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Visual Ha vs images


jetstream
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I am wondering if anyone can put up an image of what I can expect to see visually through a Ha scope? The scopes considered are a 60mm Lunt SS and a Quark/SW120ED/32mm plossl combo. I have never looked through a Ha scope but get great white light views with the 120mm. Thanks, Gerry

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Gerry,

Michaels post called " January 17 2015 big 47........."  in solar imaging. The 5th image down named "Pseudo Colour" is the nearest to what I see visually through the Lunt 60mm, I am not sure how it would look with the kit you mentioned.

The differences are:-

  1.  The surface detail comes and goes into view and is not fixed like in the image,( now you see it, now you don't)
  2. The prominences I see through the Lunt are much brighter
  3. The size of the whole disc through the Lunt is a lot smaller than in the image, thus the detail is smaller
  4. I believe seeing the whole disc through the Quark requires a focal length around 460mm

If you hang on 1 week 4 days I can let you know

Are you thinking of joining the light side :evil:  :grin:

Edited by Pig
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Shaun and Shane tell it right, Gerry. I'm in awe of what the imagers on SGL produce but there is no way you will pick up similar views through the eyepiece. Received wisdom from the more knowledgeable among us tells me it has to do with the camera being able to store photons while our eyes cannot.

Nevertheless, viewing in Ha is very close to being addictive .... If you decide to 'take the plunge' I'm pretty sure you will not be disappointed.

p.s. 'Shaun and Shane' seems like something out of a Connery impersonation ...

:-))

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I agree with Gordon but honestly in my 100mm PST mod, the views are not that far off many images I see, especially of proms which are often considerably more detailed in my eyepiece. I can only compare with my PST in standard mode (40mm) which was still great but not nearly as detailed.

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Thanks all! Shaun if I can see visually what Michaels image shows or close, I'll be more than happy, I was wondering because in white light the 120ED gives me views that look as least as good as a lot of images. I kind of wondered if the image may "come and go" given the extremely tight and constantly changing wavelength of Ha, by that I mean by a very small angstrom amount- thanks for confirming a suspicion.

Yes I will be joining the "Light Side"! lol! :grin:

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I agree with Gordon but honestly in my 100mm PST mod, the views are not that far off many images I see, especially of proms which are often considerably more detailed in my eyepiece. I can only compare with my PST in standard mode (40mm) which was still great but not nearly as detailed.

Thanks for the info Shane, great to know that extra aperture pays off, I've been keeping track of my daytime seeing this winter and it's much worse than I thought! Night time can be great quite often strangely (fortunately!). The 32mm TV plossl will be ordered in anticipation of a Ha choice and will work in the 120mm WL under sketchy conditions.

Your PST mod sounds very good Shane-many Kudos!

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Gerry,

Your better off with the angels and the righteous as apposed to the shades and the lost souls :shocked:

Gordon,

Are one of the Bond girls a prize ? if not I will give Shane the points, after all he is a Mod and can pull rank :grin:

Edited by Pig
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Shaun, after hunting down faint things at night it is such a nice feeling to be able to see lots of detail, which is why I love lunar and solar. In the summer, sitting in the shade, I go for a peak at the sun, back in the shade for a sip, back to the scope... :grin: Life of Riley?!

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Remember, I took the image mentioned above through a 35mm instrument. Much of that detail is visible in the scope, although the finer detail tends to come and go. A bigger instrument like the Lunt 60THa (I had a look through Olly's scope a few years back) should be able to pick that up. A Quark-120ED combo should show more.

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Remember, I took the image mentioned above through a 35mm instrument. Much of that detail is visible in the scope, although the finer detail tends to come and go. A bigger instrument like the Lunt 60THa (I had a look through Olly's scope a few years back) should be able to pick that up. A Quark-120ED combo should show more.

Michael, thankyou for bringing me (us?) back to reality. (It wouldn't have been right to say back to earth, would it!?) I was thinking about how I could best tell my missus that I really needed to boost my aperture for Ha viewing but it's not really necessary. 'Much of that detail is visible in the scope' nails it.

Gerry, join us sun lovers. You may not get a tan but you'll be hap-hap-happy.

Shaun, you get your mind off Bond girls, you rascal! You have enough to look forward to over the next .... oh my, what is it again? week and 3.5 days ....? Sheesh! (Or is that too much Shaun and Shane and Connery again?)

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Michael, thankyou for bringing me (us?) back to reality. (It wouldn't have been right to say back to earth, would it!?) I was thinking about how I could best tell my missus that I really needed to boost my aperture for Ha viewing but it's not really necessary. 'Much of that detail is visible in the scope' nails it.

Gerry, join us sun lovers. You may not get a tan but you'll be hap-hap-happy.

Shaun, you get your mind off Bond girls, you rascal! You have enough to look forward to over the next .... oh my, what is it again? week and 3.5 days ....? Sheesh! (Or is that too much Shaun and Shane and Connery again?)

But Gordon, of course you need to increase the aperture of your H-alpha kit :D

I am saving up for a Quark (and a bigger camera to go with it)

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Just to second all the opinions that the visual detail is pretty amazing in anything from 60mm upwards.

My Quark in the Tak 60 easily outperforms a PST, in the 120ED it is pretty amazing.

I bought the Quark because I was finding the PST just couldn't compete with the herschel wedge views in the TV85 which gives views which I think exceed many images.

I am soon going to be in a position to try a crazy experiment of the Quark in a SW 150 f5, with Denk binoviewers and Zeiss 25mm orthos. Should be pretty amazing, the views with the binoviewers in the TV85 the other day were stunning enough!

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Gerry, these are two quite appalling hand held iPhone shots through the Quark. I can't remember which scope, possibly either the 85 or 120.

Imagine these but sharp, with fine and intricate detail visible and you are somewhere near.

1b5e947a0f587299f761bc0f9dbf5e3b.jpg

63a350b8b00a84a4a9b1cc2035f47d8a.jpg

Stu

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Hi BigMak! Thanks for posting the pictures and relating your experiences. That prom is awesome, I love the look of Ha and can't wait to try it. I can be quite a snail when it comes to decisions at times though lol!

Now I need to figure out if my UV/IR filter is adequate as a mini ERF for the 120mm. It is made of IR absorptive KG3 glass, with reflective UV coatings, today a couple of emails will be fired off in pursuit of more info.

ps did I read Zeiss orthos?! :grin:

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Hi BigMak! Thanks for posting the pictures and relating your experiences. That prom is awesome, I love the look of Ha and can't wait to try it. I can be quite a snail when it comes to decisions at times though lol!

Now I need to figure out if my UV/IR filter is adequate as a mini ERF for the 120mm. It is made of IR absorptive KG3 glass, with reflective UV coatings, today a couple of emails will be fired off in pursuit of more info.

ps did I read Zeiss orthos?! :grin:

You are welcome Gerry. The views are pretty stunning I must say. As a bit of a qualifier though, one problem with the 120ED with the Quark is that you need good conditions to use it because of the high mag. With a 32mm plossl, the x4.2 barlow combined with the 900mm focal length means you are at x118.

I find the Quark excellent in the 85 too as it has a lower mag so is more forgiving. I believe that the surface detail contrast is lower than a Lunt 60 for example, but the detail is similar or better due to the larger aperture.

One more thing to remember, the FOV is determined by the etalon aperture on the quark, 21mm I believe, so in the 120ED (and most scopes over 450 ish mm focal length) it is this which limits the fov rather than the eyepiece field stop or the eyepiece afov. I believe the only way around this is a focal reducer before the Quark, something I've tried but haven't been able to get to focus. A reducer after the Quark only reduces the mag, it doesn't improve the FOV.

Zeiss? Who mentioned Zeiss? ;-)

I picked these up a while ago, don't know too much about them to be honest but I think they are ex microscope eyepieces with custom adaptors. One advantage is that they have diopter adjustment to balance the focussing in the binoviewers.

Transmission is excellent, light scatter very well controlled too. Lovely sharp eps

66a4bbccd7341319924f32a683d30dc9.jpg

90d03a87e8bde8a7f0a3679e617a7052.jpg

One thing is for sure, I now have Ha capability to match the Herschel Wedge which is fab.

Cheers,

Stu

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I don't think I have seen any image that truly matches what you see through the eyepiece (some imagers try to get close to the eyepiece view and some don't, I am in the latter camp), I think it comes down to that the eye/brain is very different to the camera/computer screen. My best guess is that a couple of things in play here are:

- the eye can see far finer detail than a camera

- the eye sees a much greater range of brightness than can be shown on a computer screeen and the sun has a big range of brightness - this especially applies to proms. When I try and process them, they seem so dark compared with the disc, but through the eyepiece, the proms look pretty bright (unless it's a really faint one!)

Now, which is better, the camera view, or the eyepiece view? It depends on you, I guess! A 20 inch dob on deep sky will seem inferior for some imagers than their cooled CCD, while some of the dob mob don't feel any pull towards imaging. Which is better? BOTH! :laugh:

Edited by Luke
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I don't think I have seen any image that truly matches what you see through the eyepiece (some imagers try to get close to the eyepiece view and some don't, I am in the latter camp), I think it comes down to that the eye/brain is very different to the camera/computer screen. My best guess is that a couple of things in play here are:

- the eye can see far finer detail than a camera

- the eye sees a much greater range of brightness than can be shown on a computer screeen and the sun has a big range of brightness - this especially applies to proms. When I try and process them, they seem so dark compared with the disc, but through the eyepiece, the proms look pretty bright (unless it's a really faint one!)

Now, which is better, the camera view, or the eyepiece view? It depends on you, I guess! A 20 inch dob on deep sky will seem inferior for some imagers than their cooled CCD, while some of the dob mob don't feel any pull towards imaging. Which is better? BOTH! :laugh:

I agree with the higher dynamic range if the eye, which is why I needed two exposures and compress the dynamic range with gamma correction.

I think the image captures slightly finer detail, however.

You are right that you need both!

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Stu, I can only imagine the views through that bino set up, very nice equipment, impressive actually.

Thanks Gerry. The binoviewers do work very nicely. I've tried different models in the past and not got on with them but the Denks are excellent.

I've no idea how the SW150 f5 will work. CA should be no issue but SA may be. We'll see, but I got it for a good price so no harm if it doesn't work. Larger aperture and shorter focal length than the 120 might work. Watch this space.

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