B and IR AVIs. I did a few test processing with AS3! & Registax and as expected, nothing much to write home about, but I’ll work through them the next few days to see what I can extract.

Towards the end of the session I noticed that the images were getting dim and inspection of the corrector plate revealed that it was dewing over. More concerning I could see that the primary was also mirror fogged. I had been running the fans to stabilise air currents in the OTA and am wondering if they had sucked in moist air which settled on the mirror. Anyway, nothing to be done tonight, so I packed up, set the dehumidifier running in the Obs and will check everything out tomorrow.

It was fun while it lasted....

Geof

Thanks Geof, sounds like you had a decent session. I have tried an ADC twice and not found them to make enough difference for me to be worth the extra setup time. I also use binoviewers and it just gets a bit much to fit in the optical path so you can easily adjust them. Great that you see such benefit from yours though, I wonder if it makes more difference with the extra aperture?

I have had a few experiences, mainly with maks, where running the fans in humid air just makes things worse. I've had the triple whammy of primary and both sides of the corrector fully dewed up before. Now that does dim the view a tad 🤣🤣

[Stu]

6 hours ago, Ibbo! said:

Escorted jupiter into e garage and now doing samefor saturn.

Damper than last couple of outings but seeing vastly improved.

Funny 😀. I know that feeling, I have to be down the bottom of my garden to get it above the roof top early on, and then says hello to the tree a bit later on.

I should have stayed up for Saturn, just didn't want to feel too exhausted today.

[Stu]

8 hours ago, SIDO said:

Patients and consistent observation wins the night again, this hobby has always reminded me of fishing in that regard.

Thanks very much. Yes the detail definitely got better with longer spells of observing, up to half an hour at a time I guess. Have the scope tracking well and being seated makes it much easier to concentrate on the detail and catch the moments of good seeing.

[John]

Great report Stu - pretty much saves me posting one because I was on the same target last night with my Tak FC100 with very similar results. Once the GRS had rotated out of view I noticed a couple of festoons coming from the S edge of the NEB trailing diagonally across the N section of the Eq zone. 

Only downer was that I was clouded out a little later when I had just started on some brighter DSO's with the 12 inch dob

Definitely the best Jovian views of what has been a frustrating season on that target thus far. Hopefully more to come !

 

[Stu]

5 minutes ago, John said:

Great report Stu - pretty much saves me posting one because I was on the same target last night with my Tak FC100 with very similar results. Once the GRS had rotated out of view I noticed a coupld of festoons coming from the S edge of the NEB trailing diagonally across the N section of the Eq zone. 

Only downer was that I was clouded out a little later when I had just started on some brighter DSO's with the 12 inch dob

Definitely the best Jovian views of what has been a frustrating season on that target thus far. Hopefully more to come !

 

The festoons were nice weren't they? Wasn't expecting the seeing to be as stable as it was so am very glad I went out. Scope is still out under cover so can have another go soon.

I may try my Tak next time. I was in two minds which to use last night. I suspect the results were probably in favour of the Mewlon in the end, very nice colour in the bands and GRS plus the larger exit pupil helps with floaters at higher powers. I guess the resolution would be better too but down that low it may well not be any better. Will try.

[steveex2003]

14 minutes ago, John said:

Great report Stu - pretty much saves me posting one because I was on the same target last night with my Tak FC100 with very similar results. Once the GRS had rotated out of view I noticed a couple of festoons coming from the S edge of the NEB trailing diagonally across the N section of the Eq zone. 

May I ask what mag(s) you found these views at, and with which type of EP? I understand the skill is observing, i'm just interested for reference. There were no views to be had down here last night sadly.

[Stu]

2 minutes ago, steveex2003 said:

May I ask what mag(s) you found these views at, and with which type of EP? I understand the skill is observing, i'm just interested for reference. There were no views to be had down here last night sadly.

From my side it it was x164, any higher and the seeing just would not support it and contrast was lost.

The two posts below show Jupiter in similar rotations where the belt detail and festoons are visible. Obviously I'm not saying this sort of detail was visible but the larger features were. I also caught one of the lighter belts in the Northern polar region too when the seeing allowed.

 

[John]

22 minutes ago, steveex2003 said:

May I ask what mag(s) you found these views at, and with which type of EP? I understand the skill is observing, i'm just interested for reference. There were no views to be had down here last night sadly.

For me, 140x - 150x was giving the clearest views with decent contrast.

Even at 90x most of the details were seen but 180x was just too much and the contrast suffered. I was using a 100mm refractor last night on Jupiter.

[steveex2003]

Thank you gents.

[Size9Hex]

Really enjoyed reading your report. Glad you had some good views. Takes some effort staying up to observe at this time of year!

[geoflewis]

4 hours ago, Stu said:

Thanks Geof, sounds like you had a decent session. I have tried an ADC twice and not found them to make enough difference for me to be worth the extra setup time. I also use binoviewers and it just gets a bit much to fit in the optical path so you can easily adjust them. Great that you see such benefit from yours though, I wonder if it makes more difference with the extra aperture?

I have had a few experiences, mainly with maks, where running the fans in humid air just makes things worse. I've had the triple whammy of primary and both sides of the corrector fully dewed up before. Now that does dim the view a tad 🤣🤣

Hi Stu, yes from my experience the ADC comes into its own at the higher magnifications possible with larger apatures. When I tried to push themagnification up I could still see blue/red fringing even with the ADC prism set to max. Without the ADC Jupiter loked like one of those 3D images without the 3D glasses.

I just checked my C14 OTA and all is clear now, which is good. I've not experienced fogging on the inside of the scope previously and of course there's no easy way to clear that, unlike the outside of the corrector plate where a quick blast with a hairdryer generally does the job. I think the dew point was quite high last night as everything was wringing wet. Lesson learnt - I need to be a bit more judicious when using the fans in humid conditions - pity as they really do stabilse the image....😖. Cheers, Geof

[JeremyS]

3 hours ago, Stu said:

I may try my Tak next time.

A side by side comparison of the Tax 100 and Mewlon 210 on Jupiter would be very interesting @Stu

[steveex2003]

5 hours ago, John said:

For me, 140x - 150x was giving the clearest views with decent contrast.

Even at 90x most of the details were seen but 180x was just too much and the contrast suffered. I was using a 100mm refractor last night on Jupiter.

Where you using a preferred narrower angle EP in the Frac? 

[steveex2003]

By which i mean fewer or more lens groups etc. The detail you convey earlier has me just wishing I could do the same, and I spend hours looking at Jupiter.
Again, I know skill of observing, and luck of the conditions are key.

Edited June 29, 2019 by steveex2003

[Stu]

14 minutes ago, steveex2003 said:

By which i mean fewer or more lens groups etc. The detail you convey earlier has me just wishing I could do the same, and I spend hours looking at Jupiter.
Again, I know skill of observing, and luck of the conditions are key.

Which scope do you use Steve?

[steveex2003]

Bortle 4-5 skies dependant on location 

*Edit, misread. I was using the 120.

Edited June 29, 2019 by steveex2003

[steveex2003]

I have a suspicion that the answer is try harder

[John]

4 hours ago, steveex2003 said:

Where you using a preferred narrower angle EP in the Frac? 

I was mostly using a zoom eyepiece combined with a barlow lens. Both of good quality but lots of glass involved of course (my guess = 7-8 elements in total). I also used Pentax XW eyepieces in 5mm and 7mm. Those are 8 element eyepieces. I used to use orthoscopics a lot but I prefer a bit more viewing comfort and a wider angle of view these days.

 

[Stu]

6 hours ago, JeremyS said:

A side by side comparison of the Tax 100 and Mewlon 210 on Jupiter would be very interesting @Stu

Your wish......

In the blue corner, Tak FC100 and in the greenish corner the Mewlon 210. Both with binoviewers, although I've got a bit of work to do to equalise the mag.

Obviously no idea what the seeing is going to do tonight, but I may be able to catch the Io shadow transit earlier on, at least I know where Jupiter will be now at that time! 

[JeremyS]

38 minutes ago, Stu said:

your wish......

In the blue corner, Tak FC100 and in the greenish corner the Mewlon 210. Both with binoviewers, although I've got a bit of work to do to equalise the mag.

Obviously no idea what the seeing is going to do tonight, but I may be able to catch the Io shadow transit earlier on, at least I know where Jupiter will be now at that time! 

Looking good Stu! 🙂