Diary of a nature photographer
Study, monitoring, research and photography about the Nature

M51, Whirpool galaxy

This galaxy has been the very first try to take a decent astrophoto, because I had to try twice. In the first try there was the full Moon, and knowing that is not a good idea taking astrophoto when there's so much light, combined with city-lights (light pollution), I wanted to try in any way.

In fact the first try has been a complete failure:

As you can see there's a dark area above the galaxy, due to a moonlight reflection on the coma-corrector of my telescope. 

So I only needed to wait the right moment, I mean without the Moon. And so it was!

These ones are the work of two nights, where I take 40 lights frames, 20 dark frames and 60 flat frames, for a total of 2 hours of lights integration:

 

For comparison, I put both the black-white version and the colour version, got in two different elaboration sessions.

For both, I've used PixInsight, but for the colour version, I had to study how to achieve some result, like removing vignetting, colour gradient and clean the noise present everywhere.

For pilot my setup I've used the ASI Air, where I got an excellent result:

The graph-guide was really close to the central line, sign that the mount was working very well, apart from some moments when there was the wind.
Speaking about frames, for this picture I've taken 40 light frames, 20 dark frames and 60 flat frames, but no bias frames because using a CCD camera it doesn't need to take bias frame. I've tried to take them, but PixInsight couldn't extract any information, so it was unuseful.

Finally, it's been a good experience. I've learnt a lot of things, what to do and what to not do, but if I want to keep on taking pictures in town, I need a filter for the light pollution.

See you.

Recently I've worked to improve my astrophotography equipment. Basically, I've made a powerbox for the mount and for two dew-heaters, but for a flat-box as well. The process it's been quite short, and I got my powerbox using a plastic tool-box and three lithium-batteries. So, after many works, you only expect to use them and you wait for the right night, a night without moon or at least a small moon-phase, in order to not have too much light pollution (I know, I'm living in a town, so it's really hard not having light pollution!!!!). Anyway, when you think the night is right, you soon discover another problem.... wind!!! Arrgh! After many cloudy nights, having even only one clear night is gold, but with the wind is always a big deal for astrophotography. But, as always, there's a solution.

A windshield!!!

Obviously, someone would tell, but wich windshield??? A tent? A solid wall? And what if I like to move it? The solution isn't so simple, but I think it might be practicable using Polionda sheets merged together to form a barrier for the wind. Polionda is really light and easy-portable so it should be very easy to use it every time I need it. For now, I've just made a small project on paper, but soon I'll buy all I need to make it, so stay tuned, I'll get back really soon.

Bye

 

#26/04/2020 Update

That solution wasn't good enough. Unfortunately, Polionda isn't stable as I hoped, so with a medium wind it shakes a lot, and it's quite impossible to use it and protect the telescope from the wind. Even though with long laces, for blocking it somewhere, it isn't so useful, so I have to give up with this idea, a stupid idea.

On the Net, I've seen some portable tent. They are not so expensive, but I think it takes a bit time for mounting, and every time I want using the telescope I'd have to mount the tent, the telescope and so on. A bit of work for some pictures, maybe too work, and I don't know if it worths.

For now, I'll give up and I'll use my telescope in no-windy days, hoping to have no Moon as well!!!

See you.

IC434

IC434 also known as Horse nebulae, is really hard to take, mostly inside a town where the light pollution cut much light coming from stars, galaxies and, of course, nebulas. I should buy a light-filter-pollution to prevent this problem, but it's quite expensive, so I'll wait until I'll have enough money.

In this last work, I should have learned some important things. First of all, don't change the ASI Air guide parameters so strongly. Using these settings:

 

I got this guide-graph:

 

that is pretty good for that night, where sometimes it was slightly windy and with a Bortle scale of 8. After a couple of hours of work, getting a lot of cold, I caught this image:

that is the sum of 49 light frames, 10 bias frames and 9 dark frames. For the image stacking and elaboration, I've used Pixinsight, in a trial version for now, but I hope to buy it really soon, making the last final retouch with Adobe Photoshop. I know that the final image isn't so good. I know there's some problem with the stars in the left up and right low corners, but I can't figure out why. Then there's always the moisture problem that I hope to solve with my home-made dew heating band, that I'll try it next time.

As always write to me if you want for some advice or anything.

Bye

Finally after a long time I put the telescope back to work.
The problems I had complained about in the past relating to driving were certainly due to the incorrect configuration of the ASI Air following a firmware update. Yesterday after another update I checked everything again, reset the parameter on the tracking and started the session without any other problems. I quietly made 120 second exposures in which everything remained stable.
But, as often happens, there was a hitch.
HUMIDITY !!!!!
Damn dampness that clouded the correcting plate of the telescope and the lenses of the guide-scope and the finder.
Yes, of course, it's also my fault that I didn't put the protection on (I made one myself, but it works more or less), but I didn't think it would also mist up inside the plate.
Moral ... I had to stop shooting the light-frames and turn everything off.
I think the best solution is a nice anti-condensation band, those that work on 12V and I don't think about it anymore. But now that I think about it I will also need a power supply for the band, which is not the classic lead-acid battery because it doesn't last me much.

Newsflash:
I've updated the gallery adding some new species, like the Asio otus ... Read More
A short Review of the Photoseiki TB-101 gimbal head ... Read More

Haliaeetus albicilla

Haliaeetus albicilla
Haliaeetus albicilla
A couple of white-tailed sea eagles. Lofoten, Norway. July 2018