Exposure value not stable in Bulb Mode...

kamayok3 · 01-21-2013, 07:22 PM

Hi all,

Recently I bought a bulb ramping device for my K5 on timelapse purposes. But after few testing, i found out that my K5 always gave me unstable exposure value in Bulb mode. For an example, 1.024s...1.003s...1.056s....1.068s...1.124s....and from time to time. Quite disappointing.

Something strange is when i use this device on my K100DS, it can ramp it perfectly.

Anybody have an idea what is it going on in my k5? Does it meter in Bulb mode? Strange!

Regards,

Tommy

Anvh · 01-21-2013, 07:38 PM

How can it meter in blub mode if it doesnt know the exposure time?

Ole · 01-21-2013, 07:40 PM

No, the camera doesn't meter in bulb mode. The shutter is open for as long as the shutter butten is held down.

kamayok3 · 01-21-2013, 07:50 PM

I can set a specific shutter speed in the controller, let say 1sec exposure in bulb mode. So, the camera will only expose 1sec. But my question is how come K5 shutter speed keep fluctuating in bulb mode eventhough already set to 1sec?

P/S: that controller can actually do something called shutter monitoring.

thanks

stevebrot · 01-21-2013, 08:50 PM

I would suspect the controller and not the camera.

In bulb, the shutter stays open as long as the circuit stays open...or the battery dies.

What controller (intervalometer) are you using?

Steve

Ole · 01-21-2013, 08:51 PM

That must be the controller that varies the time. But it is not a lot as per your numbers, not something you'll notice in the exposured image.

kamayok3 · 01-21-2013, 08:52 PM

Alright, then I got nothing to ask anymore. Thanks everyone.

One last thing I wish to mention. Same setting in the timelapse controller used it on K100DS and K5, which K100DS can ramp it perfectly. While K5 is the unstable one.

stevebrot · 01-21-2013, 10:01 PM

Originally posted by kamayok3

Alright, then I got nothing to ask anymore. Thanks everyone.

One last thing I wish to mention. Same setting in the timelapse controller used it on K100DS and K5, which K100DS can ramp it perfectly. While K5 is the unstable one.

Might it be that your controller is made to work with the K100DS and not with the K5?

Steve

kamayok3 · 01-21-2013, 10:16 PM

Maybe one thing i can think of is K5 pc sync port giving wrong value.

Fogel70 · 01-21-2013, 11:09 PM

Originally posted by kamayok3

Alright, then I got nothing to ask anymore. Thanks everyone.

One last thing I wish to mention. Same setting in the timelapse controller used it on K100DS and K5, which K100DS can ramp it perfectly. While K5 is the unstable one.

How does the shutter monitoring work? Are you sure the shutter monitoring is in use with K100DS?

kamayok3 · 01-22-2013, 12:22 AM

The controller works with PC sync port that detect the shutter open and close time. Then on the K100DS, I will need to use a Flash Hot Shoe PC Sync Cord Socket Adapter. That's all.

**fs999** · 01-22-2013, 02:21 AM

What values are in the exif data ?

stuskier · 02-16-2013, 11:55 PM

Kamayok3, what make and model device are you using?

Dr_who · 02-17-2013, 12:49 AM

At only one second can't you use the built in Intervalometer?

01-21-2013, 07:22 PM	#1
kamayok3 Forum Member Join Date: Apr 2010 Posts: 90	Exposure value not stable in Bulb Mode... Hi all, Recently I bought a bulb ramping device for my K5 on timelapse purposes. But after few testing, i found out that my K5 always gave me unstable exposure value in Bulb mode. For an example, 1.024s...1.003s...1.056s....1.068s...1.124s....and from time to time. Quite disappointing. Something strange is when i use this device on my K100DS, it can ramp it perfectly. Anybody have an idea what is it going on in my k5? Does it meter in Bulb mode? Strange! Regards, Tommy

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01-21-2013, 07:38 PM	#2
Anvh Veteran Member Join Date: Sep 2011 Posts: 4,616	How can it meter in blub mode if it doesnt know the exposure time?

01-21-2013, 07:40 PM	#3
Ole Administrator Join Date: Sep 2006 Location: Copenhagen, Denmark Photos: Gallery \| Albums Posts: 4,408	No, the camera doesn't meter in bulb mode. The shutter is open for as long as the shutter butten is held down.

01-21-2013, 07:50 PM	#4
kamayok3 Forum Member Join Date: Apr 2010 Posts: 90 Original Poster	I can set a specific shutter speed in the controller, let say 1sec exposure in bulb mode. So, the camera will only expose 1sec. But my question is how come K5 shutter speed keep fluctuating in bulb mode eventhough already set to 1sec? P/S: that controller can actually do something called shutter monitoring. thanks

01-21-2013, 08:50 PM	#5
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	I would suspect the controller and not the camera. In bulb, the shutter stays open as long as the circuit stays open...or the battery dies. What controller (intervalometer) are you using? Steve

01-21-2013, 08:51 PM	#6
Ole Administrator Join Date: Sep 2006 Location: Copenhagen, Denmark Photos: Gallery \| Albums Posts: 4,408	That must be the controller that varies the time. But it is not a lot as per your numbers, not something you'll notice in the exposured image.

01-21-2013, 08:52 PM	#7
kamayok3 Forum Member Join Date: Apr 2010 Posts: 90 Original Poster	Alright, then I got nothing to ask anymore. Thanks everyone. One last thing I wish to mention. Same setting in the timelapse controller used it on K100DS and K5, which K100DS can ramp it perfectly. While K5 is the unstable one.

01-21-2013, 10:01 PM	#8
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by kamayok3 Alright, then I got nothing to ask anymore. Thanks everyone. One last thing I wish to mention. Same setting in the timelapse controller used it on K100DS and K5, which K100DS can ramp it perfectly. While K5 is the unstable one. Might it be that your controller is made to work with the K100DS and not with the K5? Steve

01-21-2013, 10:16 PM	#9
kamayok3 Forum Member Join Date: Apr 2010 Posts: 90 Original Poster	Maybe one thing i can think of is K5 pc sync port giving wrong value.

01-21-2013, 11:09 PM	#10
Fogel70 Pentaxian Join Date: Sep 2009 Location: Stockholm, Sweden Photos: Albums Posts: 3,062	Originally posted by kamayok3 Alright, then I got nothing to ask anymore. Thanks everyone. One last thing I wish to mention. Same setting in the timelapse controller used it on K100DS and K5, which K100DS can ramp it perfectly. While K5 is the unstable one. How does the shutter monitoring work? Are you sure the shutter monitoring is in use with K100DS?

01-22-2013, 12:22 AM	#11
kamayok3 Forum Member Join Date: Apr 2010 Posts: 90 Original Poster	The controller works with PC sync port that detect the shutter open and close time. Then on the K100DS, I will need to use a Flash Hot Shoe PC Sync Cord Socket Adapter. That's all.

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01-22-2013, 02:21 AM	#12
fs999 Loyal Site Supporter Join Date: Jul 2008 Location: Luxembourg Photos: Gallery Posts: 8,628	What values are in the exif data ?

02-16-2013, 11:55 PM	#13
stuskier New Member Join Date: Nov 2009 Location: Olympia, Washington, USA Posts: 13	Kamayok3, what make and model device are you using?

02-17-2013, 12:49 AM	#14
Dr_who Veteran Member Join Date: Jun 2009 Location: Edmonton, Alberta, Canada Photos: Gallery \| Albums Posts: 777	At only one second can't you use the built in Intervalometer?