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Old Jul 29, 2008, 7:43 AM   #11
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Good post Scott,

I don't have a Pentax flash but do with my other system. Well I have several. It is a subject to me that has merit in adding to the joy of photography but to get there has some frustration for most.

I find the reward surpassing the challenge to learn.

Mahalo,

Tom
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Old Jul 29, 2008, 2:55 PM   #12
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nhmom wrote:
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vIZnquest - I am another one perplexed by the flash.* I used my 360 this weekend, but found it caused me more problems than not.* Was photographing cemetery stones in shadows.* I either ended up with black photos or you could tell I used a flash.*
Hi Patty,

If you could post examples (I'd start a new thread), The cause of your problems might be more clear.

I'll try to help with your problems just using conjecture. . . so what I'm posting here might not really help. . .:?:

If the "black photos" are actually very underexposed shots with a bright spot in the frame, then you've just experienced one of the bugs in Pentax's P-TTL implementation. Any direct reflection of the flash from a shiny surface (like polished granite or marble in your case) will cause massive underexposure as the metering system tries to expose the reflection properly. The fix is to either not shoot straight on, or to use the flash off camera so the light from the flash doesn't reflect straight back to the it, thus eliminating the hot spot caused by the reflection.

If you keep your eye glued to the viewfinder during the shot, you can actually see the reflection of the preflash a split second before the VF goes black because the mirror flips up. I've gotten into the habit of looking for this while shooting events, and when I see it, I immediately tell my subjects to hold for a second while I take a couple of steps sideways, and I'll take a second shot. I don't even wait to chimp the first shot to see if it turned out. . .

As far as the ones that did expose, (and I'm guessing these were of older stones that weren't very shiny) -- if "you can tell it's a flash shot" you mean that the subject (or part of it) is a bit blown out, and the background is too dark, then you might want to learn a flash technique called "dragging the shutter" which involves setting your shutter speed and aperture to expose the background correctly, while using the real time metering of P-TTL during the exposure to get a good flash exposure of your subject. If you google "dragging the shutter", you'll probably find a few explanations with samples, but the process (as I use it) is not that difficult.

I virtually always shoot in Av priority, using center weighted, so I use this to meter the background with the flash mounted and turned on (this automatically limits the shutter speed to values that will synch with the flash, giving you a full frame exposure). I relocate the frame so the BG dominates the center area. I note the aperture and shutter speed the camera selects, and then switch to Manual Mode on the mode dial and duplicate those settings for shutter speed and aperture. Reframe the shot, being careful to now have the subject dominate the central area of the frame, and take the shot. P-TTL will cut off the flash to expose the subject properly, and the shutter speed and aperture combo will ensure that the BG is exposed reasonably. Don't be afraid to use a higher ISO (if necessitated by a very dark BG)as the added high ISO noise should be kept to a minimum by a good exposure, and don't be concerned with a comparitively long shutter speed because the flash will freeze any subject motion and camera shake. If you see more BG camera shake blurring than you want, just go to a higher ISO.

You may still get a blown out subject though, and this can usually be cured by using a diffuser or bouncing the flash off a bounce card, or by relocating the flash off camera at an angle. If the subject is evenly overexposed, you can dial in some negative flash compensation in the Fn menu.

I know this sounds really involved, but it's really not that hard. As Tom has stated, learning how the flash system works (including its quirks and limitations), and learning a few "advanced" flash techniques really is worth the effort as it opens up all kinds of possibilities for shots that you'd normally either have to accept mediocre results, or have to walk away from. . . and with digital, you can get the immediate feedback (and the ability to make slight adjustments during the shoot, as needed) that made learning and using flash so difficult and/or expensive with film.

Scott
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Old Jul 29, 2008, 3:38 PM   #13
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Wow Scott, That's a lot of useful info!
I'm having a little trouble from time to time with flash also. Like Patty, sometimes when I use flash, weather pop up or the 540 the photo will come out very very dark or completely black. Other times it comes out perfect!:-? I'll have to go back and see if I saved any examples and post them.
I want to add a big thank you for this post; it's better explained than anything I've read in books or instruction manuals so far!
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Old Jul 30, 2008, 11:29 AM   #14
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Great advice there Scott.

Also, for those who have fordotten it, or never seen it, possibly the best flash thread ever....



http://forums.steves-digicams.com/fo...mp;forum_id=80



Dal

The thread should be a sticky......
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Old Jul 31, 2008, 11:09 PM   #15
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Scott, I believe I am using the same technique (though I did not know a name for it). At least I believe the results would be the same; instead of metering in Av mode, though, I go to manual first and then use the green button to meter the scene and then turn the flash on. This would give the same results right? Just checking, if there is a difference I need to try your method and see if it refines the results any.

Thanks,
Tim
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Old Jul 31, 2008, 11:15 PM   #16
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Hi Tim,

Same results, different way to get there. I like to choose the aperture for DOF and sharpness considerations, so by using AV, I choose the aperture, and let the camera choose the shutter speed in one step, but it all comes down to the same Ev, so it really doesn't matter.

Scott
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Old Aug 1, 2008, 11:36 PM   #17
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Scott - I finally got a chance to try using the A mode today. Knowing how that works sure made it simple. I was able to add my home-made manual extension tube to the Viv 105 macro, add the flash in A mode, set the flash and lens as you said and get reasonable results. It did take a couple of shots to "dial" in the right amount of light, but it was so much simpler than what I had been trying to do. It's accuracy does seem to depend on the subject to a certain extent. But I was really jazzed. I can't thank you enough for explaining it in a way that it made sense to me.
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Old Aug 3, 2008, 9:34 AM   #18
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So after all the help I received on here. I sent a email off to Pentax. I should of called but I have 2 year old twins and being on the phone for any length of time isn't that easy. I have not received a reply from them but I took my camera back into where I bought it (London Drugs) and there is something wrong with the camera (not me, lol) So now I will see if I get a new camera (I sure hope as this one is only a month old) or they insist on fixing it.

Thanks everyone
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Old Aug 3, 2008, 12:48 PM   #19
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Hope you get a new camera soon (or yours fixed). Not surprised by the verdict - what you described didn't sound normal. Good luck with it!
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