I just ran across this video and it is the first video I have ever seen that explains what a reducer does. It is the best timing as I am ready to buy a reducer/flattener for my takahashi which is over $1300. You have saved me $500 for a flattener only. Truly faster is not better in this situation especially in this hobby we spend a fortune on equipment then more to reducer quality for speed doesn’t make sense to me either. Again great info and video
Thanks for this. It’s been 3 years now and I was told the same, that the reducer would speed up my imaging by gathering more light. That just never made sense to me, so I found your video and blogspot when trying to understand what was actually going on. Thank you for your explanation.
I know you did this video almost a year ago. Is there anyplace in your various videos or blogs that you show us what you imaging trains are both with and without the reducer it would really help. Great video and very well explained.
Thanks Marvin: Here is a video that shows it th-cam.com/video/35bgXMcXF2Y/w-d-xo.html. Starting at the camera end it is: Camera, EFW, T2-T2 adapter, 11mm ring, M48-T2 16.5mm extender then the Focal Reducer or Field Flattener. the back Focus is 55mm. - Good Luck
AstroQuest1 yeah I was curious as I have a 72mm 420mm focal length refractor and most reducers seem to be 0.8 but larger scopes seem to have a more reduction down to 0.5 or 0.6
@@rogerwilkinson2818 That's right. Some of those larger scope have very long focal lengths (high F-ratios) narrow FOVs. Their pixel ratios tend to be low as well so a FR would be a great benefit in those cases. Your scope has a good FOV already and (F5.8) lowering much further you would be in the camera lens range.
thanks Kurt, I hate dealing with back focus. even with a caliper, it's impossible to get a good measurement. so, for example a 925mm scope would then become a 666mm. now my pixel size and new focal length would make my pixel scale new correct?
Hey Richard, yes it does get quite confusing but adding a FR will change the scale. There is a website, astronomy.tools/, where you can enter your equipment and it will tell you the scale and such. Cheers
Good question Richard, the answer is no. Typically from the the back of a flattener or flattener/reducer it is the same 55mm. Check the manufacture to be sure though. Cheers
"Man Kurt, you just suck!" LOL Probably because you're comparing your outtakes with very 'smooth operators' who never show their multitudinous outtakes. A guy who's not afraid to show his outtakes and realises we'll have a good laugh along with him, is a no bullshit guy imo.
![Telescope Back Focus: The Ultimate Guide [TAIC Short]](http://i.ytimg.com/vi/5J654T0UpBc/mqdefault.jpg)
I just ran across this video and it is the first video I have ever seen that explains what a reducer does. It is the best timing as I am ready to buy a reducer/flattener for my takahashi which is over $1300. You have saved me $500 for a flattener only. Truly faster is not better in this situation especially in this hobby we spend a fortune on equipment then more to reducer quality for speed doesn’t make sense to me either. Again great info and video
Glad it helped make the decision and quite agree, we spend a fortune on this hobby...Good Luck!
I love the new intro! This was an awesome explanation of a topic I've been curious about, so thankya.
Thanks, this is a confusing topic.
Thanks for this. It’s been 3 years now and I was told the same, that the reducer would speed up my imaging by gathering more light. That just never made sense to me, so I found your video and blogspot when trying to understand what was actually going on. Thank you for your explanation.
Thanks, it is a bit confusing...
Good video, Kurt - very informative!
Thanks for the feedback Chuck!
Very helpful, something that I kind wasn't clear on. Thanks for sharing Kurt. Clear Skies!!!
Thanks for the feed back Luke!
Thanks Kurt!,very well explained ,beautiful image at the end.
Thanks Tam!
Good explanation Kurt. Love the new intro.
Thanks for the comments Robert
thanks...clear skies!
You bet. good Luck.
Really helpful. Thanks!
Thanks Joe! lad it was helpful! - Cheers
I know you did this video almost a year ago. Is there anyplace in your various videos or blogs that you show us what you imaging trains are both with and without the reducer it would really help. Great video and very well explained.
Thanks Marvin: Here is a video that shows it th-cam.com/video/35bgXMcXF2Y/w-d-xo.html. Starting at the camera end it is: Camera, EFW, T2-T2 adapter, 11mm ring, M48-T2 16.5mm extender then the Focal Reducer or Field Flattener. the back Focus is 55mm. - Good Luck
@@AstroQuest1 Thanks so much. Appreciate the help and all of your very well made videos.
@@marvinwhisman3333 You're welcome!
muchas gracias muy educativo
De nada! Pablo.
Thank you for the explanation, Kurt!
Thanks Rob, appreciate the comment.
Thank you for making this video. 👍
Thanks, Glad it was helpful!
what would the effect be, if combining a Focal Reducer and a Barlow Lense together?
Interesting question. I think they may cancel each other out...
That's what I was thinking, I want to use this combination with my dlsr. I think it will help with eyepiece projection inside the adapter
Going up market with the intro😃. Is there a practical limit to how much you can actually reduce down to with a telescope ?
Yeah going up... I am not sure if there is a practical limit but I am not aware of any telescope FRs going below 0.4. Starizona makes that one.
AstroQuest1 yeah I was curious as I have a 72mm 420mm focal length refractor and most reducers seem to be 0.8 but larger scopes seem to have a more reduction down to 0.5 or 0.6
@@rogerwilkinson2818 That's right. Some of those larger scope have very long focal lengths (high F-ratios) narrow FOVs. Their pixel ratios tend to be low as well so a FR would be a great benefit in those cases. Your scope has a good FOV already and (F5.8) lowering much further you would be in the camera lens range.
thanks Kurt, I hate dealing with back focus. even with a caliper, it's impossible to get a good measurement. so, for example a 925mm scope would then become a 666mm. now my pixel size and new focal length would make my pixel scale new correct?
Hey Richard, yes it does get quite confusing but adding a FR will change the scale. There is a website, astronomy.tools/, where you can enter your equipment and it will tell you the scale and such. Cheers
so, if i go from a straight field flattener to to a flattener / reducer does my back focus change? thanks in advance...
Good question Richard, the answer is no. Typically from the the back of a flattener or flattener/reducer it is the same 55mm. Check the manufacture to be sure though. Cheers
How exactly does a focal reducer/field flattener 'flatten the field'. What is curved that needs to be leveled?
Good question, Your sensor is flat as all are but your FOV is not so the edges appear distorted. Lenses and telescopes enhance this distortion. Cheers
"Man Kurt, you just suck!" LOL Probably because you're comparing your outtakes with very 'smooth operators' who never show their multitudinous outtakes. A guy who's not afraid to show his outtakes and realises we'll have a good laugh along with him, is a no bullshit guy imo.
Thanks Mark. Never thought of it that way. Cheers