Focal Reducers - Complete Overview and Function

This video is a complete overview of focal reducers and how they function applying to telescopes. There are many different types of focal reducers and they all effect the way your light is gathered in different ways. A very powerful focal reducer will give you more light, but results in more vignetting. A subtle focal reducer will gather less light but give you less vignetting. There are many aspects to a focal reducer and you will find them all discussed in this complete overview!
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[@melvincoleman8008]

You did a much better job explaining focal reducers than 2 dozen other videos a had to watch. THANKS !!!

[@robbrookes4686]

Dude. You are such a wonderful teacher. I am a 47 year old man in 🇦🇺 and I was schooled…so interesting. I now have so much more interest in the hobby. Exciting

[@milllworks]

Extremely well done for essentially extemporaneous tutorial. You definitely know your subject matter, and that comes thru! I just ordered a 6.3 based on your enlightening video. Thank you.

[@MGR1900]

Celesteon, hire this guy!

[@AstroBlender]

Phaedrus Upshaw That is good to know, thanks, I'll be sure to make the change in my vocabulary!

[@Flightguy69]

Great video! I already know how they work, but those who do not know will and can learn a lot about reducers thanks to your video! I will say I own this scope myself and use the reducer and I also went old school with a Zhumell Z8 8" Newtonian / Dobsonian Telescope. I love them both but I still feel this telescope is my favorite out of the two for various reasons. Anyhow, great video.

[@bobbya8622]

Thanks for this tutorial! I am considering a Nexstar 6SE and am looking at the 6.3 focal reducer and a 2” star diagonal with 2” back plate. Your videos have been very helpful in understanding as much as I can pre-purchase. I currently have a Starsense Explorer DX130, and your video on that was also helpful. I would think there are many advantages of the 6SE over the DX130, but the tripod, advanced Goto, and the greater light-gathering capability of the 6SE definitely appeal to me, along with the smaller size.

[@liveandgrow]

I'm having to re-learn a lot of this stuff and this video was perfect. Thank you!

[@itsfahys]

Excellent Explanation of what a Focal reducer does, and why its important for Astrophotography. Im off to buy one now for my Celestron CPC 800

[@larryhibbitts2099]

Great explanation! I'm using a 130mm NexStar myself, and recently picked up an ASI224MC....I'm thinking I need to grab one of these. I was very impressed with what you were able to get with an Alt-Az mount.

[@antandshell]

Seriously the best description & presentation for a focal reducer i have ever seen. TY

[@AstroBlender]

I am glad you liked it!

[@genefoster8936]

I was thinking about a reducer for my Mak-Cas for visual use. Your presentation showed me I would benefit so thanks.

[@kevinrevallo]

WOW! Just WOW! Slymin -I am impressed... and BLOWN away at the same time - So much to learn at an old age! Nice Job!!

[@AstroBlender]

Kevin Revallo Never to old to learn!

[@FPVandotherprojects]

Thanks, second time in 2 days I'm trying to figure out something and find one of your videos and understand it well now!

[@AstroBlender]

+FPVandotherprojects Haha great! I'm glad you found the content useful, and enjoyed the videos! That is the feedback that I like to hear. I'm constantly trying to make quality videos to help you guys out! :)

[@johnpatterson6205]

Very well explained. Thank you.

[@koolkutz7]

Great overview. I have just purchased the Celestron F6.3 reducer for my Astro-Fi 5" SCT scope. Can't wait to try it out for visuals and later for imaging when my T-Adapter arrives. Here's to clear skies :-)

[@arnsteindale5531]

Hi, I just saw this video today, and thanx for a good "gothrough" and explaining of focal reducers. I have a Takahashi FSQ 106ED with a 0,73 focal reducer, but never used it...but now I`m gonna try it on some dso. Thanx again :)

[@AstroBlender]

Should be awesome! Nice scope!

[@GamjaField]

What a great video. I really enjoyed it! I just bought f6.3 reducer for my 6se, can't wait to try it out.

[@AstroBlender]

Thanks man, you'll love it!

[@haansworsie]

SeriousFox I got a 6SE myself and gonna get the reducer too, excited!! Since this is 6 months ago, could you tell me how the reducer fairs on the 6se please?

[@GamjaField]

Christopher Abnett It works great on 6se. These days I use it for Astrophotography with my Sony A7s.

[@zodiacdoc]

Thank you - I am amazed at how much you know at such a young age.

[@AstroBlender]

Thanks, I appreciate it!

[@larrypatterson3957]

Great video. Thanks for taking the time to show all of us. I appreciate your efforts as well as your information.

[@AstroBlender]

Thanks, no problem at all!

[@baobab68]

Thank you for this informative video. About to drop down the money on the 8SE and had read that this reducer was almost essential.

[@danimedina4969]

Great video! Looking to squeeze the most out of a Celestron 4SE that I want to keep portable, this should help me learn how to image some larger fainter objects! Thanks so much!

[@dilipsharan8699]

Excellent video. Gives a really good understanding of how focal reducers work and enhance images. Also the additional information about vignetting was good to learn about; I'd never really appreciated that aspect.

[@AstroBlender]

+Dilip Sharan I'm glad you liked it! Hopefully I can get a video about Barlow Lenses up soon! Take care!

[@poonambhatia5161]

@@AstroBlender can you please tell me does telescope gives black and white image?

[@friskycrewgerrusty]

wow, thank you for the awesome video, very in depth and answered my questions, thanks bruh, will buy a 6.3 reducer

[@michellepierce678]

Great presentation, just shy of 3 years ago, informative and to he point. I read forums for hours with math equations being tossed back and forth. Just wanted a simple explanation on how it works. You did it. I'm a visual learner so I appreciated the graphics. Thank you for the effort you put into this video, with clean fingernails too, ha ha. PS, yes i did burn ants but that was in the 70"s, now new 'mid life' hobby with astronomy. The stars look like ants. :-) May you continue to have balanced success in life with family, faith and work.

[@AstroBlender]

Haha too funny! Well I am glad that I could help you out Rich! Astronomy is a fantastic hobby to get into (expensive too! :D)

[@pekwalker]

Great video! Thank you very much for the explanation. I hope you make more videos in the future. In the Mountainside picture where the white of the snow is blown out, adjusting the white balance at the camera would help?

[@TheJohn48231]

Thank you for helping a beginner understand focal reducers. Great video 👍

[@starwatcher2001]

Still a useful video six years after you made it. Thanks. Wonder what cool stuff you've done since?

[@kevinwenrick7657]

Old post, but what a great job explaining more than just focal reduction. Loved the diagram showing AFOV, a light bulb came on. Thank you very much.

[@AstroBlender]

You're welcome, I am glad you found it helpful!

[@apchris80]

Brilliant video and exactly what i needed! Thank you for saving the day :)

[@asdf9890]

Learned a lot from your video about focal reducers, thanks.

[@AstroBlender]

***** You're welcome, I'm glad that you were able to learn.

[@nikolagovorko7196]

Fantastic video, thanks for making it!

[@johnmeggers5059]

Excellent explanations. Keep up the good work. For the record, the “g” in “vignetting” is silent. It’s pronounced like “vin-yet”

[@robertbennett6410]

Thank you so much for a easy to understand and super video on this, even though Im a ways from doing any AP.

[@AstroBlender]

You're welcome, I am glad you enjoyed it. Learning is all part of the fun!

[@rrbcap]

Excellent Video. Thanks for taking the time to explain focal reducers. I'm just getting into Astrophotography. Would you recommend a hyperstar setup for taking pictures? I understand it takes the F to 2.0.

[@stardarkroomequipment9495]

Perfect professional video thank you

[@floringherman5874]

Very well explained, very professional too

[@AstroBlender]

Thanks!

[@markwelsh9068]

Nice summary and tutorial bud. Appreciated.

[@jeanvallee9340]

Well done, clear, and easy to follow.

[@AstroBlender]

Thank you!

[@jerrysamuelson1247]

Thank you for the great presentation. Will this f/6.3 reducer also work on the Celestron AVX 8"?

[@alligatorpc]

What a nice video tutorial !! Thanks for sharing.

[@AstroBlender]

Of course! I am glad you liked it!

[@alligatorpc]

I have a CPC800 and i'm kind of new to astronomy. What piece and zoom piece do you recommend to observe planets

[@keithsisk9198]

You did well. Enjoyed the video.

[@Omhra]

Awesome. Thank you for this good tutorial..

[@AstroBlender]

No problem!

[@mikeem09]

Fantastic explanation. Thx for this!

[@AstroBlender]

You're welcome!

[@hammettl]

It’s pronounced “vin yet ing” the g is silent. Thanks for the vid. Keep up the good work!

[@AstroBlender]

Yep, I got creamed for that 6 years ago. haha

[@MichaelSamerski]

I think it's "Vinaigrette". :)

[@tykingcrystal864]

Lol I just got a focal reducer and I thought the same thing when I saw more about it.

[@anandarunakumar6819]

Well done, somewhat works like a wide angle lens. Nice to see that Supernova event with a reduced exposure. I get annoyed with these astro manufacturers when they charge ridiculous $ for an apo lens with a mounting unit. Time to use some lens formula and a cnc to thread a lens 😉.

[@luapynneb3069]

Thx for this well explained easy to follow video mate, as i'v just bought the same F6.3 reducer myself to try some Astro imaging, but before that i'm off to burn some ants. Thx pb

[@AstroBlender]

Hahaha! You're welcome!

[@kylecain6685]

LOL

[@WaterlandFilms]

Great illustration Bro!

[@CB-RADIO-UK]

Great video. Very clear.

[@AstroBlender]

Thanks, appreciate it!

[@ishirafernando7604]

Slymin! Did you use a dslr for your imaging? If so what brand and model? I have a canon 7d and am wondering if it is compattible with a focal reducer

[@chulpitostados]

I saw all the video, very interesting and good explanation. Im about to buy an old C8, you need something else to use 1.25'' ocular with the C8 and the focal reducer ?

[@johanneshainer3460]

Great explanation, by the way what Sensor Size do U use on your Setup?

[@stein3209]

great guide!!

[@dirklehew1824]

Great informative video-I have a question? Why can’t I use the Celestron F/6.3 focal reducer/ flattener with my Evolution 8 EdgeHD? Will it degrade the image since the EdgeHD already corrects the field? I would think it would still brighten the image in visual use and widen the field. Thanks for any advice you can give.

[@SubShift]

great illustration. i want to ask about the image you took with nextar mount using the F reducer which shows the M81. is it one frame 30 second picture? or it's been stacked?

[@quarterhorsetj]

I have a celestron se8 on a standard fork mount. Is it recommended to leave in the reducer (6.3) in all of the time for better viewing? Thankyou so much for your very helpful videos.

[@rogeliocprinci]

Hi...what about using a Steeltrack Focuser with a fecal reducer ?? Thanks great video

[@satyajitbhadraroy7723]

Great video.. 👏👏 One stupid question.. do we need to use a field flattener and/or coma corrector to use focal reducers with f4 newt telescopes ?

[@llamarvasquez1803]

Hello? Is there a way you can put a focal reducer on a skywatcher quattro 8? Thank you very much

[@nazame]

Hie, yr deepsky object images seems very nice, what camera did you used? tq

[@bosoxspider1]

Great video. Sorry if i missed it, but what camera did you use for theses photos?

[@michaelkuhn8929]

Great presentation. Question. Can i use another filter other than my white light apeture filter to see more of the sun. I have newtonian 1200mm f/9 8 inch. Reflector scope. Not seeing anything exciting. Have eyepieces from 30mm down to 4mm with 2x barlow.

[@Noxveeel]

Great video! Very useful illustration in the beginning of how focal reducer works. I’ve just bought 0.5 focal reducer for my MAK102 and it perfectly works for visual observation, but if I try to use it for photography on my Canon 700d, it seems like I can’t focus and see only circle of light (like when telescope is not focused on star or planet). Did you face something like this? Any ideas how to fix it?

[@doco6186]

How does the addition of a focal reducer change the back-focus distance. Thanks for your response. Stay safe!

[@Joyof...]

thank you, very informative :)

[@AstroBlender]

You're welcome!

[@djsundayrides4869]

Hi I'm getting the 8 ES my first since I was a kid. My Qt is do I need to get a focal reducer if I'm not going to take picture ?

[@stevehershberger5432]

Informative video....nicely done! Could you do one on flat frames? I'm going to start into astrophotography soon.Thanks! :)

[@michaelbennett8847]

Have you tried 2" eye pieces on the 8SE? Better or worse than 1.25?

[@XJarhead360]

Excellent video.

[@AstroBlender]

Thanks!

[@gjman1972]

Hi when you have a minute can you answer this question? The question is when I have my dslr connected to the back of the Nexstar 8se with the focul reducer, the T-adapter, and t ring etc, the 105mm back focus setup, is it possible to zoom in or out somehow or does it just default to the highest magnification possible? Thanks!

[@StargazerFS128]

Great video! I have a CPC 1100, I mainly use it for visual only, I see you mentioned that having a focal reducer for deep space objects is great, my scope is 2800 focal length, would you recommend a 6.3 for deep space visual? Thanks and once again your video is perfect, great info here!

[@AstroBlender]

I really love viewing deep space objects with a focal reducer on. I don't think this model will work for your 11" telescope, but if you can find an appropriate focal reducer, I would recommend it!

[@shortyumpire]

Good job on this vid. I am curious as to whether you are shooting eyepiece projection or focal plane. Will the reducer work with focal plane methods? I am trying to get a larger FOV.

[@AstroBlender]

+shortyumpire Definitely not eyepiece projection. I just have my DSLR inserted onto a T-Adapter, not much more complicated then that! :)

[@kamil2is]

hi, thak you for the review . can i use focal reduser for visual uses not photography? and is it good for terrestrial views?

[@AstroBlender]

The focal reducer is great for visual use. Check out my review of the Celestron f/6.3 reducer. It is great for visual use! You can use it for terrestrial views but it will make everything pretty bright.

[@ahmadaymandabboussi5841]

What eyepiece should I use when attaching the focal reducer ?

[@flaviosdereste]

Congrats for the video! Did you notice vignetting using the reducer?

[@racheltgal]

Thank you

[@ainttakenanyshit]

I am waiting for my 8se to arrive next week and just ordered today a ZWO ASI224mc camera. Both should be here next week. Question please, from an online FOV estimator, the moon's view extends WAY past the camera frame. Since you have/use the same scope, what is you lens configuration to view the moon in it's entirety?? I have bought a "cheaper" alternative, a .5x focal reducer that shows promise, but, the estimated moon view still extends past the cameras frame. Any help with sharing your setup so see a complete moon will be greatly appreciated... Great video, Thanks again.. Hank

[@davidquinn9182]

That was an awesome teaching video. thanks. DQ

[@jakebob2006]

Wonderful presentation. Thank you a whole lot for it. You know your stuff.

[@AstroBlender]

Thanks, I am glad you liked it!

[@IsmaelMartinezPR]

Hello: could you suggest a starter set for a photography DSLR enthusiast that wants to start astro photo but in a lighter budget.

[@leboch65]

Will the metabones speedbooster used for slr imaging do the same. If not whats the different?

[@SteveGeer]

Your awesome. Thanks for the video. I have and Edge HD800. I haven't purchased a focal reducer, but it's next on my list. What type of camera are you using? I am planning on buying a used rebel for telephotography.

[@AstroBlender]

+Steve Geer Hey thanks! Sounds like a good plan. I'm using a Canon T3i! It is a great camera. The T5i is the newest model, so a T2, T2i, T3, or T3i should all be fairly cheap now.

[@dr7asans]

hi.did you get the focal reducer for your edge hd 800 yet?can you tell me what was the result ?did you find it worthy ?I have the Edge HD 1400, and before purchasing one for me, I need your feedback.thank you

[@livebyreason]

Question about visual observing... I understand that viewing any given object will be both brighter and smaller with a FR. However, if the object is brought to the same magnification, there will be essentially no difference in brightness, correct? If so, this statement holds for both diffuse and point source light, correct?

[@johnnysager8899]

I just purchased a f 6.3 reducer for my 12" ACF f10 and hoping for a good result??

[@curtisreynolds7375]

Excellent info. I have just begin trying to image things using different cameras....I'll be using my DSLR for DSO's but I'm looking at using a webcam for solar system objects. I absolutely cannot get the entire moon in the frame, only a small fraction of it. I assume that's largely because of the crop factor of the webcam sensor. Not sure what the actual crop factor is, but it's a very small sensor, coupled with the needed Barlow to get the focal point to the sensor. I'm hoping this will allow me to get the whole moon in the frame. Thank you so much for this info!

[@AstroBlender]

No problem! Have you tried a 4x4 bin on your webcam if possible? That helps, but is difficult. To be completely honest I always use my DSLR to take images of the entire moon. If I want something real close, then it is time for web cam use. The DSLR always gives me superb resolution as well when going for the full moon. I am glad you found the video helpful! Good luck in your astrophotography!

[@curtisreynolds7375]

Heh... it might be moot. I ordered a 6 inch, F/4, 610mm FL astrograph newtonian... no need for barlow and only 610mm FL... that will likely resolve the entire issue. lol

[@jesusgarcia-xj2mz]

Hey man, So I just bought a Celestron starsense 114mm telescope and I’m unable to see nebulas, galaxies and planets. Got any suggestions or which eyepiece should I buy?

[@Odysseuss.]

Good simple explanation.

[@AstroBlender]

Glad you liked it

[@johnsojka8168]

Can I use a Focal Reducer with a the Skywatcher 190mm Mak-Newt? I am not sure where to put the focal reducer in my optical train, so the light comes to focus on my SBIG STF-8300M. Any help would be appreciated. Thank you.

[@bowen2307]

how do I know which reducer will work with my NexStar 4se?

[@yanwan4895]

This can be used on Celestron 127slt ?

[@zygmuntziokowski7877]

Will you get similar results with NexStar 6SE?

[@ssattanen]

Very good video. Very good explained. Thank you.

[@user-ok4ks6ti3f]

What affects can I expect in a 14 in dob? Or is it even needed with all the light it gathers on it own?

[@carlosalbertopalhares748]

Do you use focal reducer to capture planetary nebula? They are so small, like planets, so I think it is unnecessary... Whats do you think about that?

[@TheLordtaiko]

Can you still use a barlow?

[@X_Excelsior]

will this f/6.3 focal reducer work on a Celestron 7 inch Maksutov Cassegrain?

[@zonda2003]

How far is your camera away from the reducer? I am just trying to get an OK image with my Nikon D3100 but with the reducer it is impossible and I know I need to get a CCD. I have a 9.25 SCG. With a 2 inch diagonal it will not focus it is too far away. I have to use the visual back with the T adapter and butt it up to the reducer but the image still sucks.

[@bluename4]

when it's recommend a focal-reducer with a Celestron sc1100 (280mm opening diameter, 2800mm focal length, f/10)?

[@nx7640]

thx

[@jdsgotninelives]

Thanks! :-)

[@AstroBlender]

Sure thing!