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Hi Jonfinn64,

You can focus using the camera's LCD in live view mode if the object you wish to image is bright enough. You may have to jack up the ISO and shutter speed. However it will usually be the case that you will not be able to see the object you want to image on the camera's screen. In this case you can use the NexStar hand controller's "Precise Goto" feature that will find a bright star closest to the object you select automatically and then slew back to the object. Although I have not used your camera I am sure it will have a feature to magnify the view on the LCD screen to better adjust focus. Two accessories that will help further are a "Bahtinov Mask" and an angled view finder magnifier like Viewfinder Magnifier though I found this latter less useful.

Good luck!

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Hi Jon,

Welcome to SGL from the West Coast.

You will probably need to get some extension components to account for the removal of the diagonal.

See this link: -

https://stargazerslounge.com/topic/55254-astro-imaging-noob-questions-for-nexstar-8se/

I fear you will struggle with that telescope due to it's very long focal length which will mean much longer exposures will be needed.

Hope this helps.

Good luck and clear skies.

Sandy.

 

 

Edited by Lonestar70
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19 minutes ago, Lonestar70 said:

Hi Jon,

Welcome to SGL from the West Coast.

You will probably need to get some extension components to account for the removal of the diagonal.

See this link: -

https://stargazerslounge.com/topic/55254-astro-imaging-noob-questions-for-nexstar-8se/

I fear you will struggle with that telescope due to it's very long focal length which will mean much longer exposures will be needed.

Hope this helps.

Good luck and clear skies.

Sandy.

 

 

The Celestron f6.3 focal reducer is probably and essential accessory in this regard.

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For a simple software-program of the Bahtinov Mask, this may be of some help:

https://davesastrotools.weebly.com/bahtinov-mask-guide.html

And a few other good & FREE programs from this gentleman:

https://davesastrotools.weebly.com/download.html

I hope you can have some use for these.

And welcome to SGL - it's good of you to join us here!

Starry Skies,

Dave

 

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I, too, would strongly recommend a Bahtinov mask for focussing.

Your mount tracks but not equatorially, so it is not intended for AP, nor is it very suitable. The official answer to this problem is to mount it on an equatorial wedge but before you do that I'd take a break for a re-think. My advice would be that it's worth a dabble with the kit you have, plus a few adapters, but it would not be a good investment to try to rig out this scope for deep sly DSLR imaging. It is unsuitable in other ways as well. If you are going to spend in the hundreds, spend otherwise.

Try the book Making Every Photon Count, by Steve Richards. It's availabe from the site sponsors, FLO.

Olly

Edited by ollypenrice
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You might want to take a look at a piece of software called BackyardNikon.    This should control your camera via USB.  This will help you as there are focus aids, options for taking image sequences and many others.

Another big advantage is that you'll not have to touch the camera when you are imaging, so it'll help reduce camera shake.

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The Celestron SCT T-ring adapter is correct length for back focus requirements. I also have an adjustable length T-tube from Orion that I reach focus in; it's designed for EPP, but can be used for prime. It screws to my T-tube, which fits directly to the rear cell in the same way the visual back does. I use them both in my C6 and Edge 8.  Use Live View; depending on the object's brightness, you may have to adjust the LV screen brightness up in order to see it for focusing. I have to use max on my D3400 for stars at Mag 3-4 or dimmer, and below 6 I can't see them at all. A flip mirror diagonal may help; the camera attaches on the straight tube, and an EP on the vertical, the flip diagonal mounts to the visual back; you obtain focus in the EP, flip up the mirror and shoot a test shot to see if you are parfocal at prime with the camera. If not you adjust the EP depth in its barrel on the flip mirror until what is in focus in the EP is in focus on your test images; as long as you don't shift the diagonal in the visual back or move the EP, you'll be parfocal with both for all following shots. Vixen, Meade, and Orion all make a nice flip mirror. I have the Vixen, it requires a 2" VB. I only use my flip mirror if the object is too dim to see in the LV screen.

A Bahtinov mask is still a good idea. Use a remote shutter release so you don't have to touch the camera, or you'll get blurred shots from movement. Mine uses a ML-3 infrared remote, I think yours uses a wired remote? Live view will also lock your camera's mirror up so it doesn't add vibration.

You won't get perfect shots, but you can get some decent pictures of the Moon, Saturn and Jupiter, enough to see the Galilean moons and Cassini Division, maybe a bit of color. 20-25 seconds at ISO 12800 will give you M13 clearly, beyond that you'll get barrel-shaped stars. 25 sec at ISO 3200 will also give you a little of the nebula in M42 and M43, and some definition in the center. I've also gotten M36 and M103 with single exposures around 25 seconds at ISO 6400. You'll just have to play with exposure time and ISO to get a combination that limits blur from object movement, but gets enough light for an image. Also, the higher your ISO, the more noise you'll get. My times assume tracking and a good polar alignment, and I'm shooting at the native f/10; if you get a 6.3 reducer, you'll be able to trim your exposure time and maybe your ISO a bit. YMMV. Good luck, it's a ton of fun.

Edited by Luna-tic
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