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IC410 - Tadpoles in mono


swag72

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A stunning image Sara - fantastic detail and really smooth.

I'm intrigued by your use of the C9.25. I have one, which I use for lunar and planetary work with a Baader Steeltrack focuser hung on the back.....and it's a cracker, but I've never tried DSO imaging with it. How did you get on with the spacing from the reducer to the chip? I assume you had an FW and an OAG in there?

 

The reducer spacing is 110mm but mine is at least 123mm. I had to add some extra space to focus the Lodestar. Masses of room for a filter wheel.

I must say I'm well impressed with this. When I started out I had a Meade SCT & quickly got the 80ED before I gave up. Now you've seriously got me thinking again.

Have you done any RGB tests with it Sara?.

 

This is only the first image I've done with this scope. I'm planning on using it for LRGB soon.

Lovely image Sara - looks like you had to work for it but its come very good in the end - colour? wait and see it the weather abates for you (wish it would here)

 

Cheers Francis. I got there in the end!

Fantastic image Sarah! It's wonderful to see the Tadpoles with this detail and magnification, if the OIII matches this you'll have

a superb bi-colour image, no doubt,

E.

Thanks! I hope to get OIII, we'll see!

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@Gav - You may need to think about a mount change for a longer focal length. I'm certain that the HEQ5 will not cope with it. 

Thank you for this little nugget of advice... I have since done a bit more research and unfortunately my Year 1 AP budget doesn't stretch to that scope, or a new mount to accommodate it! I will settle for just enjoying the fruits of your labours for now...

Hope the weather sorts itself out soon.

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Superb image Sara and it gives me hope that my EQ8 will handle the C11 with FR at 1.7M

Not so easy to use a conventional focuser when imaging Olly - the focuser itself eats up an awful lot of that backfocus and when you add in the OAG and filter wheel....  I have a lovely moonlite for my Edge but it doesn't get used for imaging.

For an ordinary SCT this doesn't apply as the focal reducer is behind the focuser, so it moves with the drawtube ,thus maintaining the FR to sensor distance.

The Edge has the flattening elements in the baffle tube, so a focuser will alter the flattener to sensor distance.

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For an ordinary SCT this doesn't apply as the focal reducer is behind the focuser, so it moves with the drawtube ,thus maintaining the FR to sensor distance.

The Edge has the flattening elements in the baffle tube, so a focuser will alter the flattener to sensor distance.

Ah yep - good point, well made!

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 Alternatively you can lock up the mirror and put a conventinal focuser on the back since SCTs have so much back focus.

Olly

I think that only the Edge HDs have mirror locks...the normal XLTs don't. Though i remember reading an article by "Bud" Budzynski (Astronomy Now November 2012) that the later XLTs have the same mirror support as the Edge. He was able to add mirror locks to his C11 fairly easily. It's not for the faint-hearted though....

I am determined to try my C11 on the EQ8 to get more reach. If I could get a result 1/3 as good as Sara's then I'd be very very pleased. I do have a Moonlite on the C11, so focusing shouldn't be a problem. The resolution of 0.53 "/pixel (Atik 428) will probably be a much bigger issue.

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What fantastic resolution on the tadpoles Sara, and binned 2x2 as well. you have done really well using the sct for the first time. I use a C11 and found it to be a real handfull at the begining, but gradually came to terms with it. Regarding the focusing I think problems start to occur when you slew to different parts of the sky due to mirror flop, Though the c925 is'nt as bad as the c11 for this, I also use the moonlite focuser and found it to be brilliant no need to move the mirror any more. i'm really looking forward to galaxy season as this is where the sct's excel so good luck with the new scope. @ zakalwe good memory I saw that article in astronomy now and decided to to do the same mod to my sct, its the best mod I've ever done.

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The reducer spacing is 110mm but mine is at least 123mm. I had to add some extra space to focus the Lodestar. Masses of room for a filter wheel.

Great result, Sara!

Tracking/ guiding looks excellent. Do you know what f/ratio you were getting with that reducer spacing ... and how far you can push it? I used to get to about f/5 or so with my SCT before coma became objectionable, though that was with a rather smaller sensor (11.2mm diagonal).

Adrian

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... 2x2 bin - Magic!!!

Assuming it ever clears up here, I'll give that a bash. Its not looking good...the skies are black again and there's shedloads more rain forecasted.  :mad:  :mad:  :mad: 

What fantastic resolution on the tadpoles Sara, and binned 2x2 as well. you have done really well using the sct for the first time. I use a C11 and found it to be a real handfull at the begining, but gradually came to terms with it. Regarding the focusing I think problems start to occur when you slew to different parts of the sky due to mirror flop, Though the c925 is'nt as bad as the c11 for this, I also use the moonlite focuser and found it to be brilliant no need to move the mirror any more. i'm really looking forward to galaxy season as this is where the sct's excel so good luck with the new scope. @ zakalwe good memory I saw that article in astronomy now and decided to to do the same mod to my sct, its the best mod I've ever done.

I'd be interested in seeing how you get on with this. I have a moonlite on mine with the DC focuser (controlled through a Hitec DC Focus controller). I can't imagine life without it. especiallay for planetary work. There's such a fine line between being in focus and not...the stock focuser would do my head in trying to achieve proper focus. my goal is to use the SCT for galaxy imaging too....if it works then it'd be a nice complement to my Equinox 80 widefield.

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Thanks Adrian. Regarding the spacing and the F ratio, if they are indeed linked beyond the 0.63x stage then at approx 1300mm it should be at about f5.6 I reckon. I don't want to fiddle any more at the moment. It's working and that's good enough :grin:

@Steve - My enemy at the moment is wind, and lots of it :mad:

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Fantastic Sara, your avalon has dealt with the FL superbly.

regarding focusers ;).....

your result is great so it obviously works.

this is all a bit afaik from here.. if anyone can clarify it would be great

SCTs do not have a true fixed F ratio due to the primary mirror moving up and down and the f ratio shifting with the spacing to the secondary, i think the closer the primary is to the secondary the faster the optics, this needs a external focuser to test out and one that allows the reducer to move internally.

much of a muchness as you already have brill results :)

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