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Last update:

May 16, 2022

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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.

Welcome to my home !

Astrofriend's homepage

Since 2002

Celebrating 20 years !


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



Here I have collected news I found interesting.

Technology, Astronomy, Cars, Travels etc.

May 16, 2022 Astronomy: Astronomy Project

Assembling the parts, page 14
Installing focuser drawing tube's roller bearings, page 13
Stabilization of the focuser draw tube, page 13
New design with push pull screws, page 12
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 Old design

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

10 maj, 2022 Sweden Nöjen i Stockholm


  • Tidigare tipsade jag om takpubar och restauranger, mycket trevligt men inte billigt. Nu har jag kompletterat med en lista på restauranger där man kan äta god mat utan att det kostar väldigt mycket:

    pleasure/ restauranger/ restauranger.html
    (Listor över restauranger i Stockholm med god mat och överkomliga priser)

Andra nöjen: Nöjen i Stockholm

Restauranger i Stocklm med god mat och överkomliga priser

May 9, 2022 Cars, Chrysler Crossfire lights:

  • By accident I destroyed my turn signal on the fender. When I searched for a new I found there where no to find, new or used. I repaired the old but later I must have a better solution. Here I design a 3D-printed adapter to mount more modern E certified turn signals:

    vehicles/ my-cars/ chrysler-crossfire/ turn-signals/ 01-turn-signals.html"
    (Turn signals)

    STL file download, page 4 bottom

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Turn signal adapter 3D-printed

May 8, 2022 Astronomy: Astronomy Project

Other astronomy projects:

Stepper motor driver

30 april, 2022 Sweden Nöjen i Stockholm

Takpubar och restauranger:

  • Nu till årets sommar kan vi nästan koppla av från Covidbekymren. Vi vågar gå ut igen och träffa folk med viss försiktighet. Sommarens projekt blir att besöka några av Stockholms takpubar och restauranger. De har blivit väldigt populära på senare år. Här har jag listat de mer kända och gjort en karta så ni hittar dit:

    pleasure/ takpubar/ takpubar.html
    (Listor och kartor över takpubar och restauranger i Stockholm)

Andra nöjen: Nöjen i Stockholm

TAK, takpub i Stockholm

April 29, 2022 Boats / Monalisa

Now I'm in contact with Stefan, the owner of Monalisa's sister boat Ellinor, page 5

Other ships and boats:

Evert's mahogany cruiser Monalisa

April 22, 2022 Cars, Chrysler Crossfire lights:

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: License plate light

April 12, 2022 Cars, Chrysler Crossfire interior:

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Pimp the car with blue stripes

7 april, 2022 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)

Film från Hamburg hamn år 1938, se M/S Canton när Hamburg hamn angörs
Krister har kommit med ny information om Violett
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

April 6, 2022 Cars, Chrysler Crossfire interior:

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Carbon black carpets

April 15, 2022 Cars, Chrysler Crossfire:

Toe-in angle meter (page 3)

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Wheels angles

April 2, 2022 3D printer

Auto calibration and probe offset (page 13)
Replacing the nozzle heater (page 18)
Wind screen (page 17)
P.I.D. optimizing (page 15)
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

Mars 31, 2022 Cars, Chrysler Crossfire repair:

Spring pad shims (page 3)

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Spring rear

28 mars, 2022 Sweden

Mörka observationsplatser: Astronomi

Andra observationsplatser i Stockholm:

All other news: News.

Observationsplats Örudden på Torö

October, 2022 Astronomy, Impact structures (meteorite craters)

In Mars 2022 I passed close to the lake Västra Styran. I know I have read about it somewhere that it's maybe an old meteorite crater:

It's no 10 on the map.

other meteorite craters:

Meteorite craters, Västra Styran Sweden, 2022

Mars 25, 2022 Cars, Chrysler Crossfire wheels/tires:

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: New rear Wheels and tires

Mars 19, 2022 Cars, Chrysler Crossfire repair:

Other DIY repair tips for Chrysler Crossfire (Mercedes):

Chrysler Crossfire: Swaybar bushings

Mars 17, 2022 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-heq5/ 01-heq5.html
    (Project: HEQ5)

Making EQDirect cable (page 18)
Putting wheels on the box (page 17)
Transport box (page 17)
Brackets: temperature sensor, spirit level and stepper motor (page 16)
Raspberry PI4 bracket (page 15)
Redesign of mount head details (page 14)
Making my tripod to a low rider (page 13)
Rowan Belt Modification kit (page 12)
Tweaking auto guide parameters (page 11)
New power battery cables (page 10)
Reducing cable clutter, shorten GPS cable (page 7)
Power consumption (page 9)
Setup of GPS NMEA (page 8)
Setup of GPSD (page 7)
Succeeded to run Astroberry (page 6)
Setup the Raspberry system
Installing 300 mm astrophoto equipment on HEQ5 (page 4)
Install a better power connector (page 3)
Change from 9-pol D-sub to RJ45 standard (page 2)

Other astronomy projects:

Projects: HEQ5 as a portable mount

Mars 13, 2022 Astronomy: Project

HEQ5 mount on pier (page 6)

Other astronomy projects:

Projects: Adapt pier to HEQ5 mount

Mars 10, 2022 Astronomy: Tutorial

Other astronomy tutorials:

Tutorial: Cleaning the camera sensor

Mars 4, 2022 Sweden Astronomi, Historier

Andra astronomihistorier:

Två nätter på piskbalkongen

Februari 28, 2022 Sweden Astronomi, Historier

Andra astronomihistorier:

Två nätter på piskbalkongen

February 21, 2022 Astronomy

Other astronomy tutorials:

pixel size matching

February 26, 2022 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. Later I switched over to my new Raspberry controller:

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

Transport box (page 14)
Optimize auto focus (page 13)
New update of Ekos auto focus driver (page 13)
Aperture and deformed stars (page 12)
Eliminate tilt (page 11)
Measure tilt (page 11)
Analyze tilt (page 11)
Optical analyze (page 10)
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

January 29, 2022 Astronomy: Project

Setup Raspberry as a Hotspot (page 11)
Offset the focus position (page 8 bottom)
Adding a GPS receiver.
First Light.

Other astronomy projects:

Raspberry Pi4 as an astroserver

January 28, 2022 Astronomy: Project

Other astronomy projects:

Projects: Lithium battery power

January 16, 2022 Astronomy, Seven stars in Big Dipper, part of constellation Great Bear

Tonight I have problem which object on the heaven I wanted to take photo of. Then I saw that I had the constellation Great Bear outside the window. Why not take photos of the seven stars that built the Big Dipper which is a part of the Great Bear ? Afterwards I can analyze the images and see what's more there, sounds a bit exiting to me:

Other stars:

Seven stars in constellation Big Dipper, credit CdC

January 10, 2022 Astronomy tutorial: Flat calibration

Design off second cylinder that holds diffuser 2 (page 10)
3D-Printed first cylinder that holds second diffuser (page9)
Added a typical white flat taken with a color camera (page 7)
3D-printing of a LED stripe holder (page 8)
Did some more test how to get a more even flat

Other astronomy tutorials:

Flat calibration

January 7, 2022 Astronomy, comet

The comet Atlas C/2019 L3:

Other comets:

Comet C/2019 L3 Atlas, 2022

January 5, 2022 Astronomy tutorial: Ekos Sequencer

  • Included in the KStars is the Ekos. Ekos control the devices in your astroequipment. Included in this is a sequencer, a tool where you can hold your evening objects and the sequencer pick them up one by one in the most useful order. This is something new to me and all these advanced function is operated by the tiny Raspberry processor:

    astronomy/ tutorials/ tutorial-ekos-sequencer/01-tutorial-ekos-sequencer
    (Ekos Sequencer)

Other astronomy tutorials:

Ekos sequencer

January 2, 2022 Astronomy: Project

Other astronomy projects:

Projects: Pentax 645 lens system light leakage

January 11, 2022 Astronomy: Lens data base

Added Canon 75-300 III
Added Yongnuo 50mm f/1.8
Added Tamron 28-300 mm lens

Other astronomy tutorials:

Data base: Lenses with focus motor that works for astrophotolens

December 30, 2021 Astronomy, photography

With my new equipment I'm ready to take new astrophotos. With a 300 mm lens it's on the limit to be called a wide angle image:

Other Nebulas:

M42 Orion nebula, 2021

December 7, 2021 Astronomy, comet

First astrophoto of the season 2021/22, the comet Leonard C/2021 A1:

Other comets:

Comet C/2021 A1 Leonard, 2021

December 1, 2021 Travel

Other travels in Europe:

Fuerteventura, Spain 2021

November 30, 2021 Astronomy, observatory site

Other observatory sites:

Fuerteventura Astronomy park, 2021

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

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 15, 2021 Travel Sweden

Other travels in Sweden:

Höga Kusten, Sweden 2021

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 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 15, 2021 Astronomy: Project

Mount and pier
Welding in aluminum
3D-printed focuser

Other astronomy projects:

Lars B's projects

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

February 11, 2021 3D-printing: CAD

180 teeth pulley
Front bracket

Other about 3D-printing and CAD:

3D CAD: Motor focuser bracket

February 1, 2021 Astronomy: Project

Other astronomy projects:

Project: dew heater

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 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

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

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:


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

June 12, 2020 Cars

Other car meetings:

Car meeting, The Nut House, 2020

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

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 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

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
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New links:

Here I have collected new links that I found interesting.

Technology, Astronomy, Cars, Travels etc.

Mars 16, 2022 Astronomy, lens

Japan must have looked at my site, they are now sending a Pentax 300mm f/4 lens to space. I use an older variant in my 300 mm project.

Pentax 645 300 ED IF f/4

Mars 12, 2022 3D-Printing, Astronomy

Found this Batinov mask generator, I have never test it but looks interesting.


February 21, 2022 Mechanical ideas

Found this YouTube video when I search for information. He do a deep in analyze of auto guiding in combination with different telescopes.


February 9, 2022 Mechanical ideas

Maybe something that can give you ideas how to construct details with your 3D-Printer.


12 January, 2022 Historia Sverige Sweden

Om du är intresserad av svensk historia och bor på östkusten är denna dokumentär riktigt intressand för dig. Handlar om Ryssarnas härjningar på svenska östkusten år 1719:


January 12, 2022 Astronomy Smart Telescope

You maybe only do visual observations because you feel it's too complicated to do astrophotographing. Then this instructions video could be of interest for you, or just because Lazy Geek do a lot of nice videos in the Astronomy area. Have one hour of pleasure !


Mars 18, 2021 Astronomy Star Charts

I have updated the list of star chart links.


Mars 10, 2021 Travel and Astronomy

Astro-tourism, a growing tourist travel area.

Andromeda M31 POSS-I

December 8, 2020 Astronomy education


Overview of the links:

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Must do stuff:

Technology, Astronomy, Cars, Travels etc.

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

April, 2022 Astronomy

Seiichi Yoshida's home page
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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.

2022 Visning / Föredrag

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