SharpCap Forums

Joe,

You wrote:

(instead of the 100 you suggest)

I didn't mean to suggest that you use gain 100 nor am I suggesting that you use 30s exposure. I'm just asking what gain and exposure you used for the Veil Nebula. Whatever it was that you used, I want you to use it again.

Brian

Joe,

Hmm, there used to be a way to delete a post. I guess Robin disabled it.

What you can do instead is:
1. Click the "pencil" icon.
2. Delete the contents of the post, and replace it with "(deleted by author)"

Brian

To be clear, I'm going to the "Start Capture" function, NOT the "capture Darks" function, right?

Joe,

That's right. I believe that the "Capture darks" function will create a single Master Dark file. I need all of the individual files that make up the Master. So, you are right, use "Start Capture" but make sure to set the Target Name to "DARK" so I can differentiate them from the "BIAS" frames.

Brian

Brian,
Just sent you a gmail to explain some problems with my gmail....hopefully I can get the files to you soon.
Joe

Brian,

Okay, the files are being sent to you via Google Drive Link. Please let me know if there's a problem.

Thank you for doing this...

Joe

Tried again tonight to send the folder...thanks for hanging in there with me on this Brian.

Hi Joe,

Excellent work! Every frame looks perfect. I've attached screenshots of the Master Dark and the Master Bias.
There is no need to capture anymore Bias frames. But with respect to Darks, it is up to you if you want to capture a set of 30 Dark frames using a different exposure. I figure that it might be a good idea since the weather is still lousy and the camera is already detached from the telescope.

So far, your Darks and Bias look great. What's left are Flats and Lights. After you finish with Darks, I think you should move onto Flats. In my opinion Flats are the most challenging to capture. Let's see what you get!

Brian

Brian,
Thanks once again for doing all this. I've always suspected it was my flats and/or dark-flat subtraction. I do, however, have a dark library, perhaps it's time to re-do the dark library). As for flats...my work flow is to get a test flat to ascertain the exposure and gain for making a dark-flat, then apply that to making the dark-flat, then I do a flat (using a light panel) with the dark-flat subtraction. prior. I will scrutinize this process going forward.

I'll be focusing (no pun intended) on that my flats next time out.

It's good to know that my camera functions properly (re: bias and darks)

I wish I could repay the favor, would love to stay in touch

Joe

Joe,

As the owner of a CMOS camera, you need to pay particular attention to matching the gain across all calibration files and Lights. Is there a possibility that you used different gains? That certainly could caution problems.

Here is a cheat sheet:

1. IMPORTANT: ensure that the gain is the same for all Darks, Dark Flats, Flats, and Lights.
2. The exposure must be the same for Darks and Lights, for example 30 seconds.
3. The exposure must be the same for Dark Flats and Flats, for example 2 seconds.

I don't recommend capturing Dark Flats until you solve the bigger issues. I never captured Dark Flats until recently, but only when I use the Hydrogen Alpha filter. Dark Flats improved the image but it was barely noticeable. I've heard you say that people recommend Dark Flats, but you have bigger problems to solve first. In my opinion, Dark Flats won't make a huge difference.

Brian