Thursday, February 6, 2014

Timelapse from northern Finland (by Henri Luoma)

There has been some time now, that I've not updated this blog. I found recently on the Facebook, a link to stunning night timelapse video from northern Finland (what is really worth of mentioning). The photos and video is made by Henri Luoma. Click here to see the colorful nightscapes.

Saturday, December 14, 2013

Nikon DSLR battery project, some changes

Nikon battery project continues, after a long time "no activity" period. There is going to be  changes in the converter and battery configuration. Because the availability status of MHB75-12S12 -converter from ELFA (expected availability after 03/2014) and and battery capacity (to be increased), the new system will have two 4S LiPo batteries. Second battery in the system will be from Orion, 4S LiPo 14.8V 6400mAh. This doubling the portable battery capacity, what is needed mainly for tracking mount and dew heaters. Converter will be a model of 24V to 12V, Meanwell type MHB75-24S12.

Saturday, July 13, 2013

New halotype observed

Couple of days ago, there was dropped a very nice observation into Taivaanvahti -database. There was a set of images, showing a new previously unidentified type of halo. It was located approx in the middle of upper parts of 22 ring and lower part of CZA. Haloarc is curving slightly upwards. See Marko Mikkilä's observation details here:

The name of halo is not known yet. Also the fact, what kind of crystals this halo would require, is still unsure. According to text, there is already a preliminary simulations done. Still there is no data available publicly. Hopefully we hear more of this, in near future...

Monday, March 18, 2013

Visit to Nuuksio

On the 9th March 2013, there was another trip to Nuuksio. We did photograph some nightsky timelapse - for the startrails image. Totally 36 images were taken, before my Nikon D200 jammed - due to low temperature.

Other activity this night, includes visual observing, with colleagues 25cm newton. For the solar system, we took look at Saturn. Most of other deep sky targets, were from the Messier catalog. The familiar M81/82 pair showed nicely. M101 was a bit more difficult then, it showed as faint large are smudge. I did not see the sprilar construction of this galaxy.

Returned to home, after two...three hours of observing. Thanks to Tomi for the car ride :-)

Sunday, December 9, 2012

Sir Patrick Moore, R.I.P

From BBC news today...

Sunday, November 11, 2012

ISS and Sun (10th Nov 2012)

Another alarm again, from CalSky service. This time ISS would have passed in front of Sun disk at Espoo / Finland, on 10th November 2012. Estimated time was approximately 12:33. I tried to follow, also this time - plans were not successful. Sky was full cloudy...

Monday, November 5, 2012

Nikon DSLR battery project, converter selection

Some background investigation is done now. Few samples from couple of DC/DC converter manufacturers, seems a good solution. One that I first noticed, was 75Watt series from Meanwell. Type MHB75-12S12 provides conversion from 4S LiPo cell voltage to constant output voltage. Most important spec are:

Half-brick size (2.28" 2.4" 0.5")
2:1 wide input range
Protections: Short circuit / Over current / Over voltage / Over temperature
High efficiency up to 89%
Built-in remote ON/OFF control
Built-in remote sense
Trimming output 10%
Five-sided shield metal case

For more detailed information, check MHB75-12S12 specs here. This type of converter, is in sale at Elfa Distrelec.