Sunspot counting with 76/300 mm reflector

Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 04/26/2021 - 21:29

Greetings,

I am thinking of buying a 76/300 mm reflector (mini-dobsonian) as a grab and go telescope when I need to move abroad so that I wont stop sunspot counting. I am writing to ask if any of you has tried sunspot counting with a telescope with this focal length and diameter. In order to see the entire solar disk,you need a 4mm eyepiece which gives you 75x magnification which I think is a very high magnification easily affected by (bad) seeing. Anyone thoughts/experience on this?

 

Best regards,

George.

reflector

Hi George,

The magnification does sound high. I think all you say is true. Please remember to NOT change your header information as that will make your k - factor return to zero, and it will take another 100 observations with that scope before you'll get a new k - factor.  Just keep in mind you may be over-counting with the larger scope.  

Rodney

 

Affiliation
American Association of Variable Star Observers (AAVSO)
K-factor

Greetings Rodney,

 

Thank you very much for your reply! I am thinking of buying this little dob. Better to submit fewer spots than not making any observations for many months. Also,thank you very much for your advice on k-factor but I have a question on that. I am moving entirely to Linux OS. Till now I was submitting my observations with Sunentry on Windows. I think I will not have any problem with k-factor if I begin submitting my observations with Sunentry but from Linux OS right as long as my personal info and telescope are still the same right?

Lunix

Hi George,

I have not run SunEntry on Linux, please let us know how it all goes with the Java install and SunEntry. If you're having problems let Sara Beck know. Sara @ aavso

There should be no Header changes that need to be made for running SunEntry on Linux.  

Rodney

 

 

Affiliation
American Association of Variable Star Observers (AAVSO)
Running SunEntry on Linux

Hello George,

Like Rodney said, I do not think there is a problem running SunEntry on the Linux OS.

Remember that SunEntry is a Java Web Start application. As long as you have installed Java on your new computer, you should be able to run it.

Perhaps you will find this forum post useful: https://www.aavso.org/cannot-launch-vstar-fedora-linux-v32. It refers to VStar which is also a Java Web Start app so it should be similar.

Let us know if you have trouble.

Best wishes,
Sara

Affiliation
American Association of Variable Star Observers (AAVSO)
SunEntry on Linux

Greetings Rodney and Sara,

 

Thank you very much for your reply. I successfully installed SunEntry on Ubuntu 20.04 LTS. The only strange thing is that when I enter my correct username and password in SunEntry login ,it wont let me in. But when I enter incorrect information it gives me a "invalid username or password" warning. Maybe is there a problem with the communication between SunEntry and AAVSO website?

Affiliation
American Association of Variable Star Observers (AAVSO)
SunEntry on Linux

Hello George,

That sounds strange. I just tested SunEntry and I was able to log in with my correct username and password just now.

As a test, are you able to log in to the AAVSO website? That has the same credentials as SunEntry so if something happened to your password for example, it would fail in both places.

The fact that the login window appeared at all in SunEntry would indicate that it is installed correctly.

I'm not sure what else to check.

Best wishes,
Sara

Affiliation
American Association of Variable Star Observers (AAVSO)
SunEntry on Linux

I ran the SunEntry file through terminal to see the outcome. I think it is a problem related to AAVSOtools but I am not sure. I uploaded the photo and made it a url: https://ibb.co/HHxXZCw . I will reinstall everything to see if this solves the problem.

Affiliation
American Association of Variable Star Observers (AAVSO)
SunEntry on Linux

Greetings again,

I solved the problem by downloading SunEntry.zip file instead of running the .jnlp file with Java Web Start application. Seems that Java and Mozilla do not get along together after the latest Mozilla update. I unzipped the file and run SunEntry through SunEntry.jar (not need to unzip that as well). I also updated my header and submitted a couple of observations. Can you please verify that everything is fine? (Observer's Code: LGEC). Thank you very much for your time!!

 

Best regards,

George.

Affiliation
American Association of Variable Star Observers (AAVSO)
SunEntry on Linux

Hello George,

I see that two observations were submitted by you today. They were for observations made by you on April 13 and April 25 and they look good.

Congratulations on finding the solution!

Many thanks,
Sara