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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:

• NewsHighlights on Astrofriend's homepage, see also left column Latest News
• New linksInteresting information NEW Mars 2022 !
• Must do stuffWhat makes your life valuable NEW April 2022 !
• Speech nature science, Föredrag naturvetenskap(most speeches in Swedish)

News:

Here I have collected news I found interesting.

Technology, Astronomy, Cars, Travels etc.

July 30, 2022 Travel Gotland in Sweden

• It's summer now and then we travel around in Sweden. This time we visit the beautiful island Gotland. I have been at that island three times before, but always exiting. My girlfriend has a special mission, she wants to find traces of her ancestors:

  travel/ sweden/ gotland-2022/ 01-gotland-2022.html
  (Visiting the island Gotland in Sweden, 2022)

Other travels in Sweden:

29 juli, 2022 Historia, Stockholm

• I Stockholm finns många spännande platser att undersöka. Ett av dom är Västra Stambanans gamla dragning mellan Liljeholmen och Södra Station på Södermalm. Den sträckan lades ned år 1929 då tågtrafiken flyttade till nya Årstabron.

  history/ vastra-stambanan/ 01-vastra-stambanan-sv.html
  (Västra Stambanan, Stockholm)

  Uppdatering:
  Äldre bilder från lokverkstaden i Liljeholmen tillagda
  Många historiska bilder över Liljeholmens tågbro har lagts till
  Kompletterat med information om ånglok vid Liljeholmen
  Liljeholmens tre stationshus tillagda
  Godsterminalen tillagd
  Kompleterande bilder från 2022
  Området omkring Zindensdamm tillagda
  Södra Station tillagd

Andra saker om Sveriges historia:

July 8, 2022 Home Theatre

• This week I listening to the hard rock cover band Sershen & Zarítskaya.

  https://www.youtube.com/ channel/ UCFPzKZg-By8_DtBJiEDLcJw
  (Sershen & Zarítskaya, YouTube)

Other Sound and Image:

July 7, 2022 Home Theatre

• Our remote control for the Television got broke. I took it apart to investigate what was wrong and then repaired it.

  sound-image/ hitachi-remote-repair/ hitachi-remote-repair.html
  (Hitachi RC 43140 remote repair)

Other Sound and Image:

6 juli, 2022 Historia, Galgbackar

• Under ett par vandringar i Stockholms Stad med omgivningar har vi undersökt de platser där folk avrättats i gångna tider, Stockholms galgbackar.

  history/ galgbackar-stockholm/ 01-galgbackar-stockholm-sv.html
  (Avrättnings och galgbackar i Stockholm)

  Uppdatering:
  Hammarby galgbacke, sida 7

Andra saker om Sveriges historia:

July 5, 2022 Travel Europe

• We started drawing plans for our summer trip a couples of weeks ago. A round trip in Northern Europe by buses and trains. But we have already changed our plans and start with a ferry:

  travel/ europe/ rostock-amsterdam-2022/ 01-rostock-amsterdam.html
  (Rostock - Amsterdam, Northern Europe 2022)

Other travels in Europe:

July 4, 2022 3D printer

• The knob's scale rings of the gas oven has broken. Very difficult to find a new one to the IGF Copenhagen gas oven. I designed a new one to be 3D-printed:

  3d-printing/igf-copenhagen-handle/01-igf-copenhagen-handle.html
  (IGF Copenhagen gas oven knob's scale ring)

Other 3D Printer and CAD projects:

June 29, 2022 Bicycle renovation:

• With increasing gas prizes it's time to take a look at my old bicycle:

  vehicles/ my-cars/ 28inch-bicycle-street-racer/ 01-28inch-bicycle-street-racer.html
  (28" street and forest racer)

My vehicles:

21 juni, 2022 Fartyg / båtar

Lastfartyget Najade passerar Årstaviken, Stockholm 2022:

Ett ur vårt tycke alldeles för stort fartyg för att få plats i den lilla Hammarbyslussen. Fartyget verkar vara olastat och har nu destinationen Luleå. Min kamrat Hans berättade att hon varit i Västerås och lastat av. Där finns ett stort värmekraftverk, kanske det var bränsle till det. Hon är 105 meter lång och Hammarbyslussen kan klara upp till 115 meters längd.

Other ships and boats:

June 8, 2022 Cars, Chrysler Crossfire:

• I'm preparing to upgrade the rear chassi of my car. Most important is the rubber bushings that is too soft:

  vehicles/ my-cars/ chrysler-crossfire/ upgrading-rear-chassi/ 01-upgrading-rear-chassi.html"
  (Upgrading the rear chassi)

Other DIY repair tips for Chrysler Crossfire (Mercedes):

June 3, 2022 Astronomy: Astronomy Project

• Now when I almost finished the mechanical construction of my push pull screw focuser I must plan for the stepper motor controller. I need a hardware driver and control logic that can use INDI drivers:

  astronomy/ projects/ project-motor-focus-driver/ 01-project-motor-focus-driver.html
  (Project: Stepper motor driver)

Update:
Tools for develop, page 2

Other astronomy projects:

June 3, 2022 Astronomy: Astronomy Project

• Today I try to do some radical about my friction coupled focuser. 3D-Printing rack & pinion gears (and later push pull screws):

  astronomy/ projects/ project-focus-friction/ project-focus-friction.html
  (Project: Focus friction coupler)

Update:
Installation of timing belt, page 15
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:

June 2, 2022 Travel Sweden

• Steam trains are always exiting, I have done two travels with a steam train from Stockholm City to Nynäshamn. Both of them at Christmas. One more visit to the train museum at Nynäshamn:

  travel/ sweden/ nynashamn-steamtrain-2005-2009/ 01-nynashamn-steam-train.html
  (From Stockholm City to Nynäshamn by Steam train, Sweden from 2005 to 2009)

Other travels in Sweden:

10 maj, 2022 Nöjen i Stockholm

Restauranger:

• 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

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 ones 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)

  Update:
  STL file download, page 4 bottom

Other DIY repair tips for Chrysler Crossfire (Mercedes):

30 april, 2022 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

April 29, 2022 Boats / Monalisa

• Big news! I have photos of Ellinor, a sister boat to Monalisa:

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

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

Other ships and boats:

April 22, 2022 Cars, Chrysler Crossfire lights:

• The car's license plate lights are aged and with a lot of cracks. It must be replaced:

  vehicles/ my-cars/ chrysler-crossfire/ license-plate-light/ 01-license-plate-light.html
  (License plate light replacement)

  Update:
  Fine trimming the frame of the LED light

Other DIY repair tips for Chrysler Crossfire (Mercedes):

April 12, 2022 Cars, Chrysler Crossfire interior:

• To get the boring grey interior of the car I try to pimp it up with blue stripes:

  vehicles/ my-cars/ chrysler-crossfire/ interior/ 06-chrysler-crossfire-interior.html
  (Interior: Blue stripes)

Other DIY repair tips for Chrysler Crossfire (Mercedes):

7 april, 2022 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:
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:

April 6, 2022 Cars, Chrysler Crossfire interior:

• Today I replaced the old boring grey rubber carpets in the car, carbon black with a blue line:

  vehicles/ my-cars/ chrysler-crossfire/ interior/ 05-chrysler-crossfire-interior.html
  (Interior: Carbon black carpets)

Other DIY repair tips for Chrysler Crossfire (Mercedes):

April 2, 2022 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:
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:

28 mars, 2022

Mörka observationsplatser: Astronomi

• I södra Stockholm på ön Torö är man långt från stadens ljus. Här är några foton från en parkering i naturreservatet.

• Örudden på Torö:

  astronomy/ observationsplatser/ orudden/ observationsplats-orudden.html
  (Observationsplatser Örudden Torö, Stockholm)

Andra observationsplatser i Stockholm:

All other news: News.

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:

• astronomy/ meteorite-craters/ impacts.html
  (Meteorite crater Västra Styran, 2022)

It's no 10 on the map.

other meteorite craters:

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

• I installed the new wheels I bought a while ago, the rear wheels and tires:

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

Other DIY repair tips for Chrysler Crossfire (Mercedes):

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)

Update:
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:

Mars 13, 2022 Astronomy: Project

• My pier I built many years ago was designed to take the EQ6 mount. Now I adapt it to also handle the smaller HEQ5 mount:

  astronomy/ projects/ project-pier-mount/ project-pier-mount.html
  (Project: Adapt pier to HEQ5 mount)

Update:
HEQ5 mount on pier (page 6)

Other astronomy projects:

Mars 10, 2022 Astronomy: Tutorial

• When doing astrophotography it's very important to have a clean sensor. No dust or drying stains on it.

  Update:
  New kind of spatula (page 2)

  Warning:
  This is how I do it, maybe not the best way and the camera can be destroyed. The interior of the camera is very fragile and sensitive:

  astronomy/ tutorials/ tutorial-cleaning-sensor/ 01-tutorial-cleaning-sensor.html
  (Cleaning the camera sensor)

Other astronomy tutorials:

Mars 4, 2022 Astronomi, Historier

• Återigen går jag upp på piskbalkongen, det har lovats klar stjärnhimmel i ett par dagar framöver.

  astronomy/ astronomy-stories/ lars-karlsson-night-balcony-work/ lars-karlsson-night-balcony-work-20220304-se.html
  (En natt på piskbalkongen)

Andra astronomihistorier:

January 29, 2022 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:
Setup Raspberry as a Hotspot (page 11)
Offset the focus position (page 8 bottom)
Adding a GPS receiver.
First Light.

Other astronomy projects:

January 28, 2022 Astronomy: Project

• When living on a high light pollution place it's important to be able to bring the equipment out on the country side and get some darkness. Then weight and power source are important. Here I have my new battery, a Lithium battery:

  astronomy/ projects/ project-astro-server-and-powerunit/ 41-astro-server-and-powerunit.html
  (Project: Lithium battery power)

Other astronomy projects:

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:

• astronomy/ astronomy-photo/ double-stars/ big-dipper-stars/ big-dipper-stars.html
  (Seven stars in Big Dipper)

Other stars:

January 7, 2022 Astronomy, comet

The comet Atlas C/2019 L3:

• astronomy/ astronomy-photo/ comets/ atlas-c2019-l3/ atlas-c2019-l3.html
  (Comet C/2019 L3 Atlas)

Other comets:

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:

January 11, 2022 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)

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

Other astronomy tutorials:

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:

• astronomy/ astronomy-photo/ nebulas/ m42/ m42-orion-nebula.html
  (M42 Orion nebula, 2021)

Other Nebulas:

December 1, 2021 Travel Europe

• Fuerteventura is one of the Canary Islands, a place I have never been at before. Now in November we got the chance to visit it:

  travel/ europe/ spain-fuerteventura-2021/ 01-fuerteventura.html
  (Fuerteventura, Spain 2021)

Other travels in Europe:

November 30, 2021 Astronomy, observatory site

• Fuerteventura was one of the islands of Canary islands that I hadn't visit earlier. I have read about it dark places and now I got a chance to visit them. This is from our visit of these dark places:

  astronomy/ observatory-sites/ fuerteventura-astronomy-park/ fuerteventura-astronomy-park.html
  (Fuerteventura Astronomy park, 2021)

Other observatory sites:

November 14, 2021 Historia, Nya Slussen byggs upp

• Nu är det november år 2021. Vi har idag en fin klar himmel och solen tränger ned till oss. Vi utnyttjar dagen till att åka in till Slussen för att se hur bygget går, senaste bilderna längst ned på sidan.

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

Andra saker om Sveriges historia:

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

• During Corona times there hasn't been very much traveling, but now in August we took a cruise along the Swedish coast. From Stockholm to Höga Kusten:

  travel/ sweden/ ms-symphony-stockholm-harnosand-hogakusten-2021/01-ms-symphony-stockholm-harnosand-hogakusten-2021.html
  (Höga Kusten [High Coast], Sweden 2021)

Other travels in Sweden:

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:

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 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:

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)

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:

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 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:

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:

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:

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:

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:

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:

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 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 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:

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 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.

• https://www.dpreview.com/ news/ 5938566942/ japan-sends-a-modified-pentax-300mm-f4-lens-into-space-aboard-its-kitsune-6-microsatellite (Japan sends a modified Pentax 300mm F4 lens into space aboard its Kitsune 6 microsatellite, DPreview)

Mars 12, 2022 3D-Printing, Astronomy

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

• https://www.thingiverse.com/ thing: 1987284 (Bahtinov mask generator, Bot-ork)

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.

• Optimizing Your Imaging System for Your Guiding Performance:

  https://www.youtube.com/ watch?v= vvJYCM4F8G0
  (When is Guide Performance good enough ?, James Lamb)

February 9, 2022 Mechanical ideas

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

• JWST Mirror Actuators!:

  https://www.youtube.com/ watch?v= 5MxH1sfJLBQ
  (JWST Mirror Actuators are AMAZING!, Breaking Taps)

12 January, 2022 Historia Sverige

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:

• https://www.youtube.com/ watch?v= neCPqqlZtWc (Rysshärnngarna, Global Pictures / Roger Persson, YouTube)

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 !

• Make Your Own Smart Telescope:

  https://www.youtube.com/ watch?v= 0JdtL950RjQ
  (Make Your Own Smart Telescope, Lazy Geek)

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 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)

April, 2022 Astronomy

• Comets to view 2022:

  https://skyandtelescope.org/ astronomy-news/ comets-to-view-in-2022/
  (Comets to view 2022, Sky and Telescope)

• 8 Deep-Sky Targets for Galaxy Season:

  https://astrobackyard.com/ 8-deep-sky-targets-galaxy-season/
  (8 Deep-Sky Targets for Galaxy Season, AstroBackyard)

• Comet C/2020 F3 Neowise visit us:

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

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.

2022 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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