Excellent images, very well processed.

Good result, granulation is evident. With a 0.5x focal reducer you can image the full disc.

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.

Thanks Alexandra, very kind

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 ?

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...

Beautiful discs, Pedro, very sharp.

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.

Your CaK discs are really super, Stu, very effective setup for this wavelength.

Thanks Alexandra, Stu.

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...

You mean the blocking filter, I see. You have to replace it, there is no other solution. Mine too degraded, I bought a new one from Andover.

Great images, and explanations, Mark. Is the full disc a mosaic ?

Thanks to all, very much appreciated

Not much stuff to see today, a couple of filaments and some minor proms, the most interesting on the NE limb. I have taken only a full disc with my Lunt LS50 and B1200. However based on SDO imagery a high southern latitude active region is now visible to the east, it's small but looks promising. Som...

Finally the new BF from Andover arrived and indeed it made a huge difference, so my Quark is now returned as new. I am very happy because the etalon of my unit is good and very uniform and a degraded BF made it almost useless. The replacement BF also totally cured the problems I had with front ERFs ...

CaK discs and prom are absolutely fantastic. May you remind me of your setup for the last two images ?

Fantastic animaton Alexandra. NLC appeared as far as south as northern Italy this year but I did not take pictures.

Thanks, Franco, very interesting.

Superb CaK images, Mark, at full res they are really impressive

Hi Brian no, based on my experience there is no enough light for imaging in H alpha with a deluminized mirror. However the field is not completely dark, at least with my Quark, may be something can be done at low resolution but in my opinion is not worth the effort. I have no experience with Lunt Ca...

Hi Franco, choose a white mount, not a black one that under the Sun makes the tube hot. That said there are lot of mounts you can consider as an upgrade. I am currently using a Vixen SXD2 but I understand is beyond your price range. Had experience with older HEQ5 and EQ6, all fine for solar observin...

Astrophil wrote: ↑

Sat May 18, 2019 5:56 pm

There are yellow glass, red glass, Baader D-ERF, and Aries D-ERF that I'm aware of.

I am aware too there are all these ERFs, which ones were the subject of your test ?

As with the feeling of others I would not recommend this modification in this way at all. A full aperture ERF is the best solution at these apertures. I totally agree, Mark, however Astrophil's experiment raises an interesting point as it seems that front ERFs can be quite different each other. How...

Now I'm curious...

this is the actual color of the glass