Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Back to the Future with Fastar

Astrophotography
  • Please log in to reply
5 replies to this topic

#1 Sky King

Sky King

    Ranger 4

  • *****
  • topic starter
  • Posts: 368
  • Joined: 16 Mar 2017
  • Loc: Arizona

Posted 03 March 2021 - 12:49 PM

When I got my 1990's Celestron C8, it came with a rainbow colored sticker that said Fastar, Celestron. Basically Celestron provided the option to remove the secondary lens and replace it with a Fastar lens for camera use, placing the camera in the front of the telescope. Celestron quit making these lenses, but the idea soon developed into Hyperstar and RASA, both popular options. But what of Fastar?  After finding an original Fastar lens, it sat in a drawer for a long time. There were problems. Images using Fastar didn't look great and it was designed for the old ST-237 camera. I tried a DSLR and the the images were distorted. The Canon T21 was not the right chip size.

 

Next up was the ASI224MC, with the Fastar's F/1.95 and focal length of 398. Here are a few examples from last night. Darks and flats in Sharpcap with live stacking and no filter. No post processing. I wanted to show what Fastar and the ASI224MC produced without retouching. Great Scott! 1.21 Gigawatts!?!

 

13 exposures at 60 seconds each for the Crab Nebula 

28 exposures at 60 seconds each for M42

37 exposures at 15 seconds each for the Sombrero

 

 

Stack 13frames 788s Crab
 
 
Stack 28frames 917s M42
 
 
Stack 37frames 542s Sombrero

 


  • PirateMike, Noah4x4, Dynan and 2 others like this

#2 Iamgr8er

Iamgr8er

    Sputnik

  • -----
  • Posts: 47
  • Joined: 28 Nov 2020
  • Loc: Enumclaw WA

Posted 03 March 2021 - 01:17 PM

pretty fun bust in out all the cameras until one worked. one day Ill take some pictures.


  • Sky King likes this

#3 Sky King

Sky King

    Ranger 4

  • *****
  • topic starter
  • Posts: 368
  • Joined: 16 Mar 2017
  • Loc: Arizona

Posted 17 March 2021 - 10:51 PM

In case someone wants to try this, here's the ASI224MC and the original Fastar with 20 and a 21mm spacers.

 

Fastar And ASI224MC

 

 

Also a recent image of the Antennae Galaxies, NGC 4038 and NGC 4039. This was from poor seeing and just 2 second exposures, 279 subs for 560 seconds total. As I explore the limits of this combination the fun never ends! I defocused a star to check collimation and it was very concentric.  

 

 

Stack 279frames 560s Antennae Galaxies

Edited by Sky King, 18 March 2021 - 10:59 AM.

  • acommonsoul likes this

#4 Sky King

Sky King

    Ranger 4

  • *****
  • topic starter
  • Posts: 368
  • Joined: 16 Mar 2017
  • Loc: Arizona

Posted 28 March 2021 - 02:19 PM

Decided to try the ASI533MC, with UHC filter due to the moon and light pollution, C8 and Fastar. Here's the Crab again. I had to crop it as the edges were distorted a little. Unprocessed but rotated to match the previous image. 20 exposures at 32.5 seconds each. The ASI533MC gives 1.64 x 1.64 deg but it's not all useable. With the ASI224MC I get 42.1 x 31.5 arcmin with this setup.

 

 
Crab M1

Edited by Sky King, 28 March 2021 - 05:28 PM.


#5 brlasy1

brlasy1

    Vostok 1

  • *****
  • Posts: 159
  • Joined: 13 Jan 2020
  • Loc: Texas

Posted 28 March 2021 - 02:37 PM

When I got my 1990's Celestron C8, it came with a rainbow colored sticker that said Fastar, Celestron. Basically Celestron provided the option to remove the secondary lens and replace it with a Fastar lens for camera use, placing the camera in the front of the telescope. Celestron quit making these lenses, but the idea soon developed into Hyperstar and RASA, both popular options. But what of Fastar?  After finding an original Fastar lens, it sat in a drawer for a long time. There were problems. Images using Fastar didn't look great and it was designed for the old ST-237 camera. I tried a DSLR and the the images were distorted. The Canon T21 was not the right chip size.

 

Next up was the ASI224MC, with the Fastar's F/1.95 and focal length of 398. Here are a few examples from last night. Darks and flats in Sharpcap with live stacking and no filter. No post processing. I wanted to show what Fastar and the ASI224MC produced without retouching. Great Scott! 1.21 Gigawatts!?!

 

13 exposures at 60 seconds each for the Crab Nebula 

28 exposures at 60 seconds each for M42

37 exposures at 15 seconds each for the Sombrero

 

 

1.21 Gigawatts!  Maybe where you come from, Future Boy...


  • Sky King likes this

#6 Noah4x4

Noah4x4

    Skylab

  • *****
  • Posts: 4,422
  • Joined: 07 Apr 2016
  • Loc: Colchester UK

Posted 28 March 2021 - 02:42 PM

Fastar and Hyperstar are great on large panoramic images like Rosette Nebula, or Horsehead + Flame or M42 + Running Man. I regularly use Hyperstar. However, I combine this with a high resolution camera and a 4K UHD graphics display as Zoom is usually desirable. However, photon capture is incredibly fast. But for galaxies and most Messier objects I find f/6.3 is desirable else they are too small.

But the joy of Fastar SCTs is their versatility giving me options at f/2 (Hyperstar) or f/6.3 (FR) or f/10, or even the latter with Barlow..
  • Sky King likes this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics





Also tagged with one or more of these keywords: Astrophotography



Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics