Focal Reducers for Small Refractors
- jrkirkham
- Articles: 0
- Posts: 957
- Joined: Fri Jun 07, 2019 12:37 am
- 4
- Location: Illinois United States
- Status:
Offline
-
TSS Photo of the Day
TSS Awards Badges
Focal Reducers for Small Refractors
Telescopes: 50mm refractor, ED80 triplet, 90mm makcass, 10" dob, 8"SCT, 11"SCT
Mounts: Celestron CGX, Orion Sirius + several camera tripods
Cameras: Canon 6D, Canon 80D, ZWO-ASI120MC
Binoculars: 10x50, 12x60, 15x70, 25-125x80
Observatory: SkyShed POD XL3 + 8x12 warm room
AL Projects Completed: Lunar #645, Outreach #0280, Universe Sampler #93-T, Binocular Messier #871, Messier #2521, Messier Honorary #2521, Constellation Hunter Northern Skies #112, Planetary Transit Venus #1, Galileo #26, Outreach Stellar 0280, Meteor Regular #157, Solar System Telescopic #209-I, Observer Award #1
AL Projects Currently in Process: Double Stars, Comet, Lunar Evolution
- JayTee
- Articles: 2
- Posts: 5651
- Joined: Thu Apr 25, 2019 3:23 am
- 5
- Location: Idaho, USA
- Status:
Offline
-
TSS Awards Badges
TSS Photo of the Day
Re: Focal Reducers for Small Refractors
Cheers,
JT
∞ AP Scopes: #1: TPO 6" f/9 RC #2: ES 102 f/7 APO #3: ES 80mm f/6 APO
∞ G&G Scopes: #1: Meade 102mm f/7.8 #2: Bresser 102mm f/4.5
∞ Guide Scopes: 70 & 80mm fracs -- The El Cheapo Bros.
∞ Mounts: iOptron CEM70AG, SW EQ6R, Celestron AVX, SLT & GT (Alt-Az), Meade DS2000
∞ Cameras: #1: ZWO ASI294MC Pro #2: 662MC #3: 120MC, Canon T3i, Orion SSAG, WYZE Cam3
∞ Binos: 10X50,11X70,15X70, 25X100 ∞ AP Gear: ZWO EAF and mini EFW and the Optolong L-eXteme filter
∞ EPs: ES 2": 21mm 100° & 30mm 82° Pentax XW: 7, 10, 14, & 20mm 70°
Searching the skies since 1966. "I never met a scope I didn't want to keep."
- JimMinCT
- Articles: 0
- Posts: 393
- Joined: Tue May 07, 2019 10:24 pm
- 5
- Location: Ct
- Status:
Offline
-
TSS Awards Badges
TSS Photo of the Day
Re: Focal Reducers for Small Refractors
Unless you're going for your very own All Sky Survey, (Which is a fine ambition...) I can't see why you'd want to reduce the image scale any further.
Unless you have field curvature, (in which case a
my 2¢
- jrkirkham
- Articles: 0
- Posts: 957
- Joined: Fri Jun 07, 2019 12:37 am
- 4
- Location: Illinois United States
- Status:
Offline
-
TSS Photo of the Day
TSS Awards Badges
Re: Focal Reducers for Small Refractors
Telescopes: 50mm refractor, ED80 triplet, 90mm makcass, 10" dob, 8"SCT, 11"SCT
Mounts: Celestron CGX, Orion Sirius + several camera tripods
Cameras: Canon 6D, Canon 80D, ZWO-ASI120MC
Binoculars: 10x50, 12x60, 15x70, 25-125x80
Observatory: SkyShed POD XL3 + 8x12 warm room
AL Projects Completed: Lunar #645, Outreach #0280, Universe Sampler #93-T, Binocular Messier #871, Messier #2521, Messier Honorary #2521, Constellation Hunter Northern Skies #112, Planetary Transit Venus #1, Galileo #26, Outreach Stellar 0280, Meteor Regular #157, Solar System Telescopic #209-I, Observer Award #1
AL Projects Currently in Process: Double Stars, Comet, Lunar Evolution
- JimMinCT
- Articles: 0
- Posts: 393
- Joined: Tue May 07, 2019 10:24 pm
- 5
- Location: Ct
- Status:
Offline
-
TSS Awards Badges
TSS Photo of the Day
Re: Focal Reducers for Small Refractors
So you do have field curvature... Most all refractors have some. You pay dearly to add that 4th element to remove it.jrkirkham wrote: ↑Mon Nov 04, 2019 2:20 pm Thanks everyone, I was curious about it. It's better to ask before acquiring some new gadget. I have a full-frame DSLR, but I also have a crop factor. I actually like the crop factor better when shooting through the scope. It has an articulating screen that I like looking through if I'm not tethered. It also fills the frame better. I use the full-frame on some of my longer lenses, which are just about as long as my telescope.
If you want to get rid of the crop, and be able to use your whole field of view, then get a good field flattener. I have this one and It works OK.
https://www.highpointscientific.com/tel ... -sca-fft58
I still need to get my spacing tweaked properly. I have a very small amount of streaking in the corners.
It's usually a simple matter if the spacing on your camera works out to be 55mm with the T adapter.
Good Luck!
**edit**
Here's another!
https://www.telescope.com/Orion-Field-F ... /99608.uts
Create an account or sign in to join the discussion
You need to be a member in order to post a reply
Create an account
Not a member? register to join our community
Members can start their own topics & subscribe to topics
It’s free and only takes a minute