Sol Ha 17 Dec

[vineyard]

Hello,

Hope all safe & well. Managed to get some images yesterday in the lovely morning sunshine, and have been tinkering a bit w various processing approaches.  JPGs below for size.  Kit was TV76 w a SF-50 etalon (a treat to myself ) with an ASI178MC.  I think I will start researching mono cameras now!

Stay safe all,

Vin

 

[Kitsunegari]

if this is an SF-50 etalon, I think you may need to focus attention to how it is mounted.  It appears that it may not be "Squared" to the objective , (It should be flush mounted)  There is some extreme banding which should not be there.      This brand of etalons are supposed to be completely uniform across the entire field.    

 

 

If you are certain it is mounted properly,   you may want to examine the blocking filter for oxidation and degradation.       The images are great, but there is something up with the tune. of this setup, 

 

It would be in your great interest to investigate this issue, because you have a legit scientific instrument which cost a pretty penny,  It is not functioning as it should be.  (sorry to sound negative, just trying to make sure you get the best bang out of this amazing piece of equipment)

 

[vineyard]

Thanks @Kitsunegari I will try & check.  The mounting ring threads in finger tight, and then I thread the etalon on finger tight.  Could it be just that I need to try different settings on the tuning dial?  This was a demonstrator model that Helmut was using (hence I got a discount) & he did clean and field-test it before shipping.  Usual Solarscope philosophy of returns, fixing etc still holds, so I will look into it (not sure when the Sun comes up now!).

Is there anything in particular I should look for (just an even intensity on a stacked image - is there a way of telling that in live view mode b/c I've noticed that seeing varies so trying to see whether its tuning or just seeing is a learning curve I am still on!).

Cheers.

[vineyard]

7 hours ago, Kitsunegari said:

There is some extreme banding which should not be there.      This brand of etalons are supposed to be completely uniform across the entire field.    

 

 

Here's a different whole disk image from the same session (PNG instead of JPEG).  I had done some sharpening on it (ImPPG & then High Pass in GIMP) and played a bit with levels.  What I can see is that the SE quadrant is slightly brighter, so is that the sign that tuning could have been better (or that something else is happening - hopefully not - w the blocking filter etc)?

 

[Nigella Bryant]

Hi, yes, tuning is off, it should be a uniform illumination of the disk. Edge's usually slightly darker. Re: reference my image albeit from my Lunt 60mn DS. I use a Zwo ASI 178mm. Mono camera and add false colour in PS CS2 ( old, lol ).

Edited December 19, 2020 by Nigella Bryant
More comment added.

[richard ashbee]

would be very happy with these

[vineyard]

Thanks @Nigella Bryantwill try that next time there's some sunshine - tbh, I've just liked what I've been able to see with it so much w the naked eye that I haven't tried the different tuner settings that methodically - will try that next time & report back.

PS - that is an amazing image btw!

Edited December 19, 2020 by vineyard

[Nigella Bryant]

33 minutes ago, vineyard said:

Thanks @Nigella Bryantwill try that next time there's some sunshine - tbh, I've just liked what I've been able to see with it so much w the naked eye that I haven't tried the different tuner settings that methodically - will try that next time & report back.

PS - that is an amazing image btw!

Hi vineyard, solar observation/imaging is completely different than any other form of imaging. Getting the tuning right is paramount for both to get the best out of your set up. I did do a tutorial on how to tune your ha scope a while back here on SGL. It's a learning curve but once mastered it's easy every time. The only caveat is when you have cloud going across the disk which makes it a little more difficult, not impossible, but a little more difficult. Found the title below.

Imaging Technique to attain on band HA and full illumination

Edited December 19, 2020 by Nigella Bryant
Added comment

[vineyard]

25 minutes ago, Nigella Bryant said:

Hi vineyard, solar observation/imaging is completely different than any other form of imaging. Getting the tuning right is paramount for both to get the best out of your set up. I did do a tutorial on how to tune your ha scope a while back here on SGL. It's a learning curve but once mastered it's easy every time. The only caveat is when you have cloud going across the disk which makes it a little more difficult, not impossible, but a little more difficult. Found the title below.

Imaging Technique to attain on band HA and full illumination

Thanks - read that w interest.  Those are good tips to over-expose and then centre the illumination 🙏🏾 I will try those next time (I've just been so happy to see the sun that I've not been patient ).

[Kimboman]

Great topic /comments and photos thanks for shearing them with us

[vineyard]

Hello,

So I tried a couple of different approaches v quickly today.  Attached as JPEGs for size.  Same settings in ImPPG on both, and same High Passes in GIMP.  Nothing else done.  The seeing was better for the 2nd so there are more images stacked.

What are your views on which image has better tuning/illumination?

Thank you & stay safe!

Vin

 

[Nigella Bryant]

6 minutes ago, vineyard said:

Hello,

So I tried a couple of different approaches v quickly today.  Attached as JPEGs for size.  Same settings in ImPPG on both, and same High Passes in GIMP.  Nothing else done.  The seeing was better for the 2nd so there are more images stacked.

What are your views on which image has better tuning/illumination?

Thank you & stay safe!

Vin

 

Definitely the second one. Seems the band width is more in tune and uniform. The orange peel affect over the whole disk is more uniform which also indicates better tuning. The first image you can see the opposite is the case. Also the filaments are more pronounced in the second also indicating better tuning. Well done.

[Kitsunegari]

I agree, the second one in the most recent post is the most uniform.   The issue is not with processing,  it could realistically just be your focuser.   

 

Try using extension tubes and not the actual focus wheel on the scope.    This will sort out any slack in the focuser if there is any, could be that simple.

[vineyard]

6 hours ago, Kitsunegari said:

I agree, the second one in the most recent post is the most uniform.   The issue is not with processing,  it could realistically just be your focuser.   

 

Try using extension tubes and not the actual focus wheel on the scope.    This will sort out any slack in the focuser if there is any, could be that simple.

Thanks.  It is an old scope so that's a possibility - could a tilter help (I keep it for occasional NR but could just set it as part of the standard train)?  Cheers & stay safe

[Nigella Bryant]

26 minutes ago, vineyard said:

Thanks.  It is an old scope so that's a possibility - could a tilter help (I keep it for occasional NR but could just set it as part of the standard train)?  Cheers & stay safe

Hi Vin, I always have my tilt adapter in the train.