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

Astrophil wrote: ↑

Fri May 17, 2019 7:00 pm

I tested different full aperture energy rejection filters to see how they performed.

what a large difference in T between the hottest and the coldest ERF...

A very interesting experiment indeed, is the hottest ERF you tested still safe at the etalon or would it require additional filtering ?

Green reflection (B600 #0000507). B1200 the same (purchased few months ago).

Beautiful discs, Eric, in spite of the conditions

Really magnificent CaK images, Mark, fantastic

It seems to be a very good unit, Pedro.

Great images, Franco, very sharp!

Fantastic images, Peter, CaK is superlative.

Superb images, Franco, morning hours are always the best for imaging.

Thanks to all of you, much appreciated

At first my Quark wasn't bad, something happened to the BF later... still to understand what...

Great images Brian!

I followed this spot through March and April taking some images while approaching the limb as AR12736 and then during the second and now the third apparition. It is surprising how well the spot survived for all this time, yesterday and today was even surrounded by several pores and tiny spots that w...

Great images and video, Pedro. I am considering to get a Lunt 152 too, seem a very good scope.

Great discs, very sharp and well processed!

Great CaK images, David, nice limb details!

Spectacular animation, well done!

Very sharp image, Bart, spicules, prominence and penumbra filaments came out well. It seems really promising. Just to complete the picture try to see what happens to the other colors, green and red, if they now show spherical aberration and how much.

Great images Alexandra, very sharp in spite of the seeing.