Are Amateur Adaptive Optics worth it?

[kingsbishop]

Hello I searched up amateur adaptive optics and I found some on Thorlabs and I am wondering if it is worth it will I be able to reach the diffraction limit with amateur adaptive optics or are they no good and don’t improve seeing?

[DaveS]

You won't find true adaptive optics for amateur level telescopes, at least not yet.

The units sold as "adaptive optics" are more like "active optics" that can take out first order errors caused by gross star movements, but won't correct for wavefront errors as the professional equipment found on big telescopes, which also need laser generated artificial "guide stars" as a reference.

There have been threads in the Imaging section, which basically say that they are only of use for matching flexure in tandem telescopes.

[kingsbishop]

On 22/11/2022 at 01:18, DaveS said:

You won't find true adaptive optics for amateur level telescopes, at least not yet.

The units sold as "adaptive optics" are more like "active optics" that can take out first order errors caused by gross star movements, but won't correct for wavefront errors as the professional equipment found on big telescopes, which also need laser generated artificial "guide stars" as a reference.

There have been threads in the Imaging section, which basically say that they are only of use for matching flexure in tandem telescopes.

I’m talking for planetary and double stars.

[DaveS]

Oh well, you didn't make that clear in your original post.

For planetary or double stars the normal route is lucky imaging to dodge the seeing.

As a DSO imager it's not really my field, there are planetary specialists on here who would be better placed to give an answer.

[kingsbishop]

On 25/11/2022 at 19:49, DaveS said:

Oh well, you didn't make that clear in your original post.

For planetary or double stars the normal route is lucky imaging to dodge the seeing.

As a DSO imager it's not really my field, there are planetary specialists on here who would be better placed to give an answer.

Still I can only image so much and I like to do visual Mabye the MATX adaptive optics when it comes out I wonder if planewave adaptive optics would do the trick?

[Franklin]

I've always been under the impression that adaptive optics were something that professional observatories are equipped with, due to the expense.

I suppose an Adc could be seen as adaptive, though I don't know if folk use them for visual, I've never used one, but planetary imagers seem to like them.

Being patient and waiting at the eyepiece for those moments when the seeing settles and all the detail pops into view, however fleetingly, is what makes the experience so magical for me. Like when you're observing the Moon at silly high powers and it's all a bit of a mush, focus difficult to attain, and then suddenly it freezes and just looks etched, like a high-definition image from a Lunar Orbiter. 

[vlaiv]

@kingsbishop

I've read your question in latest closed thread, so I'll give you brief answer on that one.

https://en.wikipedia.org/wiki/Angular_diameter

There is handy table containing some angular diameters that might be of interest - like Uranus, Neptune, some minor planets and moons of larger planets.

In any case, objects that you are talking about - are about 4" or less in diameter (in fact - most are less than 1" in diameter).

Largest amateur telescopes are up to 20 inch or so in diameter, while most are 8" and below.

20" telescope will have 0.51" Airy disk diameter, while 8" telescope has 1.28" Airy disk diameter.

Even if you could mount visual adaptive optics system on amateur type telescope - limiting factor would not be the atmosphere but rather resolving power of the aperture. In order to fully start to exploit adaptive optics with its small isoplanatic angle - you need to have aperture large enough to be able to resolve detail over such a small angle.

We are talking here about diameters expressed in meters and not inches.

As far as MATX "adaptive optics kit" - I don't have anything special to say except that it looks like a scam from very sketchy information that I've been able to find.

I've just seen one youtube video where two blokes - don't even give their full names although they do say that they work at University of Riga in Latvia (so we can't fact check that) - talk about their "product" - next to what they refer to 12" scope, although it is clearly 8" skywatcher F/5 newtonian with some gadgets and ZWO camera mounted on it.

Yep, that is "12" newtonian - see 0:25 of this video:

https://www.youtube.com/watch?v=hAfi1yT-gSw

(note call to investors at the end the video)

[geoflewis]

1 hour ago, Franklin said:

I suppose an Adc could be seen as adaptive, though I don't know if folk use them for visual, I've never used one, but planetary imagers seem to like them.

I do use my ADC for visual and find it very helpful, particularly on Saturn with it at such a low elevation from the UK recently.

[DaveS]

What @Franklin has said. For visual your eye-brain combination will do an excellent job of fighting the seeing, while for planetary, "lucky imaging" is the way to go.

Both will save you a shed load of money and a world of pain in getting it to work.

For DSO imaging the jury is still out, but the consensus is "maybe".

[Franklin]

41 minutes ago, geoflewis said:

I do use my ADC for visual and find it very helpful

That's good to know Geof, will have to get hold of one and give it a go!

[neil phillips]

18 minutes ago, Franklin said:

That's good to know Geof, will have to get hold of one and give it a go!

Unlike seeing, varying. Prismatic dispersion is fairly constant. I don't think the eye will compensate for the extra blur occurring due to dispersion. As such Geof's observation holds weight I think.

Edited December 4, 2022 by neil phillips

[geoflewis]

1 minute ago, neil phillips said:

Unlike seeing, varying. Prismatic dispersion is fairly constant. I don't think the eye will compensate for the extra blur occurring due to dispersion. As such Geof's observation holds weight think.

I find that the dispersion on Saturn’s rings is quite marked visually when Saturn is low elevation and observed at high magnification, which I can get with the C14, so much so that I see 3 sets of rings, red, blue and a blurred colour image in between. The ADC fixes that very well.

[ONIKKINEN]

7 minutes ago, geoflewis said:

I find that the dispersion on Saturn’s rings is quite marked visually when Saturn is low elevation and observed at high magnification, which I can get with the C14, so much so that I see 3 sets of rings, red, blue and a blurred colour image in between. The ADC fixes that very well.

Dont need a 14" scope for that, my 8 inch shows clearly separated RGB rings with Saturn at 10-14 degrees. My 90mm, almost does it too, there i can see that there is clear extra fuzz on both sides but its not an obvious separation like in the 200mm.