Adapters needed for attaching a Canon T3i to a Celestron NexStar 4SE

[Iseden]

Hello!, I recently bought a Celestron NexStar 4SE telescope! My friend, an amateur photographer also recently bought a Canon T3i! We are both very interested in diving into some amateur astrophotography. What we would like to know is what adapters would be necessary for attaching his camera to my telescope? We are interested in capturing the moon, Saturn, and especially deep sky objects such as the Messier objects. Also, what is a "barlow" I've seen the term used before and have no idea in the world what it is. Would a barlow be needed for astrophotgraphy? Thanks!

--- Alex

[AustinPSD]

You need a T-ring (specific to your Canon camera body), and a T-adapter (mostly generic) that mates to back of the 4SE. The latter is threaded on both ends, one end mates to the visual back of the OTA, the other threads into the inboard end of the T-ring. The T-ring has a bayonet adapter that mates to the camera.

With that in mind, the 4SE is a very lightweight alt-az, single-fork mounted scope. It is asking a lot to attach a DSLR to the back of this and expect to get any sort of high performance out of the combination.

A Barlow is a sub-aperture corrector that acts like a tele-extender. It increases the effective focal length of the telescope, which in turn increases magnification (for visual use) of the telescope/eyepiece combination, or increases image scale in the case of imaging. Somtimes a Barlow is used in combination with a web-cam/video imager for planetary imaging, to increase the apparent image size. The usual case with an SCT for most other imaging applications is the opposite - the inherent focal length is too long, so a focal reducer is used to increase the apparent field of view.

You might use the T3i's video mode for planetary imaging, however there are better, less expensive and clumsy solutions based on web-cam/dedicated video imagers.

It is unlikely you will do much DSO imaging with the 4SE and any camera combination - due in part to the alt-az mount, and in part to a number of other factors including the relatively unstable tripod, etc.

The 4SE is basically intended for visual use, not for imaging...

[andyp180]

hi and welcome to the forums.
clear skies,

[sxinias]

Connect a DSLR to a 4SE. Yes, you can do this and will be able to photograph the brighter deep space objects such as contained on the Messier and Caldwell lists. Dim objects like the Horse Head Nebula will be very challenging or impossible dependent upon the conditions at your observing site. You will have many issues to over come and will be limited to very-short, unguided exposures. See the sticky for azimuth mount photography on the astro imaging forum. Here is an example of photographs that the 4SE is capable of doing. Flickr: Sxinias' Photostream

First issue. The 4SE has a focal ratio of f/13; entirely too large (slow) for very-short exposure work. You will need a 0.63 focal reducer which will lower the focal ratio to f/8 ... still slow but workable. 0.63 focal reducers are not exactly a high demand item for small MAKS. If you are going to do photography with one, best is to convert the MAK rear threads to a SCT rear so the photography accessories made for SCTs will work on the MAK.

Fortunately attaching your camera and converting the threads are easily done. Buy the Baader Adapter (2958500). This will convert your rear threads to SCT threads. Get a Meade, Celestron, or Hirsch 0.63 SCT focal reducer. This screws directly onto the Badder adapter. Next get a Celestron visual back which screws directly onto either the Badder adapter or the visual back. This sets up your MAK like a SCT. none of these accessories are expensive.

Get a t ring for your camera and a t ring adapter and you can connect the camera to your telescope.

The last thing to get is either a firing cable or remote shuter with interval timer for your camera. The firing cable will let the mount control the camera. An interval time does the same thing and is easier to use.

The 4 SE must be modified if you are going to use its wedge and operate in the equatorial mode. See the sticky on the nexstar telescope forum.

Good luck and clear skies.

[Iseden]

Baader Adapter 35mm thread to 2' SC (For 4' NexStar + Meade ETX)

Celestron Reducer - Corrector - Accessories

Celestron Visual Back 1.25 - Accessories

Zhumell Mounting T-Ring for Canon EOS Camera - Telescope Accessories at Telescopes

Celestron T-Adapter for NexStar 4SE Telescopes - Telescope Accessories at Telescopes

[sxinias]

The T adapter for the 4SE is designed to screw directly onto the 4SE and will not allow you to use the focal reducer and visual back. You need this T adapter to use the focal reducer with the visual back: Celestron T Camera Adapter Universal 1 1/4 Inch - Telescope Accessories at Telescopes