Peaking through the soup

As a regular reader of my irregular blog, you might have noticed that I got myself a Dwarf-II some time ago.

Just lately, I spent some more time with the device, shame on me. 

You may know that I do live in the Netherlands, one of the worlds most light-polluted regions. On top of that, we have pretty murky skies in general. Not the best for astro-stuff.

Having earned my astronomy degree in the field of open stellar clusters, stellar matter was always interesting to me. Most astrophotographers are focused on colorful images of nebulae, which I do appreciate myself too.

Colorful, i.e. full spectrum images, require a pretty clear sky. Again, no such thing in NL. 

Some weeks ago, I ordered 800nm IR pass-band filters. Those arrived lately. Certainly those are not really narrow-band, but that's OK. 

The main idea was to use the filter(s) in front of the Dwarf-II's telescopic lens. 
The Dwarf-II has an option to pass IR to the sensor. This has got some implications:

First of all, IR light can reach the sensor (daaahhhh!). Not so fast, all other smart-telescopes do not let IR trickle their sensor.

Secondly, this enables an almost monochromatic imaging mode when used with an IR band-pass filter. Well, that is exactly what I described above.

Thirdly, IR astronomy still works in murky conditions, somehow at least.

A minor forth point might be that the RGB-filters on the image sensor might not have a great effect on IR radiation, thereby keeping up the resolution of the sensor.

Why am I so enthused about monochromatic imaging? When taking images of full-spectrum radiation sources, such as star and galaxies, one does not need any other "colors". The particular advantage is that all light from a source will be focused at the same place on the sensor, i.e. not chromatic aberration issues. 

The added benefit of IR is of course the reduced influence of the atmosphere. 

However, when collecting images one needs to understand that the portion of light collected is restricted. Therefore, one might consider to experiment with amplification. 

The following images are screen-captures from my table during acquisition. There is no post-processing involved at all. You also see a photo of the sky conditions during the data acquisition.

stack with statistics

spectrogram and curve

conditions during data acquisition

DWARFLAB app on the Amazon fire HD 8 (2022)

The DWARF II Smart Telescope is a very neat device, embraced by many. I use mine usually with a 10" Android tablet, when at home. This tablet is a little bit too large to fit into the DWARF's bag however.
For portable use of the telescope, therefore my Android phone was the only option. As well as the app is, it is tricky for me to operate with cold fingers. Even with warm hands, the small screen on the phone is not really helpful.
Consequently, I felt the need to purchase an inexpensive Android tablet, small enough to fit in said bag, but big enough for easy operations.

Tablets with smaller screens were popular once. Today, there are only a handful models with modern specs available. The 3 brands I am aware of are Amazon, Lenovo and Samsung. This order seems not only alphabetical, it also reflects prices from low to high. 

Here is an overview about the dimensions in mm we have to consider:
device        length  width
DWARF II      204.0   130.0 (height)
A. fire 7     192.0   115.0
A. fire HD 8  201.9   137.34
L. Tab M7     176.3   102.9
L. Tab M8     198.2   122.6
S. GalTab.A8" 206.6   126.7

All things considered, the Amazon fire HD 8 made the race. First of all, the specs of the fire HD 8 are a lot better than those of the fire 7. Further, the fire HD 8 was on clearance sale, decently reduced, so the purchase of another gadget could be justified.

Does it fit in the bag? Perfectly. 

The big question of course is, if the DWARFLAB app can be installed on a device which is, unless hacked, very restricted in its abilities. Of course the DWARFLAB app is not in the Amazon Appstore, not a big surprise here.
However, DWARFLAB has the app as apk-file for download from their webpage. The "Silk Browser" (the browser of Amazon's fire tablets) surprisingly let me download said apk-file. There was a little trick however: one has to hold down on the download-link until the browser offer to download the link. Just tabbing the link did not do anything for me.

The browser than will ask for permission to write file to storage, with the warning that such files could harm your device.

Once the file is on your device, you can install the DWARFLAB app, after confirming security concerns of  Fire OS.
The application runs perfectly fine on the Amazon fire HD 8.

Having a comfortable UI for the DWARF II, I would consider today's exercise a success.

Godox Lux Senior

Well, that might be a first to me, I am actually praising a product. And no, I was not gifted the product. In fact, I had a hard time to purchase it in the first place. All the usual places were out of stock. Actually, one provider reimbursed my prepayment. Finally I was able to procure the device, surprisingly at a very decent discount. 
That made me think that this product fell out of grace somehow.

So, what are we talking about? It is a flash unit, not a speed light. An old style flash unit that you would traditionally feed flash bulbs to, one at the time.... However, there is a modern interpretation of such a device: http://godox.com/product-a/Lux-Senior.html 

When deployed, the circular reflector has a diameter of 11.5cm. In this setting, the flash creates a directed beam of relatively soft light. Not exactly a beauty dish, but not far from it. That's what you see from the interwebs anyway.
However, there is another non-bespoke way of using the flash, namely with the reflector NOT being deployed. Now we are looking at a 180 degrees light source having a tiny portion of a top reflector towards the subject.  Depending on the settings of your reflectors, this opens a ton of opportunities. Not to mention slaves in this scenario.

Using this unit as a slave opens more options that I am willing to describe. 
I hope that Godox will continue this product! This may be the most flexible one ever, in combinations with remote triggers and light modifiers.

Godox, if you read, continue this path (and send me products for testing).