Help me up my planetary imaging game

[PeterC65]

13 hours ago, imakebeer said:

Thanks for the offer, much appreciated 👍🙏 These are the 3 Jupiter logs from Sharpcap (Mars wasn't much different). Mainly I was just playing around with gain and exposure to vary the histogram between about 40-60% (or maybe 30-70%).

My method for imaging the Moon and planets is to set the gain to just above the HCG / LCG switching point, then gradually reduce the exposure until the image is just below the over-exposed point. In SharpCap you can set an FX to highlight (in red) areas of the image that are over exposed so I just reduce the exposure (by pressing the F1 key) until all of the red areas just disappear.

 

[PeterCPC]

13 hours ago, imakebeer said:

Couldn't resist also sharing this Mars image - was too ashamed of the poor quality to share them before but just gone through the post-processing again and was rather pleased and surprised when this popped out from Registax. Still not amazing but probably my best Mars image yet, much better than my previous orange/brown blobs! 😊

That's not too shabby. It's as good as my last effort. Keep going.

[inFINNity Deck]

22 minutes ago, PeterC65 said:

I don't have an ADC so can't comment on their usage or effectiveness.

ADCs are very effective and a must have for obtaining good planetary images, even if imaging is done using a monochrome camera. The filters (whether they are embedded as a Bayer-pattern, or sit in a filter-wheel) have a band-width of about 100nm per colour. Suppose we image a planet at 40 degrees altitude, then the light coming in through a blue filter (400-500nm) disperses by about 0.7 arc-seconds, green light (500-600nm) disperses by about 0.4", and red by about 0.2". The PDS150 at f/15, combined with the GPCAM3, will image at about 0.3"/pixel, so in blue the refraction induced smearing is more than 2 pixels, in green this is more than 1 pixel and in red almost 1 pixel.

Using an ADC this can be reduced to virtually zero. When we do nothing at all in the processing, the smearing from blue towards red is at least 1.3 arc-seconds  or 4 pixels (actually more like 1.5 arc-seconds or 5 pixels as blue starts around 380-390nm). When the object is lower the refraction increases significantly, at 20 degrees altitude the total smearing is more than 3 arc-seconds (some 10-11 pixels).

Nicolàs

[imakebeer]

1 hour ago, PeterC65 said:

Yes you are using the prime focus method. The magnification you get from a Barlow varies quite a bit depending on the distance between the Barlow lens and the camera sensor.

Yeah, this is something I'd been wondering. When I was imaging Mars I did actually try moving the Barlow relative to the focuser tube, and also the camera relative to the Barlow - it certainly wasn't exhaustive but I couldn't find a sharper or much bigger image (yet!). I will kepp experimenting, including with the 2x & 3x Barlows 👍

1 hour ago, PeterC65 said:

I use SharpCap but don't know what you mean by BYN/BYE?

Haha, BackyardNikon and BackyardEOS - commonly used for capture if you're using a Nikon or Canon. Free trial and thereafter paid for but starting out I found them much more user friendly and intuitive than anything else. I use them for DSO AP as I have a Nikon D5500 & Canon 450D, but the Altair/ZWO planetRY cameras necessitate someting else, hence Sharpcap.

1 hour ago, PeterC65 said:

I'm still refining my post processing method but am currently thinking that DeNoise may do a better job than RegiStax wavelets (yet to be tested).

OK, so might be worth me checking out DeNoise as a possible alternative to Registax - thanks 👍

1 hour ago, PeterCPC said:

That's not too shabby. It's as good as my last effort. Keep going.

Thanks for the encouragement buddy, I will 👍💪😊

 

[johnturley]

1 hour ago, PeterC65 said:

 

I don't have an ADC so can't comment on their usage or effectiveness.

 

 

I don't think that you would notice a massive improvement with an ADC especially on Mars with its current high altitude, and with a 150 mm scope. 

In addition with a Newtonian Reflector, you may not have sufficient in travel to add an ADC to the light path.

I do have a ZWO ADC but have never bothered using when it when imaging, I found last year when Jupiter was quite low down, it improved the visual view through my 14in Newtonian significantly, but not much difference this year.

John  

[PeterC65]

This web page looks like a good summary on ADCs (it is referenced in the SharpCap manual). The with and without images show quite an improvement and the ADC seems to be beneficial for visual as well as camera observing. I do very quickly run out of in focus with the 150PDS but not so much with the 72mm APO. Next time I'm observing Jupiter I will check to see what atmospheric dispersion I am getting.

 

[johnturley]

1 hour ago, PeterC65 said:

This web page looks like a good summary on ADCs (it is referenced in the SharpCap manual). The with and without images show quite an improvement and the ADC seems to be beneficial for visual as well as camera observing. I do very quickly run out of in focus with the 150PDS but not so much with the 72mm APO. Next time I'm observing Jupiter I will check to see what atmospheric dispersion I am getting.

 

Interesting read, in particular it states that :-

'ADCs are designed to work best at high f-ratios. At short f-ratios or with large amounts of prism correction, aberrations can be introduced which can start to offset the overall benefits. To reduce aberrations on short focal ratio scopes it is best that they are placed directly after the Barlow lens and a reasonable distance from the camera. For longer f-ratio scopes, such as SCTs, putting the ADC before the Barlow is less problematic and has some advantages in increasing the available amount of correction for low altitude objects.

I've only tried using my ZWO ADC with my 14in Newtonian at its native focal ratio of f5, maybe I would get better results if I tried using it with a Barlow. There has been a lot of discussion on 'Cloudy Nights' with regard to to the very expensive (£3.5k) Gutekunst ADC's, and they are best used in conjunction with a Barlow.

However the ADC didn't seem to give much improvement with my f7 Esprit 150 either, which incidentally unlike my 14in Newtonian, doesn't usually exhibit much false colour due to atmospheric dispersion, unless the object being viewed is very low down, which is why I thought 'imakebeer' would not notice much improvement with his Skywatcher 150P. 

[Mart29]

On 30/12/2022 at 12:13, imakebeer said:

Sorry, this is a long one, but please bear with me, i'd really appreciate some guidance.

There are two questions here:

1. First, please help me up my planetary imaging game. What is it you guys are doing that I'm not to get (what appear to me to be) large hi-res images of Jupiter & Mars?
2. Second, am I expecting too much from a 5x Barlow?

I did my first serious planetary images in October 2022, starting with a SW Capricorn 900mm/70mm frac on a wobbly EQ1 mount. I used a Nikon D5500 or Canon 450D 
 with an Svbony eyepiece protection adapter and 25mm eyepiece.
 
I used BYN/BYE plus PIPP, AS3! and Registax.

Considering the basic equipment I was pleased with the images I achieved, e.g.

Now I've upgraded though I'm struggling to make any further improvement:

• SW 150PDS - not the weapon of choice for planetary maybe, but should still be an improvement I think.
• HEQ5 - tracking at last, and not wobbly like the EQ1!

But I found I couldn't obtain focus on the PDS with the previous camera setup, i.e. Canon 450D, eyepiece projection adapter and 25mm eyepiece (not enough inward focus travel), but I could with a 2x Barlow. Instead I tried with the kit SW 1.25" 2x Barlow - I could focus but i think maybe this Barlow isn't great optically, it seems to have lots of CA. I noted that the images were pretty much the same size in terms of pixels across the diameter of the planet as previously with the 25mm eyepiece.

I tried again with a different camera - this time an Altair GPCAM3 224C USB3, combined with the same 2x Barlow, but didn't notice any great leap forward in images quality.

I wondered if the trick is to magnify the image more, i.e. spread the image out over more pixels on the sensor to resove more detail? Looking at the "Which Barlow?" section of "Planetary Imaging Tutorials" he recommends (I think based on longer discussions on Cloudy Nights) you want a focal ratio about 5 (or 6 or 7) x pixel size in microns, therefore.....

So with the GPCAM3 (3.75um) I want a FR around 18.75-26.25. The 150PDS is f/5 so a 4x or 5x Barlow seems about right - I went ahead and got an Svbony 5x Barlow (along with a 2x and 3x).

I tried again last night with the 150PDS, Svbony 5x Barlow, GPCAM3 and Sharpcap. I did 3 x 3mins on Jupiter between about 30-70% histogram, and similar again on Mars (about 10-20k frames).

When I processes the resulting AVIs in AS3! I was surprised to find the images weren't much bigger than I'd done previously, and the quality was no better than I've achieved before with much more modest equipment. Cropping out the black space of the imported AVI in AS3! both Jupiter and Mars are still well under 150 x 150 pixels.

So am I expecting too much from a 5x Barlow? Should I not expect it to give me an image roughly twice the size of a 2x Barlow (albeit dimmer perhaps)? (Test vids on some trees a few hundred metres away at least confirmed it gives this kind of gain at short range at least!)

Am I missing something about the image capturing/post-processing? I'd swear others are posting bigger / hi-res / more pixel images. How do you get this extra level of detail? Surely not everyone is using a 500mm+ light bucket to image planets?

Is it the equipment, be it the scope, mount, camera, Barlows etc? Is it capture, i.e. do I need many more frames? Am I driving the software wrongly, Sharpcap, AS3!, Registax? Is there something more I need to do in GIMP for example?

Thanks if you've read this far - I'd really appreciate some guidance.

Cheers! 👍🔭🙏

Hello, I can't really answer on the tech side as I only get shots on my mobile phone . But, as said seeing conditions is everything!

×5 barlow seems alot to me , x2 or x3 for Jupiter and Mars should be plenty! 

Attached are Jupiter and Mars with just my phone camera held to the eyepiece, a 11mm DeLite through a x2 barlow.   

It could also be down to settings on your DSLR . 

The images below are 5 sec videos and manual selection of an image, no stacking or software used . 

I like your second Jupiter image  😀  

I don't like the process of imaging and enjoy the eyepiece and a quick phone video,  which on good seeing gets good details on Jupiter and Mars. 

Some of the high res images on here are mind blowing but they have come with lots of experience and skill! 

The guys have great scope set ups and skill with them and a great knowledge of processing the images,  it's to much for me to get into as I enjoy the eyepiece to much but hats off to them for makings stunning images to enjoy!

these guys will show you everything you need 🙃

 

Edited December 31, 2022 by Mart29

[johnturley]

Thought I would post some images of Mars, showing a similar area of the planet taken through different scopes, and different techniques to show the different image sizes obtained.

The first image is of Mars taken on 12-13/11/2022 through my Esprit 150 and ZWO ASI 462 Planetary Camera using a 2.5 x Powermate (effective focal length 2,650 mm) giving f17.5

The second image was taken about 30 minutes later through my 14in f5 Newtonian with the same setup (effective focal length 4,500 mm) giving f12.5.

The third image was taken in September 2020 (before I obtained my planetary camera) through my 14in f5 Newtonian, and Canon 6D digital SLR using eyepiece with a  9.7 mm Plossl eyepiece.

The images were processed using AutoStakkert and/or Registax with a bit of polishing in Lightroom

Note the superiority of the ZWO Planetary Camera over the digital SLR.

I am also a relative beginner to planetary imaging, and my results are nowhere near as good as those of Neil Philips or Geoff Lewis, I would have thought that with imakebeer's Skywatcher 150P it should be possible to get results nearly as good as those with the Esprit 150. 

 

 

 

 

 

Edited December 31, 2022 by johnturley

[inFINNity Deck]

5 hours ago, johnturley said:

Interesting read, in particular it states that :-

'ADCs are designed to work best at high f-ratios. At short f-ratios or with large amounts of prism correction, aberrations can be introduced which can start to offset the overall benefits. To reduce aberrations on short focal ratio scopes it is best that they are placed directly after the Barlow lens and a reasonable distance from the camera. For longer f-ratio scopes, such as SCTs, putting the ADC before the Barlow is less problematic and has some advantages in increasing the available amount of correction for low altitude objects.

I've only tried using my ZWO ADC with my 14in Newtonian at its native focal ratio of f5, maybe I would get better results if I tried using it with a Barlow. There has been a lot of discussion on 'Cloudy Nights' with regard to to the very expensive (£3.5k) Gutekunst ADC's, and they are best used in conjunction with a Barlow.

However the ADC didn't seem to give much improvement with my f7 Esprit 150 either, which incidentally unlike my 14in Newtonian, doesn't usually exhibit much false colour due to atmospheric dispersion, unless the object being viewed is very low down, which is why I thought 'imakebeer' would not notice much improvement with his Skywatcher 150P. 

Part II of that page is especially of interest as it explains in great detail the aberrations you can expect (it is link to at the bottom of Part I).

Nicolàs

[Nigella Bryant]

I think in the UK seeing is the issue, only a very few time's are there time's when it's exceptionally good for high resolution planetary imaging. I use a 2.5x powermate for Jupiter and a 3x Barlow for Mars on my C11 with a Zwo camera. Take the image's when the planet is highest in the sky and still use an ADC. I've only just begun myself and still having failure after failure, seeing related. I try to get the highest frame rate possible. 2 mins for Jupiter and 3mins for Mars. 

Attached is my very best so far this season. 

Edited December 31, 2022 by Nigella Bryant
Images added

[inFINNity Deck]

Nice images Nigella!

I think it is good for Beermaker and other planetary starters to know that most quality images we get presented are the result of many failures. It takes quite a few attempts before a good image is taken. A few tips:

- Always use an ADC (unless imaging near zenith);
- Always check collimation on a nearby star (unless imaging with a reflector);
- Always focus (some do it visually on the planet itself, but I learned the hard way that using a Bahtinov-mask on a nearby star or planetary moon works easier and better);
- Always take multiple runs (seeing can change in a matter of minutes);
- Do not expect every imaging session to result in a good image.

Here is how I started four years ago (C11, 2x PowerMate, ZWO ASI174MM):

 

And this is now, still using the same equipment:

 

Still I have plenty recent examples that look nothing like this and that is what seeing does to your project...

Nicolàs

 

[imakebeer]

Thanks again everyone for the advice, I have some updates with a couple of images below.

I spent some time playing during the day earlier this week, comparing different combinations of no Barlow / 2x / 5x and the ZWO ASI120 vs Altair 224 (3x Barlow arrived in the post today!).

Initially the ZWO seemed to give a more pronounced difference between the 2x & 5x Barlows.

One important thing I figured out, which @PeterC65 alluded to, is each camera has a different distance from the extension tube to the samera. The Altair has an extra 20mm-ish extension tube you can screw on, but I think even this isn't enough so I need to push it not all the way in to the Barlow.

Later that evening (2nd Jan) I had a few clear hours after sunset to try with Jupiter and Mars. Not ideal doing it from the back garden at it meant Jupiter was just over the roof of the house - I could go out the front but then I have to contend with streetlights!

I took way more video (at various different gains and exposure times) than I've yet had time to process but I did the ZWO + 2x Barlow and the Altair + 5x Barlow. The latter seemed better overall.

I'll also add that the Altair + 5x Barlow combo (with the camera not pushed fully in!) now seems to give me an image size of Jupiter about 150px across which is more or less what Stellarium predicts in its FOV tool.

I had a go at using the tools in PIPP to select the best quality frames but it didn't seem to add any benefit. I've also had a go with Winjupos but so far it's only outputting my colour videos in black & white (anyone know why?).

So for now it's just trusty old AS3! + Registax. I've had a few goes and the images below are probably the best I've done yet for either planet.

In particular I'm interested to try and relate the patterns on Mars to a map but I've not figured it out yet (1954hrs on 2nd Jan 2023 if anyone can tell me)

Jupiter (no drizzle)

Mars (3x drizzle)

Edited January 5, 2023 by imakebeer
Tagging other user

[wesdon1]

On 30/12/2022 at 15:59, inFINNity Deck said:

Hi Beermaker,

maybe it is good to read a bit more about the limitations of planetary imaging. There are some threads that discuss it in parts in this forum, but I have written two articles about it in a Dutch forum (they should translate properly when opened in Chrome).

In short: the optimal focal ratio is around 3.7 x [pixel size], but that is not including the effect of seeing. Seeing ignored, for your GPCAM3 it will be 3.75 x 3.7 = f/13.9. So although under perfect conditions a 3x Barlow should be more than enough, you will not achieve optimal sampling due to seeing. Seeing negatively affects the optimal focal ratio. Your scope is diffraction limited (in green light) at a seeing of about 0.7". If the best seeing (expressed in arc-seconds) is worse than that, the factor 3.7 no longer gives the optimum focal ratio, and should be divided through roughly 1.6 x [seeing] ^ 0.74. So suppose your best seeing was about 1.5", the optimal focal ratio would be 3.75 x 3.7 / (1.6 x 1.5^0.74) = f/6.4! Not that I recommend doing this, as there is always a chance that the best seeing was better than the limit for your scope. It is merely to show that a 5x Barlow is not producing any better image, while it comes at a cost: longer exposure-times (= more smearing) and/or higher gain (= more noise).

If you want a larger image, then it is best to image the planet at a maximum focal-ratio of 3.7 x [pixel size], stack the result and then resize it using your favourite photo-processing software.

A good example is this post (again in Dutch, but again Chrome translates): https://www.starry-night.nl/forums/topic/mars-op-26-december-2022/

It shows Mars imaged with two cameras (ZWO ASI174MM and ASI290MM) in the same night, the former camera having pixels twice the size of the latter. Both were recorded at f/20. The larger-pixel camera does, however, show the same detail as the smaller-pixel camera, simply because the latter was oversampling by a factor of 2 (seeing not included).

HTH

Nicolàs

 

Hi again @imakebeer, I know I'm green around the gills at planetary imaging still, but in laymen's terms, I think I have a way of describing this formula(s). Basically, you know how when we started out with telescopes, doing visual, and we mistakenly believed that simply cranking up the EP power/mags would give us better views of planets, and we quickly learned that there's a sweet spot, whereby any more increase in mags just blurrs the views, basically magnifying all the atmospheric distortions of what we were looking at, and REDUCING RESOLUTION. And we learned that we had to limit our mags based on the seeing conditions for that particular night? So generally speaking, the above formulas are obviously correct, but it is down to individual people to gauge the seeing for themselves, for their particular local seeing, and make necessary adjustments, each particular night of imaging?

I hope what i'm saying doesn't make me look stupid, it's just what I have taken away from reading this awesomely informative post! And on that subject, I would like to just say a massive thanks @imakebeer and all the contributors, because this actual post is EXACTLY what I have wanted to ask for weeks, but wasn't sure how to ask it!? LOL. So thanks again, especially @imakebeer ! You're practically in the same stage of imaging as myself, and you seem to keep asking about and discussing everything I am currently wanting to learn about! Ace! 

[IDM]

On 05/01/2023 at 22:10, imakebeer said:

Thanks again everyone for the advice, I have some updates with a couple of images below

As another beginner I am finding this discussion really useful. Your last pictures are better than I am yet to achieve on Jupiter. I am inter To know what your frame rate was on the most recent photos? My understanding is that the shorter the exposure then you are more likely to freeze the seeing and be able to select the best frames to stack. I have been using up to 200fps with my zwo asi224mc but still cannot get really good stacked photos.

 

[imakebeer]

10 hours ago, IDM said:

As another beginner I am finding this discussion really useful. Your last pictures are better than I am yet to achieve on Jupiter. I am inter To know what your frame rate was on the most recent photos? My understanding is that the shorter the exposure then you are more likely to freeze the seeing and be able to select the best frames to stack. I have been using up to 200fps with my zwo asi224mc but still cannot get really good stacked photos.

 

Hard to say as I'm still figuring out what settings work best for me but I'm typically playing around in Sharpcap with exposures around 1/60 or 1/125, I think (from memory), plus doing different combinations of exposure and gain.

But mostly I'm looking at the histogram and going for something between approximately 30-70%.

It might be that I need to crank up the frame rate and use more gain, but as I say, I'm still figuring this out.

[bosun21]

Hi all @PeterC65 this was my first capture that I actually tried to do a bit of processing with. Boy that processing is a complicated business for sure. Gimp, Siri, Pixins, Photoshop etc. I just copied the steps of someone on a YouTube video. Got to learn someway. I am beginning to lean towards AP but still enjoy EEVA. The color is a little off I think, but I was still chuffed.

 

[inFINNity Deck]

Processing should not be complicated at all. What I do is as follows:

- Record LRGB data (I image in mono) with FiraCapture at a as short possible exposure time and as high possible frame-rate. Usually I set my gain at somewhere between 250 and 300 and histogram filled to at least 40%.

- Stack with AutoStakkert! using only (but all) those frames that raise above the 50% quality index. Enable sharpening and set Raw Blend to 30% for the ASI174MM, 0% for the ASI290MM.

- sometimes I use WinJupos, but not always, in which case I do the following step:

- RGB-combine in PaintShop Pro and adding the L-data as luminance layer (which is then merged).

- Slight colour correction to ensure the background is black (not red as in above Jupiter). Usually this means I have to lower green by about 5-10%.

- Add a little bit of saturation.

(sometimes I reduce noise using Topaz).

Done. This is how above images where processed.

So no wavelets, no sharpening other than what AS! does, no complicated stuff as IMHO every additional processing step will add artefacts and render the planet into an artificial looking marble. Main importance are collimation, focus, and seeing.

Nicolàs

 

[imakebeer]

Thanks for that @inFINNity Deck, I will try processing my video using similar steps.

Main differences for me are I'm capturing in colour, I use GIMP and don't have Topaz yet. I'll be interested to try those settings in AS3! though.

1 hour ago, inFINNity Deck said:

as short possible exposure time and as high possible frame-rate.

Aren't they the same thing, or at least different sides of the same coin? I.e. exposure time = 1 / Frame rate???

From my limited experience in Sharpcap so far (assume Fire Capture will do pretty much the same thing) I could set the exposure time much lower, but then I'd have to crank up the gain...

Maybe I'm wrong but in my simple brain I'm thinking of gain as an analogue to ISO, so more gain => more noise???

There also seems to be a relationship between gain and frame rate, or at least write speed to the HDD over USB3, but u haven't que figured it out yet 🤔

[inFINNity Deck]

14 minutes ago, imakebeer said:

Thanks for that @inFINNity Deck, I will try processing my video using similar steps.

Main differences for me are I'm capturing in colour, I use GIMP and don't have Topaz yet. I'll be interested to try those settings in AS3! though.

 

Aren't they the same thing, or at least different sides of the same coin? I.e. exposure time = 1 / Frame rate???

From my limited experience in Sharpcap so far (assume Fire Capture will do pretty much the same thing) I could set the exposure time much lower, but then I'd have to crank up the gain...

Maybe I'm wrong but in my simple brain I'm thinking of gain as an analogue to ISO, so more gain => more noise???

There also seems to be a relationship between gain and frame rate, or at least write speed to the HDD over USB3, but u haven't que figured it out yet 🤔

Higher gain indeed results in more noise, which in turn can be reduced by stacking more images (if available).

There is some correlation between Exposure time and frame rate, but at very low exposure times frame rate mainly depends on data speed and ROI size. So going from 5ms to 3ms may increase the frame rate, but most likely it will remain the same (it does limit to about 200fps on my set-up.

Nicolàs

[PeterC65]

2 hours ago, imakebeer said:

Main differences for me are I'm capturing in colour, I use GIMP and don't have Topaz yet. I'll be interested to try those settings in AS3! though.

I've tried GIMP but found that Affinity Photo is better. It feels much more intuitive (important since these tools are complex) and it will run PhotoShop plugins. I paid £36 for a perpetual licence for Affinity Photo. There is no way I would pay £20 per month for PhotoShop.

Topaz Labs let you install and try out the full features of their tools for free, but they watermark everything you save. I tried out all of their tools and found DeNoise AI to be the most effective. Despite its name, it is good for sharpening up images (I use the Low Light Model with Remove Noise set to zero and Enhance Sharpness set to 100). Their Sharpen AI tool seemed to me to be much too aggressive. The Gigapixel AI tool doesn't seem to have memory management (the other two do) and so with larger images it regularly crashes.