Alternative focal reduce/field flattener?

[BobInYorkshire]

I have a Skywatcher 100ED-Pro with the Skywatcher 0.85 focal reducer.

Are there any others available below 0.85 magnification.

I’ve been on Google but I’m a relative newbie and can’t seem to find any information and if there are will one give me a wider fov?

[Clarkey]

Assuming you are using this for imaging, the more you reduce the effective FL the more you will reduce the imaging area. Also, below about 0.8 you will probably struggle to find anything decent. You might be better picking up a second hand ED72 or ED80 with flattener. There is an ED80 with flattener for £350 on ABS now which may be an option? To me £350 for this is a bargain.

[BobInYorkshire]

4 hours ago, Clarkey said:

Assuming you are using this for imaging, the more you reduce the effective FL the more you will reduce the imaging area. Also, below about 0.8 you will probably struggle to find anything decent. You might be better picking up a second hand ED72 or ED80 with flattener. There is an ED80 with flattener for £350 on ABS now which may be an option? To me £350 for this is a bargain.

Thanks, that’s tempting but I know I’d end up buying another guide scope, guide cam, etc, etc as I wouldn’t want to strip down one rig to put it on the other if you know what I mean and it would end in divorce or my death. 😁😁

[vlaiv]

4 hours ago, BobInYorkshire said:

I have a Skywatcher 100ED-Pro with the Skywatcher 0.85 focal reducer.

Are there any others available below 0.85 magnification.

I’ve been on Google but I’m a relative newbie and can’t seem to find any information and if there are will one give me a wider fov?

Sell your SW 100ED-Pro and focal reducer and get 100-115 F/7 triplet and matching reducer.

That will have the same effect as getting 0.6-0.7 reducer for SW 100ED.

Alternatively - you might try this for example:

https://www.teleskop-express.de/shop/product_info.php/info/p7943_Long-Perng-2--0-6x-Reducer-and-Corrector-for-APO-Refractor-Telescopes.html

It says it will illuminate and correct up to 30mm, but I'm skeptical. If you have smaller sensor like 4/3" (KAF8300 / ASI1600) or even smaller - 1" (ASI183) - then it should work.

This will make your scope F/5.4, so you'll be imaging with 100mm of aperture at 540mm FL.

If you take 115mm triplet scope (yes, it is 50% more expensive than SW100ED) and pair it with Riccardi FF/FR 0.75 - you'll get 115mm of aperture with 600mm FL - or ~F/5.2 system. It is really down to what FL you want to image at / what FOV and sampling rate you want to achieve).