Venus April 18th IR850

[Space Cowboy]

Seeing was like a jelly by this stage (8.15ut).

Taken with QHY5-iii-585c & Auto Dob 250.

Seems dyadic wavelets in registax are needed to bring out any detail. Limb burnout is the main issue.

 

Edited April 22, 2023 by Space Cowboy

[neil phillips]

yes i thinker bolder sharpening would likely work better. Can see some subtle shading. I am going to try 610nm 685nm and 850nm. See what's going on here. Kon is using 685. And seems to be getting quite some definition. from what I've seen deeper is often better. Maybe its a seeing thing. But worth experimenting none the less. Good capture with the poor seeing

[Kon]

Nice capture and I agree with Neil that you can push the sharpening more. I use the dyad and the top two slide bars. You will get a bright edge rind but you can find a nice balance.

[Kon]

@neil phillipsand @Space Cowboy I understand that the tighter cut off will give other features cleaner but why not use the fuller spectrum of IR? We get more signal and in theory other features. My understanding is that the tighter ones reveal more specific features , which are still present in the broader wavelengths but just make them pop?

[Space Cowboy]

11 hours ago, Kon said:

Nice capture and I agree with Neil that you can push the sharpening more. I use the dyad and the top two slide bars. You will get a bright edge rind but you can find a nice balance.

Thanks Kostas. I used the top 3 sliders until the limb shone like the sun then eased back. Took over 45000 frames and every one was like jelly.

With better seeing and higher elevation it will be interesting to see how much detail pops out.

Wondering about getting a filter wheel as I've got 3 IR filters plus the UV and there's such a small window of time  to use them before Venus is obscured or too low.

[Space Cowboy]

On 22/04/2023 at 15:38, neil phillips said:

yes i thinker bolder sharpening would likely work better. Can see some subtle shading. I am going to try 610nm 685nm and 850nm. See what's going on here. Kon is using 685. And seems to be getting quite some definition. from what I've seen deeper is often better. Maybe its a seeing thing. But worth experimenting none the less. Good capture with the poor seeing

Thanks Neil. I'll let you answer Kon's question 🙂

[Pete Presland]

Good looking disc there, a filter wheel is very useful when imaging Venus. Saves a lot of messing around when switching from UV to IR filters. 

I have tried the dyadic setting before on Jupiter, but always found the end result a little "blotchy" (not sure that is the correct description)

Could be interesting to try it on my data from the 17th which i thought was quite good.

[Space Cowboy]

10 hours ago, Pete Presland said:

Good looking disc there, a filter wheel is very useful when imaging Venus. Saves a lot of messing around when switching from UV to IR filters. 

I have tried the dyadic setting before on Jupiter, but always found the end result a little "blotchy" (not sure that is the correct description)

Could be interesting to try it on my data from the 17th which i thought was quite good.

Thanks Pete! On any other planet dyadic would make a mess for sure but it seems to work on Venus. Since I started imaging over 10 years ago this is the first time I've given Venus any serious attention and it's been a steep learning curve.

[Pete Presland]

Always worth trying different techniques on objects to see how the data responds. hopefully some clear skies soon so i can get some I/R data to experiment on.