Jump to content

We politely request that members refrain from discussing politics and/or the Brexit debate on East Midlands Stargazers. Let's keep it to the topic at hand... Clouds. ☁️

  • Join the East Midlands Stargazers astronomy community today!

    Test

Sign in to follow this  
Graham

First serious imaging attempt with the big scope.

Recommended Posts

Graham

After much tweaking with the collimation over the past month or so I finally decided it was time to see what this old girl could achieve.

Although the seeing was not great tonight I loaded up the Canon 1100 D and lined up on M3.

As this camera is new to me I spent a while just playing with different ISO values and exposure times.

I settled on ISO 800 and a 90 second exposure time.

 

After having a few problems with BYE the other day I decided to use Maxim tonight to capture the subs.

The St4 guiding was taken care of in PHD 1.

 

Astro modded Canon 1100 D

51 subs at 90 seconds.

No darks or flats. ( Big mistake 😅 )

 

Stacked in DSS  ( I don't think I used the correct debayering setting as there was not one for the 1100 D, so I took pot luck )

Tweaked in PS 6 

 

Focus is on the soft side and the colour is a bit off but all in all I am quiet pleased with the result.

 

 

spacer.png

Share this post


Link to post
Share on other sites
Bottletopburly

Well it is a start graham im sure once you tame the beast it will pay dividends ,maybe an autofocuser in the mix would help  ,i'm assuming here you need a pair of step ladders to get to the focuser . 

Share this post


Link to post
Share on other sites
Derbyshire Dave

Very acceptable for a first shot with the beast. You must be well pleased Graham

Share this post


Link to post
Share on other sites
Bino-viewer

Impressive image Graham for a 'first light.' Hopefully the first of many more ! 😀

Share this post


Link to post
Share on other sites
Ron Clarke

Good start Graham, Canon debayer is RGGB, can you dither? It will save you taking Darks?

Share this post


Link to post
Share on other sites
Graham

Thanks folks.

I am pretty happy with the result for a first image.

I have been doing a review of this today and have discovered my mistake with the focusing.

 

Not being used to using a DSLR it would seem I did the focusing on a half size image not a full size.

Must remember in future Maxim displays the Canon image at 25% not at 50%as with the Atik.

 

Dave don't do climbing on step ladders in the dark I use an electronic focuser.

 

Ron I can dither so will give it a go next time.

I used the Canon 1000 D debayer mode in DSS.

I will use the basic RGGB mode next time.

Share this post


Link to post
Share on other sites
Bino-viewer

Can someone explain this dithering business to me please ?

I understand the fundamentals of it (i think) but why would it negate the need to take dark frames ?

Share this post


Link to post
Share on other sites
Graham
1 hour ago, Bino-viewer said:

Can someone explain this dithering business to me please ?

I understand the fundamentals of it (i think) but why would it negate the need to take dark frames ?

Dithering moves the dead center of your image by a few pixels each time you take an image in a series.

By doing this the same pixels of your sensor in each image never sit exactly on top of each other when you stack your images.

If you have a hot pixel if you take 20 images in a series the hot pixel will move position each time in relation to your target,

When you stack the images the hot pixel will be covered by 19 good pixels and vanish from the final image.

 

Dark frames show the noise created by the chip in the camera.

Like the hot pixel this noise is moved each time when using dithering.

So will stack out.

 

The only thing it wont cure is amp glow but very few cameras produce bad amp glow any more.

Edited by Graham

Share this post


Link to post
Share on other sites
Bino-viewer

Thankyou for the explanation Graham.

 

So if you were to say...take 30 x 30sec subs, would you have to then manually move the scope a tiny fraction

in between each exposure to achieve this ?

Or would your imaging software do this for you ??

 

 

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.