- Brand: ZWO - Model Name: ZWO FF130/FF107 APO Reducer - Accessories: With original box Thank you for viewing. I used this with an FF107, but I'm selling the reducer because I'm getting rid of the telescope itself. This reducer reduces the focal length by 0.7x, making the FF107 faster at F4.9. The best thing about it is its speed. The brightness of F4.9 with a scope over 10cm was powerful. On the other hand, compared to not using a reducer, there will be some aberrations and distortion of stars at the edges of the image. Therefore, if you use it for astrophotography, it's best to correct the images using software like Stellarium or PixInsight. I've attached photos of the Omega Nebula and Markarian's Chain taken this spring with the FF107 and this reducer. The last photo is a cropped section of NGC4438. All images were processed with PixInsight. The camera was an ASI2600MCPro, with 2 hours of exposure for Omega and 3.5 hours for Markarian's Chain. The equatorial mount was an AM3. I've only used it once, so it's almost like new, but it is a used item, so please consider this before purchasing.