November 26, 2015: Lunt Ca-K B1800 SECOND light!!

[michael.h.f.wilkinson]

First set of images stitched in my second go at Ca-K in a single day. MUCH better seeing and MUCH better focus yields a MUCH better image

Grey scale:

Pseudo colour:

[Montana]

Excellent!!! you are already coming on in leaps and bounds from the first :)

Alexandra

[dazzaa1966]

Excellent images Michael

[Ibbo!]

great first day out with the new toy

[David Smith]

Cracking images! Welcome to the Calcium club

[michael.h.f.wilkinson]

Thanks everyone! Glad I got of to a flying start

[Pete Presland]

A great start to your Ca-K imaging there really is something about the different views of those images.

[Pete Presland]

Thanks everyone! Glad I got of to a flying start

Did you try it visually or is that not possible?

[michael.h.f.wilkinson]

Did you try it visually or is that not possible?

No I didn't. I doubt I would see anything, and I didn't have a star diagonal + EP handy to try first time round.

[laudropb]

Very nice. Well done Michael

[Pete Presland]

No I didn't. I doubt I would see anything, and I didn't have a star diagonal + EP handy to try first time round.

I thought I had read the Ca-K was purely an imaging tool. Looking forward to seeing your future images.

Sent from my GT-N7100 using Tapatalk

[michael.h.f.wilkinson]

I thought I had read the Ca-K was purely an imaging tool. Looking forward to seeing your future images.

Sent from my GT-N7100 using Tapatalk

Youngsters might be able to see a little, but as the eye ages the cornea and lens turn slightly yellowish, blocking out the shorter wavelengths completely. I didn't even want to try if I could see something, as it is really borderline UV-A

[Drop Of Sun]

Cor, that was some swift progress.

[michael.h.f.wilkinson]

Cor, that was some swift progress.

Processing was identical, seeing and focus was a giant leap further

[Dinsdale Piranha]

Very nice. I do quite like CaK imaging myself.

What camera / Scope did you use. I agree that focusing seems quite critical, more so than for Ha.

DP

[Dinsdale Piranha]

Opps, can't edit.

When I first got my CaK (Lunt diagonal) -  I wasn't expecting to see anything visually. But in actual fact even though I'm north of 40y, I could see most of the detail that I was seeing on the imaging side. 

So its worth a look even if you think you cant.

DP

[michael.h.f.wilkinson]

Very nice. I do quite like CaK imaging myself.

What camera / Scope did you use. I agree that focusing seems quite critical, more so than for Ha.

DP

I used my APM 80mm F/6 triplet, the new Lunt B1800 Ca-K module and a Meade 3x TeleXtender with my ASI174MM camera. The I am planning to attach a Beloptic Tri-Band ERF, which passes only three narrow bands around Ca-K, solar continuum, and H-alpha, in front of the scope. This is not strictly necessary but can reduce tube currents due to the heat build-up in the OTA. I can then also rapidly switch between Ca-K, white light, and H-alpha.

Opps, can't edit.

When I first got my CaK (Lunt diagonal) -  I wasn't expecting to see anything visually. But in actual fact even though I'm north of 40y, I could see most of the detail that I was seeing on the imaging side. 

So its worth a look even if you think you cant.

DP

Very interesting to hear. I will pack a star diagonal next time to check what may be seen

[paulastro]

Beautiful shots, I especially like the colour version.  Many thanks.

[Dinsdale Piranha]

I used my APM 80mm F/6 triplet, the new Lunt B1800 Ca-K module and a Meade 3x TeleXtender with my ASI174MM camera. The I am planning to attach a Beloptic Tri-Band ERF, which passes only three narrow bands around Ca-K, solar continuum, and H-alpha, in front of the scope. This is not strictly necessary but can reduce tube currents due to the heat build-up in the OTA. I can then also rapidly switch between Ca-K, white light, and H-alpha.

Very interesting to hear. I will pack a star diagonal next time to check what may be seen

Thanks Michael. Your results are really very good. I'd like to say that I understand the "Beloptic Tri-Band ERF" but I don't

I am a little confused lol. I have the B600 - which is obviously a different module to yours. But I thought that they were essentially a similar design - just for different FL/Objs.

Mine is a diagonal already - so I just pop an EP in...

[michael.h.f.wilkinson]

Thanks Michael. Your results are really very good. I'd like to say that I understand the "Beloptic Tri-Band ERF" but I don't

I am a little confused lol. I have the B600 - which is obviously a different module to yours. But I thought that they were essentially a similar design - just for different FL/Objs.

Mine is a diagonal already - so I just pop an EP in...

Mine is a straight through one which is handy for imaging, I find.

The 85mm Tri-Band ERF (energy rejection filter) from Beloptic was an experimental piece of kit, and I gather only six of them exist. It is an interference filter, which is designed to pass three wavelength bands, and reflect all other wavelengths.

Putting this in front of the scope means that much less light enters the scope in the first place. For many H-alpha filters, it is essential to do this, or you will overheat your etalon. The Daystar Quark has one built in, just like the Ca-K units from Lunt, so they don't strictly need an ERF unless the aperture of the scope is bigger than some maximum (4" in the case of the Ca-K units). However, putting an ERF in front of the scope means that light (and therefore heat) that you do not need does not enter the OTA, and therefore the scope stays cooler. This means that there is less turbulence inside the scope due to temperature differences.

[Dinsdale Piranha]

Interesting thanks Michel.

I didn't realize that there was a difference in design between the B600 and other models. I never really look at the other versions as I have a ST102 - which apart from the focuser is a cracking little scope for Narrowband

Cheers

[michael.h.f.wilkinson]

Interesting thanks Michel.

I didn't realize that there was a difference in design between the B600 and other models. I never really look at the other versions as I have a ST102 - which apart from the focuser is a cracking little scope for Narrowband

Cheers

There are straight-through and diagonal models of the B600, B1200 and B1800 as well. The design of the B1200 and B1800 diagonal ones is essentially the same as your B600, it is just the diameter of the blocking filter that differs. The straight through versions just lack the mirror included in the diagonal ones. Optically they are the same in all other respects.

[Drop Of Sun]

That's interesting, I have half an eye on the Calcium Quark, which is a very slightly higher wavelength. My wife has no interest in CaK for imaging but is interested in sharing a Calcium Quark if there is a fair chance she will be able to observe with it.

Opps, can't edit.

When I first got my CaK (Lunt diagonal) -  I wasn't expecting to see anything visually. But in actual fact even though I'm north of 40y, I could see most of the detail that I was seeing on the imaging side. 

So its worth a look even if you think you cant.

DP

[michael.h.f.wilkinson]

I had considered the Calcium Quark, but noticed the B1200 was not much more expensive, and when I got a sizeable bonus for being employed at the University of Groningen for 25 years I could even afford the B1800. There were a few considerations: The Calcium Quark is a bit of an unknown quantity, whereas the Lunt Ca-K modules have a solid reputation. Furthermore, the Calcium Quark needs to heat up, whereas the Lunt works essentially immediately. I did consider the visual aspect a bit, but ultimately it was the heating issue that tipped the balance.

[Drop Of Sun]

My plan is to wait for some first lights and images from the Calcium Quark, as I did with the h-alpha Quark. I should take a little time to understand the Lunt options too, really I would like something that will work with my scopes from 60mm to 120mm without any problems fitting, they have various focusers so I don't know if that may be an issue or not. Maybe I need to email Lunt.

I'm expecting the Lunt to beat the Calcium Quark for imaging as the Quark is said to be approx. 5Å FWHM, but I guess the pictures will tell us more when they come through? For me so long as it's not too away from the Lunt CaK images, that would be good enough. And I'm keen to hear how many people can or cannot see detail with it!

I guess it all depends on needs, I don't really find the Quark h-alpha much hassle the way I use it.

I had considered the Calcium Quark, but noticed the B1200 was not much more expensive, and when I got a sizeable bonus for being employed at the University of Groningen for 25 years I could even afford the B1800. There were a few considerations: The Calcium Quark is a bit of an unknown quantity, whereas the Lunt Ca-K modules have a solid reputation. Furthermore, the Calcium Quark needs to heat up, whereas the Lunt works essentially immediately. I did consider the visual aspect a bit, but ultimately it was the heating issue that tipped the balance.