Dwarf II Astrophotography filter head to head comparison: SVBONY vs DWARF UHC, CLS, No Filter

Last night I imaged the Leo Triplet using 3 different filters (and a no-filter control shot) using my Dwarf II (Dwarf 2) telescope’s built in stacking algorithm. Each session had 80 images, 10 seconds exposure, 80 gain, with IR pass enabled. The only difference was the time of night (about 15 minutes between shots) and the filter.  I’m in a Bortle 7 light pollution situation.

The Leo Triplet (a.k.a. the M66 Group) consists of NGC 3628 (to the top of the image, which is North), and M65 (bottom right) and M66 (bottom left)

This is what the DWARF II achieves on it’s own (without any post processing) with no filter:Dwarf 2 shot of the Leo Triplet without a filter

And this is using the DWARF UHC (Ultra High Contrast) filter:
Shot of the Leo Triplet using the DWARF UHC filter.
(Not all that different really…..but the background is a bit less noisy)

Here is using the SVBONY UHC filter:
Leo Triplet shot with the SVBONY UHC filter
(The stars appear to be slightly smaller, but so are the triplet galaxies, and the background noise is reduced).

And since I had the SVBONY CLS (City Light Suppression) filter, I also tested it out:
Leo Triplet shot with the SVBONY CLS filter

My takeaway from the four images above (which look very similar, with only subtle differences) is that the SVBONY UHC and the DWARF UHC appear to have relatively similar performance. Also, the Dwarf II’s built in stacking software doesn’t do a super great job illustrating any difference between these filters.

Perhaps my target is the problem, in that UHC/CLS filters may not help much when imaging galaxies. The next time I get clear skys I will try to repeat the test using a nebula.

If you want to try your own post processing, I’ve posted the Raw Data zip file here.

How to limit charging to 80% on a later model year (2014+) Nissan Leaf

Early (2011-2013) United States Nissan Leaf’s had a “limit charging to 80%” feature in the dash.  Nissan removed this feature from US cars after the EPA ruled that if the feature remained, they had to report a lower battery range because on average the car would not be fully charged when it left. [This ruling was incorrect in my opinion…but Nissan removed the feature so that they could advertise the EPA range based upon a 100% charge of the battery.]

I, and many other people, still like to limit charging to only 80% of the battery total capacity in an effort to extend the life of our EV batteries. [This extra effort may or may not be worth the trouble, and many people advise to just charge to 100% and not worry about your battery health, especially for 2016+ vehicles which have a longer battery warranty. But I like to limit charging of Lithium Ion batteries to 80% if I don’t need the extra range.]

If you wanted to only charge your Nissan Leaf to 80% (unless you need extra range for longer trips) on a regular basis, how can you do it on later model year vehicles?

There are three options that I know of:

1. The only way to get a similar effect (keeping the car below 80% SOC most of the time) using only  inbuilt features (i.e. without spending extra money) is to set up the charging timer to charge your vehicle right before you leave. This only works well if you have a regular departure time each day (e.g. for a static work schedule). Then, when you plug in the car, it will not charge until a few hours before your scheduled departure time, aiming to reach 100% about 30 minutes before you depart. This means that the time the battery sits at 100% is minimized. [If you are clever, you can lie about your departure time so that it is reaching 80% about the time you actually leave…]

The downside is that your vehicle is not “ready to go” if you need to leave for an unplanned trip before your regularly schedule departure time, and if you want to charge any other time you have to remember to disable the charging timer so that it will actually charge when you plug in. [My 2015 leaf has an easy to use button for disabling the charge timer…]
Nissan Leaf charging timer disable / off button

So this can be made to work if you have a regular schedule, but it can also be annoying.

2. You can “mimic” the “charge only to 80%” feature by using a Smart / connected EVSE that has a charge limiter built in. For example, I have a JuiceBox, and when I plug in my 2015 leaf, I use the phone app to set the “plugged in percentage” and “stop percentage” (which I just leave at 80%) and it estimates the amount of power needed and will shut off charging after that amount is used. This requires that you pay money for a smart EVSE…but if you haven’t already purchased an EVSE, getting a “smart” or “connected” one with a similar feature will probably only add 1-2 hundred dollars to the purchase price.

Juice Box Pro 40 front faceplate, original silver model from e-motor-works

3. There is also a 3rd party add-on box you can install in your vehicle called Open Vehicle Monitoring System (hardware device) that would allow you to set a charge % limit and also do things like pre-heat in the winter remotely, and has a lot of other logging features…. but it costs $260 (and if you want to be able to use it on a cellular network away from your home/work WiFi networks or the bluetooth range of your phone, you need to include a SIM card with data capabilities which will also probably have a monthly fee)

Open Vehicle Management System Screenshots

Because I already had a JuiceBox, I use method 2…but if I already had a non-smart EVSE, I would probably go with the OVMS route, as it adds other features to the car.
[Especially since the Nissan Connect system in my 2015 leaf no longer works as it used an older 2G cellular service that has since been retired.]  If you have a brand new Nissan Leaf, it probably includes the Nissan Connect service, at least for the first three year of car ownership.

Post Ubuntu 22.04 upgrade fixes

After upgrading from Ubuntu 21.10 to 22.04 on my Lenovo X1 Gen 5, I had the following issues:

1. The built in video player (Totem) would display H.264 AVC videos squished to the far
left of the video window and only black and white. This appears to be a problem with vaapi, as the following command fixed it:

sudo apt remove gstreamer1.0-vaapi

2. Desktop icons disappeared. Had to manually run:

sudo apt install gnome-shell-extension-desktop-icons-ng

3. Firefox (snap) refused to display a file dialog for uploading files to websites (or download any files) until I manually installed:

sudo apt install xdg-desktop-portal-gtk

3. OpenShot video editor 2.6.1 refused to run. This is more of an issue of 2.6.1 not being compatable with the latest desktop that Ubuntu is using, but to fix it is annoying, as OpenShot has not had an official release since 2.6.1 in Sep 2021. You have to use the “Dailies” appImage (or install from the most up to date source yourself) to get a working OpenShot.

 

4. When trying to open a file on the desktop using the “find software” dialog, I got an error message “Failed to start GNOME software”, which was solved by:

sudo apt install gnome-software

5. Thumbnails would not show up for video files in the file browser, until I installed:

sudo apt install ffmpegthumbnailer

 

May 2022 energy rates – Duke Energy – Orlando Florida

Residential Service rates for Duke Energy (Florida):

$12.45 per month Customer Charge *

13.082 cents per kWh (first 1000 kWh)
15.039 cents per kWh (all kWh above 1000)

* – Duke also imposes a 30$ minimum bill adjustment, so if you use less than 134 kWh of power ($17.55 of electricity usage + 12.45 customer connection charge = $30) they will add a Minimum Bill Adjustment so that your total charges are $30 (+3.37 of taxes in Orange County Florida) for a total minimum bill of $33.37

 

Battery Tray / Door discoloration on First Alert Smoke Detector (2018, SA511)

When changing smoke detector batteries on my First Alert SA511 smoke detectors, I noticed that ONE (of the six) has a discolored battery tray/door. It appears that the plastic used to make the battery tray was of a different composition from the rest of the shell, as it has turned yellow with age, while the rest of the smoke detector has not. (Also, my other five smoke detectors all have pure white battery trays that match the body as well…) Continue reading

It’s March 2022, how is Orange County (FL) doing with Covid-19?


The number of confirmed COVID-19 cases in Orange County last week was 2,018, as low as in mid-December of 2021. The Omicron surge is mostly over, and the new case positivity rate has dropped to 6.9% (close to the < 5% threshold that indicates community spread is under control).

While the total number of cases in the Omicron surge was significantly higher than in the Delta surge, the number of hospitalizations (orange line) was slightly lower, and the number of deaths (blue area) is significantly lower. This is partially due to a larger percentage of the population being vaccinated, partially due to the nature of Omicron (infecting the upper respiratory tract more than the lungs), and partially due to survivor bias from prior waves.

According to the CDC, a total of  3,089 covid-19 related deaths have occurred in orange county , or 212 deaths per 100,000 residents.  The total number of confirmed cases is at 371,647, with more than 1 in 4 residents having been infected over the course of the pandemic.

I am hopeful that by next week the test positivity rate will fall below 5%. The CDC community status tracker just recently changed from orange to yellow:

Gluing the glass lid back on my Glowforge

Remember back when the handle fell off my glowforge? Or when the glass lid detached from the hinge?  After the laser tube went out, I got a (refurbished) replacement unit, which has been working fine for a year. However, now the glass lid on my new (to me) replacement unit started to detach from the left rear hinge.
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Generic WiFi Adapter (SDHC) using the WIFI@SDCF app [Dxingtek/Keytech]

I purchased this (very) generic “WiFi adapter”. (Model AD_wifi_SD) It accepts a Micro SD card, and when powered by a host, generates a wifi network (Default SSID: WiFi@SD, default password: 99999999 [eight nines] ).  I was hopeful that it would expose a webserver that I could access from my linux desktop to download files from the camera’s SD card, but no such luck.

The server resides at 192.168.100.1, and assigns IP addresses starting at 192.168.100.100, however it uses a proprietary (UDP packet) protocol that only works with the provided android or iOS app (Called WiFi@SDCF on the Google Play Store com.keytech.wifisd).

Although it may be technically possible to run this app in an emulated android environment on Linux, I didn’t want to put in that much effort. Especially as it appears that the android app (and likely the SD card server) are buggy, and the protocol does not support error detection or correction.  See the class project paper here in the wifi-sdcf repo by David Buchanan for more details.

In short, unless you only want to transfer files to a phone/tablet and are willing to run the provided app (which is of questionable quality) on your device, probably steer clear of this device. [For Sale: One at the cost of shipping….comment if interested.]

How to paint Mouths, Maws, and Teeth

HOWTO Quickly Paint Mouths, Maws, & Teeth

Here is the quick technique I’ve developed for painting mouths and teeth at the tabletop miniature level of detail. First, mouths are very pink. I like this “baby pink” color, but you can pick any shade of pink that looks good to you. Paint the entire inside of the mouth, possibly even getting a small line around the outside depending upon the type of monster or mouth you are painting. I sometimes do this BEFORE laying down the base color of the rest of the face or body, as mouth interiors are usually one of the deepest parts of the model.

Then, water down some bright red paint (I like this “cherry cobbler” color)
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