Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-24-2015, 09:09 AM   #16
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 26,158
QuoteOriginally posted by Spodeworld Quote
but if it is facing away, the thyristor would not be aware of that and would not compensate for the additional power required when bouncing or modifying the flash.
...memo to self: Always make sure the sensor on the AF280T flash is facing the subject when being used as an off-camera slave in auto mode. (That is, of course, the sole use case where the above would be a concern.)


Steve

06-24-2015, 09:15 AM   #17
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 26,158
QuoteOriginally posted by zeds Quote
i think don't to use.,.,
make give not good result.,.,

My experience has been that the AF280T works very well and gives good results equivalent to my very expensive Sigma EF610 DG Super. In some situations with A-series lenses, it works better. With lenses lacking the "A" contacts, it is superior.


Steve
06-24-2015, 09:24 AM   #18
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 26,158
QuoteOriginally posted by Spodeworld Quote
that the thyristor is working realtime
QuoteOriginally posted by TedH42 Quote
Exactly - the realtime measurement of the light as the flash is generating it IS its "auto" functionality.
Yes (again ), the measurement is done in real time. The sensor measures the flash illumination from the subject and attenuates the flash duration* to provide appropriate exposure. The way it works is really quite elegant and gives results similar to if you were to use a flash meter. In many ways, it mirrors the true TTL flash automation found on the Super Program, LX, and other Pentax bodies the AF280T was designed for. BTW...one of the best things is that it works well off-camera (with appropriate trigger), even when the flash is closer or further away than the camera.


Steve

* This may be readily observed by doing a test flash at both near and distant subjects. The duration for the distant subject is observably longer and the time for the flash to recharge is also longer. When up close, the time to recharge is almost instantaneous.

Last edited by stevebrot; 06-24-2015 at 09:30 AM.
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!
af280t, flash, flash with pentax, kx, pentax, pentax af280t flash
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
using pentax 500 ftz flash on kx camera Unregistered Visitors' Center 2 08-01-2011 08:52 PM
Help with Kx and using the flash of camera paulette1979 Flashes, Lighting, and Studio 9 07-17-2011 06:22 PM
For Sale - Sold: Pentax k-x with split image focusing screen, Pentax-M 200mm f4, af280t (CONUS) acrollet Sold Items 6 05-05-2011 02:55 PM
For Sale - Sold: [US] Pentax Flash AF280T with Accessories SOldBear Sold Items 9 02-24-2010 01:13 PM
For Sale - Sold: Pentax AF280T Flash With Off-Camera Cord GaryML Sold Items 10 02-02-2009 07:58 PM



All times are GMT -7. The time now is 05:27 AM. | See also: NikonForums.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