Farpoint FP410 Bahtinov Focus Mask for Celestron 8" SCT

I am giving this 5 stars for great customer service. For some odd reason, the mask was just a pinch too tight on my C8 (a recent model). It would go on, but needed some force, and I was concerned that applying it would knock the scope out of alignment. I contacted the company and they sent a replacement, even though they didn't think it would make a difference. Indeed, it didn't. However, after talking with them further, they agreed that it would make sense to try lightly sanding the inner ring. I did so with a Dremel tool, just going around lightly a few times. That worked a trick. The mask slips right on easily now and works perfectly. Super easy to use!

Read about this method of focusing so I decided to give it a go. The price was low compared to other brands but the mask lives up to its billing. Hard to beat at this low price. The center hole was ever so slightly small to fit over the secondary mirror of my Celestron NexStar 8SE but a little work with sandpaper easily fixed the issue. Focusing is easy and I highly recommend the product.

I struggled to bring my NexStar 8SE in to focus for astrophotography, but this bahtinov mask helps me nail in razor focus every single time, and very quickly to boot! Made out of solid material, the only reason I give it 4 stars is because it doesn't *quite* fit over the "Fastar" plate on my 8SE. As others mention, the inside hole is a little too small, but it doesn't effect the ability to focus.

Had the same fit problem as others. Needed to sand off ~.5mm before it would fit around my secondary mirror.

I should have bought this months ago! Its made of plastic, so just dont drop it on a hard surface as i feel it may crack or break. The adjustment screws that allow you to set quickly onto tube are insulated with a rubber tube as not to scratch the finish of your scope. Dont settle for less.

...to fit around the exterior of the secondary on my 8" Meade SCTdont worry about their not being any washers/clips/screws/retainer of any sort [I was worried, anyways]after some light sanding [100 grit, for maybe 2-3 mins] it started to fit perfectly over the secondary exterior mirror on the front of the SCTworks great. focus achieved w/astro camera. WOOOOT

Useless device - especially for astrophotography. I used it on an 8" Celestron at F10 and found it didn't produce the images it said it would to assist in focusing. I put it in a box and haven't used since. Should have returned it. I think the whole concept for this device is flawed for practical applications.

Just received this product, and it seems nowhere near the right size. I will try to go at it with sandpaper as others have done, but I'm afraid that will make it asymmetrical, and it doesn't change the fact that this product is advertised to fit an 8 inch Celestron SCT, and it does not.

As others have mentioned I had to sand/file the inside a bit to get the mask to fit over my Nexstar 8se secondary mirror, regardless this product does what it is suppose to and is worth a 5 star review. I'll give it a 4 star, considering the simplicity perhaps it could be a bit less expensive.

Does what it was designed for, and does it well, BUT the price is outrageous. $60 for a peace of plastic costing maybe .50 cents.