Laboratorium Solaris: Gigantic filaments, arching bridges, hot plages and DMK23

First light again! My TIS DMK23 U274 has arrived. Sometimes this unit shows up in flashy futuristic outfit and prefers to be called Celestron Skyris 274m.

 

Unlike its astronomical sibling, DMK23 comes without cable and nosepiece. I have taken a C-threaded tube that comes with QHY5L-II - fits nicely. USB3.0 cable was a big surprise - very rigid and heavy, it can easily rip out the flimsy camera's USB socket. I was forced to loop it and to attach the loop's base to the telescope's body with Velcro tape. Not elegant at all :(

Once again, PST demonstrated that it was designed as scope for visual observing - the camera reaches the focus when the focus knob runs into its limit, so I'm not sure that it's really a focus position. The image looks satisfactory in this case anyway, so this is disturbing but acceptable.

With the Barlow lens the camera CAN'T reach the focus. I'm using THAT Meade 2x lens :) So I screw out the optical part and just dropped it into the PST's eyepiece port. Focus is now achievable somewhere near the middle of focusing knob travel distance. Unfortunately, it requires 3 panels to capture the full solar disk.

But all above mentioned are minor things compared to the primary benefit: NO! NEWTON'S! RINGS!! :D

 

Software?

SharpCap finds the camera easily but didn't support 12 bit ADC mode. Discarded. FireCapture detected the camera but failed to launch the main screen - new model, nuff said. I had high hopes for this program since it produce 16-bit .ser files that are "edible" for Autostakkert!2. Finally, TIS's own software, IC Capture... Not particualry convinient to use, important functions and dialogues are to be accesed through the main menu, but it's so very fast and "solidly built" - very nice. And when I had stepped on another rake. The data is saved in 16-bit form as "Y16" .avi. The version of AS!2 I was using was unable to open such files. Very bad! With fingers crossed I have opened the file in ImageJ... Yes! ImageJ opened it as a stack of 16-bit frames. I re-saved it as a bunch of TIFFs and AS!2 processed them nicely and properly. But it wasn't very appealing to do such a conversion, especially given the need to process three panels.

Fortunately it appears that while stable release of AS!2 can't do that, the current alpha 2.3.0.21 already supports Y16 encoding. So the middleman was removed.

Today there were too few very weak proms, so the open question remains - what about them? That's a subject for next sunny morning :)

 

Does anyone have pills against logorhea?

 

WARNING! Sun is dangerous, use proper filters for observing and imaging!

 

Aquisition time (start of the session) : JD 2456897.804387 (11:18:19 MSK).

Image orientation: scrambled;

Equipment:

TIS DMK23 U274 via partially disassembled Meade 2x Barlow lens on Coronado PST riding on Celestron CG-4 motorised mount set over Vixen SX half-pier over Vixen SX tabletop tripod on a windowsill.

Aperture 40 mm

Scope's native focal length 400 mm

Effective focal length 800 mm

Tv = 1/4000 s (WOW!)

ISO NA

Gain: --- (something like 19 dB in IC Capture's terms)

Capturing software: TIS IC Caoture;

Exposures: 3x598 (50% used in stacking);

Processing:

1) stacking in AS!2 2.3.0.21alpha;

6) stiching in Microsoft ICE;

7) deconvolution in AstraImage 3 PRO (Richardson-Lucy algorithm, Cauchy type PSF, size 2,1 units, 6 iteartions);

8) high-pass filtering, contrast and brightness adjustment and 0,68x downsampling (bicubic sharper) in Photoshop.

Done