Takahashi FSQ85 + 0.73x Reducer - Fullframe? - Forums

Topic starter

Feb 4, 2021

Hello, everyone I’m about to buy a takahashi FSQ85 and wonder if the 0. 73x reducer also corrects the full-format field completely.
Have any of you already had experience with this combination or do you have such a setup in use?
TakFSQ85 + 0.73x Reducer + (e. g. Canon 6D)Photos of this combination would be very helpful.

Thank you and CS
Gabriel

Nadir Astro

Feb 4, 2021

Hi Gabriel,

No, 0.73x reducer will not cover fullframe. I suggest that you get 1.01x flattner, friend of mine is using this combination with Canon 6D and field is very flat.

Concise

Gabriel Siegl

Topic starter

Feb 5, 2021

Hello Nadir
Thank you for the answer so you have already helped me a lot.
I would have bought the flattener anyway.

CS Gabriel

Andreas Zeinert

Feb 5, 2021 · Edited: Feb 5, 2021

Hello Gabriel,
I used the 0.73x and now I use the 1.01 flattener on my Atik One which has a medium sized 12.5x10 mm² sensor. The 0.73x did well on my set-up but he is not designed for correcting full frame sensor sizes. The 1.01 is a recent model designed for this according to Takahashi. Even on my small sensor the 1.01 does perform better than the 0.73 in the corners. The FSQ85 is known to possess a non flat field at the genuine 450 mm focal length. This was not important when it was designed since sensors were quite small. Now, every FSQ85 is sold in a pack with the 1.01, guess why ;-)
On the other hand, 0.73 may be an option for gloomy targets as it is much more rapid. You divide your exposure time by almost 2, of course the price to pay is cropping and a lower resolution of your picture. There is always a trade-off to make in astrophotography…

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Min Xie

Feb 6, 2021

0.73x definitely won't cover the full-frame sensor. I got a little dark corners with the APS-C 168c camera.

Gabriel Siegl

Topic starter

Feb 8, 2021

Ok guys. Thank you for your answers- it helped a lot.
I will choose the 1.01 Flattener and not the reducer.
CS Gabriel

Giulio Ercolani

Sep 15, 2022

Min Xie:
0.73x definitely won't cover the full-frame sensor. I got a little dark corners with the APS-C 168c camera.

Hi, were you able to correct the vignetting with flat field?

Min Xie

Sep 15, 2022

Min Xie:
0.73x definitely won't cover the full-frame sensor. I got a little dark corners with the APS-C 168c camera.

Hi, were you able to correct the vignetting with flat field?

As far as I remember, with flats, it could be corrected beautifully for APSC sensor.

AnakChan

Nov 11, 2023

Gabriel/Andrew, Takahashi will be releasing a new QB 0.73x in mid Nov '23 for the FSQ-85ED That's targeted for full frame sensors.

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Bruce Donzanti

Dec 31, 2023

Gabriel/Andrew, Takahashi will be releasing a new QB 0.73x in mid Nov '23 for the FSQ-85ED That's targeted for full frame sensors.

I just received the new reducer and will be trying it with my Baby-Q and ASI6200mm. The Baby-Q works great with the full frame sensor and the 1.01x flattener. So, I am hoping this new reducer will work just as well.

Well Written

AYYYOO I'M GALILEO

Dec 31, 2023

Bruce Donzanti:
Gabriel/Andrew, Takahashi will be releasing a new QB 0.73x in mid Nov '23 for the FSQ-85ED That's targeted for full frame sensors.

I just received the new reducer and will be trying it with my Baby-Q and ASI6200mm. The Baby-Q works great with the full frame sensor and the 1.01x flattener. So, I am hoping this new reducer will work just as well.

I am interested in hearing about your experience with the new reducer @Bruce Donzanti

Philip Herbst

Dec 31, 2023 · Edited: Dec 31, 2023

Hi Gabriel

I have recently acquired a Takahashi baby Q with Flattener. To answer your question, there is a new reducer recently announced by Takahashi that I have coming my way. It is specifically for the FSQ 85 ED and covers full frame. The spot size looks impressive out to a diameter of 44mm (see first link below for spot sizes etc - page in Japanese). It is called the QB 0.73x reducer. Very recently released in Nov 2023.

https://www.takahashijapan.com/ct-news/topics/23xi10_info_fsq85edrdQB073.html
https://teleskop-austria.com/TKA37580

Cheers and CS

Philip

Edit: Sorry, see now this has been answered above by Bruce D.

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AnakChan

Dec 31, 2023

Bruce Donzanti:
Gabriel/Andrew, Takahashi will be releasing a new QB 0.73x in mid Nov '23 for the FSQ-85ED That's targeted for full frame sensors.

I just received the new reducer and will be trying it with my Baby-Q and ASI6200mm. The Baby-Q works great with the full frame sensor and the 1.01x flattener. So, I am hoping this new reducer will work just as well.

Congratulations on your purchase @Bruce Donzanti . Yes I saw your post on Tak Facebook group

. As I replied there too, I'd be very keen to see your results as the samples Tak provided were with the ASI2600 instead of of the ASI6200, and like you I have the ASi6200. Also as some had noted in CN forum the sample pix that Tak provided weren't the best on their ASI2600, as such am curious how it's really like on a proper full frame like the ASI6200.

I was very close to purchasing until I read the CN posts, and am wondering if I should further invest in the FSQ85ED with accessories, or reconsider a complete move to the Vixen VSD90SS.

Bruce Donzanti

Dec 31, 2023

Bruce Donzanti:
Gabriel/Andrew, Takahashi will be releasing a new QB 0.73x in mid Nov '23 for the FSQ-85ED That's targeted for full frame sensors.

I just received the new reducer and will be trying it with my Baby-Q and ASI6200mm. The Baby-Q works great with the full frame sensor and the 1.01x flattener. So, I am hoping this new reducer will work just as well.

Congratulations on your purchase @Bruce Donzanti . Yes I saw your post on Tak Facebook group . As I replied there too, I'd be very keen to see your results as the samples Tak provided were with the ASI2600 instead of of the ASI6200, and like you I have the ASi6200. Also as some had noted in CN forum the sample pix that Tak provided weren't the best on their ASI2600, as such am curious how it's really like on a proper full frame like the ASI6200.

I was very close to purchasing until I read the CN posts, and am wondering if I should further invest in the FSQ85ED with accessories, or reconsider a complete move to the Vixen VSD90SS.

I will certainly let you know once I get it setup. I am optimistic, as I heard people even say in the past that the full frame would not look great on the Baby-Q with the flattener- which is incorrect. The images with the ASI6200 are excellent. You just need patience to really tweak the setup to get it just right with for the backfocus and tilt adjustment. I am going to judge its useful by how I set it up and not some pictures provided by the company. That fact that their ASI2600 pictures might not be good (note: I have not seen them) is ridiculous. I had my ASI2600 on the Baby-Q first and it worked great, so I switched to the ASI6200 and it still worked fine after fiddling with the adjustments.