Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
11-15-2010, 04:00 PM   #1
Junior Member




Join Date: Sep 2007
Location: Long Island NY
Photos: Gallery
Posts: 29
Fill flash....

Hi,
I have a K20D with a problem. I have been unable to take pictures reliably using fill flash.
Both with my Pentax 360 flash and thyristor flash it is a hit or miss proposition.
I have shot a wedding outside with the camera set to x-sync but the flash would not fire. When inside at times the flash would sometimes simply stop firing. The camera and the flash were powerer cycled to no avail (frames were black or horribly underexposed. Yes the batteries were fresh and changed.).
Today I tried a thyristor flash and it fired twice and on the same subject it simply refused to fire again several times. Nothing changed other than the aperture which I changed to reduce over exposure. (Sunpak 611 with Wein SS). Flash works fine in test mode.
Camera was updated to latest SW. The camera was purchased new by me.
It looks like the camera doesn't supply contact closure reliably.
The camera was never exposed to high voltage flashes.
Anyone else run into this problem?
Sorry for the rant.
Rudi

11-15-2010, 07:25 PM   #2
Site Supporter
Nick Siebers's Avatar

Join Date: Jun 2008
Location: Madison, WI
Photos: Gallery | Albums
Posts: 2,152
Hi Rudi -

I have had a similar problem with an accessory flash, where suddenly it would not fire and I could not get it to for some time. Both times this has happened I eventually realized I had bumped my shutter speed higher than 180 by accident. I was using M mode, that shouldn't happen in X mode. But maybe you want to check your shots just to be sure.
11-16-2010, 01:23 AM   #3
Pentaxian
hoanpham's Avatar

Join Date: Nov 2009
Location: Strand
Photos: Gallery | Albums
Posts: 1,366
Hi. I am using k20 too. For me, manual is the only consistent way to use. p-ttl results were not as I expected and also very difficult to calculate flash power when they adjust only single channel with +- ev steps instead og power settings 1/1, 1/2, 1/4 etc. I haven't time to explore p-ttl to get it consistent and gave up.

I set up the flashes to cover a large area, with different power settings, and exploit window light, white surfaces as much as possible. I use 1/125 as max synch speed. it's the most reliable. 1/180 as max only with cable or hotshoe. 1/160 is highly unreliable with radio sync.

Best regards
11-16-2010, 06:01 AM   #4
Junior Member




Join Date: Sep 2007
Location: Long Island NY
Photos: Gallery
Posts: 29
Original Poster
Nick,

Thanks for the quick response.
Nope, not the problem. At the wadding and my test yesterday I was sure of my x-sync setting, yesterday was specific TO test the flash to see if the if the potato masher would be more reliable, it was not. I did change the aperture from the setting selected on the controller. Later that day the thing seemed ok'er, less failure to fire and some over exposures probably my fault I was playing with the output levels.

The wadding was shot with the 360 in p-ttl mode (later I learned that hss could/would solve the fill problem). I used the p-ttl in every mode imaginable from green to x-sync, when it failed it wouldn't work inside or outside. The equally unexpected it would work again but exposures were inconsistent..

Today I should get a sunpak 544, (God bless e-bay, 2 super flashes for less than 75 bucks)

Seems to me if the K20 thinks the light is good, or is in a hissy mood, it won't use the flash no matter what you want.

Oh yes, The flash setting is for simply flash, no redeye correction etc, or what, just flash.
The manual is also not forth coming on the issue of fill flash without a Pentax flash. Seems the camera is de boss no matter what.

Rudi

11-16-2010, 06:26 AM   #5
Junior Member




Join Date: Sep 2007
Location: Long Island NY
Photos: Gallery
Posts: 29
Original Poster
Hoanphan,

What flash? A Pentax or the like?

I have also looked at the competition: Sigma, Metz, etc, even the Pentax 540, but paying between 2 an 400 dollars seems a bit steep; without even knowing if the results will be better. Being old (very OLD) school I am not intimidated by guide numbers, my very first electronic flash was a Braun Hobby EF3, Which was sent to the great flash heaven in sky, along with my ORIGINAL Strobonar (and some Spiratone units) I had. Both now worth money as collector items (I still have my early Nikons! and an early 2x3 Speedgraphic).

My impression with P-ttl is also less than enthusiastic. The fact that Pentax won't 'fess up in the voltage limit for the PC, (yes I called them), They advised 24 or 25 volts for the hotshoe and the PC, but the PC could be higher but, well, we won't tell you how high. Very professional. One of the reasons (I had a K100 (what a gem)) I went for the K20 was it did have a pc! But then I couldn't find ANY of my old flashes except a Vivitor 2800 which works ok with the Wein SS,
(I'm almost sorry I didn't go with the other brands as I had boat load (and still do) of lenses bodies and ... well you know.)

Rudi
11-16-2010, 01:26 PM   #6
Pentaxian
hoanpham's Avatar

Join Date: Nov 2009
Location: Strand
Photos: Gallery | Albums
Posts: 1,366
Hi Rudi,

I use whatever flash with manual control, but with one small addition: I use radio trigger: pt-04 sender and double hotshoe receiver, 15 usd a piece on ebay. This will safely connect all my old flashes independent of voltage on the hotshoe.

I tried p-ttl at the beginning, when i got my k20, but gave up, and perhaps never look back. p-ttl may be good for direct lit, but bouncing with different surfaces, some colored, and off-camera, that makes p-ttl short. It's better to have full manual control.

I have 2 sigmas, 530 super, just to be able with hss and second curtain synch in low light. +half dozen other older same guide number, both pentax and other brands, and a pair sunpak pz40 mini flashes (canon e-ttl) but i use manual only. they are small and very handy for back lit or rim light.

Last edited by hoanpham; 11-16-2010 at 01:33 PM.
11-16-2010, 05:23 PM   #7
Forum Member




Join Date: Jan 2009
Location: Central New Jersey
Posts: 97
Thought

Have you tried to use the pop-up flash for fill? Just wondering if the problem happens with the pop up, or if it's only happening when you attach a flash via the shoe?
11-16-2010, 06:56 PM   #8
Site Supporter
GeneV's Avatar

Join Date: Oct 2008
Location: Albuquerque NM
Photos: Albums
Posts: 9,777
QuoteOriginally posted by Rude Quote
Have you tried to use the pop-up flash for fill? Just wondering if the problem happens with the pop up, or if it's only happening when you attach a flash via the shoe?
That use and as a control flash for P-TTL wireless are about the only uses I make of the pop-up flash.

For an external flash, I set the exposure on the camera manually, and use P-TTL for the fill flash.

11-16-2010, 10:13 PM   #9
Veteran Member




Join Date: Jan 2007
Location: Northern California
Posts: 475
Here are some clues and things to check:

Page 145 of the K20D manual:

"Using P-TTL Auto Mode"

'The flash does not discharge when the subject is bright enough when Flash mode is (lightning bolt symbol)A or (lightning bolt symbol) A (redeye symbol). Therefore it may not be suitable for daylight-sync shooting"

"Using High-Speed Flash Sync Mode"

"2. Turn the mode dial and set the exposure mode to TV or M'
"3. Set the external flash sync mode to HS (lightning bolt symbol) (high-speed flash sync).

"High-speed flash sync is only available when the shutter speed is faster than 1/180 sec"

Page 143:

"Trailing Curtain Sync *2"

"*2 Shutter speed of 1/90 or slower"

Note that X sync is fixed at 1/180 second shutter speed.

I use some Nikon flashes in "A" mode on my K20D occasionally, and one time (also a wedding) they behaved as you describe where they would not fire reliably even though they have been modified to only have a center pin. That has never happened before or since and I never figured out what the problem was that day. I suspect that the camera was set for trailing curtain sync.

I think the only daylight fill mode that makes any sense is to shoot in M mode with the flash in HSS and press the green button to set the main exposure, then fire away adjusting flash exposure comp as needed to get the fill you want. Make sure the shutter speed is higher than 1/180 sec.

You could also shoot Tv in HSS, but you have no control of the aperture this way.

Ray
11-17-2010, 01:11 AM   #10
Pentaxian
hoanpham's Avatar

Join Date: Nov 2009
Location: Strand
Photos: Gallery | Albums
Posts: 1,366
I also used the popup as wireless synch together with the 2 sigmas. There are several setting that I found out to be useful:

- popup flash can be turned on/off. When it is turned off on wireless mode, only the external flash is triggered. (**)
- popup flash EV set to approx -2 to fill. For the external sigmas, I have to dial down manually, but instead of power step, I have to use EV steps on these too (*)
- WB when using flash: set as-is, no change.

(*) The sigmas set automatically to 1/4 power at EV=0. I can adjust EV+2 to get full power. However I am used to set the power step manually like 1/1, 1/2, 1/4 etc. But as I mentioned, this mode is highly unreliable flash output. Manual mode gives much better control.

(**) by turn off the popup flash in wireless mode, I mean it is still used to send pulses of light as control signals to the slaves, but the flash is not fired in the picture. You have to let the flash 'popup' to use this mode.

I almost never use popup flash as fill, only on my vacation.

I try to use 1/4 as max, prefer 1/8, and can shoot more than one frame without waiting. When circumstances allow, I bundled 2 flashed in one double hotshoe receiver and set both to 1/8 power to get one 1/4. Power also depends on bounce surface and/or umbrella.

Last edited by hoanpham; 11-17-2010 at 02:25 PM.
11-17-2010, 01:37 AM   #11
Pentaxian




Join Date: Feb 2009
Location: Alameda, CA
Posts: 3,196
QuoteOriginally posted by hoanpham Quote
- popup flash can be turned on/off. When it is turned off on wireless mode, only the external flash is triggered.
This statement may create confusion. In wireless mode, the built-in flash can NOT be turned off completely (at least I haven't figured out how to do it). The built-in flash can be either master (contributing significantly to the exposure) or control (still firing to trigger the external flash(es), but with reduced power thus not contributing significantly to the exposure).
11-18-2010, 02:54 AM   #12
Pentaxian
hoanpham's Avatar

Join Date: Nov 2009
Location: Strand
Photos: Gallery | Albums
Posts: 1,366
QuoteOriginally posted by SOldBear Quote
... or control (still firing to trigger the external flash(es), but with reduced power thus not contributing significantly to the exposure).
No. If you turn it off, the popup will not contributing to the exposure. It is used for control signals only.
11-18-2010, 04:07 AM   #13
Pentaxian
amoringello's Avatar

Join Date: May 2008
Location: Virginia, USA
Photos: Gallery
Posts: 1,427
QuoteOriginally posted by hoanpham Quote
No. If you turn it off, the popup will not contributing to the exposure. It is used for control signals only.
Just remember in order to give that signal, it MUST fire! (how else would the slaves know when to fire?) This final control flash is visible, so there is some potential for contribution to exposure if;
1) the subject is very close to the control flash
2) if the control flash is visible in a reflective object such as a mirror or xmas ornament

In general the main flash is bright enough to cancel out any effect of the control.
But do be aware of the possible caveats.
11-18-2010, 05:38 AM   #14
Pentaxian
hoanpham's Avatar

Join Date: Nov 2009
Location: Strand
Photos: Gallery | Albums
Posts: 1,366
I did test this with the sigmas. The control puls was submited from the popup flash, but it is not contribute to the picture. In low light it also flashes to get focus. Control signals are pre-flash, very short puls (1/1000 sec). It seems to flash together with the main puls, but they are distinct. You can try by turn it 'off' in wireless mode and take picture of the mirror (K20 menu: Flash in wireless mode=off).

I need this option as a backup when my radio trigger is broken or bad battery. Going nowhere without at least one flash with this capability build in. This option had saved me several times.

Correction:
I retest the popup. It is not completely dark, but very dimmed. Tested with 1/64 power external, and the popup is not significant at all. Still direct reflections may have an issue if you absolutely want to avoid the popup to fire.

Amoringello, you ve right.

Last edited by hoanpham; 11-21-2010 at 03:54 AM.
11-19-2010, 07:10 AM   #15
Junior Member




Join Date: Sep 2007
Location: Long Island NY
Photos: Gallery
Posts: 29
Original Poster
Gee, I am overwhelmed by all this response....

I've been playing with the 611 flash and I think part of the problem with that one was that I didn't tighten the sensor on the Wein tight enough, now I can't get the damn thing off - but it flashes better! The 544 hasn't arrived yet, so waiting... maybe today.

I have never used trailing curtain at all. I found out (it pays to read the manual BEFORE the job) about HSS to late. Experimenting with the p-TTL mode it sometimes yields good exposures sometime(mostly) lousy. Bounce was almost always way under exposed. So much for TTL.

On the wedding I had a few totally dark frames which indicated to me that the aperture was set for a flash to never arrived. And, yes, I constantly checked the settings and batteries.... When the flash failed it mattered little whether I was in green, user, P, or X (I didn't think of using the A mode on the flash). Since I used a flash bracket and remote flash cable I could not use the flipup flash, ditto with the Wein and Sunpak 611 or Wein and Vivitar 2800 - the arrival of 544 should eliminate that issue.

At the time I couldn't get the radio (wireless) control system to work either, at least that would have eliminated the remote flash cable. Later I got that to work but oddly the flipup flash must be used. Seems to me the when the radio (wireless) mode is chosen I should have to choice of using the flipup flash or not (unless the camera is the master).

Oy, my head it spins.

Rudi
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, fire, flash, photography, thyristor, times
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fill flash for K10D with AF360 flash unit dichro1 Troubleshooting and Beginner Help 1 12-03-2009 03:08 PM
Fill Flash thrillerb Troubleshooting and Beginner Help 1 03-10-2009 06:35 AM
Fill Flash Paul Hunt Photographic Technique 11 03-04-2009 08:12 AM
Slow flash - fill in flash - k100d soalle Pentax DSLR Discussion 4 06-21-2008 02:06 PM
Fill flash Mark Castleman Pentax DSLR Discussion 26 02-19-2007 11:08 PM



All times are GMT -7. The time now is 10:40 AM. | 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