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Starizona Apex ED with Ritchey-Chrétien

Starizona Apex ED 0.65x L (ApexED-L) Equipment Ritchey-Chrétien
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Average_Astrophotographer avatar
Average_Astrophotographer avatar
I know Starizona says you can use the Apex with an RC scope, and I have seen pictures on here where people have used them.  I would like to hear from those people that have used them,  what kind of experience they have had using this combination, Pros and Cons, and also what size of camera sensor you have used.

Thank you
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Ricardo Pereira avatar
Ricardo Pereira avatar
I’ve used it with an RC10 and a micro 4/3 sensor (asi294mm) and I thought it works great. It makes the scope much faster at f/5.2. finding the correct back spacing wasn’t complicated but it might be more with larger sensors. CS
Anthony Fuller avatar
Anthony Fuller avatar
I have the Starizona long version and used it with a RC TPO, at 308mm  carbon fiber, Truss astrograph, heavy!

The clarity wasn't there but to be fair the RC needed a collimation and the Starizona long version was actually designed for refractors telescopes. 
I have yet to test the setup again, maybe this summer if the weather isn't raining like the last few years here in Atlanta, Georgia. The RC since then has been laser collimated..
Average_Astrophotographer avatar
Average_Astrophotographer avatar
Thank you for the input so far. Ultimately I am not looking for it to be my primary scope but more for the smaller DSO's and galaxies.  I already have the APEX ED-L and was looking to perhaps pick up one of the new CarbonStar RC's but I really don't want to image at f8 or f9. I know it can be done, but living in MN with such few good clear days, and long summer days with only about 5 hours a night the shorter the time to get the data, the better.
David Huff avatar
David Huff avatar
Hello,

I use the APEX ED-L with my TS Optics RC8 and it works great!  You just have to make sure it is collimated without the APEX first to make sure you have an accurate collimation.  The biggest thing I like about it is the fact that it corrects any aberrations in your field resulting in rounder sharper stars.  When paired with either a IMX571 or IMX533 based camera, it reduces the need to bin.  Check out my gallery to see the images I have taken with this accessory.  I also installed a primary mirror decoupler so that I can adjust the image train separately from the telescope.  I purchased from a guy on Cloudy Nights.

CS!
Dave
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Average_Astrophotographer avatar
Average_Astrophotographer avatar
All good information. Nice to hear that it works well up to an APS-C size sensor.  

I'll have to look into the primary mirror decoupler as well.
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Byron Miller avatar
Byron Miller avatar
I didn't use the Apex on an RC, but on an APO, I had to crop a lot because of poor stars on edge and the vignette was strong.  I would not recommend the APS-C or larger sensors unfortunately.  I mean, if you crop al ready because you're focusing on small objects it may not be a problem, but i wouldn't buy an APS-C if that's the case - stick with whatever 4:3rd you may alread have.

for small sensors, it works great.
Rodrigo Roesch avatar
Rodrigo Roesch avatar
The Sarizona reducer works well with 10"RC and 294MC. Here is a picture I took with that setting:

https://astrob.in/e8b017/C/
Average_Astrophotographer avatar
Average_Astrophotographer avatar
Very nice picture
David Huff avatar
David Huff avatar
@Average_Astrophotographer Here is the CN thread discussing the primary mirror decoupler.  The user nateman_doo is the guy who makes these using a CNC mill.  Tell him Dave H. sent you :-)  https://www.cloudynights.com/topic/827768-finally-made-an-rc-collimation-adapter/

This is my latest image I took back in April.  I really think this accessory really helped keep collimation and alignment of my imaging train.
https://www.astrobin.com/1l6dp4/

CS!
Dave
Average_Astrophotographer avatar
Average_Astrophotographer avatar
Thank you for the help with the decoupler. Much appreciated.
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maxbaro avatar
maxbaro avatar
My experience is pretty similar to that of Byron.

APEX-L, RC8, QHY268m (APS-C) and nateman_doo mirror decoupler: unusable, I ended up selling the APEX and switching to a "classic" AP CCDT67 with a back-focus limiting the reduction to 0.75x (hence 1200mm).

With the APEX the field was corrected, however the vignetting was so heavy to make it impossible to be corrected by flats, the dreaded ring of death was evident on most frames.

In the end, after a lot of sweat and swear I came to the conclusion that if you want a fully corrected APS-C field and no crazy post processing you need 48mm elements along all the optical path… the APEX is a merger T2 at camera end… it's simply not enough.

Clearly, your mileage may vary if you like to post-process heavily  or you don't mind strong cropping (that however makes little sense of using a reducer).
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