First timer, focusing (?) problem

Discussions of Electronically Assisted Astronomy using the Live Stacking feature.
psy1280
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First timer, focusing (?) problem

Post by psy1280 » Wed Oct 31, 2018 2:11 pm

My first time using SharpCap last night was...well, disastrous. After experimenting on distant terrestrial objects, I though it would be just as easy to go to the stars. Unfortunately, I was only able to get a black screen. I tried many trial-and-error adjustments to no avail. I suspected it was a focusing issue, tried all of the focusing tools, nothing but red bars. No matter how I tried to focus my Evolution 8 scope, nothing materialized except at one point some amoeba-like greenish blobs (reminiscent of the cosmic background images I've seen). I realize I'm totally out of my element using SharpCap, but I'm determined not to give up. Specifically:

1. Why am I able to see terrestrial objects and not stars has me stumped.
2. Why I wasn't able to use the the focusing tools (I turned the focusing know all the way, back-and-forth, to each extreme (still only red bars on the focus tool, with an occasional, rare yellow)
3. Why my screen remained totally black no matter what I did or tried (I did experiment with everything, Live Stacking, etc.)

If anyone can sympathize with my total chaos I would sincerely appreciate the help in at least seeing something (anything) on my screen. I suspect that I need a SharpCap for Dummies manual, as I did read the entire manual, obviously, it didn't sink in. I won't give up and this post is my first step in trying to evolve with Sharp Cap.

I'm using the Revolution 2 Imager

Thanks to anyone for helping

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admin
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Re: First timer, focusing (?) problem

Post by admin » Wed Oct 31, 2018 7:46 pm

Hi,

the first steps are the hardest in astrophotography, so stick with it and you'll soon get there.

SCT telescopes have a very wide focus range and the distance you have to move to go from terrestrial objects to stars can be further than you think. It's also easy to get lost in that wide range of focus adjustments and be so far out of focus that you see nothing at all.

The focusing tools will only help you when you are already fairly close to focus - they are designed to get you from close to 'best' focus, so you need to forget about those to begin with and focus manually.

Ideally, pick the moon as a target - it's big, bright and easy to find. If that's not possible aim for a nice rich star field with plenty of bright stars and set a high gain and exposure (max gain, exposure 2-4s). When you are way way out of focus you will see nothing from stars and just whiteness from the moon. As you move closer you will start to see big blobs or donut shapes from stars - just keep moving the focuser in the direction that makes them smaller and you will soon get there.

hope this helps,

Robin

psy1280
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Re: First timer, focusing (?) problem

Post by psy1280 » Thu Nov 01, 2018 6:54 pm

Robin,
Thank you so much. I will do as you suggest. Also, I'm using a Windows 7 laptop with Sharpcap 3.2 (is the best configuration/download for my laptop)?

It's a wonderful program and your prompt response to such a nebulous (no pun intended) question is much appreciated :D

Joe

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Re: First timer, focusing (?) problem

Post by admin » Thu Nov 01, 2018 7:50 pm

Hi Joe,

SharpCap 3.2 on Win7 is fine.

cheers,

Robin

psy1280
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Re: First timer, focusing (?) problem

Post by psy1280 » Fri Nov 02, 2018 2:47 pm

Robin,
You said I should set a high gain and exposure (max gain, exposure 2-4s). In my camera settings there are no options for either 'gain' or 'exposure'...am I right to assume that gain is the same as gamma? And that exposure would be the "frame Rate Limit"?

Also, since there are no clear skies I tried a terrestrial target today and had an awful time finding focus...I understand what you said about the difficulty with SCTs focusing, are there any tools or accessories that you know of that can help finding focus when using a SCT with SharpCap?

Thank you for helping me get involved with SharpCap
Joe

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turfpit
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Re: First timer, focusing (?) problem

Post by turfpit » Fri Nov 02, 2018 7:29 pm

Joe

For your type of camera, exposure and gain are in the camera's menu system which is accsessed usually via a hand controller or buttons on the back of the camera. You should find exposure and gain (AGC=Automatic Gain Control) in the menu system - these settings are not exposed in SharpCap. A Quick Start guide and Reference Manual can be found here
https://www.revolutionimager.com/pages/menus-r2. Also see https://docs.sharpcap.co.uk/3.2/#Frame%20Grabbers

The attached is something I wrote for another of these LN300 style CCTV cameras. There are some guidelines for settings - I pulled all the menus and settings together for my own sanity.

Dave
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camera_menu_DSO-1_2015.pdf
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psy1280
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Re: First timer, focusing (?) problem

Post by psy1280 » Mon Nov 05, 2018 2:38 pm

I can't believe how responsive you are to questions. Many, many thanks.

Joe

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Re: First timer, focusing (?) problem

Post by turfpit » Tue Nov 06, 2018 10:37 am

Joe

The attached is a hack from an old document, it might be some help to you?

Dave
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Using a CCTV style Camera.pdf
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psy1280
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Re: Suggestions on how to grow with this hobby

Post by psy1280 » Thu Nov 29, 2018 4:00 pm

After trouble with my WiFi mount and endless cloudy skies I haven't had a chance to experiment with SharpCap. I've downloaded the PDF manuals and have come to realize just how ignorant (I mean Ignorant with a capital "I") I am of all this (being a psychologist, I only know people :D ). Can you suggest any books or reading material that would shed light on all of this? I did view the YouTube video on stacking, which I found to be extremely helpful, etc. If you could suggest any resource where I might begin to develop competence with video astronomy (especially using the features of SharpCap) I would truly appreciate it.

I watched your interview yesterday with AAA Astrophotography, it was inspiring!

One further question, and I know I'm putting the cart before the horse, but since I'm determined to devote myself to this hobby, would I be better off purchasing SharpCap Pro from the start? I have 3.2 now, but I was wondering if the features of Pro would benefit me with my learning curve(s).

What an amazing contribution you've made to amateur astronomy. I'm deeply grateful
Joe

BlackWikkett
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Re: First timer, focusing (?) problem

Post by BlackWikkett » Thu Nov 29, 2018 5:40 pm

Hi Joe,

I'm relatively new at the astronomy game myself. Captured my first image in July 2017. I've been using SharpCap for about a year and I've had my share of problems getting my head around some basic concepts and the software that's being used in the hobby. I've found a very helpful community of astronomy hobbyist at https://www.nightskiesnetwork.com/ Come on over and check it out, usually someone is broadcasting their views nightly. I broadcast myself now and their are several users of SharpCap where you'll see the software in action real time. We have voice comms and chat and we're all happy to answer viewer questions. Hope to see you there!

-Wikkett

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