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

I am using this OAG with a Canon 450D and a Meade DSI Pro monochrome camera as guider on Megrez 72 and also on C8. It focuses on both scopes perfectly and on top of that it also comes into focus with Televue TRF-2008 flattener / reducer when used with C8. I did not notice any vignetting. If you are not able to find the focus, just play with different combinations of extension rings and eventually you will find the right combination.

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.

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!

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.

I have tried using a guide scope to guide but the additional weight and the extra set-up time made it impractical for me, so I decided to get an OAG. I have read reviews saying that Orion was the best for it price so I purchased it. The set-up of this can take a long time, as the instructions really do not help you align your DSLR camera to your scope. I have managed to configure it today. My set-up is a Canon 1000D, and the scope is an Orion 80ED. To get the guide cam (QHY5) to be in focus with camera I used the following set-up: Existing 1.25 focuser on the cope with OAG fitted onto it. I then used the T-Ring to screw directly onto the OAg with no extension tubes. For my camera I used both the 7mm (small) and 18mm (medium, the large is definitely 30mm) (I think) total extension 25mm. Now camera and guide cam are in same focus. I had to use that combo because when I received the OAG both extension tubes were so tight that I couldn't separate them and had to sue them in combo. And it is for this reason I give it 4 stars and not 5 because of how it was delivered. I have not conducted any guiding yet, and my review is purely from a set-up stand point. P.S. I set-up the OAG in daytime be pointing my scope at a chimney stack quite far away.

Nice, wanted to buy the orion guider on the orion website but it was cheaper on amazon which doesn't make any sense, oh well.

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.

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