Exposure Bracketing

[Guest Jack]

What is the recommended/preferred method to setup exposure bracketing in BYE?  I plan to use the program during the upcoming solar eclipse and would like to automate some bracketed shots.  Do I just setup a capture plan listing each desired exposure?  If so, how many entries will the plan accept?

Thanks.

[astroman133]

Jack,

In a recent version of BYE, the number of rows in a capture plan was increased to 100, for the Premium version only. The limit for the Classic version is still 25 rows.

BYE does not work with the camera to do exposure bracketing. By that I mean that there is currently no way in BYE to change the camera's exposure bracketing setting and there is no way to read the setting and take 3 bracketed exposures for each configured exposure. That said, if you configure exposure bracketing in the camera, and then configure each row of the capture plan to shoot 3 exposures, then those 3 exposures may be bracketed. I have never tried that, but it may be worth some experimentation.

What will be difficult will be to stop capturing at the point where you want to change bracketing. For example, after 1st contact until just before 2nd contact (and just before 3rd contact to after 4th contact), you will be imaging the sun as though it were completely uneclipsed. This means that you can set up your imaging gear now and determine the best exposure to use. I have already determined that I need to use 1/1000th of a second at ISO 100 for my camera, telescope, and filter. No bracketing should be necessary. Then, once the filter comes off to shoot Bailey's Beads, the Diamond Ring, and through totality, things are pretty hectic. There may not be time to enable exposure bracketing in the camera without sacrificing some of those important images.

I would suggest reading Jerry Lodriguss's tutorial on how to image an eclipse before deciding on whether to proceed with the use of exposure bracketing. 

[jforkner]

Thanks for the reply astroman133.  I tried your suggestion, and it worked!

I setup the camera for auto exposure bracketing (AEB)—the Canon 6D allows for one image either side of standard exposure, one decreased; one increased.  I left the drive mode set to single exposure.

I then created a 3-line capture plan.  Each line was set for 3 exposures & ISO 100, with a unique aperture & duration.  For my test, I used:

LINE 1:    3 exposures    2.0 sec.    f/5.0        ISO 100
LINE 2:    3 exposures    6.0 sec.    f/11.0      ISO 100
LINE 3:    3 exposures    13.0 sec.   f/16.0     ISO 100

Then I hit Start Capture.  The result was 9 images—3 sets, each with one image as programmed & one exposed either side.  For example, the first set was exposed at f/5.0, ISO 100, & 2.0, 0.6, & 6.0 sec.  The other sets were similar.

So clearly BYE is capable of performing exposure bracketing within the camera’s limitations.  But as you point out, making changes may be a problem.  Not sure I’m willing to commit to a predetermined set of exposure settings based on a previous eclipse.

Thanks again for the great suggestion.

Jack

 

[Lord Beowulf]

This was a request I'd made to Guylain many years ago in the early days of BYE when I was doing lunar eclipse photography and needed to bracket across a wide range.  Unfortunately it doesn't look like it ever came to fruition.  At least it wasn't there the last time I tried to use BYE for the Mercury transit and had random clouds to deal with.  All it really needs is an option to iterate through a sequence list taking one exposure of each setting at a time rather than all exposures of the first followed by all of the second, etc.  It's not exactly a complicated change.  Sequence Generator Pro WILL do this, so that may be what I'll be using for my Canon too, although that will probably mean using two laptops!  It's unfortunate it's not available, but maybe he'll see this and put out a quick update.

Beo

[astroman133]

Beowulf,

I looked at the Feature Suggestion Box forum and did not see any old exposure bracketing suggestions in the archives.

There are a couple of ways that come to mind for how to implement exposure bracketing.

One way is for BYE to handle setting up all the bracketing logic in BYE and nothing in the camera. This way will work, but is more involved to program.

Another way is to use the camera's ability to do bracketing and expose the bracketing choices to the user. Then, with a bracketing option selected by the user 3 images will be shot by BYE for each exposure that is defined in the capture plan, the normal exposure, the lighter exposure and the darker exposure. However, this has a vulnerability in that if there is a problem, BYE could get out of sync with the camera and not all expected exposures would be shot.

 

[jforkner]

1 hour ago, Lord Beowulf said:

This was a request I'd made to Guylain many years ago in the early days of BYE when I was doing lunar eclipse photography and needed to bracket across a wide range.  Unfortunately it doesn't look like it ever came to fruition.  At least it wasn't there the last time I tried to use BYE for the Mercury transit and had random clouds to deal with.  All it really needs is an option to iterate through a sequence list taking one exposure of each setting at a time rather than all exposures of the first followed by all of the second, etc.  It's not exactly a complicated change.  Sequence Generator Pro WILL do this, so that may be what I'll be using for my Canon too, although that will probably mean using two laptops!  It's unfortunate it's not available, but maybe he'll see this and put out a quick update.

Beo

 

16 minutes ago, astroman133 said:

Beowulf,

I looked at the Feature Suggestion Box forum and did not see any old exposure bracketing suggestions in the archives.

There are a couple of ways that come to mind for how to implement exposure bracketing.

One way is for BYE to handle setting up all the bracketing logic in BYE and nothing in the camera. This way will work, but is more involved to program.

Another way is to use the camera's ability to do bracketing and expose the bracketing choices to the user. Then, with a bracketing option selected by the user 3 images will be shot by BYE for each exposure that is defined in the capture plan, the normal exposure, the lighter exposure and the darker exposure. However, this has a vulnerability in that if there is a problem, BYE could get out of sync with the camera and not all expected exposures would be shot.

 

I'm confused by these last two responses.  BYE can do AEB if set in the camera and the appropriate number of exposures are set in the capture plan.

Jack

[astroman133]

Jack,

When Beowulf said that his previous suggestion was to support "bracketing across a wide range". I assumed that he wanted a greater capability to do bracketing than what the camera and BYE currently support. if this were implemented, I could envision that BYE's capture plan would support user definition of how exactly to bracket...For example, shoot 7 exposures with a 1/3 stop variation between them. This is more that what the cameras can support and would have to be handled completely by BYE.

What I was suggesting was that working with the camera would be a bit more limited, but would work with the camera's properties that are exposed by the SDK for applications to use.

Your investigations have shown that it is possible to do bracketing today, but you have to do everything manually. You have to enable bracketing in the camera's controls. You have to create a capture plan that has exposures grouped in 3's so it is designed to be used with bracketing. This could be extended so that BYE would allow you to turn bracketing on or off in the camera and to set how much the under and over exposed images are adjusted from the normal. Then when bracketing is turned on, 3 exposures could be taken for each single exposure defined in the capture plan. To my way of thinking, this would make bracketing simpler to use. It would allow you to use the same capture plan both with and without bracketing. It would also allow you to easily change the bracketing adjustment and re-execute the capture plan.

 

[s3igell]

Several of the newer Enthusiast / Prosumer models from Canon (70D/80D, 6D/7D/7DmkII, etc) do allow for In-Camera definition of both the Count of Exposures in a Bracket (3,5,7) and the Exposure Gap in F-Stops.  Most of the recent Entry-level Canons also include the latter feature.  So there is broad support for AEB in general.

My experience with 550D, 60D, 7DmkII is that AEB is supported in Av, Tv, and Manual - but NOT in Bulb.  Luckily the current AEB for Eclipse discussion is unlikely to need any AEB Exposures over the 30sec limit of Manual mode.

An additional problem, however, is that several of the newer DSLRs fail to support Capture-to-Card via the SDK - meaning Short Exposures separated by 5-10sec of Download even if all settings are tweaked to minimize the BYE Between-Shot Processing.

[astroman133]

Interesting! My T5i only supports 3 images, but does allow adjustment of the amount of the gap, in stops. The fact that the behavior of the newer/higher-end cameras is different makes it difficult for a 3rd party app to make use of it, without knowing details about each camera.

I will be shooting RAW, only to the card, for the eclipse. To substitute for bracketing, I will be shooting shorter exposures and stretching them slightly, as necessary. That will allow me to capture exposures that are closer together. I am still tweaking it, but my current capture plan has close to 100 exposures in it.

 

[Lord Beowulf]

14 hours ago, astroman133 said:

Beowulf,

I looked at the Feature Suggestion Box forum and did not see any old exposure bracketing suggestions in the archives.

There are a couple of ways that come to mind for how to implement exposure bracketing.

One way is for BYE to handle setting up all the bracketing logic in BYE and nothing in the camera. This way will work, but is more involved to program.

Another way is to use the camera's ability to do bracketing and expose the bracketing choices to the user. Then, with a bracketing option selected by the user 3 images will be shot by BYE for each exposure that is defined in the capture plan, the normal exposure, the lighter exposure and the darker exposure. However, this has a vulnerability in that if there is a problem, BYE could get out of sync with the camera and not all expected exposures would be shot.

 

There was no forum back when Guylain first released BYE and when I first bought it.  So no, you won't see the suggestion there, since it was quite a few years before this website and the forum came into being.  As far as the bracketing, I'm not sure you're realizing the range of exposures involved in covering an eclipse.  The variability of haze and intermittent clouds make having even more dynamic range important.  Thus, I'm typically running across 5-10 stops rather than just three.  At any rate, what I'm looking for isn't to use the bracketing function of the camera or restrict the exposure in any way.  What I want is the ability to run the image sequence in a loop, taking one exposure with each setting in the list each time through the list.  What those settings are is immaterial to the function, which is quite basic.  As mentioned previously, this is a common feature in other astrophotography sequencing software, but it's just missing from BYE.  

Beo

[admin]

If it helps Jerry Lodriguss will be using BYE to image the eclipse and he told me last week that he will be using 32 plan item lines for the complete eclipse and I do not believe he is using exposure bracketing.

[astroman133]

Beo,

I do understand about the range of exposures needed to shoot an eclipse. My exposure plan has exposures ranging from 1/1000th of a second during the partial phases to 2 seconds at totality, all at ISO 100. The exposures are too closely spaced to do any type of looping as you suggest, or even bracketing.

It appears that your suggestion is quite different from the OP's request for BYE to support exposure bracketing. I suggest that you move your suggestion to the Feature Suggestion Box forum. There are a number of posts there that present suggestions for adding functionality and complexity to the capture plan.