Astrofriend's homepage
Search Astrofriend's homepage:

Valid CSS!

All pages shall now have been validated

Info Cookies (Kakor) / GDPR


Twitter @AstrofriendLars

Follow Astrofriend

Latest News

Advertisement /

Page Visitors


Last update:

November 14, 2021

Weather forecast:

Weather forecast Sweden


Väder alarm

Advertisement / Annons:

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.

Welcome to my home !

Astrofriend's homepage


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



Here I have collected news I found interesting.

Technology, Astronomy, Cars, Travels etc.

November 14, 2021 Sweden Historia, Nya Slussen byggs upp

Andra saker om Sveriges historia:

Karl Johan Slussen i Stockholm

October 28, 2021 Travel

Other travels in Europe:

Crete, Greek, 2021

October 2, 2021 Astronomy: Project

3D-printing the focuser chassi, page 10
Second design of focus chassi, page 10
Worm gear, page 11
More details added to the new focus chassi, page 9 to 10
Test print module 0.5 mm and 1.0 mm gears
Open the focuser and look how to implement the rack & pinion

Other astronomy projects:

3" focuser: 3D-Printing rack & pinion gears

September 30, 2021 3D printer

Other 3D Printer and CAD projects:

3D printer, nozzle temperture

September 27, 2021 3D printer

Other 3D Printer and CAD projects:

3D printer, horizontal calibration

September 14, 2021 Sweden Historia, S/S Masilia ?

Andra saker om Sveriges historia:

Pråmen Carrier 2 Slussen

September 6, 2021 Astronomy, observatory site

Other observatory sites:

Börje's observatory, 2021

September 1, 2021 Bilskrotar kartor:

  • För dig med gammal klassisk bil, när reservdelarna inte finns att köpa nya längre så blir man hänvisad till bilskrotarna. Jag har kompletterat mina tidigare listor med kartor för att lättare finna dom:

    vehicles/ bilskrotar/ bilskrotar-sverige.html
    (Bilskrotar Sverige)

Övrigt skrotbilar:


August 18, 2021 Cars, Chrysler Crossfire repair:

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Jack location point

Augusti 17, 2021 Astronomy, photography

Perseid meteor shower 2021, UFO

UFO-like phenomena captured during Perseid meteor show reconnaissance 2021.

Other Astronomy photo:

August 15, 2021 Travel Sweden

Other travels in Sweden:

Höga Kusten, Sweden 2021

August 10, 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)

New power battery cables (page 10)
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:

Projects: HEQ5 as a portable mount

June 23, 2021

Stockholm's Harbors: Swedish history

Other history related about Sweden:

Stockholm's harbors

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:

Projects: HEQ5 as a portable mount

May 13, 2021 Astronomy: Project

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:

Projects: Pentax 645 300 mm ED f/4 lens

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)

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:

3D CAD: EQ6 Pad

May 5, 2021 Astronomy, observatory site

Uppsala telescope in Australia.

Other observatory sites:

Uppsala old observatory, 2021

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:

Other Open Clusters:

M39 Open Cluster, 2021

April 24, 2021 Cars, Chrysler Crossfire repair:

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Battery current drain

April 22, 2021 3D printer

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:

3D printer, assembling and setup

April 15, 2021 Astronomy: Project

Mount and pier
Welding in aluminum
3D-printed focuser

Other astronomy projects:

Lars B's projects

April 12, 2021 Cars, Chrysler Crossfire repair:

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Spring rear

April 7, 2021 Astronomy: Lens data base

Other astronomy tutorials:

Data base: Lenses with focus motor that works for astrophotolens

April 3, 2021 3D-printing: CAD

Other about 3D-printing and CAD:

3D CAD: Viewfinder cover, Canon EOS DSLR (6D)

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:

One more photo 23/4-21.

Other Novas:

Nova V1405 Cas

Mars 23, 2021 Astronomy

Gösta Gahm

Gösta Gahm, 1942 - 2020 professor emeritus of astronomy

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

Mars 20, 2021 Astronomy: Project

Other astronomy projects:

Projects: Vignetting of my lenses, Pentax 645 300 mm ED f/4

Mars 8, 2021 Astronomy, observatory site

Other observatory sites:

Tamm's Observatory, 2021

February 11, 2021 3D-printing: CAD

180 teeth pulley
Front bracket

Other about 3D-printing and CAD:

3D CAD: Motor focuser bracket

February 15, 2021 Astronomy: Project

Implement of AstroEQ ?

Other astronomy projects:

Project: EQ6 periodic error

February 1, 2021 Astronomy: Project

Other astronomy projects:

Project: dew heater

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)

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:

Project_ 300mm setup on EQ6 mount

29 januari, 2021 Sweden Resor till sjöss

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

Other history related:

Fartyget S/S Sylvia

January 22, 2021 3D-printing: CAD

Other about 3D-printing and CAD:

3D CAD: Compas stand

January 9, 2021 3D CAD

New 180 teeth GT2 Pulley.

Other 3D Printer and CAD projects:

3D CAD: making drawings for GT2 pulleyes to lens focuserder

December 27, 2020 3D printing

Other 3D Printer and CAD projects:

3D print: adapter to 90 degree angled polar finder

December 23, 2020 Astronomy

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

All pages are now translated and online.

Other observatory sites:

The observatory in Uppsala in todays condition. Photographer unknown

28 december, 2020 Sweden 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)

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:

My father's adventures at sea, 1937 - 1945

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.

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Wheels and tires

15 november, 2020 Sweden

Befästningslinjen Södra fronten: Svensk historia

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

Annan historia relaterad till Sverige:

Befästningslinjen Södra Fronten

21 Oktober, 2020 Sweden 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:

Andra meteoritkratrar:

Meteorite craters, Dellensjöarna Sweden, 2006

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 !

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

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Replacing the crankshaft sensor

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:

The village Röttle, Sweden 2007

2 september, 2020 Sweden

Vaxholms Yttre Befästningslinje: Svensk historia

Kompletterande text.

Annan historia relaterad till Sverige:


2 september, 2020 Sweden

Myttingelinjen Värmdö: Svensk historia

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:

Even more objects

Other meteor showers:

Perseids meteor shower, 2020

August 13, 2020 Astronomy: Project

Other astronomy projects:

GoPro camera as a timelapse camera for meteor showers

29 juli, 2020 Sweden

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)

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

Andra båtar i full skala:

Modellbåten Flamingo från Wentzels

July 12, 2020 Astronomy, comet

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

One more photo.

Other comets:

Comet C/2020 F3 Neowise, 2020

June 12, 2020 Cars

Other car meetings:

Car meeting, The Nut House, 2020

May 10, 2020 Astronomy: Project

Adding a GPS receiver.
First Light.

Other astronomy projects:

Raspberry Pi4 as an astroserver

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)

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

Other Sound and Image:

Home Theatre resurrection, 2019

April 25, 2020 Astronomy: Tutorial

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:

Tutorial: Gimp for astrophotography

Mars 20, 2020 Svenska 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:

Projekt: Find flat cal points

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:

Other Planetary nebulas:

Planetary nebula M57, 2020

February 210, 2020 Travel

Other travels in Europe:

Lanzarote, Spain, 2020

January 10, 2020 Astronomy: Tutorial

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:

Tutorial: How to rotate raw-files

January 2, 2020 Astronomy

Other astronomy projects:

Summer project, dismantling the EQ6 mount and rebuilding

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.

    New calculations of histogram over the positions of nearby stars.

Other astronomy science data archives:

Gaia data archive

December 12, 2019 Astronomy, calculation

Other astronomy calculations:

Frank Drake's Equation calculator

November 23, 2019 Travel

Other travels in Sweden:

Steam train from Stockholm to Katrineholm, 2005

November 8, 2019 Astronomy / seminar

Other speech, seminar and articles:

Seminar: How does the galaxy cluster environment affect molecular gas and starformation ? by Nikki Zabel

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:

Old and new photography from Stockholm

June 7, 2019 Boats / Monalisa

Other ships and boats:

Evert's mahogany cruiser Monalisa

May 19, 2019 Sound / Image

Other things about sound and cinema:

Biograf (Cinema) Sländan Museum, 2019

27 januari, 2019 Sweden

Nya kartor över fornlämningar: Fornhistoria

Other history related in Sweden:

All other news: News.

Gånggrift Hallarör i Västergötland
Go Back to content

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.


Mars 14, 2021 3D-printing Astronomy

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


Mars 12, 2021 Astronomy control software links

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


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.

Andromeda M31 POSS-I

December 8, 2020 Astronomy education


Overview of the links:

Go Back to content

Must do stuff:

Technology, Astronomy, Cars, Travels etc.

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

May, 2020 Astronomy

Seiichi Yoshida's home page
Go Back to content

Föredrag: (Stockholm, Sverige) Sweden

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.

2021 Visning / Föredrag

Go Back to content

Advertisement / Annons: