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auto bulb ramping tutorial to go from night to day?

I've read through the tutorial for auto bulb ramping from day to night, but I work late nights and usually don't set-up until midnight and need a way to go from night to day. I tried emulating the other tutorial but didn't have any luck. Is there something special that needs to be done to set up for a night to day bramping?

Hey Brian,


Someone else just said they had trouble with night to day -- so there might be an issue.  I had tested it early on when first implementing the feature, but I will admit it's not nearly as tested as day-to-night as I'm not usually up that early. :)


What were your results when you tried it?


I'll give it a try this week and report back -- sorry for any trouble you're experience! 


Thanks,


Elijah


Has there been any resolution on this?  I do not see any options for reversing the auto bulb ramping, like setting the intinal exposure at 30 secs and ending at 1/20th.

Should you do a manual bulb ramp?

 

 

Hi Martin,


The online documentation for Timelapse+ states that the night-to-day feature is still in the development stage, so it's not presently working at the moment: http://www.timelapseplus.com/compatability/.


However, there have been instances when customers have achieved good results with night-to-day bulb-ramping. The main problem with this feature is that the light sensor isn't able to detect the low darkness levels at night to provide the necessary exposures settings. With day-to-night transitions, the algorithm is simple, as the exposure ramps down to at a programmed rate to a certain "Night Target" level, which is below what the light sensor can detect. But with night-to-day transitions, the program doesn't have a reference point to start from, so bulb-ramping can't start until the light level is high enough for the sensor to detect.


You'd probably have to start you camera in manual mode until light is detectable by the TL+ and a 2 second bulb time can be used (maximum StartTv for the TL+). If you are able to use a 2 second bulb time, it may be possible to get night-to day bulb-ramping to work by setting the "Night Target" setting to the darkest setting (Milky Way), and adjust the "Bramp Factor" setting to the highest possible value (3). This will trigger the ramping algorithm at the slightest change in light. Then run the TL+ in bulb-ramping mode, and check to see when the exposure starts increasing. Then adjust the "Bramp Factor" down and adjust "ISO Max" and "Aperture Min" until the first few photos look acceptable to the point where the light level is detectable.


The only way I know of to get the TL+ to start at 30 seconds is to start the bulb-ramping in the evening when it's still daylight. A "Night Target" should be set according to the expected darkness level. When the night target is reached, the exposure would be around 30 seconds. Just continue bulb-ramping from there until light is detectable by the TL+. There might be exposure problems for this time period, but it may be possible to correct them by adjusting "Bramp Factor", "ISO Max", and "Aperture Min".


Regards,
James

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