Jupiter with the GRS and (still tiny) Mars - 20.09 decent seeing

[ONIKKINEN]

Second attempt at planetary with a TS ONTC 10'' f/4 newtonian, APM coma correcting barlow and a 678MC. Shown at capture resolution for both. Secondary mirror was covered in dew long before i took either of these and the primary dewed over for the third time that night just after starting the Mars recording. I've no plan to fix the dew issue at the moment, i just hope winter sets in soon and the problem goes away with colder and less dew prone nights.

Jupiter is 4x 3min derotated. Have not had too much success with derotation before, but at least this time i dont think the image got worse so maybe i did it right.

Mars is 100k frames, focusing was at Jupiter. Just too small to make any calls on whether im in focus or not so decided to use Jupiter as a focusing aid instead.


Both images taken around 01:30-01:40 UTC.

-Oskari
 

[geoflewis]

Both are lovely images Oskari

[ONIKKINEN]

12 minutes ago, geoflewis said:

Both are lovely images Oskari

Thanks, i have to say i am surprised the milky secondary mirror did not have a catastrophic effect on quality. The blue channel is terrible, but neither planet has much of it so i think i got away with it this time.

[symmetal]

Both lovely images. 😊

What do you use to determine focus, and would Mars actually have a different optimum focus position than Jupiter especially when using barlows etc. 🤔 I just use a bahtinov mask on a nearby star and that seems fine to me even for the Moon. 😉

Alan

[tonyowens_uk]

Nice piece of imaging Oskari. As these were taken well into the morning, i can see that altitude of both Mars and Jupiter was decently high for you - above 32 degrees!

You obviously have excellent optics in your Newt to be turning in this level of detail from a 10" aperture, and you managed the focusing very well. As you mention, no contrast issues from the condensation on the diagonal, and nicely processed. Bravo!

[Kon]

Nice images Oskari. At this small size Mars and not perfect seeing, I also use Jupiter and tweak it a bit. You may want to add an ADC in the mix. There is one in classifieds UK on good price.

[ONIKKINEN]

50 minutes ago, symmetal said:

Both lovely images. 😊

What do you use to determine focus, and would Mars actually have a different optimum focus position than Jupiter especially when using barlows etc. 🤔 I just use a bahtinov mask on a nearby star and that seems fine to me even for the Moon. 😉

Alan

Thanks, i focus based on the live feed on the planet itself. I find that there is too much room for interpretation with bahtinov masks, and its easy to miss focus by quite a bit (and every micrron counts). What i do is rack the focuser in and out using the reducer knob on my diamond steeltrack and stop where its sharpest, or least worst when seeing is not that good. Then do minute adjustments to one direction, look at the feed for a minute or so, rinse and repeat and the best spot is found eventually. I dont think Mars has different focus from Jupiter, given that they are both at infinity and were reasonably close in the sky. Its just that Mars is 40 pixels in diameter... Its just impossible to have anything to look at to gauge focus, or so i've found. Its not too bad once we get closer to opposition, but at the moment its still a tiny 7'' disk of wobble and blur.

39 minutes ago, tonyowens_uk said:

Nice piece of imaging Oskari. As these were taken well into the morning, i can see that altitude of both Mars and Jupiter was decently high for you - above 32 degrees!

You obviously have excellent optics in your Newt to be turning in this level of detail from a 10" aperture, and you managed the focusing very well. As you mention, no contrast issues from the condensation on the diagonal, and nicely processed. Bravo!

Thank you! Indeed, taken just before sunrise when the skies were the calmest and the planets had decent elevation. I had been doing deep sky imaging until then so the mirrors were perfectly acclimatized to the ambient temperature as well (had been running a fan all night, turned it off for recording).

22 minutes ago, Kon said:

Nice images Oskari. At this small size Mars and not perfect seeing, I also use Jupiter and tweak it a bit. You may want to add an ADC in the mix. There is one in classifieds UK on good price.

Thanks, ADC might be too much trouble for now. My best Jupiter with the 8'' was a fair bit sharper than this and also sans ADC, so i think i'll do without for now as there is plenty of room to improve with the 10'' still. Also not looking forward to the headache of figuring out the angle to set it to with an EQ mounted newtonian and a horizon at an odd angle. One day will have to get one, but not right now.

[geeklee]

Superb images Oskari - Jupiter especially - nice one!

[CraigT82]

Those are both really nice images, good work! Both planets show a bit of an edge rind. I find you can mitigate that quite well by using a circular selection tool to select around the edge of the disc, shrink the selection so it’s about 15pixels in wards from the edge of the disc, invert selection and then apply a bit of Gaussian blur. 

[ONIKKINEN]

20 minutes ago, CraigT82 said:

Those are both really nice images, good work! Both planets show a bit of an edge rind. I find you can mitigate that quite well by using a circular selection tool to select around the edge of the disc, shrink the selection so it’s about 15pixels in wards from the edge of the disc, invert selection and then apply a bit of Gaussian blur. 

Thanks, this trick is going straight to my toolbox for sure.

 

[Space Cowboy]

Those are excellent images!

[bosun21]

18 hours ago, CraigT82 said:

Those are both really nice images, good work! Both planets show a bit of an edge rind. I find you can mitigate that quite well by using a circular selection tool to select around the edge of the disc, shrink the selection so it’s about 15pixels in wards from the edge of the disc, invert selection and then apply a bit of Gaussian blur. 

It can also be mitigated by setting the limb darkening/brightening in Winjupos.

Edited Saturday at 15:23 by bosun21

[maw lod qan]

Those are excellent images!

Mars is really amazing for it being so small. 

[vlaiv]

I observed Jupiter last night with 110ED scope and GRS was on display. It looked like it shrunk and had some sort of prominent bright edge - which I thought was strange at that moment.

Came here to verify what I saw and I must say that I'm enjoying the quality of the images very much, besides having verified what I saw last night.

[ONIKKINEN]

4 hours ago, vlaiv said:

I observed Jupiter last night with 110ED scope and GRS was on display. It looked like it shrunk and had some sort of prominent bright edge - which I thought was strange at that moment.

Came here to verify what I saw and I must say that I'm enjoying the quality of the images very much, besides having verified what I saw last night.

It does appear to be shrinking in its "pocket". Just so happens i took an image of Jupiter a year ago with almost the same Jupiter rotation - dated Sept 7th 2023. In this 2023 image there is this bright lip around the GRS, but only in the 12 to 3 o'clock direction. The more recent image shows this bright region all around the GRS. Guessing this contrast between the spot and the surrounding bright material was what you observed?

 

[vlaiv]

2 minutes ago, ONIKKINEN said:

Guessing this contrast between the spot and the surrounding bright material was what you observed?

Yes. Visually it appeared as GRS is smaller in size and "detached" from the rest of the features on SEB

Actually, when I reduce the size of your image - I get pretty much the same view I had with ~4mm eyepiece at 660mm of FL with 110mm of aperture:

[ONIKKINEN]

2 minutes ago, vlaiv said:

Yes. Visually it appeared as GRS is smaller in size and "detached" from the rest of the features on SEB

Actually, when I reduce the size of your image - I get pretty much the same view I had with ~4mm eyepiece at 660mm of FL with 110mm of aperture:

It does pop out from this example. Its been a year since i last observed the GRS through an eyepiece, will check visually next time for sure. I'm thinking of converting my 8'' back to visual use since now the 10'' does all the imaging work, although a sane person would probably do it the other way around.

[morimarty]

They are a cracking pair of images. You have processed them with a lovely natural look,