Jump to content

sgl_imaging_challenge_2021_2.thumb.jpg.72789c04780d7659f5b63ea05534a956.jpg

Question about EEVA


Recommended Posts

Hello fellow star gazer 

I have a few questions about EEVA. # 1 can I use my 10" standard dob to start out in EEVA,#2 Is it recommended to start out with a cmos  camera ? Any advise is appreciated  !

clear sky's everyone

ken

 

34C305E9-EEA1-4B9C-8AED-6BD710FD4E9A.jpeg

Link to post
Share on other sites

Hi Ken

On the CMOS question you'll (I hope) get various opinions. Personally, I think CCD cameras without user-settable gain/bias are actually easier for beginners (and for experience observers for that matter). However, there is a much greater choice of reasonably-priced CMOS sensors and many EEVA observers seem to have moved to CMOS (though not so much on this forum).

I've been using a small sensor CCD guide camera (the Lodestar X2 mono from Starlight Xpress) for EEVA for nearly 7 years and am very happy with it, even though in theory it lags behind some CMOS offerings in terms of things like read noise. 

A far more important issue than CCD/CMOS though is matching your sensor to whatever scope you end up using. This is going to have a much bigger effect on your experience. Check this out for some pointers: https://astronomy.tools/calculators/ccd_suitability

Happy to discuss more!

Martin

  • Thanks 1
Link to post
Share on other sites

Hi Ken,

Like Martin I use a CCD camera. I use the Ultrastar camera/starlight live software combination and use the Jocular software to produce my "live images". This combination works very well. Take a look through the EEVA forum to view the various posts and get a feel for what set ups folk are using.

Cheers

Mike

Link to post
Share on other sites
  • 1 month later...

I’ll give a shout out to recommend a cmos camera for the simple reason that you’ll get (for most people in most situations) a better performing camera, cheaper. In addition, with low read noise CMOS you can bin with very little penalty (treat multiple pixels as a single pixel to get more sensitivity, at the cost of lower resolution). These days CCD sensors are being manufactured by fewer companies since they are less competitive on price and performance.

When I started I was concerned about having to pay thousands for a camera, however the costs of cmos sensors has dropped rapidly as the quality has risen. You can get really excellent cameras for a few hundred pounds.
 

Martin is right though, make sure you’re matching the sensor size to your scope for the things you want to see. In terms of field of view you can crop in, so a larger sensor is less restrictive than a smaller one. Most important is that you need to make sure you are not under sampling (too little resolution due to the pixel size) the objects you want to see. Do try to match correctly, but oversampling is much less of an issue because the cost is lower sensitivity which you can compensate with exposure and on cmos, binning. 
 

And you will need a driven mount. I have actually done dso  eaa without a driven mount but I was using a camera lens not a telescope, so I had a very fast lens with a wide angle view. The stacking software did its thing as normal for a bit before the image slid off screen. The main advantage was speed of set up. Even then, it was more trouble than it was worth.

The only exception I would suggest is if you are only interested in a live view of planets or similarly bright enough objects where your exposures are under the 0.1s range . Again, even then you’ll be knocking the telescope repeatedly to keep things in view and it’ll be a bit tedious. 

Link to post
Share on other sites

I agree with most that's been said and want to add that CMOS cameras have advantage in lower read noise.

EEVA is about short exposures and stacking them. Read noise is only thing that makes a difference between single 10 minute exposure and stack of 600 one second exposures. Lower your read noise - less difference between the two.

For this reason, CMOS cameras (low read noise ones) tend to perform better for EEVA.

CCDs have advantage of being able to bin without read noise increase.

On the matter of driving the scope - you can probably start with EQ platform. This is going to be a bit more involved way of "observing" as you'll need to locate objects manually by aiming your scope and if you have small sensor - it will sometimes prove difficult to place object on sensor. Goto is much better for this.

If you plan on using small sensor (most affordable option) - look into x0.5 reducer as your scope has quite a bit of focal length - 1200mm.

Here is what can be captured with such scope and small sensor camera (like ASI120 - 1/3" sensor) with x0.5 reducer:

Screenshot_1.png

M82

Screenshot_2.png

M81

Screenshot_4.png

M42

This was from location with substantial light pollution - red zone bordering on white. I don't remember capture details as it was some 5 years ago (but I think I used 4s exposures and stacked few minutes at best).

 

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • 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. By using this site, you agree to our Terms of Use.