Quick Astrotracer Question

**mattt** · 04-15-2017, 10:02 PM

Hey folks
I've been playing with the K-1 Astro feature, after having been pretty functional with the OGPS-1. I preface the following by saying the manual is pretty vague - I looked but could not find any hint to my question below.
The menu buttons are pretty intuitive to make it go, I really like the quick access to the precise calibration, but I've been confused a little bit by the green button functionality. It seems it toggles Bulb mode and on board timer.
Is this feature so that someone can used a wired release with a timer?

I of would normally use the Astrotracer timer and a wireless remote. I've been a little confused as to whether the Astrotracer feature is actually engaged when the display shows "bulb".

TIA

jhankins · 04-15-2017, 11:10 PM

On my K-50 with latest firmware and O-GPS1, I believe the green button lets me toggle between astrotracer or bulb. The screen shows "Astrotracer" when the mode dial is set to B, but if I then press the green button, the screen changes to say "Astrotracer". Don't know if that helps or not.

-Jonathan

Adam · 04-15-2017, 11:36 PM - **1 Like**

Originally posted by mattt

Hey folks
I've been playing with the K-1 Astro feature, after having been pretty functional with the OGPS-1. I preface the following by saying the manual is pretty vague - I looked but could not find any hint to my question below.
The menu buttons are pretty intuitive to make it go, I really like the quick access to the precise calibration, but I've been confused a little bit by the green button functionality. It seems it toggles Bulb mode and on board timer.
Is this feature so that someone can used a wired release with a timer?

I of would normally use the Astrotracer timer and a wireless remote. I've been a little confused as to whether the Astrotracer feature is actually engaged when the display shows "bulb".

TIA

Either the green button or exposure compensation button allows you to toggle the astrotracer while in bulb mode- I can't remember which, but you should see the astrotracer icon next to it, not the self timer icon. You will see the "B" icon replaced with the astrotracer icon on the status screen / in live view when the astrotracer is on.

The other button switches between standard bulb mode and timed bulb mode. With a recent firmware update, bulb mode now allows you to select shutter speeds >30s and <20minutes (this is what might be throwing you off). When the astrotracer is on, you should only be able to select shutter speeds <5minutes (sometimes less than that depending on the focal length/location).

**jbinpg** · 04-16-2017, 12:55 PM

Astrotracer mode controls the exposure. If you toggle to Bulb mode, then by definition you are no longer in Astrotracer mode/

jeantree · 07-14-2017, 08:13 PM

Originally posted by Adam

Either the green button or exposure compensation button allows you to toggle the astrotracer while in bulb mode- I can't remember which, but you should see the astrotracer icon next to it, not the self timer icon. You will see the "B" icon replaced with the astrotracer icon on the status screen / in live view when the astrotracer is on.

The other button switches between standard bulb mode and timed bulb mode. With a recent firmware update, bulb mode now allows you to select shutter speeds >30s and <20minutes (this is what might be throwing you off). When the astrotracer is on, you should only be able to select shutter speeds <5minutes (sometimes less than that depending on the focal length/location).

Are you saying after calibrating and turning Astrotracer on, that I can hit the exposure compensation button to set the time of exposure, but it's still in bulb mode AND thus Astrotracer? That's awesome if true, since unlike most of the world, I don't carry a cell phone around to use as a timer in the dark! I have a new K70, and just tried the astrotracer out this evening. I noticed when I hit the green button, astrotracer turned off and I could set the shutter for over 30 seconds. Please let me know if this is what you mean.

Adam · 07-15-2017, 03:43 AM

Originally posted by jeantree

Are you saying after calibrating and turning Astrotracer on, that I can hit the exposure compensation button to set the time of exposure, but it's still in bulb mode AND thus Astrotracer? That's awesome if true, since unlike most of the world, I don't carry a cell phone around to use as a timer in the dark! I have a new K70, and just tried the astrotracer out this evening. I noticed when I hit the green button, astrotracer turned off and I could set the shutter for over 30 seconds. Please let me know if this is what you mean.

The astrotracer has a theoretical maximum of 300s, but in practice you'll get good results in the 60-120s range, depending on the lens, calibration, and location.

Shutter speeds up to 20 minutes are selectable in B mode while the astrotracer is off. So, for astrotracer use alone I'd say having the IR remote is handy, but it's no longer a necessity for getting long exposure shots.

MaineNative · 07-18-2017, 04:24 PM

I was confused by the green button as well. If you have turned on the GPS with the button on the top of the camera and calibrate, the camera is in Astrotracer mode when you go to Bulb mode. You will see an icon in the bottom right of the screen that says to press the green button to turn off Astrotracer. The problem comes if you want to use the timer in Bulb mode, but want to keep Astrotracer off. (Such as trying to take a foreground shot to go with the Astrotracer stars.). If you just hit the green button to turn off Astrotracer, you go to bulb mode with no timer. However, I discovered if you are in Astrotracer mode, hit the Info button and turn off Astrotracer on the Info/status screen, you will be in Bulb mode with the timer.

I have been using Mirror Up and 2 sec timer with an IR remote for Astrotracer and it works well.

jeantree · 07-19-2017, 06:16 AM

Ok, that helps too! Why isn't any of this documented in the manual or somewhere!? It's just trial and error!

MaineNative · 07-19-2017, 07:37 PM - **1 Like**

The Bulb timer was added in one of the firmware updates, so it wasn't in the manual. It wasn't documented well in the firmware update, so it was mostly trial and error thinking about it during the 60 to 120 seconds during each night exposure. Lots of time to ponder stuff with Astrotracer... even more if you do long exposure noise reduction!

04-15-2017, 10:02 PM	#1
mattt Site Supporter Join Date: Feb 2011 Location: Niagara Photos: Gallery \| Albums Posts: 3,907	Quick Astrotracer Question Hey folks I've been playing with the K-1 Astro feature, after having been pretty functional with the OGPS-1. I preface the following by saying the manual is pretty vague - I looked but could not find any hint to my question below. The menu buttons are pretty intuitive to make it go, I really like the quick access to the precise calibration, but I've been confused a little bit by the green button functionality. It seems it toggles Bulb mode and on board timer. Is this feature so that someone can used a wired release with a timer? I of would normally use the Astrotracer timer and a wireless remote. I've been a little confused as to whether the Astrotracer feature is actually engaged when the display shows "bulb". TIA

04-15-2017, 11:36 PM - 1 Like	#3
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,597	Originally posted by mattt Hey folks I've been playing with the K-1 Astro feature, after having been pretty functional with the OGPS-1. I preface the following by saying the manual is pretty vague - I looked but could not find any hint to my question below. The menu buttons are pretty intuitive to make it go, I really like the quick access to the precise calibration, but I've been confused a little bit by the green button functionality. It seems it toggles Bulb mode and on board timer. Is this feature so that someone can used a wired release with a timer? I of would normally use the Astrotracer timer and a wireless remote. I've been a little confused as to whether the Astrotracer feature is actually engaged when the display shows "bulb". TIA Either the green button or exposure compensation button allows you to toggle the astrotracer while in bulb mode- I can't remember which, but you should see the astrotracer icon next to it, not the self timer icon. You will see the "B" icon replaced with the astrotracer icon on the status screen / in live view when the astrotracer is on. The other button switches between standard bulb mode and timed bulb mode. With a recent firmware update, bulb mode now allows you to select shutter speeds >30s and <20minutes (this is what might be throwing you off). When the astrotracer is on, you should only be able to select shutter speeds <5minutes (sometimes less than that depending on the focal length/location). Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

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04-15-2017, 11:10 PM	#2
jhankins Forum Member Join Date: Jan 2016 Photos: Gallery \| Albums Posts: 84	On my K-50 with latest firmware and O-GPS1, I believe the green button lets me toggle between astrotracer or bulb. The screen shows "Astrotracer" when the mode dial is set to B, but if I then press the green button, the screen changes to say "Astrotracer". Don't know if that helps or not. -Jonathan

04-16-2017, 12:55 PM	#4
jbinpg Site Supporter Join Date: Mar 2008 Location: Prince George, BC Photos: Gallery \| Albums Posts: 3,546	Astrotracer mode controls the exposure. If you toggle to Bulb mode, then by definition you are no longer in Astrotracer mode/

07-14-2017, 08:13 PM	#5
jeantree Senior Member Join Date: Jan 2011 Location: Missouri Photos: Gallery Posts: 221	Originally posted by Adam Either the green button or exposure compensation button allows you to toggle the astrotracer while in bulb mode- I can't remember which, but you should see the astrotracer icon next to it, not the self timer icon. You will see the "B" icon replaced with the astrotracer icon on the status screen / in live view when the astrotracer is on. The other button switches between standard bulb mode and timed bulb mode. With a recent firmware update, bulb mode now allows you to select shutter speeds >30s and <20minutes (this is what might be throwing you off). When the astrotracer is on, you should only be able to select shutter speeds <5minutes (sometimes less than that depending on the focal length/location). Are you saying after calibrating and turning Astrotracer on, that I can hit the exposure compensation button to set the time of exposure, but it's still in bulb mode AND thus Astrotracer? That's awesome if true, since unlike most of the world, I don't carry a cell phone around to use as a timer in the dark! I have a new K70, and just tried the astrotracer out this evening. I noticed when I hit the green button, astrotracer turned off and I could set the shutter for over 30 seconds. Please let me know if this is what you mean.

07-15-2017, 03:43 AM	#6
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,597	Originally posted by jeantree Are you saying after calibrating and turning Astrotracer on, that I can hit the exposure compensation button to set the time of exposure, but it's still in bulb mode AND thus Astrotracer? That's awesome if true, since unlike most of the world, I don't carry a cell phone around to use as a timer in the dark! I have a new K70, and just tried the astrotracer out this evening. I noticed when I hit the green button, astrotracer turned off and I could set the shutter for over 30 seconds. Please let me know if this is what you mean. The astrotracer has a theoretical maximum of 300s, but in practice you'll get good results in the 60-120s range, depending on the lens, calibration, and location. Shutter speeds up to 20 minutes are selectable in B mode while the astrotracer is off. So, for astrotracer use alone I'd say having the IR remote is handy, but it's no longer a necessity for getting long exposure shots.

07-18-2017, 04:24 PM	#7
MaineNative Senior Member Join Date: Jul 2017 Photos: Gallery Posts: 280	I was confused by the green button as well. If you have turned on the GPS with the button on the top of the camera and calibrate, the camera is in Astrotracer mode when you go to Bulb mode. You will see an icon in the bottom right of the screen that says to press the green button to turn off Astrotracer. The problem comes if you want to use the timer in Bulb mode, but want to keep Astrotracer off. (Such as trying to take a foreground shot to go with the Astrotracer stars.). If you just hit the green button to turn off Astrotracer, you go to bulb mode with no timer. However, I discovered if you are in Astrotracer mode, hit the Info button and turn off Astrotracer on the Info/status screen, you will be in Bulb mode with the timer. I have been using Mirror Up and 2 sec timer with an IR remote for Astrotracer and it works well.

07-19-2017, 06:16 AM	#8
jeantree Senior Member Join Date: Jan 2011 Location: Missouri Photos: Gallery Posts: 221	Ok, that helps too! Why isn't any of this documented in the manual or somewhere!? It's just trial and error!

07-19-2017, 07:37 PM - 1 Like	#9
MaineNative Senior Member Join Date: Jul 2017 Photos: Gallery Posts: 280	The Bulb timer was added in one of the firmware updates, so it wasn't in the manual. It wasn't documented well in the firmware update, so it was mostly trial and error thinking about it during the 60 to 120 seconds during each night exposure. Lots of time to ponder stuff with Astrotracer... even more if you do long exposure noise reduction!