New Setup for Astrophotography

[Gerry Casa Christiana]

On September 1, 2016 at 12:12, Alan64 said:

Mine came from California, and that's a greater distance I expect.  They generally pack them well, as they had originally made a trip from China.

You'll like that Newtonian.  It's compact for its size, and it will come with a serviceable two-speed focusser for greater focussing control.

You'll need a Cheshire, so order that along with it.  I wish it was available here, as it's one of the best in the world...

https://www.firstlightoptics.com/other-collimation-tools/premium-cheshire-collimating-eyepiece.html

Also, ask if the telescope comes with a collimation-cap.  If not, then get this one, and in addition to the Cheshire...

https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html

Hello

As you have been very helpful I thought I would tell you where I have got to. I finally bought the mount a new EQ6 pro as I thought I had may as well buy a mount that is going to last for a decent amount of time. I also bought the collimator on your advice. They are on their way. I didn't buy a telescope though but I thought I would look and research more as the skywatcher looks good but it didn't really get me that excited so I thought I would research more. I still like the VX8 you mentioned but I'm still looking. 

I guess what I was hoping to do is get a decent size telescope that would be really nice for visual but also for photography. Am I asking too much?

Thanks again for all the advice. I'll be asking for more once the mount comes on the forum to see how to get the perfect polar alignment etc. 

Thanks Gerry

ps sorry can I ask where you are in the world? 

[Alan64]

4 hours ago, Gerry Casa Christiana said:

Hello

As you have been very helpful I thought I would tell you where I have got to. I finally bought the mount a new EQ6 pro as I thought I had may as well buy a mount that is going to last for a decent amount of time. I also bought the collimator on your advice. They are on their way. I didn't buy a telescope though but I thought I would look and research more as the skywatcher looks good but it didn't really get me that excited so I thought I would research more. I still like the VX8 you mentioned but I'm still looking. 

I guess what I was hoping to do is get a decent size telescope that would be really nice for visual but also for photography. Am I asking too much?

Thanks again for all the advice. I'll be asking for more once the mount comes on the forum to see how to get the perfect polar alignment etc. 

Thanks Gerry

ps sorry can I ask where you are in the world? 

Ah, the EQ-6 Pro, eh?  Yes, that should tide you over for quite some time.  Now, it was the VX6, rather, that I had mentioned, although a VX8 would be splendid for visual use, as I have a 200mm f/5 myself.

Ideally, for deep-sky astrophotography, one must think... small telescope, and a LARGE mount.  But one can cheat, just a little.  I think that the EQ-6 and a 150mm f/5 Newtonian might do double-duty, imaging and visual, and perhaps a spot of planetary imaging in addition.  Planetary imaging differs from that of deep-sky, and usually requires a telescope with a longer focal-length.  This is an example of a telescope for planetary imaging...

http://www.teleskop-express.de/shop/product_info.php/info/p2445_TS-6-inch-f-9-Ritchey-Chr-tien-Astrograph---metal-tube.html

...and, if I'm not mistaken, also for close-up shots of galaxies.  But I am not recommending that one for your purposes, as it's only for planetary, really, and only for the telling.

I live just 25 miles south of Memphis, Tennessee, in the state of Mississippi.  Here's an image of the light-dome of Memphis, in the distance, and taken from just outside the north door of my home...

[Gerry Casa Christiana]

On September 8, 2016 at 22:18, Alan64 said:

Ah, the EQ-6 Pro, eh?  Yes, that should tide you over for quite some time.  Now, it was the VX6, rather, that I had mentioned, although a VX8 would be splendid for visual use, as I have a 200mm f/5 myself.

Ideally, for deep-sky astrophotography, one must think... small telescope, and a LARGE mount.  But one can cheat, just a little.  I think that the EQ-6 and a 150mm f/5 Newtonian might do double-duty, imaging and visual, and perhaps a spot of planetary imaging in addition.  Planetary imaging differs from that of deep-sky, and usually requires a telescope with a longer focal-length.  This is an example of a telescope for planetary imaging...

http://www.teleskop-express.de/shop/product_info.php/info/p2445_TS-6-inch-f-9-Ritchey-Chr-tien-Astrograph---metal-tube.html

...and, if I'm not mistaken, also for close-up shots of galaxies.  But I am not recommending that one for your purposes, as it's only for planetary, really, and only for the telling.

I live just 25 miles south of Memphis, Tennessee, in the state of Mississippi.  Here's an image of the light-dome of Memphis, in the distance, and taken from just outside the north door of my home...

Hello again

Can I ask your advice on something as you seem to know a lot of technical things and I don't want to make a mistake. 

I have still not decided on a telescope! I'm considering this one but is the focal length too short but it seems to make some nice deep sky opjects but I do not know how it's going to be for magnification. When you photograph is there a way of increasing the magnification or are you limited by the scope focal length. I'm still unsure whether to go reflector or refractor route. 

http://shop.tecnosky.it/Articolo.asp?SessionID=4DB1DC53-1C3C-4668-A3CB-FFB7BB6825C8&GetInfo=TK70ED&AddScore=TK70ED&Score=1

These are some of the images it's producing. 

https://www.astrobin.com/gear/1101/tecnosky-apo-70420/

Would I making a mistake by going for this over say a skywatcher 150pds?

Its my first telescope so I would like it for imaging but also to use it for visual too. 

I'm also looking at this C8 https://www.ebay.it/itm/162202846440 

So I'm told they are also very versatile for both visual and imaging with a focal reducer  

Sorry to ask all these questions but I like the way you explain things because like you I like the details. My brain works like that!

Many Thanks

 

Gerry

 

 

[Louis D]

You can always increase the magnification using either a regular barlow or telecentric barlow.  However, you're mostly going to be limited by the 70mm aperture.  Figure on a maximum magnification of around 120x to 140x.  In addition, if you use a small chip webcam type of camera where you grab hundreds (thousands?) of quick frames and stack them, the object will look much larger than if a full frame DSLR were used.

The C8 would probably do much better on planets and planetary nebulae because of its much larger aperture and longer native focal length, but poorer on large nebulae even with a focal reducer/field flattener unless many frames are stitched together into a mosaic.

There's no one scope that's best for all objects.

[Alan64]

17 hours ago, Gerry Casa Christiana said:

Hello again

Can I ask your advice on something as you seem to know a lot of technical things and I don't want to make a mistake. 

I have still not decided on a telescope! I'm considering this one but is the focal length too short but it seems to make some nice deep sky opjects but I do not know how it's going to be for magnification. When you photograph is there a way of increasing the magnification or are you limited by the scope focal length. I'm still unsure whether to go reflector or refractor route. 

http://shop.tecnosky.it/Articolo.asp?SessionID=4DB1DC53-1C3C-4668-A3CB-FFB7BB6825C8&GetInfo=TK70ED&AddScore=TK70ED&Score=1

These are some of the images it's producing. 

https://www.astrobin.com/gear/1101/tecnosky-apo-70420/

Would I making a mistake by going for this over say a skywatcher 150pds?

Its my first telescope so I would like it for imaging but also to use it for visual too. 

I'm also looking at this C8 https://www.ebay.it/itm/162202846440 

So I'm told they are also very versatile for both visual and imaging with a focal reducer  

Sorry to ask all these questions but I like the way you explain things because like you I like the details. My brain works like that!

Many Thanks

 

Gerry

 

 

That refractor would be an ideal for deep-sky astrophotography, but the aperture is a bit small for visual use with eyepieces; that is, compared to  a 130mm or 150mm Newtonian.  However, with a 3x barlow and a 9mm ocular, you could realise 140x with it, and that would be about the maximum for a 70mm aperture, if not slightly over its capability.  The images at 140x might be pretty dim, and somewhat soft, though.  120x maximum might be better on most nights, given the dynamics of the atmosphere.  Many people observe with 60mm and 70mm refractors, but they're usually longer in focal-length; for example, a 60mm f/11...

http://www.astromart.com/images/classifieds/874000-874999/874864-1.jpg

...and a 70mm f/10...

http://www.us.all.biz/img/us/catalog/152675.jpeg

Note the lengths of the optical-tubes; hence, their focal-lengths.

However, with 2x and 3x barlows, a 70mm f/6 may still perform just as capably, if not as ergonomically in so far as having to integrate an extra component into the optical train.

[Gerry Casa Christiana]

On September 20, 2016 at 08:04, Alan64 said:

That refractor would be an ideal for deep-sky astrophotography, but the aperture is a bit small for visual use with eyepieces; that is, compared to  a 130mm or 150mm Newtonian.  However, with a 3x barlow and a 9mm ocular, you could realise 140x with it, and that would be about the maximum for a 70mm aperture, if not slightly over its capability.  The images at 140x might be pretty dim, and somewhat soft, though.  120x maximum might be better on most nights, given the dynamics of the atmosphere.  Many people observe with 60mm and 70mm refractors, but they're usually longer in focal-length; for example, a 60mm f/11...

http://www.astromart.com/images/classifieds/874000-874999/874864-1.jpg

...and a 70mm f/10...

http://www.us.all.biz/img/us/catalog/152675.jpeg

Note the lengths of the optical-tubes; hence, their focal-lengths.

However, with 2x and 3x barlows, a 70mm f/6 may still perform just as capably, if not as ergonomically in so far as having to integrate an extra component into the optical train.

Thanks for all your help. I'm the happy owner of a star watcher 150/750 pds. I'm just learning now accurate polar alignment and enjoying it very much. I hope to send my results soon even though I'm missing a lot of equipment. Coma corrector for one but slowly I hope it will all come. 

Thanks again for all your help. 

 

[Alan64]

Visual will be best at first, then to pursue imaging in future with a smaller refractor.

[Gerry Casa Christiana]

On 19/09/2016 at 17:51, Louis D said:

You can always increase the magnification using either a regular barlow or telecentric barlow.  However, you're mostly going to be limited by the 70mm aperture.  Figure on a maximum magnification of around 120x to 140x.  In addition, if you use a small chip webcam type of camera where you grab hundreds (thousands?) of quick frames and stack them, the object will look much larger than if a full frame DSLR were used.

The C8 would probably do much better on planets and planetary nebulae because of its much larger aperture and longer native focal length, but poorer on large nebulae even with a focal reducer/field flattener unless many frames are stitched together into a mosaic.

There's no one scope that's best for all objects.

Hi 

As you helped me so much I wanted you to see my first picture on the mount. 

http://www.astrobin.com/full/271950/0/?nc=user

 

Hope you are well. 

 

Gerry

[Louis D]

On 11/12/2016 at 15:46, Gerry Casa Christiana said:

Hi 

As you helped me so much I wanted you to see my first picture on the mount. 

http://www.astrobin.com/full/271950/0/?nc=user

 

Hope you are well. 

 

Gerry

Dang!  That's looks really good.   All I noticed is that you might want to invest in a coma corrector to help keep the stars pinpoint at the edge.  At lower resolutions, you can't even notice it, though.

[Gerry Casa Christiana]

Hi there

i noticed that too but I have a Baader coma corrector. I bought it second hand but it looks optically perfect. 

Could there be another reason? Bad collimation for example? 

 

Thanks

Gerry

[Louis D]

It could be that the CC isn't flattening the field sufficiently.  Stars in the corners of a non-flat field resemble the ones you've got.  It could also be that the spacing needs adjusted slightly to remove every last bit of coma.  If you're happy with the result, I wouldn't sweat it too much.

[Gerry Casa Christiana]

8 hours ago, Louis D said:

It could be that the CC isn't flattening the field sufficiently.  Stars in the corners of a non-flat field resemble the ones you've got.  It could also be that the spacing needs adjusted slightly to remove every last bit of coma.  If you're happy with the result, I wouldn't sweat it too much.

Yes it could be exactly that because I measured last night the distance from the focal plane to the front of the t ring was 53mm so yes spacing could be the issue.

I will try it. 

Many thanks!

Gerry