Focusing.

[melvin]

Hello, may I first of all thank everyone for their understanding and patience with me, you must think I'm not just stupid but very stupid. Anyway I have downloaded the Premium Edition and have sat through nearly 3 hours of the YouTube tutorial as well as downloading and reading the 2.0 manual,there does not seem to be any other version! Anyway I have connected my Canon 600d to my laptop, not on a telescope, and have been trying to focus using BYE but nothing happens. I have tried in all of the modes, Planetary, Focus and Frame Etc. but nothing I do works. I have tried both settings on the lens (AF-MF) but still nothing. Anyone help please.

[astroman133]

Melvin,

 

First, in order for BYE to adjust your lens, it has to be a Canon EF lens, or functional equivalent.  This means that the untethered camera must be able to autofocus the lens when you press the shutter halfway down.  Of course this also requires the the lens be set in autofocus (AF) mode.

 

Then in BYE you must be connected to your camera and on the Frame & Focus screen.  The lens focus controls are only on the Frame & Focus screen.

 

Note that the focus ring, at least on my lens, has only about 30 degrees of travel. If it is rotated fully in one direction then the arrow keys for that direction will appear to have no effect.

 

The picture below shows the Frame & Focus button active, and the lens focus adjustment buttons.

 

I hope this helps.

 

[s3igell]

Anyway I have downloaded the Premium Edition and have sat through nearly 3 hours of the YouTube tutorial as well as downloading and reading the 2.0 manual,there does not seem to be any other version! 

The "v3.1 Manual" is installed as part of the basic BYE Installation, and accessed by simply pressing the "?" icon in the Upper Right Window Frame of the BYE App.  It is also available by Double-Clicking the "BackyardEOS User Guide.CHM" file in the BackyardEOSv3.1 directory (if you have the appropriate Windows CHM App installed).

[melvin]

Hi thanks for your replies, for me this is a steep learning curve but I am determined to master it. I have been getting used to the software for most of Sunday 13th Sept and most of Monday morning. What I cannot understand is the numbers on the right hand side of the screen, I know one is supposed to get them as low as possible to achieve good focus, but I cannot get them to move so I am getting focus using the magnify screen, again on the right hand side or the screen. What do I do? Also when I take a shot of a chimney stack all I get is an overexposed pic which is just a white box. I have referred to my Astrophotography books for the basic settings but still can't get anywhere. I need to understand the settings, both on the camera and software, for both daytime and nighttime. Any suggestions other than take up dominoes!

[astroman133]

Melvin,

 

When you say "the numbers on the right hand side of the screen" I am assuming that you mean the FWHM focus metric.

 

FWHM (full width at half maximum) is a measure of the width of a star, in pixels. You can google FWHM for a more technical explanation. As such it will not be useful for focusing on daytime terrestrial scenes. However, for astrophotography, when you have a bright star inside the zoom box, BYE calculates the FWHM of that star, and updates the value in real time.  Watching that value as you adjust the focus of the telescope you will see the value change.  The goal is to get that value to the smallest number that you can. Also understand that the "smallest number" is not an absolute value.  It is relative to the star that you are using to focus and the sky conditions when you are focusing. This means that the number will be different from session to session.

 

Now, if your picture is "all white" it is because the shutter was open too long. When shooting daytime scenes,  the shutter needs to be very short, perhaps shorter than 1/500th of a second. What exposure and ISO are you using? If you have the "Maximum Sensitivity" setting selected, then that will be something like 2 seconds at ISO 12800.  That may be a good choice for a star at night, but not for a chimney during the day.

 

If you have read the user guide and still have questions about how to use a particular feature of BYE then post that question.  It is very difficult to answer a question like "I don't understand the settings.  What do I do?"

 

Also, the more you understand about how your camera works, the more you will understand what the settings in BYE do.  Have you considered taking a beginner's course in digital photography?  Such a course would help teach you about the settings on your camera.

 

I hope this helps.

[melvin]

Thanks Rick, yes I have considered a beginners course in photography and hope to sign up for one in the next few days. My setting was on 'bulb' which I guess is wrong for daylight. I am just familiarising myself with Byeos, maybe if the skies are good for me, I should try some nighttime pics. I have an awful lot to learn but knowing there are folk like you to help makes it in some way easier. Thanks again.

[s3igell]

If you are attempting to learn Focusing during Daytime, you will need to significantly reduce your Exposure (as Rick says).

 

You will also need to use Visual approximations to get your Focus "As good as possible" before starting to rely on any of the Focus Metrics such as FWHM or HFD.  As well, both of these metrics work by reporting the measurements around Bright Points of Light (Stars or their replicas - a shiny sparkle of Chrome across the road or an Insulator on a Power Line) in your otherwise darker scene.

[astroman133]

Melvin,

 

Bulb doesn't tell you what the shutter speed is.  From the camera's perspective it only says that the shutter will be controlled extermally.  That could be by using a remote shutter, an interval timer or a PC.  In BYE, the Duration dropdown list specifies the exposure duration when in BULB mode.  Typically BULB is one of many possible settings in the Shutter dropdown list.  The other settings, except for AV and Program, are shutter speeds that are controlled by the camera. The shutter speeds range from 30 seconds at the longest down to some very small value that may vary by camera model. 

 

With the BULB setting in BYE, you can choose a duration value from 1 second to some very large value.  This means that there are two different settings for taking, say, a 15 second exposure.  One is to pick 15" from the Shutter dropdown. The other is to pick BULB from the Shutter dropdown and select 15 for the duration.  Which is better, you ask? The answer is that when you pick 15" from the dropdown, the actual duration is controlled by the camera.  When you pick BULB with a duration of 15, the duration is controlled by BYE on the PC.  This makes the actual duration subject to the task scheduling and task switching of Windows, which could cause the actual duration to vary depending on how busy the PC is when it comes time to close the shutter.  For this reason it is better to let the camera control the shutter for exposures of 30 seconds or less and only use BULB for durations of longer than 30 seconds.