Venus with three filters (17/01/2019)

[NenoVento]

Hi all,

Since I don't seem to find the time for going at a higher altitude for capturing Venus, yesterday I tried again from home (located at sea level), this time with the idea of testing a couple of things, such as to use the blue filter (which is the closer thing I've got to an UV-pass).  I started setting up my gear a bit too late, with the planet already past its transit (which was at 15:48), the seeing was of about 1" and there was a bit of wind (15 knots) and some Saharan haze in the atmosphere (locally known as calima):

I apologize for not having the tags in the above picture in English. I made the composition in the gimp when I finished processing the videos, in order to send it to family and friends (you know ho it is like), but forgot to save the file for making an English version as well. Anyhow, I believe it is quite easy to understand: "filtro" is the Spanish word for filter, and the other non English (or made up) words are "Azul" (blue) and "PolVar" for the variable polarizing filter.

The gear:

• Celestron CPC 800 GPS XLT
• ZWO manual filter wheel
• ZWO blue filter
• ZWO IR 850nm Pass filter
• Solomark variable polarizing filter
• GSO 1.25" 2.5x Apochromatic Barlow Lens
• Risingcam GPCMOSS02000KMA (mono camera)
• Risingcam GPCMOS-1200KPC (colour camera)

The software:

ToupSky

I made two minute movies with the following setups:

• Venus blue filter: 19.19 & 0.3ms  
• Venus IR-pass filter: 33.87 & 0.8ms
• Venus no filter: 4.31 & 0.3ms
• Venus variable polarizing filter as closed as possible: 20.64 & 2.0 ms
• Uranus no filter: 31.39 & 99.292 ms 

Autostakkert
RegiStax
Fitswork
The Gimp

As you can see, I didn't get the elusive clouds (although there may be a hint of them in the no-filter picture). Honestly It is very tricky to get a proper focus without the aid of a bahtinov mask. Also, I need to remind myself to check the collimation of my telescope...

Later that night I made my first session using Celestron's CPWI and my gotos got so accurate that I made my first ever picture of Uranus, which you can see at the bottom left of the above image, this time using the colour camara (which I also used for aligning the scope!).

Best regards,

NV

 

[Ibbo!]

Shows the phase very well.

I am also struggling with focus.

My first outing with the UV resulted in nothing as the cloud came just abpout the same time I got Venus on the camera chip.

[NenoVento]

Hi @Ibbo!. It must have been really frustrating I rekon. To help with the focus issue, I've thought about getting one of those feather touch focusers, but in the end I decided for a motorised one which, according to the tracking system, is in its way already 🙂.

Edited January 19, 2020 by NenoVento
Typos

[Ibbo!]

I have a Moonlite on the 8"SCT but the MHP would not connect today so no motor focus.

If i have chance tomorrow I will try with and without the x2.5 powermate if I don't get enough light with the UV I can use the C11 but it is a lot more of a challenge to get it on and off the mount.

[NenoVento]

What an arsenal you have got!. I'd suggest to increase the gain as much as possible before giving up with the barlow... Good luck, I'll be looking forwards to see your results.

NV

Edited January 19, 2020 by NenoVento

[willcastle]

Look great to me! I like the IR filter image best I think

[Pete Presland]

The phase is showing very nicely, well captured and reported.

[NenoVento]

Thanks @willcastle and @Pete Presland. Hopefully I'll get a few more chances before March.

[Ibbo!]

Well it was much brighter without the powermate, but it was still a mess of an image.