Search found 498 matches

by krakatoa1883
Sun Sep 22, 2019 6:40 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Experimenting calcium imaging with small refractors
Replies: 49
Views: 4458

Re: Experimenting calcium imaging with small refractors

An apochromat is certainly not necessary, actually my preferred refractor for CaK imaging is a 80 mm f/11.3 TMB achromat. However a 115 mm achromat well corrected @393 nm would be too long, at least for my observing site. This apo is not only well corrected but also much more versatile.
by krakatoa1883
Sun Sep 22, 2019 12:21 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Experimenting calcium imaging with small refractors
Replies: 49
Views: 4458

Re: Experimenting calcium imaging with small refractors

Resuming this thread as I started calcium imaging with a 115mm f/7 Tecnosky triplet refractor. First results seem promising, the scope is better corrected than my previuos ones except the long focus TMB 80. If I am not wrong Peter Zetner obtained some very good images (better than mine) by using of ...
by krakatoa1883
Sun Sep 22, 2019 12:03 pm
Forum: This is SolarChat !!
Topic: animation 20 sept big prom
Replies: 11
Views: 68

Re: animation 20 sept big prom

Great animation, Paul. I too experienced that kind of artifacts when wind or turbulence are strong. Sometimes I am able to get rid of the problem by selecting and stacking only few frames and/or adding some very large alignment poins in AS3! within the dark area.
by krakatoa1883
Sun Sep 22, 2019 11:35 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: What do you think is the most versatile high resolution solar telescope design?
Replies: 43
Views: 1823

Re: What do you think is the most versatile high resolution solar telescope design?

Thanks for the detail. Unfortunately that Meade barlow is now difficult to find except in the used marked but I will try anyway. I tried yesterday to modify an airspaced meniscus Barlow but results were disappointing, no gain in contrast compared with the barlow in the original configuration. May be...
by krakatoa1883
Sat Sep 21, 2019 2:43 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: What do you think is the most versatile high resolution solar telescope design?
Replies: 43
Views: 1823

Re: What do you think is the most versatile high resolution solar telescope design?

Interesting, thanks for sharing. It would be useful to know which brand is the Barlow you used because not all triplet barlows are equal. The spaced element of many triplets is a converging meniscus which is used mainly to correct the divergence of the marginal rays. However other triplets - some GS...
by krakatoa1883
Mon Sep 16, 2019 8:26 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: What do you think is the most versatile high resolution solar telescope design?
Replies: 43
Views: 1823

Re: What do you think is the most versatile high resolution solar telescope design?

I think the graf you are showing for SCT spherochromatism in the blue end is way too exaggerated for optical engineers "blue" means the F line that is 486nm. At this wavelength SCs are still usable as one can see from the graph posted by Christian as well as in spot diagrams for SC. However CaK is ...
by krakatoa1883
Mon Sep 09, 2019 6:30 pm
Forum: This is SolarChat !!
Topic: Prom Animation 25th August '19_Colour Added
Replies: 27
Views: 419

Re: Prom Animation 25th August '19_Colour Added

Absolutely fantastic, Stu.

Is there any tutorial for making animations with IMPPG ? Thks.
by krakatoa1883
Fri Sep 06, 2019 3:42 pm
Forum: This is SolarChat !!
Topic: Quark Testing Round 5
Replies: 6
Views: 123

Re: Quark Testing Round 5

To my eyes negative 1 or zero seem the best, however I agree with Valery, send it back, no good.
by krakatoa1883
Mon Aug 19, 2019 3:22 pm
Forum: This is SolarChat !!
Topic: Saturday Sun, Polar Faculae and Bright Points - 17th August
Replies: 14
Views: 242

Re: Saturday Sun, Polar Faculae and Bright Points - 17th August

Fine images, Mark. I too use my Quark to darken filaments through my Lunt-mod scope, my results depend much on finding the best matching tuning of both systems, not always easy to do.
by krakatoa1883
Mon Aug 19, 2019 3:15 pm
Forum: This is SolarChat !!
Topic: Saturday Solar 17th August - Celestron Omni CaK testing
Replies: 10
Views: 190

Re: Saturday Solar 17th August - Celestron Omni CaK testing

Nice discs Alexandra. If the 100mm is the ED version it should be capable of doing much better than that in fine seeing conditions. I have it and in CaK or CaH is really fine at full aperture.
by krakatoa1883
Sun Aug 11, 2019 1:14 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: it seems that my Quark is not reaching the working temperature
Replies: 13
Views: 444

Re: it seems that my Quark is not reaching the working temperature

Getting f/30 by reducing the aperture will produce a faint image unless observed at the lowest possible magnification. Instead try to increase the f.l. with a good amplifier, there is no image degradation, I did it many times with my Quark and it works fine. Changing your yellow ERF with a D-ERF cou...
by krakatoa1883
Tue Aug 06, 2019 8:51 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: it seems that my Quark is not reaching the working temperature
Replies: 13
Views: 444

Re: it seems that my Quark is not reaching the working temperature

Quark's etalon needs a f/30 light cone to work properly, better around f/40, so increasing the f/ratio (possibly without reducing aperture) should produce better results. Try different setups and see which one works best.
by krakatoa1883
Tue Aug 06, 2019 3:16 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: it seems that my Quark is not reaching the working temperature
Replies: 13
Views: 444

Re: it seems that my Quark is not reaching the working temperature

Hi Roman If your Quark is exposed to sunlight while observing it may become too hot for tuning. For example my one needs only a modest heat input and works best at -5 position. Under the Sun it reaches tuning without any power supply and if connected to the mains the light remains orange. Try shield...
by krakatoa1883
Thu Aug 01, 2019 2:08 pm
Forum: This is SolarChat !!
Topic: Solar Sunday
Replies: 22
Views: 468

Re: Solar Sunday

Superb CaK detail, Alexandra, did you take it at full aperture ?
by krakatoa1883
Wed Jul 17, 2019 4:43 pm
Forum: This is SolarChat !!
Topic: AR12403 (20140819/20140829) | Pedro RE'
Replies: 11
Views: 294

Re: AR12403 (20140819/20140829) | Pedro RE'

Excellent images, very well processed.
by krakatoa1883
Tue Jul 16, 2019 11:47 am
Forum: This is SolarChat !!
Topic: Solar Images taken May 9th 2019 and a question.
Replies: 14
Views: 640

Re: Solar Images taken May 9th 2019 and a question.

Good result, granulation is evident. With a 0.5x focal reducer you can image the full disc.
by krakatoa1883
Mon Jul 15, 2019 4:44 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Why my Quark always refused to work...
Replies: 20
Views: 1512

Re: Why my Quark always refused to work...

Replacing the BF may help however incorrect tuning and poor seeing may also lead to obtain ill-defined images. Hope your new BF will improve things.
by krakatoa1883
Mon Jul 15, 2019 1:19 pm
Forum: This is SolarChat !!
Topic: My first CaK image
Replies: 8
Views: 238

Re: My first CaK image

Thanks Alexandra, very kind :)
by krakatoa1883
Mon Jul 15, 2019 8:28 am
Forum: This is SolarChat !!
Topic: My first CaK image
Replies: 8
Views: 238

Re: My first CaK image

Thanks to all, this CaK device is indeed definitively more funny than my calcium Quark :D I noted that the filter is recommended up to 100mm aperture, I suppose an ERF is required for larger refractors but the 2" tube end has no thread for my blue CCD filter, is there any way to make an adaptation ?
by krakatoa1883
Sun Jul 14, 2019 4:43 pm
Forum: This is SolarChat !!
Topic: My first CaK image
Replies: 8
Views: 238

My first CaK image

Having used a Quark calcium for two years I eventually decided to try some CaK imaging. From the European Lunt dealer I found a good offer for a straight-through B600, which I preferred to the diagonal version as it has a shorter optical path (I have also a H-alpha BF1200 ST and indeed it is more ve...
by krakatoa1883
Sun Jul 14, 2019 3:55 pm
Forum: This is SolarChat !!
Topic: Today's SUN (20190713) | FDs (3 lights)
Replies: 10
Views: 288

Re: Today's SUN (20190713) | FDs (3 lights)

Beautiful discs, Pedro, very sharp.
by krakatoa1883
Sun Jul 14, 2019 3:51 pm
Forum: This is SolarChat !!
Topic: July 7th Images
Replies: 14
Views: 366

Re: July 7th Images

Nice images, Brian, I liked H-alpha in particular. WL and CaK appear quite dark on my screen, they could be improved by using of curves tool or a high pass filter. I tried to do so but some artifacts emerged at the top limb of the full disc. At full resolution CaK is impressive, very well resolved.
by krakatoa1883
Wed Jul 10, 2019 10:31 am
Forum: This is SolarChat !!
Topic: Sunday Sun 7th July '19_Cycle 25
Replies: 12
Views: 435

Re: Sunday Sun 7th July '19_Cycle 25

Your CaK discs are really super, Stu, very effective setup for this wavelength.
by krakatoa1883
Wed Jul 10, 2019 10:30 am
Forum: This is SolarChat !!
Topic: Full disc July 6
Replies: 9
Views: 329

Re: Full disc July 6

Thanks Alexandra, Stu.
by krakatoa1883
Mon Jul 08, 2019 9:56 am
Forum: This is SolarChat !!
Topic: Replacement Quark ERF
Replies: 4
Views: 213

Re: Replacement Quark ERF

Actually it does both jobs, cuts etalon harmonics and protects the etalon from excessive heat. Unfortunately this kind of filters are not designed specifically for solar observing and shall therefore be protected by using of some energy rejection device placed in front of them. Based on what occurre...