September Solar Challenge

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September Solar Challenge

Post by Montana »

An interesting subject really

For all Calcium K and Calcium H owners

Please have a look visually (if safe to do so - depending on your filter system)

Please add in the comments answers to these questions:

Calcium II K or Calcium H (delete as appropriate) Filter type =

1. Can you see the Sun at all?

2. What details?

3. Can you describe the colour?

4. How old are you (optional)?

5. Have you had cataract surgery (optional)?

6. Have you ever looked visually in this wavelength before or is this the first time?

It would be interesting to get an overall feel for how people use and see in this wavelength.

Alexandra


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Re: September Solar Challenge

Post by Carbon60 »

Hi Alexandra,

I know from experience I can’t see anything at all in CaK.
I first tried about 6 years ago and couldn’t see anything then.
I’m 60 next week :roll:
Never had cataract

Thank goodness we have cameras that detect at this wavelength. Useless and unattainable visually for me otherwise.

Stu.


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Re: September Solar Challenge

Post by JochenM »

1. Can you see the Sun at all? Yes

2. What details? The disk is very faint and requires effort to view (compare it to looking through an eyepiece with very low exit pupil). Active regions can be perceived as something being there, but without any detail.

3. Can you describe the colour? Faint violet.

4. How old are you (optional)? 40

5. Have you had cataract surgery (optional)? No

6. Have you ever looked visually in this wavelength before or is this the first time? Tried it a few times over the past few years. The experience is always as described above.


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Re: September Solar Challenge

Post by Montana »

I had better add myself :)

Calcium II K ) Filter type = Lunt B1800 wedge

1. Can you see the Sun at all?
Yes, fairly well (not as bright as Halpha)

2. What details?
I can see plage and sunspots easily, super granulation comes into view after a bit of dark adaption.

3. Can you describe the colour?
pale lavender colour

4. How old are you (optional)?
49

5. Have you had cataract surgery (optional)?
No

6. Have you ever looked visually in this wavelength before or is this the first time?
Many times and enjoy it. Tried with the PST years ago and could barely see that a Sun was there at all

Alexandra


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Re: September Solar Challenge

Post by robert »

Calcium II K. Filter type = Lunt CaK B600 module

1. Can you see the Sun at all?
Yes just, but not well enough to see the focus point

2. What details?
No details just a blurred disk

3. Can you describe the colour?
A beautiful deep violet colour

4. How old are you (optional)?
71

5. Have you had cataract surgery (optional)?
No

6. Have you ever looked visually in this wavelength before or is this the first time?
Yes for 14 years maybe (since 2008 and when I was 57) and initially I could see spots and a sharp edge to the disk

I am definitely a fan of cameras and digital imaging!
Robert


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Re: September Solar Challenge

Post by nicspenceryork »

Calcium K

Filter type = Lunt 1200 Module

1. Can you see the Sun at all? Yes

2. What details? It depends on the eye I looked through! I saw sunspots, plage & supergranulation with my right eye without glasses and only a very vague difference in shade of purple on the surface with my left! I have a stronger lens in my reading glasses to help my left eye though so it might've been a question of focus. I couldn't see the details as well with my right eye when I looked through my glasses although they do have some sort of anti reflection coating on which reduces the amount of blue light entering the eye. They say this blue light is emitted by digital devices. I don't understand it well enough to know whether it's that coating which is stopping me seeing the details in CaK with glasses! This experience was consistent over time, so I believe the effect to be true of my eyes rather than a change in seeing or focusing of the telescope. I've had several vitreous detachments in my right eye in the past. Because of that I tend to observe with a camera otherwise all I tend to see is whatever the shape of the squiggly lines or 'cobwebs' are in my eye at the time of observing. This is particularly weird with h alpha as I see filaments a-plenty that aren't there!

3. Can you describe the colour? Again, it was different for each eye! With my right eye it was lilac/lavender and with my left it was darker and more of a mauve/purple. I googled shades of purple and found inconsistency from site to site, maybe we need a colour chart to choose from!

4. How old are you (optional)? 53 next week!

5. Have you had cataract surgery (optional)? No

6. Have you ever looked visually in this wavelength before or is this the first time? No this was my first time!

This is so interesting,
Nic


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Re: September Solar Challenge

Post by steveward53 »

I don't have access to Calcium kit here , but the last time I had a look at it was at the IAS a few years back , either Mark T or Gary P's set up.

Couldn't see anything bar a very dark purple smudge ... was about 53 at the time so even less chance now ... !


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Re: September Solar Challenge

Post by ffellah »

Hello Alexandra and all: I was out this morning and did some visual in CaH

Calcium H Filter type = CaH Quark

1. Can you see the Sun at all ? Yes, definitely

2. What details? Sunspots very clearly, active areas around the sunspots very clearly, plages more faint but definitely visible all around and in the center of the disk

3. Can you describe the colour ? Medium blue

4. How old are you ? 67

5. Have you had cataract surgery ? Yes, 5 years ago

6. Have you ever looked visually in this wavelength before or is this the first time ? This is my fourth time

Franco


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Re: September Solar Challenge

Post by marktownley »

I've not looked visually for quite a few years now as my CaK filters are 'home made' and while fine for imaging i'm not risking UV for visual.

Last time I did look though I needed to be dark adapted to see anything, I could see deep purple disk, brighter plage and sunspots.


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Re: September Solar Challenge

Post by sywong2000 »

Filter is Daystar Quark Cal H

1. Can you see the Sun at all? Yes

2. What details? Sunspots in a group of 3

3. Can you describe the colour? A deep blue with purple cast

4. How old are you (optional)? 46

5. Have you had cataract surgery (optional)? No

6. Have you ever looked visually in this wavelength before or is this the first time? First time

The image shows pretty dark after a 4x (roughly F/28) - I have similar setup with Franco's and I should definitely try removing the powermate which would give me a much brighter view! or better with a faster scope!

Stephen


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Re: September Solar Challenge

Post by MapleRidge »

Hi everyone...

Interesting challenge for sure ;)

My observing and imaging is in the CaK II K using either a Lunt B1200CaK (right angle) or B1800CaK straight through module.

1. Can you see the Sun at all?
I am joining questions 2/3/5 to the top as I have had cataract surgery in my right eye some 5-6 years ago. The non-cataract eye sees a deep purple smudge with no detail or limb noticeable. The eye that had surgery sees the details sharp with beautiful contrast on the disk with the plage and sunspot detail like WL...similar coloration as the untreated eye but with detail :lol: .

4. How old are you (optional)?
57 tomorrow

5. Have you had cataract surgery (optional)?
See above

6. Have you ever looked visually in this wavelength before or is this the first time?
I have looked many times, but really jut use the filter for imaging

Brian


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Re: September Solar Challenge

Post by nicspenceryork »

MapleRidge wrote: Sun Sep 04, 2022 6:19 pm Hi everyone...

Interesting challenge for sure ;)

My observing and imaging is in the CaK II K using either a Lunt B1200CaK (right angle) or B1800CaK straight through module.

1. Can you see the Sun at all?
I am joining questions 2/3/5 to the top as I have had cataract surgery in my right eye some 5-6 years ago. The non-cataract eye sees a deep purple smudge with no detail or limb noticeable. The eye that had surgery sees the details sharp with beautiful contrast on the disk with the plage and sunspot detail like WL...similar coloration as the untreated eye but with detail :lol: .

4. How old are you (optional)?
57 tomorrow

5. Have you had cataract surgery (optional)?
See above

6. Have you ever looked visually in this wavelength before or is this the first time?
I have looked many times, but really jut use the filter for imaging

Brian
We share a birthday! Have a great day tomorrow,
Nic


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Re: September Solar Challenge

Post by MapleRidge »

Thanks Nic...hope you have a great day tomorrow too :D

Brian


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Re: September Solar Challenge

Post by Bastelhannes »

Equipment: Calcium II K ) Filter type = Lunt B1800 wedge
- Telescope: TS-Optics 100 mm F/11 -> why do I explain this? Telescopes are quite different in that wavelength

1. Can you see the Sun at all?
Yes, very well

2. What details?
I can see:
- granulation
- plage
- sunspots

Everything easily

3. Can you describe the colour?
violett glowng

4. How old are you (optional)?
48

5. Have you had cataract surgery (optional)?
No

6. Have you ever looked visually in this wavelength before or is this the first time?
Yes, first time


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Re: September Solar Challenge

Post by pedro »

Like Mark I I've not looked visually for a while. I use my CaK filters mainly for imaging

I remember that visually it is quite challenging to see the FD with a modded CaK PST


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Re: September Solar Challenge

Post by Jordan Konisky »

My eyes: My left eye currently has a cataract that I can see through with near normal vision. As soon as it ripens to the extent that my vision is impacted, I will undergo cataract surgery in that eye. In contrast my right eye underwent cataract surgery 5 or 6 years ago and is clear as a bell.

Calcium II K, Lunt CaK 1800B Diagonal

1. Can you see the Sun at all?
Left eye: all I see is black through the CaK filter. In contrast, that eye provides excellent seeing in HA or WL.
Right eye: Yes.

2. What details?
Through right eye (cataract surgery) I see spots and plage and evidence of supergranulation. Not great resolution, but these features are clearly present.

3. Can you describe the colour?
Right eye: purplish

4. How old are you (optional)? 81

5. Have you had cataract surgery (optional)? Yes, right eye only.

6. Have you ever looked visually in this wavelength before or is this the first time?
First time.


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Re: September Solar Challenge

Post by Montana »

It is so fascinating and interesting to hear all these stories :bow

Alexandra


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Re: September Solar Challenge

Post by Jordan Konisky »

Several years ago, before I was into solar, my astronomy club had a speaker who presented a comprehensive talk on spectroscopy – mostly as it applied to stars. He generated a spectrum for the audience and sought our response as to which colors we could see. He mentioned that those of us who had cataract surgery might be able to see a band that others would not be able to observe. I don’t remember the exact band, but in hindsight, it must have been purple. I could see it with my right eye (cataract surgery), but not my left eye (no cataract surgery) even though I could see the other color bands in both eyes.

Jordan


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Re: September Solar Challenge

Post by torsinadoc »

1. Can you see the Sun at all? Faint purple blur. Barely detectable

2. What details? None. Used b1800

3. Can you describe the colour? Purple

4. How old are you (optional)? 49

5. Have you had cataract surgery (optional)? No

6. Have you ever looked visually in this wavelength before or is this the first time? First time


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Re: September Solar Challenge

Post by JochenM »

This is all very interesting.

I always assumed that when people said that can't see anything in CaK; they meant that detail on the disk isn't there, but the disk itself is perfectly visible (similar to my situation in other words).

You learn something new every day :)


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Re: September Solar Challenge

Post by MapleRidge »

Interesting read with all the reports of the ability of observers to see Ca features. I'd say that Bastelhannes ability to see without cataract surgery seems to be the exception to the trend.

The other point of interest is that we have no participants below the age of 40 by the looks of it.

Brian


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Re: September Solar Challenge

Post by Bastelhannes »

hm.. I thought Montana and Nic could see the details as well. Looks like women see it better than men in natural state. Would be interesting to investigate more in this ( were caves more UV blocking than the open fields? Do male radiate UV to impress the females?).

I am having a visus of about 2.5 (normal is 1.0), this means my resolution is higher (it is a brain thing, not the eye hardware). Maybe this changes some visibility of details close to UV as well.


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Re: September Solar Challenge

Post by MapleRidge »

I stand corrected :o

I should have re-read the posts...all of the negative ones came to mind and I forgot that Nic and Alexandra were more fortunate. As you say, it seems the women have better luck viewing the Ca spectrum in our small sample of the population.

Brian


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Re: September Solar Challenge

Post by Jordan Konisky »

I suggest we all meet in Alexandra’s garden so that we can observe through the same setup under the same conditions. Then again, that’s not the purpose of the challenge, is it.? Rather, it is to share our own experience.


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Re: September Solar Challenge

Post by Ibbo »

I tried with my Tak set up and just managed to see a purlpe blob but I don't think I was anywhere near focus.
I will try with the Eddy the 80 next time out.


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Re: September Solar Challenge

Post by rsfoto »

Hi,

Just a side information which maybe could play a role

https://www.colourblindawareness.org/colour-blindness/

8.3% of men are colourblind while 0.5% of women are ...


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Re: September Solar Challenge

Post by Montana »

Very interesting indeed Rainer, I didn't know anything about the blue-purple thing as in this quote "Being ‘red/green colour blind’ means people with it can easily confuse any colours which have some red or green as part of the whole colour. So someone with red/green colour blindness is likely to confuse blue and purple because they can’t ‘see’ the red element of the colour purple. See the example of pink, purple and blue pen cases above to understand this effect."
Maybe I should have asked the question about colour blindness as well. It also says those taking certain medications or with diabetes can also see colours differently. It is a fascinating subject.

Alexandra


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Re: September Solar Challenge

Post by torsinadoc »

Montana wrote: Mon Sep 12, 2022 5:51 pm Very interesting indeed Rainer, I didn't know anything about the blue-purple thing as in this quote "Being ‘red/green colour blind’ means people with it can easily confuse any colours which have some red or green as part of the whole colour. So someone with red/green colour blindness is likely to confuse blue and purple because they can’t ‘see’ the red element of the colour purple. See the example of pink, purple and blue pen cases above to understand this effect."
Maybe I should have asked the question about colour blindness as well. It also says those taking certain medications or with diabetes can also see colours differently. It is a fascinating subject.

Alexandra
I’m red green color blind


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Re: September Solar Challenge

Post by nicspenceryork »

Following my post in this thread about being able to see CaK features with my right eye without my glasses but not being able to see these features with glasses, I wrote to Vision Express to learn more and here is their reply…
‘Calcium-K telescopes allow you to image the Sun in the blue light of calcium (393.4 nm), however blue coating on your spectacle lenses (Hoya Blue Control) blocks wavelengths in the range of 420-460 nm. So it looks like this particular lens coating is out of the range of 393.4 nm, therefore it will likely stop you seeing what you need to see through the calcium filter. 
If you had a blue coating from a different manufacturer that might not be the case as not all lenses display similar transmissions of blue light and different manufacturers do not agree as to what percentage of blue light should be reflected or transmitted. Usually it is agreed that blue coating on the lenses should cut the wavelengths in the range between 420 and 460 nm.’
A little confused by this (as 393.4 isn’t within the range of 420-460) I asked a learned friend about it, who suggest that they might have omitted an all important ‘and below’ from the sentence.
Thought some of you might find this interesting. So, if you wear glasses and can’t see the CaK features, take them off and try again!
Nic


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