Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
10-03-2012, 09:03 AM   #1
Site Supporter
Site Supporter
mattb123's Avatar

Join Date: Apr 2010
Location: Colorado High Country
Photos: Gallery
Posts: 10,872
Couldn't get 1/180s

I was shooting a mountain bike race last weekend and had a remote flash and a Cactus v5 trigger on the camera. I was in a place where the riders would be going pretty fast and I want to get as fast a shutter speed as I could while still triggering the flash. It's my understanding that 1/180s is the maximum sync speed so in manual mode my plan was to shoot at 1/180 but when I tried to set the camera this way I could get 1/160 and then the next click of the dial would go straight to 1/200s. So I shot at 1/160 and the shot turned out fine but I'm wondering why I couldn't select 1/180.
Can anyone tell me for future reference?
The shot was 1/160s, f/10, ISO 80:



10-03-2012, 09:16 AM   #2
Veteran Member




Join Date: Feb 2012
Location: Fredericton, New Brunswick
Photos: Gallery
Posts: 632
There's not actually a way to select 1/180, when you step up to 1/200 with the flash enabled, it fires at 1/180 is all.
10-03-2012, 09:17 AM   #3
Veteran Member
StephenHampshire's Avatar

Join Date: Oct 2009
Location: Winchester
Photos: Gallery | Albums
Posts: 2,523
Check whether you have EV steps set to 1/3 or 1/2 stops. This will affect the values of shutter speed/iso/aperture you will get when adjusting the exposure, whatever mode you are in.
Custom menu 1 item 1 EV steps
10-03-2012, 09:19 AM   #4
Senior Member
pezmaker's Avatar

Join Date: Jul 2011
Location: Madison, WI
Photos: Gallery | Albums
Posts: 276
Sounds like it's because you're set to 1/3 stops for your shutter speed/aperture changes. From https://www.pentaxforums.com/forums/newreply.php?do=newreply&p=1745610

QuoteOriginally posted by ablundon Quote
For most I use 1/3 stops. However, when I use my Cactus V5 triggers I have to switch to 1/2 stops in order to get the 1/180 shutter speed. My K-r doesn't pick up the Cactus as a flash and therefore when on 1/3 stops the shutter speed goes from 1/160 to 1/200. Sync speed is 1/180 (which is a 1/2 stop).


10-03-2012, 09:35 AM   #5
Site Supporter
Site Supporter
mattb123's Avatar

Join Date: Apr 2010
Location: Colorado High Country
Photos: Gallery
Posts: 10,872
Original Poster
Ah! I bet it's the 1/3 stops. I'll check that when I have a chance. Thanks!
10-03-2012, 09:41 AM   #6
Pentaxian
Jean Poitiers's Avatar

Join Date: Apr 2011
Location: Lost in translation ...
Photos: Gallery | Albums
Posts: 18,076
QuoteOriginally posted by mattb123 Quote
Ah! I bet it's the 1/3 stops. I'll check that when I have a chance. Thanks!
Please let us know what you find out ... just curious - J
10-03-2012, 09:55 AM   #7
Pentaxian
johnyates's Avatar

Join Date: Aug 2011
Location: Saskatoon, SK
Photos: Albums
Posts: 1,345
Nice shot.

If your mode dial has an "X" setting, you can use that to get 1/180.

10-03-2012, 11:01 AM   #8
Pentaxian




Join Date: Jun 2010
Location: North Zealand, Denmark
Photos: Gallery | Albums
Posts: 1,516
QuoteOriginally posted by mattb123 Quote

-------my plan was to shoot at 1/180 but when I tried to set the camera this way I could get 1/160 and then the next click of the dial would go straight to 1/200s. So I shot at 1/160 and the shot turned out fine but I'm wondering why I couldn't select 1/180.
Can anyone tell me for future reference?
The shot was 1/160s, f/10, ISO 80:
It really doesn't/shouldn't matter what your EV-stops are. I have my K-5 EV-steps set to 1/3 and it works like this: When I am in M-mode and my external flash is powered on or if my built-in flash is raised then I can dial my way to down to 1/180s and no faster.

On the other hand, if I have set my exposure time to 1/200s or faster and I thereafter power my external flash on or raise the built-in flash, then the shutter speed will automatically jump to 1/180s.

I would believe, that the K-5 interprets a trigger the same way, but it would be interesting to hear what you find out.

By the way: Fine picture with great colours!
10-03-2012, 11:17 AM   #9
Site Supporter
Site Supporter
mattb123's Avatar

Join Date: Apr 2010
Location: Colorado High Country
Photos: Gallery
Posts: 10,872
Original Poster
Thanks for the compliments! I was happy with the shot also.

I just checked the camera and it was indeed set to 1/3 EV steps. Changing it to 1/2 allows me to select 1/180 but of course not 160 anymore, the click below 1/180 is now 1/125 which makes sense.

It seems that the Cactus v5 is not recognized as being a flash by the camera as I can see in the EXIF for that image:

Camera Pentax K-5
Exposure 0.006 sec (1/160)
Aperture f/10.0
Focal Length 33 mm
ISO Speed 80
Exposure Bias 0 EV
Flash Off, Did not fire
10-03-2012, 11:29 AM   #10
Site Supporter
Site Supporter
mattb123's Avatar

Join Date: Apr 2010
Location: Colorado High Country
Photos: Gallery
Posts: 10,872
Original Poster
QuoteOriginally posted by johnyates Quote
Nice shot.

If your mode dial has an "X" setting, you can use that to get 1/180.
I see! I'll try that next time. Thanks for the info!
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, dslr, flash, k-5, k-5 ii, k-5 iis, k5, pentax k-5, shot

Similar Threads
Thread Thread Starter Forum Replies Last Post
Couldn't have done it without you. Dartmoor Dave Welcomes and Introductions 4 08-05-2012 05:08 PM
Couldn't resist greg57 Welcomes and Introductions 3 06-03-2011 12:28 AM
I couldn't Believe this one Fl_Gulfer General Talk 4 05-05-2011 02:40 AM
Picture I Couldn't Take w/my K-7 RonHendriks1966 Pentax K-5 & K-5 II 12 12-29-2010 04:22 PM
Possible Major Constraint on the 1/180s X-Sync Limitation RiceHigh Pentax News and Rumors 177 06-02-2009 12:22 PM



All times are GMT -7. The time now is 09:39 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top