Telescope: Bahtinov Focus Trick Is Almost Magic!

[@DavidRice111]

I've seen several vids on how to USE the mask, but yours is the first to include HOW the mask works. Great tutorial, thanks!

[@reflactor]

Thanks you for the kind words. I'm glad it was helpful!

[@almorassi]

Thanks for the video. The explanation was perfect. I printed one and I'm already using it.

[@reflactor]

I'm glad it was helpful. I use my Bahtinov mask all the time. Clear skies!

[@brandtdetering8486]

You've explained this very well. Thank you for sharing the backstory and science.

[@reflactor]

Thank you for watching! I'm finding these research/history videos are fun to make. Clear skies!

[@petset77]

I've seen these, but thought they were strictly a photography device. Thanks for sharing, and kudos to Bahtinov for not being greedy and patenting (similar Volvo and seatbelt tech decades ago). ...these are under $20 on ebay (December 2022), a few more bucks via Amazon. Almost twice the price for the "Orion" version for 8" Newtonians.

[@reflactor]

I was in the same boat. I went waaaaay too long before realizing how useful Bahtinov masks can be even for non-photography. Clear skies!

[@txdave2]

I am glad I stumbled on your channel. I'm a newbie to astronomy. You do a good job of explaining things in a succinct and easily understandable manner, which is very helpful. I bought a Skywatcher 102mm refractor as my first scope. Having a lot of fun learning my way around the central Texas night sky.

[@reflactor]

Hello fellow Texan! I'm still learning lots of new stuff and enjoy sharing when I can. We're just within the band of totality by Fort Worth. Sounds like you might be right in the thick of totality! Have a great eclipse day!

[@JoeJaguar]

great video friend iam sure it will helps alot people. Joe

[@marcoa.rosado4724]

Very well explained 👏

[@reflactor]

Thanks! When I learned about these, I felt the urge to spread the word. Clear skies!

[@_stardust62]

I got one off ebay pretty cheap for my 90mm refractor...works just as you demonstrated! 👍

[@reflactor]

I'm glad they are getting more affordable. Have fun with it. Clear skies!

[@toddkronenberg4126]

Great video. Just ordered a telescope that comes with a bahtinov mask but I had no clue how it would actually work.

[@reflactor]

Congrats on the new telescope! I use the Bahtinov mask quite a bit. It's almost like some kind of analog video game, lol. Clear skies!

[@Harutjun]

Hmm interesting, thanks for this information

[@reflactor]

Thanks for watching. Glad it was helpful.

[@betelgeuse1421]

Really helpful

[@Ab20222]

Are you familiar with the Tri-Bahtinov mask and could you show us how to adjust the mirrors with it?

[@reflactor]

Hmmmm, I am not familiar with that. You have piqued my curiosity though, and now I will spiral down the research hole, lol. Clear skies!

[@joey1317]

Thanks for explaining this really well! I’m new to astrophotography. I’ve just brought a canon 4000D camera with a tripod.

[@reflactor]

Happy to help! I use it all the time whenever I take astrophotography images, whether that be with cellphone or anything fancier. Clear skies!

[@EvenTheDogAgrees]

If you're new to the scene, another great KZbinr you may want to check out is Nebula Photos. He has some great astrophotography tutorials, including the processing of your pictures on the computer (stacking, post-processing). If you're on a budget, he even has a workflow that uses only free and open source software (Siril for stacking and Gimp as a Photoshop alternative). He has one video in particular that might be of interest to you with your current setup, on capturing the Andromeda Galaxy using nothing but a camera, lens, and tripod. You may also look up the 500 rule (simple to calculate) or the NPF rule (slightly more complex) to calculate your shutter speed to prevent star trailing. Btw, @reflactor, I hope you don't mind me pointing your viewers towards other interesting channels as well. That's not to detract in any way from your efforts, but different channels focus on some topics you don't cover on here, or treat them in more detail.

[@BariumCobaltNitrog3n]

18 hours is 6.5 kWh at $0.16/kWh (avg) or $1.29. The Ender 3 runs at either 260 or 360 watts depending on the moon phase. YMMV. Also cost of a patent is about $56,000 so Mr. Bahtinov was wise to give this away. And nice, that's more important than money.

[@reflactor]

I appreciate your calculation!

[@factChecker01]

Fascinating

[@reflactor]

Kindof neat to see a concept from science class put to use in a tool I never knew existed, lol.

[@ADF_Cable]

Thankyou for another ripper video! I've (now) got a GSO 10 inch; I'll have to try the print on my ender3 (in parts though, lol)!

[@reflactor]

My Creality 10 was barely big enough to print the mask for my Orion XT8. Hopefully the Enter3 is big enough for you. Enjoy!

[@dedskin1]

hey man you have diffraction spikes from your spider , its the same thing

[@riparianlife97701]

Not all heroes wear capes.

[@reflactor]

I'm finding more and more heroes in this hobby of astronomy.

[@riparianlife97701]

@@reflactor Boris and Natasha Bahtinov were villains, when I was a kid.

[@reflactor]

Haha, I didn't know that was their last name!

[@riparianlife97701]

@@reflactor Well, technically, Badinov.

[@ronaldsimpson4963]

At 0:30 the shadow of the secondary is off center. Collimation need a tweek?

[@reflactor]

Nope. It's collimated. My smartphone adapter was off-center and Jupiter wasn't centered. Just an unfortunate combination. :(

[@rafaelcosta6757]

If the telescope ins't collimated the bahtinov mask will work normally? I done my best to collimate an old telescope that I have, but the stars and planet still have a halo of light around them, I'm searching something that help 🤣

[@reflactor]

Good question. I honestly don't know, but I would suspect it would work well even if slightly out of collimation. If you're seeing a halo effect, I would guess that's either condensation (should clear up in about 30 to 45 minutes) or an extreme coating of dust. When you look at the mirror, does it look clean? Is the secondary mirror nice and shiny too?

[@rafaelcosta6757]

@@reflactor The secondary mirror is alright, but the primary have a LOT of scretches (it is a very old and bad cared telescope). I though about condensation and dust, but now I'm thinking the problem is the screatches.

[@reflactor]

@@rafaelcosta6757 Those scratches may just be spider webs, etc. I would first recommend cleaning the mirror (see my video on how to do that). If that doesn't fix it up, you can always get it recoated. Costs for that service vary by size.

[@rafaelcosta6757]

@@reflactor Ok, thanks for the attention. I saw you have a series of videos restoring an old and damaged telescope, maybe that can help too, I'll watch them, thanks!

[@reflactor]

@@rafaelcosta6757 Yes, in the second video in that series, I show how to wash a mirror.

[@krazyhorse448]

I got a question that has been recently brought to my attention. My perfect focus isn't anyone else perfect, being I had bad eyes since early childhood and I wear contact lens and have been for 45 years, yeah I'm old. My daughter looking thru my 8 Dob said this is clear to you huh? So I taught her to use the scope and it has the fine tuning extra knob and she said this is perfect for me and it was Saturn and it was tan blob. Sorry for the long intro but do you see having a Bahtinov Mask would make things better for us? Or will it just put things into the range of the fine tuning knob?

[@krazyhorse448]

I post things I look at on my own YT but I use a cellphone and my daughter said it's not in focus the way I see it on the scope, and looking back I agree, it looked way better contrast visually and then I add the cellphone either my old S9+ or my S23 and I always go it was better thru the scope. I hopefully gave you a new topic and enjoy your channel. BTW I'm the old guy at 2AM saying Cheese so it takes a picture so not to disturb the scope. I bet the neighbors are well, There he goes again praying for Cheese again.

[@reflactor]

The Bahtinov mask should get you close. But you hit the nail on the head. One person's "focus point" is going to be slightly different than the next. With binoculars I have to do separate adjustments for each eye (my left is worse than my right). Adjustment is also needed when you add the smartphone camera. I have to usually adjust the focus know even if I don't change anything between using the eyepiece alone and adding the smartphone camera. As far as S9+ camera versus eyeball, the eyball always seems sharper. At least for stills. If I use the pro-video mode, that seems to capture the sharpness well. Saying Cheese works well, but I really like he Bluetooth shutter button these days.

[@krazyhorse448]

@@reflactor May I show mine? kzbin.infospX4DKwUGE0

[@krazyhorse448]

@@reflactor I'm left eye dormant. I test how well my right eye can see this and it's a blur. Ed Ting says keep both eyes open, why? If this eye sees more than why?

[@krazyhorse448]

My daughter also got me S23+ and it's camera is sideways compared to S9, Does one really do better?

[@fatitankeris6327]

I won't be surprised if some company patents it eventually for profit...

[@reflactor]

They might try, I don't doubt that. However, the existing "prior art" is pretty extensive, so they'd need to luck out and get a very naive patent clerk at the USPTO to approve it.

[@Mr123tallpaul]

Yet! Lol

[@reflactor]

Haha, I'm still waiting - no sponsors yet. :)

[@fwpcbuilder3454]

Witchcraft

[@grahamwhite-r6q]

Wwwwww