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I spend this website many hours each week to share my knowledge and experience from the areas of Astronomy, Cars and Travels. Most pages are written in English that is not my own native language, so do not judge me too hard if you find grammatical errors and more.

Highlights!

(these pages could be a mix of Swedish and English)

Contents:

• NewsMostly highlights on Astrofriend's homepage, see also left column Latest News
• New linksInteresting information
• Must do stuffWhat makes your life valuable
• Speech nature science, Föredrag naturvetenskap(most speeches in Swedish)

News:

Here I have collected news I found interesting.

Technology, Astronomy, Cars, Travels etc.

June 16, 2021 Astronomy: Project

• At my balcony I have Bortle class 9, as worst as it can be. Still it's very practical to have the equipment at the balcony when testing out new technology. Now I do a more practical connection of the 12 Volt power and ethernet:

  astronomy/ projects/ project-astro-server-and-powerunit/ 31-astro-server-and-powerunit.html
  (Project: Outdoor 12 Volt and LAN outlet)

Other astronomy projects:

June 12, 2021 Astronomy: Project

• After I had rebuilding my EQ6 mount to timing belt drive I could do some test the last winter. Most worked as expected, but the internal stepper motor driver has some problem. There is a bug in the driver, EQMOD has implemented the RA drift compensating to handle this. With my custom gear ratio it was on the limit to handle it. But one thing that is more difficult to handle is that when running Raspberry with EQMOD INDI it's not possible to have a custom gear ratio. I can alter the driver because it's an open source, but better to change the stepper motor driver and get rid of the bug. I have started to implement the AstroEQ driver:

  astronomy/ projects/ project-eq6-dismantling-rebuilding/ 20-eq6-dismantling-rebuilding.html
  (Project: EQ6 dismantling and rebuilding)

Other astronomy projects:

May 22, 2021 Astronomy: Project

• Recently I bought a HEQ5 mount. My idea is to use that mount when travel by my car. Much less weight compare to my EQ6 mount. When I'm using my 300 mm lens I don't need the stability of the EQ6, and the HEQ5 mount has about the same precision. Problems solve: the serial cable, the EQDIRECT has not the same connector and not so good power connector:

  astronomy/ projects/ project-heq6/ 01-heq5.html
  (Project: HEQ5)

Update:
Reducing cable clutter, shorten GPS cable (page 7)
Power consumption
Setup of GPS NMEA
Setup of GPSD
Succeeded to run Astroberry (page 6)
Setup the Raspberry system
Installing 300 mm astrophoto equipment on HEQ5
Install a better power connector
Change from 9-pol D-sub to RJ45 standard.

Other astronomy projects:

May 13, 2021 Astronomy: Project

• When updating my equipment with a medium format Pentax 645 300 mm ED f/4 lens I also do a lot of other updates. This is an implementation of an auto focus system. Test it with APT and N.I.N.A.:

  astronomy/ projects/ project-pentax645-300ed/ 01-pentax645-300ed.html
  (Project: Medium format Pentax 645 300 mm ED f/4 lens)

Update:
New FTDI cable arrive and a test of it (page 8)
Investigating the FTDI cables
A second try at the observatory
Move the equipment to the observatory
Tilted focus plane
Autofocus with APT, N.I.N.A.

Other astronomy projects:

May 9, 2021 3D-printing: CAD

• When I put the EQ6 head on my pier I must have a pad between. I made one of wood to test and the plan was to replace it with one made of aluminum. But now when I have my 3D-printer, can I 3D-print a pad or will it be too weak to work properly ?

  3d-printing/ eq6-pad/ 01-eq6-pad.html
  (CAD: EQ6 Pad)

Update:
Install the EQ6 pad (page 2)
New design of EQ6 pad (page 2)
Test of EQ6 pad
Designed one more pad, this one for HEQ5

Other about 3D-printing and CAD:

May 5, 2021 Astronomy, observatory site

• Uppsala old observatory, this observatory was one part of the story of Sweden's old observatories I translated earlier. Today a sun shine day we took the car and visited it:

  astronomy/ observatory-sites/ uppsala-old-observatory/ 01-uppsala-old-observatory.html
  (Uppsala old Observatory, 2021)

Update:
Uppsala telescope in Australia.

Other observatory sites:

April 30, 2021 Astronomy, photography

Now the fun have started, I can take the first step with my Raspberry controlled astrograph. The lens is the Pentax 645 medium format 300 mm ED f/4 used at full aperture:

• astronomy/ astronomy-photo/ open-clusters/ m39/ m39-open-cluster.html
  (M39 Open Cluster, 2021)

Other Open Clusters:

April 24, 2021 Cars, Chrysler Crossfire repair:

• My car drain the battery when parked for more than three weeks. I did some measurement of this:

  vehicles/ my-cars/ chrysler-crossfire/ battery-replacement/ battery-replacement.html
  (Battery current drain)

  Update:
  New battery once again (page 1)
  Battery drain (page 2)

Other DIY repair tips for Chrysler Crossfire (Mercedes):

April 22, 2021 3D printer

• After a brake of more than a year I started my work on the 3D printer setup once again:

  3d-printing/ 3d-printer-setup/ 01-3d-printer-setup.html
  (3D Printer, assembling and setup)

Update:
P.I.D. optimizing
Tweaked printer head rods with springs (page 14)
Setup with Marlin 2.0.0
Setup with Marlin 1.1.9
Printer calibration
Update 3D printer software
Mechanical calibration

Other 3D Printer and CAD projects:

April 19, 2021 Astronomy: Project

• With the new HEQ5 mount I have to rebuilt the pier to accept even this mount:

  astronomy/ projects/ project-pier-mount/ project-pier-mount.html
  (Project: Pier for a EQ6 / HEQ5 mount)

Other astronomy projects:

April 15, 2021 Astronomy: Project

• My friend Lars B do most of his projects from the very basic, cast worm gears, 3D-print details etc:

  astronomy/ projects/ project-do-it-from-basic-by-larsb/ 01-do-it-from-basic-by-larsb.html
  (Project: Lars B's projects)

Update:
Mount and pier
Welding in aluminum
3D-printed focuser

Other astronomy projects:

April 12, 2021 Cars, Chrysler Crossfire repair:

• I have some thought about the rear height of the car and checking the springs condition:

  vehicles/ my-cars/ chrysler-crossfire/ springs/ 01-springs-rear.html
  (Wheels: Springs rear)

Other DIY repair tips for Chrysler Crossfire (Mercedes):

April 7, 2021 Astronomy: Lens data base

• When using a lens' built in focus motor it could behave different when controlling focus by remote. I have here collected some information from APT forum to get a better overview of which lenses is to prefer to use for astrophoto in that sense:

  astronomy/ tutorials/ database-apt-focus-af-mf-lenses/ database-apt-focus-af-mf-lenses.html
  (Data base: lenses autofocus behavior when remote controlled)

Other astronomy tutorials:

April 3, 2021 3D-printing: CAD

• Today I'm 3D-printing a viewfinder cover for Canon EOS 6D, maybe it fit all other Canon EOS DSLR cameras as well.

  3d-printing/ viewfinder-cover/ 01-viewfinder-cover.html
  (CAD: Viewfinder cover, Canon EOS DSLR 6D)

Other about 3D-printing and CAD:

April 1, 2021 Cars, Chrysler Crossfire repair:

• The textile of the inner roof panel has got loose and need a repair:

  vehicles/my-cars/ chrysler-crossfire/ interior/ 03-chrysler-crossfire-interior.html
  (Wheels: Roof inner panel)

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Mars 24, 2021 Astronomy, photography

Maybe you have read in the news papers about a new bright Nova at the sky. A Nova is an exploding star. I managed to take a photo of it from my light polluted balcony:

• astronomy/ astronomy-photo/ novas/ v1405-cas/ v1405-nova.html
  (Nova V1405 Cas, 2021)

Update:
One more photo 23/4-21.

Other Novas:

Mars 23, 2021 Astronomy

Gösta Gahm

I, Gösta and Peter at the Sweden Solar system presentation, Gunilla is the photographer.

Something very sad has happen, in January 2021 I got the information that Gösta had passed away. We had known each other for more than 25 years, both I and Gunilla had him as a teacher in more than one courses we took in astronomy from 1995 to 2002 and we kept the contact since then. This meeting with the Jupiter model was the last time we saw him and at Christmas I got a greeting from him, since then nothing. Goodbye Gösta, we hope you have a great time up among the stars !

Lars and Gunilla

• astronomy/ astronomy-articles/ sweden-solar-system-jupiter-2019/ sweden-solar-system-jupiter.html
  (Sweden Solar system, Jupiter)
• https://en.wikipedia.org/ wiki/ Gösta_Gahm
  (Gösta Gahm, Wikipedia)

Mars 20, 2021 Astronomy, photography

At last I could do some astrophotographing with my new Pentax medium format lens. There are problems that must be solved but what I can see this lens will be high performance astro catcher:

• astronomy/ astronomy-photo/ globular-clusters/ m13/ m13-globular-cluster.html
  (Messier 13, 2021)

Other Globular Clusters:

Mars 20, 2021 Astronomy: Project

• A simple test of the vignetting on my new Pentax 645 300 mm ED f/4 medium format lens used on a full frame camera:

  astronomy/ projects/ project-different-lenses-vignetting/ 01-different-lenses-vignetting.html
  (Vignetting of my lenses)

Other astronomy projects:

Mars 8, 2021 Astronomy, observatory site

• Tamm's observatory, this was more an accident that we found this observatory. This day we was in the forest and hunting for Sweden's ancient history when we found this. I know about it but thought it was more to the North:

  astronomy/ observatory-sites/ tamms-observatory/ 01-tamms-observatory.html
  (Tamm's Observatory, 2021)

Other observatory sites:

Mars 4, 2021 3D-printing: CAD

• A shim to place between the Canon EOS camera and the lens to reduce the tilt of the sensor.

  3d-printing/ shim-canon/ 01-shim-canon.html
  (CAD: Shim for Canon EOS bayonet)

Other about 3D-printing and CAD:

Mars 13, 2021 Cars, Chrysler Crossfire repair:

• Investigating the car's Hub Center Rings:

  vehicles/my-cars/ chrysler-crossfire/ hub-center-rings/ hub-center-rings-01.html
  (Wheels: Hub Center Rings)

  Update:
  Special designed hub rings (page 3)
  3D printed Hub rings.

Other DIY repair tips for Chrysler Crossfire (Mercedes):

February 11, 2021 3D-printing: CAD

• Bracket to hold the a Pentax 645 300 mm f 1/4 ED lens:

  3d-printing/ pentax645-300mm-bracket/ 01-pentax645-300mm-bracket.html
  (CAD: bracket for Pentax 645 300 mm lens)

Update:
180 teeth pulley
Front bracket

Other about 3D-printing and CAD:

February 4, 2021 3D-printing: CAD

• My first CAD, a bracket for the motor focuser:

  3d-printing/ cad-drawing/ 01-cad-drawing.html
  (CAD: motor focuser bracket)

Update:
Version 4, a more stiff design.
Version 3, continue.
New 400 mm timing belt has arrived (page 4).
Belt length calculation.
Version 3.
Version 2.

Other about 3D-printing and CAD:

February 15, 2021 Astronomy: Project

• As a part of my project: Belt modification of EQ6 mount I now investigating the EQMOD's strange RA drift compensation:

  astronomy/ projects/ project-eq6-dismantling-rebuilding/ 19-eq6-dismantling-rebuilding.html
  (Project: EQ6 belt modification, RA drift compensation)

Update:
Implement of AstroEQ ?

Other astronomy projects:

February 1, 2021 Astronomy: Project

• I bought new USB powered dew heaters with a more narrow design and included power regulators. I did some power measurements of them:

  astronomy/ projects/project-heating-band/ 05-project-heating-band.html
  (Project: Dew heaters)

Other astronomy projects:

January 31, 2021 Astronomy: Project

• Bad weather again, I need something exiting to do. My earlier test with a Canon 300 mm f/4 L lens mounted on my Star Adventurer worked but need an auto guiding, I also want a GoTo function. I started to put together a setup where I can us my EQ6 mount and borrowed some parts from the big APO refractor:

  astronomy/ projects/ project-300mm-setup/ 01-300mm-setup.html
  (Project: EQ6 mount and 300 mm lens)

Update:
Preparing second outdoor test
Upgrade to SSD drive and Windows 10, page 5
Preparing first outdoor test
Focus motor test and calibration
Camera external power adapter
Volt and Amp instrument
Mounting bracket for motor focuser
New USB Hub and new power cables
Adjusting the extender width of guide lens.

Other astronomy projects:

29 januari, 2021 Resor till sjöss

Nyheter om det år 1940 förlista fartyget S/S Sylvia:

• En släkting till en av de omkomna har hittat till min sida om fartyget S/S Sylvia och har en del att berätta:

  vehicles/ ship-sylvia-1940/ 01-sylvia-sv.html
  (Fartyget S/S blir torpederat år 1940)

Other history related:

January 26, 2021 3D-printing: CAD

• Now it's time to replace my prototype board for my Mini PC's peripherals:

  3d-printing/ minipc-enclosure/ 01-minipc-enclosure.html
  (CAD: Power terminal enclosure)

Other about 3D-printing and CAD:

January 22, 2021 3D-printing: CAD

• One thing I left from my father is an old compass. He used it on his mahogany cruiser during the 1960s. But I miss the mount to it:

  3d-printing/ compass-stand/ 01-compass-mount.html
  (CAD: Compass mount)

Other about 3D-printing and CAD:

January 13, 2021 3D-printing: CAD

• Bracket to hold the QHY5 camera and Tokina 200 mm lens that I use for auto guiding:

  3d-printing/ qhy5-bracket/ 01-qhy5-bracket.html
  (CAD: bracket for QHY5 camera)

Other about 3D-printing and CAD:

January 9, 2021 3D CAD

• In this project I make drawings for GT2 pulleys that I will use in my lens focuser:

  3d-printing/ camera-lens-focus-gears/ 01-camera-lens-focus-gears.html
  (Making drawings for GT2 pulleys to lens focuser)

Update:
New 180 teeth GT2 Pulley.

Other 3D Printer and CAD projects:

December 27, 2020 3D printing

• Something I had thought about a long time is to 3D-print an adapter to my polar finder telescope so I can attach a camera angled viewfinder:

  3d-printing/ 90degree-polarfinder-adapter/ 01-90degree-polarfinder-adapter.html
  (Adapter for polar telescope finder to 90 degree camera viewer)

Other 3D Printer and CAD projects:

December 23, 2020 Astronomy

• Astronomical observatories in Sweden, by Östen Bergstrand. I found a copy of a more than 80 years old article from a magazine. It's written by a Swedish astronomer from Uppsala. Only in Swedish of course, but I have translated it into English for you who find it interesting:

  astronomy/ observatory-sites/ swedens-old-observatories/ 01-swedens-old-observatories.html
  (Astronomical observatories in Sweden, written 1931, translated into English 2020)

At the page there is also a link to the Swedish original article.

Update:
All pages are now translated and online.

Other observatory sites:

28 december, 2020 Resor till sjöss

Min fars äventyr som sjöman under åren 1937 till 1945:

• Vem har inte drömt om att göra en jorden runt resa någon gång i sitt liv. Min pappa Evert gjorde det redan innan han var 20 år fyllda. Han mönstrade på handelsfartyg och hamnade ända borta i Kina och andra länder i Asien. Det här skedde delvis under Andra Världskriget, det var många fartyg som gick under från minor och torpeder, även svenska fartyg. Tre av fartygen han var på förliste pga detta, dock något efter att han mönstrat av. Trevligt nog har jag en hel del bilder till pappas alla berättelser om de här 7 åren till sjöss. Denna spännande historia kan ni följa här:

  travel/ world/ evert-at-sea-1937-1945/ 01-evert-at-sea-start-sv.html
  (Min fars äventyr till havs åren 1937 - 1945)

Uppdatering:
Sjömansrulla för fartyget S/S Baltia
Sjömansrulla för fartyget S/S Caring
Sjömansrulla för fartyget S/S Masilia
Interiörbilder från Engelsbergsarkivet av fartyget M/S Axel Johnson III
Sjömansrulla för fartyget S/S Torsa
Sjömansrulla för fartyget S/S Maria Gorthon

Other history related:

November 23, 2020 Cars, Chrysler Crossfire Wheels:

My old wheels have a lot of scratches and the wheels at rear look at bit small. I did some calculation to find which size of wheels and tires that fit in the back.

• Wheels and tires:

  vehicles/ my-cars/ chrysler-crossfire/ wheels-tires/ wheels-tires-01.html
  (New wheels and tires at rear axle)

Other DIY repair tips for Chrysler Crossfire (Mercedes):

November 19, 2020 Astronomy

• When looking at internet there are almost no pages of Stockholm's Observatory. Now I change that with my own page with a lot of photographs of the exterior:

  astronomy/ observatory-sites/ saltsjobaden-observatory/ 01-stockholms-observatory.html
  (Stockholm's Observatory, 2020)

Updates:
Added more links with information.

Other observatory sites:

15 november, 2020

Befästningslinjen Södra fronten: Svensk historia

• Under Coronatider gäller det att hitta spännande saker att besöka på en dagsturs avstånd. Det här är ett försvarsverk du finner söder om Stockholm.

  history/ befastningslinjen-sodra-fronten/ befastningslinjen-sodra-fronten.html
  (Befästningslinjen Södra Fronten, Sveriges historia)

Uppdatering:
Sjötorpsfortet tillagt.
Sundbyfortet tillagt.
Måndalsfortet tillagt, det sista fortet på denna försvarslinje.

Annan historia relaterad till Sverige:

21 Oktober, 2020 Astronomy, meteorit krater

Jag har här skrivit om ett par gamla artikelar och gjort de online på hemsidan. Det är meteoritnedslagen vid Dellensjöarna och Funäsdalen:

• astronomy/ meteorite-craters/ meteorite-dellen.html
  (Meteorit kratern Dellen, 2006)
• astronomy/ meteorite-craters/ meteorite-tor.html
  (Meteorit kratern TOR, 2005)

Andra meteoritkratrar:

October 13, 2020 Cars, Chrysler Crossfire repair:

It was long time since I had to do any repair on my car. Now when winter is coming and it start to be cold. What happen then ? The engine doesn't start !

• Replacing the engine crankshaft sensor:

  vehicles/ my-cars/ chrysler-crossfire/ crankshaft-sensor/ crankshaft-sensor-01.html
  (Replacing the crankshaft sensor)

Update:
Now the sensor is replaced and the engine starts, still to test during longer period.

Other DIY repair tips for Chrysler Crossfire (Mercedes):

September 2, 2020 Travel

• These are some old photos I took long time ago. We were on the road with a new car and stopped at the hotel Gyllene Uttern. The following morning we found the nearby village Röttle. One of the most beautiful places I have visited:

  travel/ sweden/ rottle-brahehus-2007/ 01-gyllene-uttern.html
  (Röttle, Sweden 2007)

  There are also some photos from the castle Brahehus.

Other travels in Sweden:

2 september, 2020

Vaxholms Yttre Befästningslinje: Svensk historia

• Jag upplevde många tyckte det var spännande med vårt försvars gamla befästningar. Inspirerade mig att skriva om en annan, Vaxholms Yttre Befästningslinje. En av forten som ingår i den linjen är Siaröfortet.

  history/ vaxholms-yttre-befastningslinje/ 00-vaxholms-yttre-befatningslinje-sv.html
  (Vaxholms Yttre Försvarslinje, Sveriges historia)

Uppdatering:
Kompletterande text.

Annan historia relaterad till Sverige:

2 september, 2020

Myttingelinjen Värmdö: Svensk historia

• Ännu en dagsutflykt till ett gammalt försvarsfort. Myttingelinjen på Värmdö i Stockholm.

  history/ myttingelinjen-varmdo/ 00-myttingelinjen-sv.html
  (Myttingelinjen, Sveriges historia)

Uppdatering:
Kompletterande text.

Annan historia relaterad till Sverige:

August 17, 2020 Astronomy, meteor showers

In August we have the Perseid meteor shower, I did it a bit different this time. I used a GoPro camera:

• astronomy/astronomy-photo/ meteor-shower/ perseids/ perseids-2020/ perseids-2020.html
  (Perseid meteor shower, 2020)

Update:
Even more objects

Other meteor showers:

August 13, 2020 Astronomy: Project

• When I use my DSLR camera for time lapse movies I wear the shutter out, it only last for 200'000 exposure and a a one minute time lapse movie take 1800 shots. I need a fully electronic controlled shutter, can a GoPro camera be used for that ?

  astronomy/projects/ project-gopro-as-timelapse/ 01-project-gopro-as-timelapse.html
  (GoPro camera for time lapse of meteor showers)

Other astronomy projects:

Augusti 3, 2020 Historia, Slussen rivs

• Ni har säkert inte kunnat undvika att läsa om hus gamla slussen rivs i Stockholm för att ge plats åt Nya Slussen. Nu i dagarna (år 2020) kan man läsa i tidningarna hur de funnit rester av den näst äldsta slussen, Christopher Polhems sluss. Jag har under den slussen lagt in en länk som visar bilder på vad de funnit.

  history/sverige-stockholm-slussen/ sverige-stockholm-slussen-start.html
  (Gamla slussen rivs och Nya Slussen byggs, Stockholm)

Tragiskt att läsa att de beslutat riva de gamla viktiga historiska resterna av Polhems sluss, en kulturskatt som går förlorad för alltid.

Andra saker om Sveriges historia:

29 juli, 2020

Modellbåten Flamingo från Wentzel: Hobby

• När jag var omkring 9 år köpte min pappa mig min första modellbåt i trä. Den har nu efter 25 år på irrfärder hamnat hemma hos mig igen:

  vehicles/ models/ 02-wentzels-flamingo.html
  (Modellbåten Flamingo från Wentzel, hobby)

Update:
Har lagt till en lista på de modeller jag byggde, båtar, bil, flygplan.

Andra båtar i full skala:

July 12, 2020 Astronomy, comet

Suddenly we got a bright comet, the C/2020 F3 Neowise:

• astronomy/ astronomy-photo/ comets/ neowise-c2020-f3/ neowise-c2020-f3.html
  (Comet C/2020 F3 Neowise)

Update:
One more photo.

Other comets:

June 12, 2020 Cars

• I got a tips from a friend of a new place where they have car meetings, The Nut House.

  vehicles/ the-nut-house-2020/ the-nut-house-2020.html
  (The Nut House, car meeting in Sweden)

Other car meetings:

May 10, 2020 Astronomy: Project

• My old project with a Raspberry Pi2+ as an astroserver never worked very well, the process power from the computer was to weak. Now I do a new project of it with the new power full Raspberry Pi4 with 4 GB RAM:

  astronomy/projects/project-kstars-raspberrypi4/ 01-project-kstars-raspberrypi4.html
  (Project: Raspberry Pi4 as an astroserver)

Update:
Adding a GPS receiver.
First Light.

Other astronomy projects:

April 30, 2020 Home Theatre

• It's dark and winter now. I can't use my summer car and most days are cloudy so can't do my astronomy hobby either. What to do ? Restart my old hobby Home Theatre, of course !

  sound-image/ home-theatre-resurrection/ home-theatre-resurrection.html
  (Home Theatre resurrection, 2019)

  Update:
  More details about HTPC setup and MPC.
  Test with a Raspberry Pi4 as a HTPC.

Other Sound and Image:

April 25, 2020 Astronomy: Tutorial

• I have used the free image processing software Gimp earlier to processing my astrophotos. Didn't work very well with 32 bit floating point image files. But now with the latest ver 2.10 something has happened. Here is a tutorial for the first step, how to load the 32-bit images in Gimp:

  astronomy/ tutorials/ tutorial-gimp-astrophotography/ 01-tutorial-gimp-astrophotography-introduction.html
  (How to use Gimp for editing astrophotos)

Update:
Subtraction of background.
Added align R, G, B layer.
Separating stars and DSO.
Separating stars and DSO, alternative.
Correct image for Vignetting.

Other astronomy tutorials:

Mars 20, 2020 Astronomi, min nattbok

• Fantastiska tider, det är en klar natt igen. Ut med telekopet på balkongen, trimmar in justering och fokus. Denna natt tar jag bilder i riktningen söderut. Passar också på att berätta lite om ett av de nya projektet som går framåt och nu är i det stadiet jag kan testköra:

  .. lars-karlsson-night-balcony-work-20200320-se.html
  (Min nattbok om mina vedermödor ute i kylan)

Andra astronomi historier:

Mars 14, 2020 Astronomy, photography

One of the most beautiful objects on the sky is the planetary nebula M57, here is my photo of it:

• astronomy/ astronomy-photo/ planetary-nebulas/ m57/ m57-planetary-nebula.html
  (Messier 57, 2020)

Other Planetary nebulas:

February 210, 2020 Travel

• Once again we travel to the Canary Islands, this time the island Lanzarote:

  travel/ europe/ spain-lanzarote-2020/ 01-puerto-del-carmen.html
  (Lanzarote, Spain 2020)

Other travels in Europe:

January 13, 2020 Astronomy, calculation

• Calculate the minimum diameter of your filter without causing vignetting. Even the minimum distance off-axis adapter prism to optical axis:

  astronomy/ astronomy-calculations/ minimum-vignetting/ minimize-vignetting.html
  (Minimize vignetting calculator)

Other astronomy calculations:

January 10, 2020 Astronomy: Tutorial

• If you by mistake let the camera's auto rotation be enabled it cause you problem when doing astrophotography:

  astronomy/ tutorials/ tutorial-rotate-raw-files/ tutorial-rotate-raw-files.html
  (How to rotate raw-files)

Have you ever got the experience that your raw astrophotos are in portrait orientation and your software needs them to be in landscape orientation ? This tutorial is about a fix to that problem.

Other astronomy tutorials:

January 2, 2020 Astronomy

• With no dark nights during the summer it's time to do some work on the equipment. My old EQ6 mount needs some, I disassembling the mount and rebuilt it partly:

  astronomy/ projects/ project-eq6-dismantling-rebuilding/ 17-eq6-dismantling-rebuilding.html
  (EQ6 mount rebuilt)

  Update:
  After 3 months of bad weather I now had a clear sky. I could do more test of my rebuilt EQ6 mount and got good results. Look at the page 18 !

Other astronomy projects:

January 1, 2020 Astronomy

• What is it with our weather ? Clouds and rain every night. The motivation for all amateur astronomers go deep in the ground.

  The last days I have spent on the Gaia space satellite. It's a astrometry observatory with extremely high precision. Could it be used to do something interesting ? I have collected some information here and a simple test by me to start with:

  astronomy/ science-data/ science-data-gaia.html
  (Gaia data archive)

  You can use it as a tutorial how to use the Gaia data.

  Update:
  New calculations of histogram over the positions of nearby stars.

Other astronomy science data archives:

December 12, 2019 Astronomy, calculation

• Try my calculator based on Frank Drake's Equation:

  How many intelligent civilizations are out there in Milky Way ?

  astronomy/ astronomy-calculations/ drakes-equation/ drakes-equation.html
  (Frank Drake's Equation calculator)

Other astronomy calculations:

November 23, 2019 Travel

• 14 years ago it was an exiting day, I had read about a steam train. This day it will start from where I lived at that time and go to Katrineholm. Wonderful !

  travel/ sweden/ katrineholm-steam-train-2005/ 01-katrineholm-steam-train.html
  (Steam train from Stockholm to Katrineholm, 2005)

Other travels in Sweden:

November 8, 2019 Astronomy / seminar

• Seminars "The ALMA Fornax Cluster Survey" by Nikki Zabel.

  How does the galaxy cluster environment affect molecular gas and star formation? 2019
  (Institution of Astronomy, Stockholm's University)

Other speech, seminar and articles:

July 3, 2019 Travel, walks with old and new photos

• One old idea I have is to take old photos and then take new ones from the same place and compare. I have started with the island Riddarholmen in Stockholm. The old photography is from the 19th century. Much more complicated then I first thought, it will take long time, here is the beginning of the work:

  travel/ sweden/ old-and-new-photographs/ introduction-old-and-new-photographs.html
  (Old and new photography from Stockholm)

Other things about Swedish history:

June 7, 2019 Boats / Monalisa

• Big news! The anchor that belonged to Monalisa:

  vehicles/ everts-cruiser-monalisa/ everts-cruiser-monalisa-03.html
  (Photos of the anchor)

Other ships and boats:

May 19, 2019 Sound / Image

• Biograf (Cinema) Sländan Museum:

  sound-image/ cinema-slandan-museum/ cinema-slandan-museum.html
  (Biograf Sländan Museum)
• We had a visit to a camera flee market today, we was a bit early and found this when we waiting, a cinema machine museum.

Other things about sound and cinema:

27 januari, 2019

Nya kartor över fornlämningar: Fornhistoria

• Kartor för fornfynd, det är för dig som gillar att vara ute i naturen och leta efter vår spännande historia.

• Här finner du de nya kartorna:

  history/ sverige-fornlamningar-kartor/ fornlamningar-kartor-sv.html
  (Fornlämningskartor, Sverige)

Other history related in Sweden:

All other news: News.

New links:

Here I have collected new links that I found interesting.

Technology, Astronomy, Cars, Travels etc.

Mars 18, 2021 Astronomy Star Charts

I have updated the list of star chart links.

• Star Charts:

  links/ links-astronomy-starchart.html
  (Star Charts, link collection)

Mars 14, 2021 3D-printing Astronomy

My friend Lars found this interesting 3D-printing project.

3D-printing mount for Astrophoto:

• https://openastrotech.com/ (3D-print your own horse shoe mount, Open AstroTech)

Mars 12, 2021 Astronomy control software links

I have updated the list of computer control software for astronomy equipment.

• Astro computer control:

  links/ links-astronomy-controlsoftware.html
  (Astro Control software, link collection)

Mars 10, 2021 Travel and Astronomy

Astro-tourism, a growing tourist travel area.

• Astro Tourism:

  links/ links-astronomy-astrotourism.html
  (Astro Tourism, link collection)

I have primarily chosen places that I can reach from Sweden within 6 hours by air. Most of them are in Spain.

December 8, 2020 Astronomy education

• Follow David Butler's fantastic Video Books:

  links/ links-astronomy-education.html
  (Astronomy Education, Links)

Overview of the links:

• Links

Must do stuff:

Technology, Astronomy, Cars, Travels etc.

(look carefully that it has not been canceled or has a changed date)

May, 2020 Astronomy

• Comet C/2020 F3 Neowise visit us:

  http://www.aerith.net/comet/ catalog/2020F3/ 2020F3.html
  (C/2020 F3 Neowise, Seiichi Yoshida)

• Comet ATLAS: Will it Become a Naked-Eye Object? Yes we got to see ot from our living room, first night it had a magnitude of 1.5. There where two nights with enough clear sky for us to catch some photos.

  astronomy/astronomy-photo/comets/ neowise-c2020-f3/ neowise-c2020-f3.html
  (C/2020 F3 Neowise, photo from our balcony)

Föredrag: (Stockholm, Sverige)

This is only for you who live in Stockholm, Sweden or want to travel and make a visit here.

De flesta av de här föredragen hålls i Stockholm. Vanligtvis är de på svenska men ibland på engelska. Läs noga på deras hemsida så att det inte blivit inställt eller flyttat.

Området är naturvetenskap.

2020 Visning / Föredrag

• Visningar av Alba Nova teleskopet:

  http://www.astro.su.se/ om-oss/ evenemang/ teleskopvisningar
  (Alba Nova teleskopet, Stockholms universitet)

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