WO guide scope. WO reducer.

[MARS1960]

I hope you guys can help me out and save me from making more expensive mistakes.

FLO finally have what I have been waiting for (WO ZS 73 II) but I now have a dilemma.

Do I really need to spend an extra £26 on the larger guide scope, or will the little £99 one do the job just as well for my amateur backyard occasional AP?

https://www.firstlightoptics.com/william-optics/william-optics-50mm-slide-base-uniguide-scope-with-125-rotolock.html

https://www.firstlightoptics.com/guide-cameras/william-optics-32mm-slide-base-uniguide-scope.html

Do I have to buy the 1.1 Flattener, or can I save some more and buy the Stellamira 0.8 reducer/flattener for a slightly faster f ratio? will it cause any issues if I can? I just don't want to make any mistakes this time round.

https://www.firstlightoptics.com/reducersflatteners/william-optics-adjustable-flattener-for-zs73.html

https://www.firstlightoptics.com/stellamira-telescopes/stellamira-2-0-8x-reducer-field-flattener-with-m48-adapter.html

Any help greatly appreciated.

 

 

 

[Space Oddities]

There is also a reducer/flattener from William Optics for the ZS73: https://www.firstlightoptics.com/reducersflatteners/william-optics-x08-adjustable-reducer-flattener-for-zs73.html

It's a bit more expensive, but I don't think you can go wrong with it, as it's designed specifically for this scope. Perhaps that optically it's the same as some other reducers, but at least mechanically, it seems unique to WO.

The StellaMira is a generic flattener, you can find many brands selling it and recommending it for similar 70-72mm scopes. So, like all generic products, there's a small risk that it isn't a perfect fit for your scope... But all those telescope aren't radically different, so it might work very well  Perhaps some users can share their experiences!

Alternatively, TS Optics in Germany proposes this 0.8x reducer, that is listed as compatible with their 72mm f/6 scope, which I believe is optically identical to the ZS73... as well as 3 other scopes with similar specs. 

 

Regarding the guide scope, I think a ~30mm is enough at this focal length and amateur usage  I'm using one and it's all I need.

There's also ZWO's 32mm scope that's even a bit cheaper at £89, all metal and very solid. I'm using a similar one that is even cheaper, but it's not in stock at the moment...

https://www.firstlightoptics.com/zwo-accessories/zwo-mini-guide-scope.html

Edited January 14, 2021 by Space Oddities

[MARS1960]

3 minutes ago, Space Oddities said:

There is also a reducer/flattener from William Optics for the ZS73: https://www.firstlightoptics.com/reducersflatteners/william-optics-x08-adjustable-reducer-flattener-for-zs73.html

It's a bit more expensive, but I don't think you can go wrong with it, as it's designed specifically for this scope. Perhaps that optically it's the same as some other reducers, but at least mechanically, it seems unique to WO.

The StellaMira is a generic flattener, you can find many brands selling it and recommending it for similar 70-72mm scopes. So, like all generic products, there's a small risk that it isn't a perfect fit for your scope.

Thanks for the reply.

I'm basically trying to save money, The Stellamira even comes with (needed for me) the M48 DSLR adapter saving an extra £25 on top of the £70 for the WO one or even £120 over the one you mention.

The Stellarmira is definitely a perfect fit, my concern is will the reduction to f4.72 cause any imaging issues with an APS-C regards artefacts etc? I wont be submitting images, It's purely for my own entertainment.

Thanks.

[Space Oddities]

The specs don't list the image circle and sensor sizes that are compatible, however the title does say:

This useful 0.8x Reducer / Field Flattener enables DSLR astrophotography

So I think with an APS-C sensor, you should be fine  APS-C is generally either the upper limit of the image circle, or well within this limit (a lot of flatteners/reducers are designed for full frame cameras)!

 

[MARS1960]

Thanks for your help Pierre.