I took this picture in early November 2022, but only now I’m posting it. It’s the best Moon picture I took so far, the Askar FRA400 really speaks for itself.
Author: Fernando Schuindt License:CC BY 4.0 Camera: BCF-1 modified Canon T3i Lens/Telescope: Askar FRA400 400mm f/5.6 quintuplet apochromat Composition: 98x Light Frames, ISO 100, 1/1000” Other Gear: Meade LX85 GEM unguided (Two-star basic alignment) Processing: Capturing with APT, pre-processing with PIPP, stacking with AutoStakkert, stretching with RegiStax 6 and editing with Photoshop Location Name: Aracaju - Sergipe, Brazil Location Aprox. Coordinates: 10°57’30.0”S 37°02’30.0”W Timestamp (Local Time): 10-11-2022 from 23:30:51h to 23:31:08h Timezone: UTC-3 (No daylight saving time) Theme: Moon Outdoor temp.: 27° C Outdoor humidity: 77% Backup Images (On Google Photos):https://photos.app.goo.gl/u8faTtVy5mKNXz2H7
Finally, a brief moment of clear night sky. I’m hoping things will start to get better up to the summer. But anyway, this is my first stacked picture using the FRA400 telescope. No guiding, really crude alignment and super short exposures. But even so, I’m happy with the result. Looking forward to improving data gathering and processing techniques.
Author: Fernando Schuindt License:CC BY 4.0 Camera: BCF-1 modified Canon T3i Lens/Telescope: Askar FRA400 400mm f/5.6 quintuplet apochromat Composition: 48x Light Frames 12” (9.6’ total) ISO 1600, 25x dark, 25x flat, 25x bias Processing: Stacking with DeepSky Stacker, Photoshop Levels adjustments and Camera Raw Filter Location Name: Aracaju - Sergipe, Brazil Bortle Scale: 7 Location Aprox. Coordinates: 10°57’30.0”S 37°02’30.0”W Timestamp (Local Time): 10-23-2022 from 00:54h to 01:16h Timezone: UTC-3 (No daylight saving time) Outdoor temp.: 28° C Outdoor humidity: 73% Theme: M42 Center (RA, hms): 05h 35m 47.375s Center (Dec, dms): -05° 44’ 44.402” Legacy Surveys sky browser:Click here Other Gear: Meade LX85 GEM unguided (Two-star basic alignment) Astrometry:https://nova.astrometry.net/user_images/6636562#annotated Backup Images (On Google Photos):https://photos.app.goo.gl/YWpmThGFRFDU1hBt9
For long, I was willing to try to use the big 1390mm focal length ATM scope into my LX85 mount. I knew it was sketchy, but it being well under the maximum mount payload, I decided to give it a try. Also, these days with Jupiter so close I thought it would be a good moment. So I called my buddy Leandro, and we began to set up everything. Many thanks to him.
It is fun to see that huge scope with that GEM. The wind shook the hell out of it, but it was a nice experience.
Author: Fernando Schuindt License:CC BY 4.0 Lens/Telescope:Kugelblitz handmade telescope (210mm aperture, 1390mm focal length, f/6.62, Newtonian) Camera: ZWO ASI462MC (Color) Mount: Meade LX85 GEM Other Gear: Optolong UV/IR-cut filter, Redlab x86 homemade weather-resistant computer Distance: 3.956 AU Magnitude: -2.93 Location Name: Aracaju - Sergipe, Brazil Location Aprox. Coordinates: 10°57’30.0”S 37°02’30.0”W Processing: SharpCap, PIPP, AutoStakkert, RegiStax 6, Photoshop Full Resolution Images:https://photos.app.goo.gl/zMKvb51DQPHMqVAS7
Theme: Jupiter and the Galilean moons
(Click to open full resolution)
Theme: Jupiter and the Galilean moons Composition: 2000 frames captured (11.8GB .avi file), 600 frames stacked Timestamp (UTC-3): 30-09-2022 23:21:27
During the night of May 15th 2022, I went to the SEASE event for the total lunar eclipse at the CCTECA Planetarium Galileu Galilei, in Aracaju - SE, Brazil. I brought with me my homemade 210mm f/6.62 Newtonian Dobsonian telescope and some equipments. The Moon’s FOV on the Canon T3i with that telescope is almost the entire frame, perfect for full-disk single frame photography. That was my first time photographing a lunar eclipse, so I wanted to keep things simple.
The event was really nice, a lot of people went to watch the Moon during its transformations for the night, and I spent a lot of time handling the telescope to the public. People of all ages saw the Moon through my telescope, and I was pleased to make some friends on the spot.
Many thanks to my friend Leandro who was with me all along and helped me during all the tasks, he was super. Also thanks to the SEASE for the space and reception.
Thanks to Augusto from SEASE for sending the pictures to them.
Author: Fernando Schuindt License:CC BY 4.0 Camera: Modified Canon T3i (Baader BCF, by Jordan Patrick) Camera Settings: ISO 1600~3200, 1/5~1/2”, f/6.62* Lens/Telescope:Kugelblitz handmade telescope (210mm aperture, 1390mm focal length, f/6.62, Newtonian) Processing: Capturing without software, Photoshop camera RAW filter, crop, resize and arrangement Location Name: Aracaju - Sergipe, Brazil Location Aprox. Coordinates: 10°56’39.0”S 37°03’21.0”W Theme: Total lunar eclipse Composition: 4 single frames, one for each moment of the eclipse Timestamp (Local Time, UTC-3): 15-05-2022 00:29:18 ~ 16-05-2022 01:16:44 Full Resolution Images:https://photos.app.goo.gl/5dNkmo72mZEEFyir7
(Click to open full resolution)
And here goes a bonus picture I took from the event:
(Click to open full resolution)
My telescope is the one being observed at the middle.
Experimenting with mosaics I think that the IR-pass turned out to be a better approach. Sadly I have missed a bit from the Moon during the IR-pass capture.
Author: Fernando Schuindt License:CC BY 4.0 Camera: ZWO ASI462MC (Color) Lens/Telescope: Meade ETX90 (OTA-only) (90mm aperture, 1250mm focal length, f/13.88, Maksutov-Cassegrain) GEM: Meade LX85 Other Gear: Redlab x86 homemade weather-resistant astronomy computer Processing: Capturing with SharpCap, pre-processing with PIPP, stacking with AutoStakkert, stretching with RegiStax 6, editing with Photoshop and mosaic creation with Microsoft Image Composite Editor Location Name: Aracaju - Sergipe, Brazil Location Aprox. Coordinates: 10°58’31.0”S 37°04’26.0”W Full Resolution Images:https://photos.app.goo.gl/6xuYX1aYLu6xFsim6
Theme: IR-pass waxing crescent Moon mosaic Filters: ZWO IR 850nm pass filter Composition: 8 video files (sections) for a total of 15.9GB Timestamp (Local Time): 10-10-2021 19:52:26 Timestamp (UTC): 10-10-2021 22:52:26
(Click to open full resolution)
Theme: Waxing crescent Moon mosaic Composition: 9 video files (sections) for a total of 53.6GB Timestamp (Local Time): 10-10-2021 19:41:06 Timestamp (UTC): 10-10-2021 22:41:06
The wet season is still bringing lots of rain to my region, but once in a while there’s a good night sky and good opportunity to perform observations and also to take some pictures. As both Jupiter and Saturn are close to the zenith around midnight on a moonless night I thought I’d go for them.
I could say this is my first real planetary image using the ZWO ASI462MC color camera. I’ve performed the following experiments:
I was focusing my attention over Jupiter, so the Saturn picture is really a bonus. The next time I’ll try Saturn, and I’ll also experiment using the ZWO 850nm IR-pass filter.
Even so the ETX90 was taking advantage of a LX85 equatorial mount against a Dobsonian mount of the Kugelblitz, the Kugelblitz images turned a lot more clear. I think that was mainly due to the f/6.62 of the Kugelblitz against the f/13.88 of the ETX90.
I’m also planning to build a Bahtinov mask to aid in focusing, as I was using manual/visual focusing, which makes it pretty hard to achieve good focus.
Author: Fernando Schuindt License:CC BY 4.0 Camera: ZWO ASI462MC (Color) Other Gear: Redlab x86 homemade weather-resistant astronomy computer Location Name: Aracaju - Sergipe, Brazil Location Aprox. Coordinates: 10°58’31.0”S 37°04’26.0”W Full Resolution Images:https://photos.app.goo.gl/ZzZtCWdpbauMmmZz9
Theme: Jupiter and the Galilean moons with notes Distance: 4.039 AU Magnitude: -2.85 Lens/Telescope:Kugelblitz handmade telescope (210mm aperture, 1390mm focal length, f/6.62, Newtonian) Composition: 2698 frames captured (16.7GB .avi file), 700 frames stacked Processing: AutoStakkert for stacking, RegiStax 6 for stretching and Photoshop for processing Timestamp (Local Time): 06-08-2021 22:19:21 Timestamp (UTC): 07-08-2021 01:19:21
(Click to open full resolution)
Theme: Jupiter and the Galilean moons without notes Distance: 4.039 AU Magnitude: -2.85 Lens/Telescope:Kugelblitz handmade telescope (210mm aperture, 1390mm focal length, f/6.62, Newtonian) Composition: 2698 frames captured (16.7GB .avi file), 700 frames stacked Processing: AutoStakkert for stacking, RegiStax 6 for stretching and Photoshop for processing Timestamp (Local Time): 06-08-2021 22:19:21 Timestamp (UTC): 07-08-2021 01:19:21
(Click to open full resolution)
Theme: Saturn Distance: 8.938 AU Magnitude: 0.19 Lens/Telescope: Meade ETX90 (OTA-only) (90mm aperture, 1250mm focal length, f/13.88, Maksutov-Cassegrain) Other Gear: Meade LX85 GEM (unguided, two-star alignment) Composition: 1002 frames captured (5.94GB .avi file), 500 frames stacked Processing: AutoStakkert for stacking, RegiStax 6 for stretching and Photoshop for processing Timestamp (Local Time): 06-08-2021 23:06:00 Timestamp (UTC): 07-08-2021 02:06:00
(Click to open full resolution)
Gear
ETX90, LX85, 462MC and the redlab. (And Zig on the background)
[ZWO ASI462MC]
Pan=0
Tilt=0
Output Format=AVI files (*.avi)
Binning=1
Capture Area=1936x1096
Colour Space=RGB24
Temperature=36
High Speed Mode=On
Turbo USB=100(Auto)
Flip=None
Frame Rate Limit=Maximum
Gain=114
Exposure=0.003776
Timestamp Frames=Off
White Bal (B)=63(Auto)
White Bal (R)=53
Brightness=102
Auto Exp Max Gain=300
Auto Exp Max Exp M S=30000
Auto Exp Target Brightness=130
Mono Bin=Off
Banding Threshold=35
Banding Suppression=0
Apply Flat=None
Subtract Dark=None
#Black Point
Display Black Point=0
#MidTone Point
Display MidTone Point=0.521367521367521
#White Point
Display White Point=1
Notes=
TimeStamp=2021-08-06T01:19:21.7457571Z
SharpCapVersion=3.2.6482.0
Saturn:
[ZWO ASI462MC]
Pan=0
Tilt=0
Output Format=AVI files (*.avi)
Binning=1
Capture Area=1936x1096
Colour Space=RGB24
Temperature=31.1
High Speed Mode=On
Turbo USB=100(Auto)
Flip=None
Frame Rate Limit=Maximum
Gain=264
Exposure=0.015104
Timestamp Frames=Off
White Bal (B)=57(Auto)
White Bal (R)=58
Brightness=152
Auto Exp Max Gain=300
Auto Exp Max Exp M S=30000
Auto Exp Target Brightness=130
Mono Bin=Off
Banding Threshold=35
Banding Suppression=0
Apply Flat=None
Subtract Dark=None
#Black Point
Display Black Point=0
#MidTone Point
Display MidTone Point=0.521367521367521
#White Point
Display White Point=1
Notes=
TimeStamp=2021-08-06T02:06:00.7942288Z
SharpCapVersion=3.2.6482.0
Close up on the Moon using the ASI426MC camera with a 1250mm focal distance / 90mm aperture (f/13.88) telescope on top of a Meade LX85 computerized german equatorial mount.
Author: Fernando Schuindt License:CC BY 4.0 Camera: ZWO ASI462MC Lens/Telescope: Meade ETX 90 (OTA-only) (90mm aperture, 1250mm focal distance, f/13.88, Maksutov-Cassegrain) Mount: Meade LX85 GEM (Two-star alignment). Software: SharpCap 3.2, PIPP, AutoStakkert, RegiStax 6, Adobe Photoshop CC 2015. Location Name: Aracaju - Sergipe, Brazil Bortle Scale: 7 Location Aprox. Coordinates: 10°58’31.0”S 37°04’26.0”W Timezone: UTC-3 (No daylight saving time) Outdoor temp.: 26° C Outdoor humidity: 98% Backup Images (On Google Photos):https://photos.app.goo.gl/C6m7Ebpt6Qj83VSCA
[ZWO ASI462MC]
Pan=0
Tilt=0
Output Format=AVI files (*.avi)
Binning=1
Capture Area=1936x1096
Colour Space=RGB24
Temperature=35.3
High Speed Mode=On
Turbo USB=100(Auto)
Flip=None
Frame Rate Limit=120 fps
Gain=64
Exposure=0.032
Timestamp Frames=Off
White Bal (B)=65(Auto)
White Bal (R)=53
Brightness=78
Auto Exp Max Gain=300
Auto Exp Max Exp M S=30000
Auto Exp Target Brightness=130
Mono Bin=Off
Banding Threshold=35
Banding Suppression=0
Apply Flat=None
Subtract Dark=None
#Black Point
Display Black Point=0
#MidTone Point
Display MidTone Point=0.521367521367521
#White Point
Display White Point=1
Notes=
TimeStamp=2021-06-16T22:38:22.0496841Z
SharpCapVersion=3.2.6482.0
[ZWO ASI462MC]
Pan=0
Tilt=0
Output Format=AVI files (*.avi)
Binning=1
Capture Area=1936x1096
Colour Space=RGB24
Temperature=34.6
High Speed Mode=On
Turbo USB=100(Auto)
Flip=None
Frame Rate Limit=Maximum
Gain=364
Exposure=0.016
Timestamp Frames=Off
White Bal (B)=76(Auto)
White Bal (R)=53
Brightness=102
Auto Exp Max Gain=300
Auto Exp Max Exp M S=30000
Auto Exp Target Brightness=130
Mono Bin=Off
Banding Threshold=35
Banding Suppression=0
Apply Flat=None
Subtract Dark=None
#Black Point
Display Black Point=0
#MidTone Point
Display MidTone Point=0.521367521367521
#White Point
Display White Point=1
Notes=
TimeStamp=2021-06-16T23:09:05.1548647Z
SharpCapVersion=3.2.6482.0
A wonderful night with essentially no clouds and no Moon. For a long time I’ve been planning to image Sirius A, the brightest star of our night sky. A main sequence star on Canis Major.
I’ve set up KStars on my notebook to wireless control my camera and mount using INDI on my homebuilt science station, so I programmed the set of exposures and left it running over the night while I enjoyed other targets with my dobsonian.
Author: Fernando Schuindt License:CC BY 4.0 Camera: Canon EOS 600D Lens/Telescope: Lens Zuiko Olympus 300mm f/4.5 Manual-Focus OM (Film) Composition: 42x Light Frames 28” (19.6’ total) ISO 800 f/8, 25x Dark, 25x Flat, 25x Bias Processing: Stacking with DeepSky Stacker, Photoshop Levels adjustments and Camera Raw Filter Location Name: Aracaju - Sergipe, Brazil Bortle Scale: 7 Location Aprox. Coordinates: 10°58’31.0”S 37°04’26.0”W Timestamp (Local Time): From 11-23-2020 00:00:00 to 11-23-2020 00:33:10 Timezone: UTC-3 (No daylight saving time) Outdoor temp.: 26° C Outdoor humidity: 96% Theme: Sirius Center (RA, hms): 06h 45m 28.570s Center (Dec, dms): -16° 44’ 31.236” Legacy Surveys sky browser:Click here Other Gear: Meade LX85 GEM unguided (Two-star alignment), OM-EOS adapter, homebuilt INDI wireless control station, KStars connected to INDI running on a Manjaro Linux x86 notebook.
Astrometry:http://nova.astrometry.net/user_images/4171943#annotated Backup Images (On Google Photos):https://photos.app.goo.gl/c2LqFysiHfPPEwbs7
That’s my first stacked picture taken since my first polar alignment, I’m super excited!
Author: Fernando Schuindt License:CC BY 4.0 Camera: Canon EOS 600D Lens/Telescope: Lens Zuiko Olympus 300mm f/4.5 Manual-Focus OM (Film) Composition: 19x Light Frame 40” (12.66’ total) ISO800 f/4.5, 25x Dark, 25x Flat, 25x Bias Processing: Stacking with DeepSky Stacker, Photoshop Levels adjustments and Camera Raw Filter Location Name: Aracaju - Sergipe, Brazil Bortle Scale: 7 Location Aprox. Coordinates: 10°58’31.0”S 37°04’26.0”W Timestamp (Local Time): From 11-13-2020 23:25:24 to 11-13-2020 23:54:30 Timezone: UTC-3 (No daylight saving time) Theme: Comet C/2020 M3 ATLAS Center (RA, hms): 05h 25m 58.341s Center (Dec, dms): +03° 59’ 31.651” Legacy Surveys sky browser:Click here Other Gear: Meade LX85 GEM unguided (Two-star alignment), OM-EOS adapter, homebuilt INDI wireless control station, KStars connected to INDI running on a Manjaro Linux x86 notebook.
Astrometry:https://nova.astrometry.net/user_images/4145606 Full Resolution Images (On Google Photos):https://photos.app.goo.gl/ePXtc8o39rtynfs28
This post was originally published on my old blog dedicated to amateur astronomy.
Last week I bought an used Meade ETX 90 (90mm Maksutov), the fork mount was broken so I bought only the OTA to be used with my Meade LX85 equatorial mount. The OTA also had a problem with the 90° flip mirror mechanism to change the focuser image position, it was stuck on the upright 90° position, which is not only a bad place to fix a DSLR but it also makes the visual/AP change process a complicated one. I’ll manage a way to fix this mechanism ASAP, but in the meantime I’m using the DSLR in the upright position.
Another issue I had was my LX85 counterweight is way too heavy for this kind of payload. I had an old EQ1 mount with a smaller weight ideal for it, but the shaft role was smaller than the size of the LX85’s shaft. So I went to a local metal workshop (Acej) and asked them to enlarge the shaft hole for me, they couldn’t do it better, I got it as a perfect fit for the bigger shaft and then was able to balance the payload. Thanks to Andre Figueirêdo for helping me with subjects around 90mm Maksutovs and for giving me the Acej reference. He’s a really talented local astrophotographer.
That aside, I can say it’s superb equipment for planets and the Moon. Had an incredible night with Catarina gazing between Jupiter, Saturn and the Moon. I got really happy watching her faces and expressions while gazing through this scope, I think it’s a night I will never forget. The weather was also surprisingly comfortable.
She went to sleep around midnight, this time I was switching from visual to photography.
I also had brought my notebook to the garden and I was willing to use it to control the camera and the mount, but the Camera->Computer connection is a tricky one. 10m long USB cables are far from the ideal, but it works. Unless you’re passing through the USB device to a virtual machine. The problem is that my notebook runs Linux, and I haven’t yet got lucky with DSLR/mount controls on it. I always do it on my Win10 desktop, but it’s a desktop, I can do it only inside my office, not in the garden. So for that I had a virtual Win10 running on my Linux notebook. Controlling the mount from it works OK, but the DSLR will keep disconnecting every minute.
I’m yet to manage a solution for this, but for the night I ended up not using the computer, just the DSLR itself and the mount handheld controller.
No fancy/cool techniques were used in the shots, just straight-forward single light frames and Photoshop editing, so definitely those equipment can do a lot better. Also mind that even larger magnifications can be achieved when using a 3x barlow lens, which is a plan for the future.
When I was about to wrap up for the night, my neighbor appeared and we started talking about telescopes. I soon invited him to come in and observe (keeping safe distance, as we both observe Covid-19 quarantine) and I think he enjoyed it a lot. He told me he owns a small refractor and that he’s studying astronomy, how cool? He said he’s starting his career on software development but programs since 2014, so we also spent a lot of time talking about IT.
Then I packed the stuff and got up back to the office, performed a really quick/crappy edition and called the night.
Author: Fernando Schuindt License:CC BY 4.0 Camera: Canon EOS 600d Lens/Telescope: Meade ETX 90 (OTA-only) (90mm aperture, 1250mm focal length, f/13.88, Maksutov-Cassegrain) Location Name: Aracaju - Sergipe, Brazil Location Aprox. Coordinates: 10°58’31.0”S 37°04’26.0”W Other Gear: Meade LX85 GEM, Canon EOS to M42 adapter, M42 to 1.25” adapter. Full Resolution Images:https://photos.app.goo.gl/GG4DzQkPTRJuuFJQ7
This post was originally published on my old blog dedicated to amateur astronomy.
It’s Brazilian carnival once more, one of the biggest local holidays around here. It’s a time of parties and lots of people in the streets. For me it’s being a time of retirement and relaxation. And by that I mean being alone in my house spending the entire holiday on the internet, or with friends and family in some not crowded small city with some good nature, away from all the craziness that is the carnival. Don’t get me wrong, it’s fun, but taking the time to enjoy nature and relax is too. So I did.
The oldest friend I have (He’s son of my father’s best friend, so I know him long enough to don’t even remember when we first met) invited me to spend the carnival in his family’s estate, 1 hour driving from the town. A really nice, beautiful and comfortable place. Thank you Iago, for everything.
It was my first time visiting the place, so I asked him about the night sky, and he reported it was heavily polluted. So I decided not to bring my astronomy equipment, just my wife’s DSLR. (Just in case). I haven’t even brought any tripod. Nothing but the DSLR. And oh boy! I should have brought everything, not only the night sky was really nice (probably a Bortle Scale 5) but we spent the first night with very little clouds.
So I decided to improvise, got myself a pillow and placed it on the ground with the DSLR on top pointing upwards and managed to take some shots. After some in-house picking of the best shot and some edition, here’s the result.
This post was originally published on my old blog dedicated to amateur astronomy.
This one took me quite a good time to process, ended up making 3 versions of it and sticking with the latest. It’s the first time I programmed a galaxy themed picture so my inexperience spoke during the whole process.
The plan was to put two or more galaxies in the frame with a low budget plan (the remaining usage time I had on iTelescope). I was aiming to the Leo Triplet, a group of 3 galaxies also known as the M66 group. But I was using a deep field telescope (0.43-m f/6.8 reflector + CCD + f/4.5 focal reducer) so I ended up taking just two of the three galaxies: NGC 3628 (the Hamburger Galaxy / M65 and NGC 3627 (the M66).
The image composition is the following:
4x 30” Luminous frame
4x 30” Red frame
4x 30” Green frame
4x 30” Blue frame
The images were stacked using DeepSky Stacker and stretched using Adobe Photoshop.
This post was originally published on my old blog dedicated to amateur astronomy.
As I’m studying a lot about AP, I thought would be nice to give a try to iTelescope.net systems, and it was pretty fun. I picked the Siding Spring Observatory in Australia and the T8 telescope, which is a 106mm Takahashi FSQ Apochromatic, 0.10-m f/5 telescope. The target was NGC 3372, the Eta Carinae Nebula.
This is a quite special DSO to me, as it’s the first object that I got in love with and started my fascination for deep sky in general. It all started with a video by my favorite YouTube channel: Sixty Symbols. The video was this one here, with the professor Mike Merrifield.
I never had access to such equipment before, so I got really exited with the filter selection and ordered a 32” exposure for each filter available. I just wanted to see it, haha. So I ended up with some frames that I had no use for.
I used:
1x 32” Luminous frame
1x 32” Red filter frame
1x 32” Green filter frame
1x 32” Blue filter frame
1x 32” Hydrogen Alpha filter frame
Just one short frame for each filter I wanted to use, because that’s a budget project, hahaha.
When the frames arrived I thought I had messed up with something, they looked really dark. But after merging the Red and Ha frames, then the other channels (Green and Blue) and composing the HaRGB image with some stretching in Adobe Photoshop, it looked really nice for my newbie taste. As the CCD on the camera is Black&White, the colors were composed by using R, G and B filters. In this case the Red channel is merged with the Hydrogen Alpha channel, to reveal Hydrogen based structures with more detail.
To give an idea, this is how one of the frames looks like without any processing (the Red frame, smaller size tho):
I’ve also produced another image without the Ha filter:
Fun fact is that the NGC 3532 (Wishing Well Cluster) is right there in the bottom right corner, I loved it. So I’m already waiting for my new schedule to happen, I won’t reveal it yet, but I’m hopping to see two galaxies in the next picture.
Again a special thanks to Terry F. for his teachings.