Canon 60Da Noise reduction and Focusing questions.

[Seldom]

Noise Reduction: I've noticed that Long Exposure Noise Reduction may take as long as the exposure at the start of a set of exposures but at the end of the set there may be little or no delay between the end of the exposure and the time the image appears on my computer screen.  Is BYEos cacheing dark frames from the start of the run to use on the end exposures?

 

Focusing: I've been using a Bahtinov mask to focus as well as the numerical display on the Frame and Focus screen.  Since the live view display of the Bahtinov can be marginal at times, I'm wondering if I'd do just as well without it.

[admin]

Noise Reduction: I've noticed that Long Exposure Noise Reduction may take as long as the exposure at the start of a set of exposures but at the end of the set there may be little or no delay between the end of the exposure and the time the image appears on my computer screen.  Is BYEos cacheing dark frames from the start of the run to use on the end exposures?

 

Focusing: I've been using a Bahtinov mask to focus as well as the numerical display on the Frame and Focus screen.  Since the live view display of the Bahtinov can be marginal at times, I'm wondering if I'd do just as well without it.

 

BackyardEOS does -NOT- cache images.  What you see is what the camera delivers for each individual frame.

 

I find the Bahtinov feature to work best with still pictures of a second or two instead of relying on live view alone.

 

Hope this helps,

 

 

[astroman133]

Long-exposure noise reduction is a totally in-camera function.  The conventional wisdom is to turn it off and take separate dark frames.  That way you will maximize your time collection photons.

 

I typically take dark frames indoors in a dark room or closet, with the body cap in place, at temperatures that approximate what I will be shooting at night.  That way I don't spend any time shooting dark frames while I can be imaging a target.  By taking darks at different shooting conditions (ISO, temperature, and duration) and combining them ahead of time, I am able to create a library of master darks and apply the the frame that most closely matches the light frames during image calibration.

 

I would read your camera's manual to find out about how LENR works.  When I experimented with LENR it took a dark frame for every light frame.  So, every 1 minute exposure took 2 minutes because the dark frame had the same duration as its associated light frame.

 

I have read that some of the higher end Canon cameras behave differently, but have no experience there. 

 

I always leave LENR turned off.

[Seldom]

Thanks, guys.  Guess I'll need to ask Canon about LENR on my 60Da.  They don't say anything in either manual that would explain why noise reduction time was reduced or eliminated on the end exposures in a set.   When I was using my Panasonic Lumix G2 for AP, all of the LENR times were identical to the exposure times.

 

Follow up:  I just spoke to Canon Tech Support, and the rep there said that he also had no idea why the noise reduction time was reduced for the later photos.