Saturday, September 15, 2018

Comet 21P Giacobini-Zinner and Messier M35 : astrophotography highlight


An astrophotography highlight this morning : Comet 21P Giacobini-Zinner together with Open Star Cluster Messier M35. The "Green Comet" was passing in front of M35, an open star cluster in the constellation Gemini. The picture below shows also star cluster NGC2158 en IC2157.
The picture was taken with Nikon D7500 on TLAPO80/480 f/6. Editing was done using CS4.


It's interesting to see how "fast" the Green Comet is moving against the stars. Below picture was taken this morning with a time difference of 1hour.


Thursday, September 13, 2018

Alrediph Delta Cephei the prototype standard candle

Alrediph or Delta Cephei, is the prototype star of the class of  Cepheid variables and located in the constellatioin Cepheid. Its apparent visual magnitude at minimum is 4.34 and at maximum 3.51, changing in a regular cycle of about five days and nine hours. Its variations in brightness is imporatant becayse there’s a relationship between the length of each beat and the star’s brightness. Astronomers can use that relationship to measure the star’s distance. That makes them valuable tools or standard candles for helping to measure the scale of the universe.


Wednesday, September 12, 2018

Stock 7 and Stock 23



Two pictures of open starclusters Stock 7 (stacked) and Stock 23 (sigle shot).
Stock 7is located near the Heart Nebula and the Fishhead Nebula.
All pictures are taken using refractor TLAPO 80/480 f/6 with Nikon D7500. Stacking was done with DeepSkyStakker and editing with CS4.






Triangulum Galaxy Messier M33


In the constellation Triangulum and on a distance of 3 million light years from Earth the Triangulum Galaxy (Messier M33) can be observed.
This picture is the result of stacking 17 pictures each 30s using Nikon D7500 on TLAOP80/480 f/6. Stacking was done using DeepSkyStacker with pictures of DNG format. Final editing with CS4.


21P Giacobini-Zinner

I'm really satisfied as last night it was finally possible to capture Comet 21P Giacobini-Zinner. The comet was located a couple of degrees south of Messier M37 in constellation Auriga. The picture below is a single shot of 30s using Nikon D7500 on TLAPO80/480 f/6; editing done using CS4.




Saturday, September 8, 2018

My new learning applied on Messier M8 Lagoon Nebula

Narrowing RGB for both curves as levels

As mentioned in my earlier blog, narrowing individual RGB for both curves as levels in CS4 gives much better results. Using a stacked picture of Messier M8 Lagoon Nebula shows the difference.


Narrowing only RGB for curves

North America Nebula NGC7000 and Pelican Nebula IC5070

Triggered by Astrometry.net I restacked my pictures of the North America Nebula using DeepSkyStacker. Using CS4 I changed my way of editing the stacked result :

1) slightly sharpen the picture using unsharp mask
2) narrowing each Red, Green and Blue curve
3) narrowing each Red, Green and Blue level

The result is much better then my previous editing and the "head" of the pelican is clearly visible.
The pictures are taken with Nikon D7500 on TALAPO 80/480 f/6. A total of 11 pictures, each 30s with different ISO levels.