C11 Hyperstar + ASI178MC-Cool

Sam@ZWO

the pixel size of ASI178MC is small for most scopes but it maybe just fine for F2 Hyperstar

here is some pictures from our tester

High resolution imaging with a Hyperstar F2 system

20151110120136.jpg

20151110120324.jpg

first light M1

M1.jpg

firstc8

Looks nice!

Do you have exposures, gain, darks, flats and guide details...?

When you say pixel size too small for other scopes, does that include c11 at prime focus also, and only F2 Hyperstar wotks?

What happens when pixel size is too small for the scope? Images can not be focused?

riklaunim

firstC8 wrote:
What happens when pixel size is too small for the scope? Images can not be focused?

Resolution is to high - guiding errors can't be corrected, seeings blurs images, exposures time needs to be very high and so on.

firstc8

riklaunim wrote:
firstC8 wrote:What happens when pixel size is too small for the scope? Images can not be focused?

Resolution is to high - guiding errors can't be corrected, seeings blurs images, exposures time needs to be very high and so on.

Thanks for the advice.

So because Hyperstar imaging is often unguided and exposure times are high, 178 works with it naturally?

Is there a camera among the new cooled will work with other scopes as well as Hyperstar?

landbo

Hi.

I have successfully used an inexpensive 0.5 reducer http://www.teleskop-express.de/shop/product_info.php/info/p676_TS-Optics-TSRED051-Focal-reducer-0-5x---1-25-inch-filter-thread.html with ASI120MC, ASI224MC and ASI178MC. Mentioned reducer is also available in a 2 "version for those who wish an such one.

Sam. Perhaps a similar should be to sale at the ZWO page ???

Regards Leif.

firstc8

I was just thinking about this myself.

I have been using the Celestron F6.3 - Scopestuff focuser - 120mc with my C8 so far, but I also have a Scopestuff 1.25" F5 reducer Iike you mentioned above. It can be threaded onto the 120mc nosepiece, I just have not a chance to use it yet.

Is it possible to use both reducers F6.3 - focuser - F5 - 120mc to get lose to Hyperstar range? I will not be surprised if there is vignetting but I also have a small sensor only capture the center of the image anyway.

Should I try this combo?

riklaunim

firstC8 wrote:
So because Hyperstar imaging is often unguided and exposure times are high, 178 works with it naturally?

Is there a camera among the new cooled will work with other scopes as well as Hyperstar?

Hyperstar is a very fast f/2 imaging system which allows using very short exposures. Guiding depends on mount quality. For bigger SCTs it will be rather mandatory.

IMX178 has quite small pixels - 2.4 µm - which give very high resolutions even with hyperstars, and such are very hard to use for DS imaging. I can be done but it's hard.

Landbo wrote:

I have successfully used an inexpensive 0.5 reducer http://www.teleskop-express.de/shop/product_info.php/info/p676_TS-Optics-TSRED051-Focal-reducer-0-5x---1-25-inch-filter-thread.htmlhttp://www.teleskop-express.de/shop/product_info.php/info/p676_TS-Optics-TSRED051-Focal-reducer-0-5x---1-25-inch-filter-thread.html with ASI120MC, ASI224MC and ASI178MC. Mentioned reducer is also available in a 2 "version for those who wish an such one.

Simple focal reducers don't correct the field like dedicated SCT reducer/correctors do. That may pass for small sensor like in those cameras, but that may not always be true.

firstC8 wrote:

Is it possible to use both reducers F6.3 - focuser - F5 - 120mc to get lose to Hyperstar range? I will not be surprised if there is vignetting but I also have a small sensor only capture the center of the image anyway.

Should I try this combo?

With 1/3" diagonal sensors you can use the SCT f/3.3 dedicated reducer/corrector which will be close to f/2 Hyperstar at a fraction of a cost. Other option is to just use small APO refractor. I did some C8/C11 DS images but then moved to 65/420mm APO refractor (small, ~cheaper, stable for DS astrophotography).

firstc8

I could not find anyone carrying f3.3 reducer, so I thought of piggyback f6.3 and f5.

If 178 is difficult for DS imaging, would 224 or 174 be better? They have bigger pixel sizes.

riklaunim

The bigger the easier.

Sam@ZWO

the M1 exposure 30s and 100 frames stacked

more images

M78 150s exposure 28 frames stacked

m78.jpg

NGC891 60s exposure 100 frames stacked

ngc891.jpg

donboy

the M1 exposure 30s and 100 frames stacked

more images

M78 150s exposure 28 frames stacked

What gain setting for these images?

Don

Sam@ZWO

gain is 0 as the 178 has a 14bit ADC

donboy

Sam, what would you suggest for the cooled 224?

Don

Sam@ZWO

donboy wrote:
Sam, what would you suggest for the cooled 224?

Don

Hi Don

there are 3 ways to imaging with 224

1.lucky imaging

2.low gain

3.high gain

just like this review said

https://www.facebook.com/notes/dominique-dierick/testing-a-cooled-zwo-asi-camera/10153861021728968

firstc8

Sam wrote:
donboy wrote:Sam, what would you suggest for the cooled 224?

Don

Hi Don

there are 3 ways to imaging with 224

1.lucky imaging

2.low gain

3.high gain

just like this review said

https://www.facebook.com/notes/dominique-dierick/testing-a-cooled-zwo-asi-camera/10153861021728968

Sam, what scope specs/reducer were used in the above tests?

I also posted a new question to you in my 120mc as guide scope thread.

Thanks!