attaching DSLR to Celestron C6-N

1. It depends on the DSLR but in general I'd think that you could focus but most likely it won't work with any coma corrector.
2. Collimation can only be done with the 3 screws on the secondary holder. The back isn't available for collimation unless you remove the rear cap
3. No.

Thanks again for the reply!! So when I remove the 3 screws on the back, I will gain access to the collimation screws, right?

Presumably, but I have never seen the back without the cover on.

Buyer beware be aware...

I have a C8-N and I might resell it; not because it's bad but because I found out I'm not the type of person to take care of Newtonians and adjust the mirrors and all that. Maybe it's because of my experience; I supposedly collimated the thing with an Orion laser collimator, stuck a plossl in there, pointed to Jupiter and expected to see something amazing or at least inspiring. What I saw was horrifying .

Jupiter was a very bright oval dot like an illuminated egg and had a brownish line running across it, off-center. The stars were all thin short lines on a grayish background. (the gray background was probably due to my location, but it added to the miserable scene)

And I expected to take amazing planetary and DSO photos?  Duh...
Maybe it's my fault, and it probably is, but I I've been noticing a lot of old people (experienced people) end up with a simple refractor. Why? because they cannot handle all this stuff anymore, especially since Newts are heavy.

Maybe I'm just overwhelmed, but this is my opinion. Newtonians are for patient, perseverant people with moderately large muscles (lol) and a moderately large backyard that they own. It also works very nicely with a observatory dome.

FYI here are the cons:
Too heavy for me and my mount
Not easy to maintain
Cheapish focusers. I would need to buy another one for astrophotography
Primary mirrors with clips cause uneven star diffractions and I would need to buy an aperture mask or ring for astrophotography
Too long
Star aberrations and warped field will force me to buy an expensive coma corrector for astrophotography


Pros:
Fast F/5 focal ratio
long 1000mm focal length
cool star diffractions because of spider
dew cannot reach mirrors in most cases

That's basically it.
What do you think?

Buyer beware be aware...

I have a C8-N and I might resell it; not because it's bad but because I found out I'm not the type of person to take care of Newtonians and adjust the mirrors and all that. Maybe it's because of my experience; I supposedly collimated the thing with an Orion laser collimator, stuck a plossl in there, pointed to Jupiter and expected to see something amazing or at least inspiring. What I saw was horrifying .

Jupiter was a very bright oval dot like an illuminated egg and had a brownish line running across it, off-center. The stars were all thin short lines on a grayish background. (the gray background was probably due to my location, but it added to the miserable scene)

And I expected to take amazing planetary and DSO photos?  Duh...
Maybe it's my fault, and it probably is, but I I've been noticing a lot of old people (experienced people) end up with a simple refractor. Why? because they cannot handle all this stuff anymore, especially since Newts are heavy.

Maybe I'm just overwhelmed, but this is my opinion. Newtonians are for patient, perseverant people with moderately large muscles (lol) and a moderately large backyard that they own. It also works very nicely with a observatory dome.

FYI here are the cons:
Too heavy for me and my mount
Not easy to maintain
Cheapish focusers. I would need to buy another one for astrophotography
Primary mirrors with clips cause uneven star diffractions and I would need to buy an aperture mask or ring for astrophotography
Too long
Star aberrations and warped field will force me to buy an expensive coma corrector for astrophotography


Pros:
Fast F/5 focal ratio
long 1000mm focal length
cool star diffractions because of spider
dew cannot reach mirrors in most cases

That's basically it.
What do you think?


​​​​​​

Thanks for your explanations. but if i buy an apo for the same price as a 6 inch newtonian, won't i face such downsides?:

1- Since it has a smaller aperture and focal length, it will collect less light while observing dso and planets. the objects will look small because the focal length is less.

2- For astrophotography, especially since galaxies are small, if I crop, won't the image get distorted?

@Eta_Carinae 
To answer your questions first:
1A. It will collect less light, but it's definitely not incapable for astrophotography. For visual it's a different story, you'll need dark skies for the average refractor to work more visually for DSOs.
1B. Objects will be smaller, but you should always start wide when starting astrophotography then gradually go narrower when you learn and have more experience.

2. If you crop the image, it will not get distorted.


For a petzvel design apo, such as a Redcat 51, you don't need a coma corrector.

You might not find many cheap APO refractors, but you should look on astronomics.com, their astro-tech ED refractors are cheap, and many beginners start out with those (you'll need a flattener also).
Here is a good ED doublet for example https://www.astronomics.com/astro-tech-at72edii-refractor-ota-fpl-53-f-6.html?___SID=U

And here is the flattener for that doublet https://www.astronomics.com/astro-tech-8x-reducer-field-flattener-for-the-60ed-and-72ed-optical-tubes.html
There are no reviews for it which is strange. But you can believe me when I say astro-tech refractors are really good for the price.

If you have a moderate amount of money, you should look at William Optics, they're very good telescopes but also require flatteners (besides the Cat series).

Watch Youtube reviews too, it helps.

Also look at this Astrobackyard page to see if you like any of the refractors it mentions there https://astrobackyard.com/beginner-astrophotography-telescope/#:~:text=The%20Sky%2DWatcher%20EvoStar%2080ED,between%20performance%20and%20price%20point.

Or you can use a Redcat 51 with a star tracker. It will be roughly around $1300. But don't forget the necessary accessories.

Like this https://www.youtube.com/watch?v=YVtl_nZLDoQ

@Eta_Carinae 
To answer your questions first:
1A. It will collect less light, but it's definitely not incapable for astrophotography. For visual it's a different story, you'll need dark skies for the average refractor to work more visually for DSOs.
1B. Objects will be smaller, but you should always start wide when starting astrophotography then gradually go narrower when you learn and have more experience.

2. If you crop the image, it will not get distorted.


For a petzvel design apo, such as a Redcat 51, you don't need a coma corrector.

You might not find many cheap APO refractors, but you should look on astronomics.com, their astro-tech ED refractors are cheap, and many beginners start out with those (you'll need a flattener also).
Here is a good ED doublet for example https://www.astronomics.com/astro-tech-at72edii-refractor-ota-fpl-53-f-6.html?___SID=U

And here is the flattener for that doublet https://www.astronomics.com/astro-tech-8x-reducer-field-flattener-for-the-60ed-and-72ed-optical-tubes.html
There are no reviews for it which is strange. But you can believe me when I say astro-tech refractors are really good for the price.

If you have a moderate amount of money, you should look at William Optics, they're very good telescopes but also require flatteners (besides the Cat series).

Watch Youtube reviews too, it helps.

Also look at this Astrobackyard page to see if you like any of the refractors it mentions there https://astrobackyard.com/beginner-astrophotography-telescope/#:~:text=The%20Sky%2DWatcher%20EvoStar%2080ED,between%20performance%20and%20price%20point.

thank you very much for your suggestions i really don't have a budget to buy an apo and i have little or no access to these apo in my country i hope newtonian will do the job for both observation and ap. Since I already have some Newtonian experience, I don't have much difficulty, do I?

@Eta_Carinae If you believe you're the type of person who can handle Newtonians, go for it. But it's not for me.

@Eta_Carinae If you believe you're the type of person who can handle Newtonians, go for it. But it's not for me.

Thank you for your support and suggestions.

@Eta_Carinae 

Hello Eta, just uploaded to the public area, file too large for posting here..