Jupiter - First Time Stacking a Planet

[Mandy D]

OK, I know the image is small, but I was working at native focal length and imaging with a D800, so only got 60 pixels across Jupiter. I suspect, from what I've read in here, that I need to barlow my scope to about 4000 mm FL with this camera. I was working with the 200P last night and this is my first stack of 40 still images of Jupiter combined with a single exposure for the Gallilean moons, Ganymede, Io, Callisto and Europa from left to right.

Hopefully, with a little (a lot of?) help from you good people in here, I can improve greatly on this result in the future, but I'm happy with it as a first attempt.

[DaveL59]

I'd have been very happy to end up with an image like that one, maybe one day I'll try hooking the dslr up to the TAL100RS, just haven't felt the motivation to do that so far and just enjoying the views instead 🙂 

[Mandy D]

3 minutes ago, DaveL59 said:

I'd have been very happy to end up with an image like that one, maybe one day I'll try hooking the dslr up to the TAL100RS, just haven't felt the motivation to do that so far and just enjoying the views instead 🙂 

Thank you, that really means a lot to me!

I've just stacked 50% of my second run for a total of 190 frames out of 381 taken in 3 minutes. I think it is a tiny bit better.

[Laurieast]

Well done you! Progress! 😀

Yes, the second one dose have the edge over the first one.

[Mandy D]

1 hour ago, Laurieast said:

Well done you! Progress! 😀

Yes, the second one dose have the edge over the first one.

Thank you. Do you think it needs to be brighter?

[Laurieast]

18 minutes ago, Mandy D said:

Do you think it needs to be brighter?

Yes, a little, try with curves adjustment. 

With your second image imposed on top of the one with the moon's.

maybe a bit bright 🤔

Edited August 28, 2022 by Laurieast

[Mandy D]

5 hours ago, Laurieast said:

Yes, a little, try with curves adjustment. 

With your second image imposed on top of the one with the moon's.

maybe a bit bright 🤔

Thank you, that looks a lot better. So my next problem is to increase the image size and, from what vlaiv has said elsewhere the limit for my 200P with 1200mm focal length and a D800 camera is about 3.3x. I am considering an Explore Scientific focal extender at 3x, here, https://www.rothervalleyoptics.co.uk/explore-scientific-focal-extender-3x-508mm2.html. I want to go with 2" to better match my full frame sensor so I can image stuff other than planets. Is this one a good option? Will it be OK with both the 200P and the RC6? I guess it might be a bit much with the RC6, but I do have a reducer / field flattener for it. Can I use both together.

Sorry for so many questions.

Edited August 28, 2022 by Mandy D

[Laurieast]

Questions are good! 

I would be guessing if I answered that, I have never used one. I have a cheap 1.25" 2x Celestron barlow, a 1.25" 3x SV Bony barlow, which is good, but with your sensor maybe not, and a 2" 2x ED barlow https://www.firstlightoptics.com/barlow-eyepieces/skywatcher-ed-deluxe-2x-two-inch-barlow-lens.html

There is an informative thread here about focal extenders: https://www.cloudynights.com/topic/665643-difference-between-focal-extender-and-barlow/

It looks as though it gives a flatter field, but if it would work with your kit 🤔 , it would be good if @vlaiv saw this and may have some better answers.

 

[vlaiv]

9 hours ago, Mandy D said:

Thank you, that looks a lot better. So my next problem is to increase the image size and, from what vlaiv has said elsewhere the limit for my 200P with 1200mm focal length and a D800 camera is about 3.3x. I am considering an Explore Scientific focal extender at 3x, here, https://www.rothervalleyoptics.co.uk/explore-scientific-focal-extender-3x-508mm2.html. I want to go with 2" to better match my full frame sensor so I can image stuff other than planets. Is this one a good option? Will it be OK with both the 200P and the RC6? I guess it might be a bit much with the RC6, but I do have a reducer / field flattener for it. Can I use both together.

Sorry for so many questions.

If you really want to use D800 for planets, then based on pixel size which is 4.88, you'll need F/19.52, so yes, x3.25 is needed.

However, I think that it would be better to invest in planetary camera rather than focal extender for D800.

I would also advise against using focal extender for both 200p and RC6 for DSO imaging. Both scopes have enough focal length and don't need one.

For last question - don't use field flattener/reducer with barlow / focal extender. Not much point in doing so - you first reduce focal length only to extend it. If you just use field flattener and barlow / focal extender - it is also not necessary. Field flattener is often needed for outer part of the field - central 1/2 of the field does not need it.

With barlow, you magnify image and you just take central part of image (1/2 or less of it) and you spread it over whole sensor. That part of the image does not need flattening anyway.

[Mandy D]

3 hours ago, vlaiv said:

If you really want to use D800 for planets, then based on pixel size which is 4.88, you'll need F/19.52, so yes, x3.25 is needed.

However, I think that it would be better to invest in planetary camera rather than focal extender for D800.

I would also advise against using focal extender for both 200p and RC6 for DSO imaging. Both scopes have enough focal length and don't need one.

For last question - don't use field flattener/reducer with barlow / focal extender. Not much point in doing so - you first reduce focal length only to extend it. If you just use field flattener and barlow / focal extender - it is also not necessary. Field flattener is often needed for outer part of the field - central 1/2 of the field does not need it.

With barlow, you magnify image and you just take central part of image (1/2 or less of it) and you spread it over whole sensor. That part of the image does not need flattening anyway.

Thank you of the input. It is greatly valued.

I already have a ZWO ASI178MM (2.4 micron pixel size), which could be used as a planetary camera, albeit mono. With 2x2 binning, the 3x focal extender would be a good match if I have my numbers right, so I could use it with both the D800 and the ZWO. Would this potentially be a good starting point? If I get on with it, I could then buy the colour version or filter wheel, although I'd prefer one-shot for planetary.

Right now, I really need to stick with the DSLRs for my imaging as I am out of action for driving and don't want to set up a full imaging train with laptop next to the pavement outside home. Later, when my eye is better I will be able to throw all the kit in the Land Rover and head for dark skies where I can set up properly.

So, I am thinking that the 3x would be a sensible investment now as it would work for both the D800 and the ZWO.

I take on board your advice to not use the flattener with the extender.

So, I have the 200P which is working great for planetary. Would the RC6 offer any advantage over it? Obviously, I would lose aperture, so I would not be able to go the the same focal long lengths for either camera. I also assume, from your comments regarding flatness over the small area of field required for planetary, that I would not gain anything here, either, with or without the flattener.

Edited August 29, 2022 by Mandy D

[Mandy D]

3 hours ago, Laurieast said:

Questions are good! 

I would be guessing if I answered that, I have never used one. I have a cheap 1.25" 2x Celestron barlow, a 1.25" 3x SV Bony barlow, which is good, but with your sensor maybe not, and a 2" 2x ED barlow https://www.firstlightoptics.com/barlow-eyepieces/skywatcher-ed-deluxe-2x-two-inch-barlow-lens.html

There is an informative thread here about focal extenders: https://www.cloudynights.com/topic/665643-difference-between-focal-extender-and-barlow/

It looks as though it gives a flatter field, but if it would work with your kit 🤔 , it would be good if @vlaiv saw this and may have some better answers.

 

Thanks for your response. Great job on brightening my Jupiter image. It does look improved.

I've had a read through the Cloudy Nights thread and found some helpful information. I just need to firm up my ideas, now.

[vlaiv]

4 minutes ago, Mandy D said:

Thank you of the input. It is greatly valued.

I already have a ZWO ASI178MM (2.4 micron pixel size), which could be used as a planetary camera, albeit mono. With 2x2 binning, the 3x focal extender would be a good match if I have my numbers right, so I could use it with both the D800 and the ZWO. Would this potentially be a good starting point? If I get on with it, I could then buy the colour version or filter wheel, although I'd prefer one-shot for planetary.

Right now, I really need to stick with the DSLRs for my imaging as I am out of action for driving and don't want to set up a full imaging train with laptop next to the pavement outside home. Later, when my eye is better I will be able to throw all the kit in the Land Rover and head for dark skies where I can set up properly.

So, I am thinking that the 3x would be a sensible investment now as it would work for both the D800 and the ZWO.

I take on board your advice to not use the flattener with the extender.

So, I have the 200P which is working great for planetary. Would the RC6 offer any advantage over it? Obviously, I would lose aperture, so I would not be able to go the the same focal long lengths for either camera. I also assume, from your comments regarding flatness over the small area of field required for planetary, that I would not gain anything here, either, with or without the flattener.

Main reason to go for planetary with dedicated camera is ability to take large number of exposures in sequence (frames) - in Raw format.

If you already have ASI178 - then I'd try with that first - just to hone your technique.

For planetary imaging - you don't need to drive to dark location - you can do it from your back yard. Light pollution is not an issue there.

It would be best to get regular barlow for that. You don't want to bin data if you don't need to - as that increases effective read noise with CMOS sensors. For planetary imaging - low read noise is essential.

Both of your scopes will have diffraction limited field over such a small sensor and you don't need any additional optics, but I would avoid using RC for planetary.

It has very large central obstruction, and although, one can image planets with it - results won't be as good as scopes with smaller central obstruction (even SCTs).

Anyway, for ASI178 you'd need ~F/10 scope. Get this barlow:

https://www.firstlightoptics.com/barlows/astro-essentials-125-2x-barlow-with-t-thread.html

It has detachable barlow element that you can use to dial in magnification for your 200p.

Magnification of barlow element depends on distance to sensor and you can use some sort of variable length extension to attach it directly to camera body via T2 and then use 2" camera nose piece to fit it inside focuser. This way you can dial in magnification to get F/10

 

[Mandy D]

4 hours ago, vlaiv said:

Main reason to go for planetary with dedicated camera is ability to take large number of exposures in sequence (frames) - in Raw format.

If you already have ASI178 - then I'd try with that first - just to hone your technique.

For planetary imaging - you don't need to drive to dark location - you can do it from your back yard. Light pollution is not an issue there.

It would be best to get regular barlow for that. You don't want to bin data if you don't need to - as that increases effective read noise with CMOS sensors. For planetary imaging - low read noise is essential.

Both of your scopes will have diffraction limited field over such a small sensor and you don't need any additional optics, but I would avoid using RC for planetary.

It has very large central obstruction, and although, one can image planets with it - results won't be as good as scopes with smaller central obstruction (even SCTs).

Anyway, for ASI178 you'd need ~F/10 scope. Get this barlow:

https://www.firstlightoptics.com/barlows/astro-essentials-125-2x-barlow-with-t-thread.html

It has detachable barlow element that you can use to dial in magnification for your 200p.

Magnification of barlow element depends on distance to sensor and you can use some sort of variable length extension to attach it directly to camera body via T2 and then use 2" camera nose piece to fit it inside focuser. This way you can dial in magnification to get F/10

 

Yes, this looks like a pl... (the first part of a plan!).

I didn't mean that I need astro-dark skies for my planetary imaging, I just need to get away from the uber-bright LED streetlights for the sake of my eyes. I have no chance when pointing due south of avoiding being blinded. From my garden, I have a very narrow window to the south which allows me a few minutes on the Moon or planets per night, then another narrow window to the west, so no chance of doing any serious planetary imaging from my own property. However, I do have a couple of sites away from home with no street lighting and clear views of the south and west horizons that I like to use. I really do not want to set up a laptop next to my scope on the pavement. Hence, my preference to stick to DSLR imaging at this point in my life. I am sure you understand that I am not rejecting your very good advice, but simply putting it into perspective for my situation.

I have a an inexpensive 2x Barlow already, so will give that another try and see where we get once I have some clear skies, again. That still leaves me wanting for a 3x Barlow for the DSLR and 200P, but that can wait for now. I'll leave the RC for this endeavour and keep persevering with the 200P. It seems to give reasonable results, anyway.

What camera do you recommend I consider for planetary? I'd like to stick with ZWO if possible and am not yet ready to buy, but it will help me budget.

Thanks again.

 

[vlaiv]

3 hours ago, Mandy D said:

That still leaves me wanting for a 3x Barlow for the DSLR and 200P, but that can wait for now.

Why do you want that?

3 hours ago, Mandy D said:

What camera do you recommend I consider for planetary? I'd like to stick with ZWO if possible and am not yet ready to buy, but it will help me budget.

You seem to have ASI178mm.

Use that to practice and to see what is possible with your scope. You already have barlow that you can use with that camera. Just aim to get a bit below x2 and that should work fine. Much better than with DSLR.

Aim for 5ms exposure length, use 640x480 roi, capture as many subs as you can. Use gain in 260-300 range.

As far as recommended OSC for planetary imaging - go with ASI224 or ASI385 - depending on how much money you are willing to spend and if you need larger sensor (ASI385 is larger sensor which is useful for moon). Although, for moon, you can simply use ASI178. It is largest and you can capture lunar images in mono, so you don't even need filters for that (or you can just use green or red filter to help with seeing a bit).

 

[Mandy D]

2 hours ago, vlaiv said:

Why do you want that?

You seem to have ASI178mm.

Use that to practice and to see what is possible with your scope. You already have barlow that you can use with that camera. Just aim to get a bit below x2 and that should work fine. Much better than with DSLR.

Aim for 5ms exposure length, use 640x480 roi, capture as many subs as you can. Use gain in 260-300 range.

As far as recommended OSC for planetary imaging - go with ASI224 or ASI385 - depending on how much money you are willing to spend and if you need larger sensor (ASI385 is larger sensor which is useful for moon). Although, for moon, you can simply use ASI178. It is largest and you can capture lunar images in mono, so you don't even need filters for that (or you can just use green or red filter to help with seeing a bit).

 

Yes, I have ASI178MM. I've just set it up in my living room with a 30 mm lens and focussed it on the ceiling as totally clouded over here tonight. I've set gain to 280 and exposure at 5 ms. At 640 x 480 the detail on my ceiling is unreal. You can see the brush marks in the paint with the camera on the floor!

Should I be running the camera at 8 bit or 16 bit for planetary?

I guess that videos should be two to three minutes long each, from what I have read because of fast rotation of Jupiter.

As you suggest, for now I will practice with the ASI178MM, but look towards getting a colour camera later. I am quite happy to spend up to about £500 on a new camera, so the ASI385 is comfortably within reach. Is there any point in spending more within my budget?

I did explain my logic behind the 3x focal extender previously as a stop gap for use with my DSLR until I can get my full imaging rig to a location where I can safely set up with a laptop and everything I need. With currently being unable to drive, I am stuck at home and imaging from the street. I have to carry everything out in one go as I can leave nothing outside to go back in for the rest.

Thanks.

 

[Mandy D]

I found a better set of moons for Jupiter and re-processed the planet in GIMP. Is this getting better?

[Laurieast]

Much better. 

Does GIMP have this, or similar? 

Select/Inverse, darken the background a little (levels), I can see your pasting or masking.

 

Edited August 30, 2022 by Laurieast

[DaveL59]

defo a step up, the moons look much better focused in this one 🙂 

[Mandy D]

1 hour ago, DaveL59 said:

defo a step up, the moons look much better focused in this one 🙂 

Yes, they do, don't they? However, it was not a telescope focussing issue; it was more of a prime weed issue with the occasional cloud of smoke passing in front of the telescope from a neighbouring flat. I didn't touch focus throughout most of my imaging time, after the scope had cooled. First attempt, I rushed to find some good moons, but had 700 images to go through! Many of them had figure 6 shaped tails, due to the smoke.

[Mandy D]

1 hour ago, Laurieast said:

Much better. 

Does GIMP have this, or similar? 

 

Select/Inverse, darken the background a little (levels), I can see your pasting or masking.

 

 

I will check later, thanks. Having blindness in one eye issues at present, which does not help focus and contrast in other eye.

[vlaiv]

1 hour ago, Mandy D said:

I found a better set of moons for Jupiter and re-processed the planet in GIMP. Is this getting better?

Don't be afraid to add brightness to the image (and control background with contrast).

Here is what can be quickly done in IrfanView (it has very basic set of color correction options):

[DaveL59]

9 minutes ago, Mandy D said:

Yes, they do, don't they? However, it was not a telescope focussing issue; it was more of a prime weed issue with the occasional cloud of smoke passing in front of the telescope from a neighbouring flat. I didn't touch focus throughout most of my imaging time, after the scope had cooled. First attempt, I rushed to find some good moons, but had 700 images to go through! Many of them had figure 6 shaped tails, due to the smoke.

so I guess your "seeing" got a bit out of focus by the end too then 😉 

Edited August 30, 2022 by DaveL59

[Mandy D]

18 hours ago, DaveL59 said:

so I guess your "seeing" got a bit out of focus by the end too then 😉 

Nope! Thankfully the smoke was going out and upwards and I was down on the ground. 🙂

[Mandy D]

On 30/08/2022 at 19:01, vlaiv said:

Don't be afraid to add brightness to the image (and control background with contrast).

Here is what can be quickly done in IrfanView (it has very basic set of color correction options):

That is pretty amazing, considering how small an image I got and how little detail was in each frame. Last night was a complete washout, as I was 2 hours earlier and the sky was pretty terrible. The moons kept popping in and out of view and I was seriously struggling to achieve focus. This was the best from last night with the D3200 and a 2x barlow on the 200P. I might see if I can find a clear night Friday or Saturday when I can stay up much later and see what I can get.