Orion 05531 Thin Off-Axis Guider for Astrophotography (Black)

This is a well made OAG and if you have limited back focus it's a great option. Unfortunately it was too small for my Canon 6D and it would cause vignetting. So unless you have a full frame camera I recommend it.

This is a great product. Of note, you'll need a few things to make it work for you. The manual will only tell you that the two cameras need to be equi-distant. That's great, but you really need to know the length of the stalk to the guiding CCD chip and then get appropriate spacers for your primary CCD. The 'prism to the 'c-mount' is roughly 1.5 inches. Now, you'll need to figure out from there what spacers you need based on your particular camera setup (and the spacers required) so you can make this work. If you're using a DSLR of some type, you might actually have the right spacer with it to make it work. But, as always, do the math and double check it. Second, the set screws on this thing are flimsy! I took it with me to a hardware store and purchased multiple (2 required) 4-40 x 3/8" socket head screws. Just undo the set screws for the 'stalk' and replace them with this. It'll let you screw them down significantly more and keep it stable. Otherwise, once you get the spacing correct and the set screws replaced, this thing is actually a very good OAG.

the prism fell out during the first use and had to be sent for a replacement. the new one works, but some of the craftsmanship could still be better.

I have purchased many Orion products in the past so I was quite surprised by the poor component fit of this device. I feel compelled to warn purchasers about the issues I discovered. The Canon T adapter tangs are much too thin to properly mount a Canon camera body. The camera flops around on the mount which is unusable. I compared this to tangs on my Orion T adapter (which works) and the good ones were twice the thickness. (So Orion cannot maintain common dimensions across their own product line.) I made spacer tabs from electrical tape which made the camera junction usable. Then I discovered that the guide camera junction is also malformed and allows the guide camera to flop around as well. I placed a tape spacer on the periscope tube which was machined too small for its opening. The set screw only clamps the tube in one axis and frees to swivel the camera loosely in the other axis. A third issue is that the supplied extension tube at 1" is much too long to match the Orion Starshoot with a Canon DLSR FL. I happened to have a 1/2" extension tube and ground it down to ~3/8" in order to get both cameras in focus. I would have expected to do this anyway but the Orion description implies that this unit will fit a Canon DLSR camera and Starshoot together when that is not the case at all. It took 5 hours in the workshop to get this product to actually do what it was intended for. That is, hold a Canon DLSR and an Orion Starshoot together in good mechanical connection with a 2" nosepiece. A purchaser without mechanical skills or time to correct this item will be seriously disappointed with its performance out of the box.

This is a very nice piece, excellent if you don't want to add more weight to your mount.,It helps to keep you away from your weigh limit.,.it also comes with all necessary attachments for your camera and optical tube., buy it!

This OAG is the [perfect] solution for back focus constraints when using DSLRs with focal reducers, newtonian, etc. Simple issue with focal reducers, is that they are built to a specific back focus distance of about 55mm. This is made to attach a DSLR directly to the focal reducer. The secret to this OAG is that the canon era adapter is zero clearance to the body of the OAG, and the body of the OAG is the same thickness as a typical T adapter, so using this OAG is SAME back focus distance as a standard T adapter! I can use this transparently with my SCT prime focus adapter (celestron), Lepus Focal Reducer, and focal reducer for my Refractor, simply in place of the T adapter (for Canon). would be nice if they had one for Nikons. Only gave it 4 stars, due to concerns with the other reviewers, as to fitment and set screws. Will revisit and update after I get some hands on, but wanted to make it known the key point, is that this is an exact replacement for a t adapter in depth of back focus.

I have bought probably 500 items on Amazon and this is the first time I have ever felt the need to write a review. As an engineer, this is an absolute horrible design. The two thumb screws that hold the OAG to the adapter that lets it rotate are horrible. You cannot get a sufficient hold to keep your imaging train from flopping around and causing severe tilt in your image. I ended up having to epoxy this piece on to make this usable. I would not recommend anyone get this OAG.

Works great on my C11 and canon dslr. It is extremely light and well built.

Mal concu pour le serrage des bagues. la tete des deux vis n'est pas conique et ne serre pas bien. Failli faire tomber ma CCD astro. Remplacé les deux vis par tete conique. Sinon mecanique tres light. pas serrieux si ce n'est un prix bas. J'ai adapté et gardé mais pas confiance. ne reprendrai pas le meme.

It is a pretty versatile little unit and has tons of adapters so you can make it work with your setup. It took me quite a long time to make it work, but I did get it to work great in the end. The reason I didn't give it 5 stars is that the prism has a very small crack in it (which was there when it arrived). This does not appear to affect the image or guiding yet, but it worries me that it may not last. The screws holding the camera to the OAG are a little bit flimsy which worries me too. Overall held up great for my first trial run imaging with it and worked great with my edgeHD 8" celestron scope

Este OAG funciona pero tardé una semana en encontrar los adaptadores necesarios para que la cámara guía y la DSLR tuvieran foco las dos a la distancia correcta. Con unos 150 euros extra el sistema me funciona en el Celestron Edge HD 8" con reductor de focal.

The basic unit is optically very short at 10.5mm. It comes with a good range of adaptors allowing both M48x0.75 and M42x0.75 on the telescope and main camera sides, with M42x0.75 and C threads on the guide camera side. There are other options such as 2" nosepiece on the telescope side and Canon bayonet on the main camera side. I have used it on an Edge HD8 with 0.7 reducer with an SX Ultrastar guide camera binned 2x2 for extra sensitivity and it has always found a guide star in PHD2. Initially I used it with a ZWO helical focuser to find the guider focus point, but since have replaced that with fully screwed extensions for extra stability. The Orion OAG has four setscrews for locating the prism, but I left these at their factory setting. Moving these might affect the stability so I didn't use them for adjustment. This has proved a much more stable unit than the ZWO OAG v2 that I also tried. I noted the many reviewers who have had problems with this unit in the past, but maybe the manufacturing quality has improved. Anyway, I am very pleased I bought it.

the item is what I expecfed. Thanks