View Full Version : flash and the problem of blinking
Elaine
Dec-15-2006, 12:20 PM
In the last couple of weeks, I've run into a few people who have struggled to keep their eyes open with my internal flash. This made for some frustrating situations when a group shot was being taken and one person always had their eyes closed or at half mast. I know some people have this tendency more than others, and I believe that some flashes cause this more than others. Is this correct? Also, when I do get my external flash, will this issue cease to be a problem or will I just have to wait and see? Does anyone have experience with this?
Thanks in advance!
Elaine
Andy
Dec-15-2006, 12:29 PM
Got Blinkers? (http://www.dgrin.com/showthread.php?t=23576&highlight=blinker) :lol3
GraphyFotoz
Dec-15-2006, 12:30 PM
In the last couple of weeks, I've run into a few people who have struggled to keep their eyes open with my internal flash. This made for some frustrating situations when a group shot was being taken and one person always had their eyes closed or at half mast. I know some people have this tendency more than others, and I believe that some flashes cause this more than others. Is this correct? Also, when I do get my external flash, will this issue cease to be a problem or will I just have to wait and see? Does anyone have experience with this?
Thanks in advance!
Elaine
I always have PPL concentrate on the wall behind me just above the camera or look JUST to the side of the camera.
This seems to help a lot for this situation.
I tend to do the same thing when someone is brave enough to ruin their camera taking a shot of me! :D
The anticipation of the flash causes PPl to do this automatically.
Hope this helps in the future? :dunno
Elaine
Dec-15-2006, 01:17 PM
Thanks for the thread, Andy. I'm glad to hear others have this issue and have resorted to the eye swap!
I'll also try the suggestion about directing people to look slightly off camera.
Any ideas if this will improve with external flash versus internal flash?
Elaine
ziggy53
Dec-15-2006, 01:41 PM
Thanks for the thread, Andy. I'm glad to hear others have this issue and have resorted to the eye swap!
I'll also try the suggestion about directing people to look slightly off camera.
Any ideas if this will improve with external flash versus internal flash?
Elaine
"Auto" flashes have less of a tendancy to do this because they don't "pre-flash", like the Canon E-TTL(-II) and Nikon i-TTL.
Direct flash seems to be more of a problem than bounced or diffused flash (very much my opinion and experience.)
Some people respond to the sound of the mirror slap, before the shutter noise. Backing up can help reduce the impact of the sound.
With groups, I notice some people blink "on cue". If you detect that happening, take the shot when the group is ready, but unsuspecting.
Always take multiple images of groups. I tend to take 1/2 as many shots as people in the shot. (8 people, 4 shots)
You may have to cut-and-paste open eyes as necessary.
ziggy53
sirsloop
Dec-15-2006, 01:52 PM
heh heh... my fiance is another notorious blinker. She catched the E-TTL preflash 75% of the time. I usually tell people before the shot that there will be flash so dont blink! :) If you do the 'ol countdown, try starting at three, and shoot at 1 (instead of 0). I noticed that if you let it go past one, people start to squint a little preparing for the shot. The longer you wait, the more thier eyes close up. Heh heh... maybe on a bunch of friends make them wait it out 5 seconds after zero and take the shot. Most of them are DYING with flash anticipation by then :rofl:rofl:rofl:rofl
TOF guy
Dec-17-2006, 06:11 PM
I know some people have this tendency more than others, and I believe that some flashes cause this more than others. Is this correct? Also, when I do get my external flash, will this issue cease to be a problem ?
The answers are:
- yes (some people blink more easily and more quickly than others)
- no (some flashes do not cause this more than others: it has everything to do with the camera body and nothing to do with the flash)
- no (using an external flash will not solve your problem: again: this is a body related issue).
The only solution is to upgrade to a body with a shorter black-out duration due to mirror slap, so that the subject does not have time to blink between the pre-flashes and the actual shot.
I could give you all the technical details, from what has changed between recent SLRs and dSLRs that make the blinking problem an issue with the latter and not the former, why manufacturers had to introduce new generations of flashes with dSLR (Canon eTTL2, Nikon iTTL), why some dSLRs have this issue and not others with the same flash, etc. But the bottom line is what I've stated: you'll have to change bodies, or shoot entirely in manual mode.
Caveats: I'm very familiar with the Nikon system. I also know enough about Canon gear to state that the above also applies to their cameras, but I can' tell for sure about other manufacturers.
Thierry
dmcreations
Dec-17-2006, 06:59 PM
Yes, that trick has helped me out before too - fire off two or three quick shots of the group by changing your camera's drive mode to rapid-fire. This esp helps with larger groups where you almost always have at least one person blinking.
ziggy53
Dec-17-2006, 07:44 PM
The answers are:
- yes (some people blink more easily and more quickly than others)
- no (some flashes do not cause this more than others: it has everything to do with the camera body and nothing to do with the flash)
- no (using an external flash will not solve your problem: again: this is a body related issue).
The only solution is to upgrade to a body with a shorter black-out duration due to mirror slap, so that the subject does not have time to blink between the pre-flashes and the actual shot.
I could give you all the technical details, from what has changed between recent SLRs and dSLRs that make the blinking problem an issue with the latter and not the former, why manufacturers had to introduce new generations of flashes with dSLR (Canon eTTL2, Nikon iTTL), why some dSLRs have this issue and not others with the same flash, etc. But the bottom line is what I've stated: you'll have to change bodies, or shoot entirely in manual mode.
Caveats: I'm very familiar with the Nikon system. I also know enough about Canon gear to state that the above also applies to their cameras, but I can' tell for sure about other manufacturers.
Thierry
With respect for your views, the only recent dSLR which seems to have a large anecdotal problem with "blinkers" is the Nikon D70. That particular model seems to have a different method of preflash than other Nikon digital SLR cameras and many people comment they can "see" a visible delay from preflash to flash. I haven't noticed it with my father's D70, so I'm not sure.
As I mention above, "Auto" flashes don't have the same problem, and neither do manual flashes (or manual mode), as you agree. So there "are" differences in flashes, because of their technology and features, and an external flash "can" influence the quantity of blinker-less images as a result. You may have meant to say that there is no difference when using an E-TTL (or i-TTL as it applies) based flash, one model flash versus another. In that case I would probably agree.
For what it's worth, I have not detected any serious problems (or differences) using either the Canon dRebel XT/350D or the Canon 1D MKII, as relates to people blinking. (Then again, I almost always use some sort of flash technique other than direct, so that could explain some of the difference with other's experiences.)
If you wish to explain the differences between film TTL and the digital TTL technologies, it might be more appropriate in a new and seperate thread, but I'd love any insight you might provide.:thumb
Thanks for your comments,
ziggy53
Charla
Dec-17-2006, 08:26 PM
Elaine - I've been following all your technique threads and I think you've been asking a lot of great questions and I've been learning so much, so I figure it's time for me to chime in.
I also use the KM5D and have been playing a lot with diffusing and bouncing the 3600HS(d) external flash. I haven't found that it decreases with "blinkers" at all since it's a much more powerful flash. Most people need a few seconds to recover from taking a direct hit with that sucker!
I do really like the wireless feature that this flash offers. You can set it anywhere in the room pointing any direction and bounce til your hearts content :D The on camera flash still fires since it controls the wireless flash (I haven't figured out yet if it's possible to completely suppress the on camera flash) so you still get a nice fill.
I did a few shots today with this setup and found that it still takes a bit of conscious effort to keep from blinking, but it's not too horrible. Examples are posted here http://www.dgrin.com/showthread.php?t=49540 I'm still playing around with flash (wishing I had a light kit!) but I was pretty happy with these.
Keep up the good work and keep asking questions! :D
TOF guy
Dec-18-2006, 08:38 PM
With respect for your views, the only recent dSLR which seems to have a large anecdotal problem with "blinkers" is the Nikon D70.
And the Nikon D70s, the Nikon D50, and the Nikon D40 (among Nikon cameras - I'll comment on Canon later). As I've stated in my previous, I know much less about other makes ... but I know a few very very very knowledeable sources. I've noticed that the O/P has a Minolta 5D, so I've checked:
The Minolta 5D is another dSLR which by design will give you blinkers, both with internal and external flashes
That particular model seems to have a different method of preflash than other Nikon digital SLR cameras
No it doesn't: all Nkon dSLR introduced after the Nikon D70 (including the D70 itself) use the very same method of preflash.
and many people comment they can "see" a visible delay from preflash to flash. I haven't noticed it with my father's D70, so I'm not sure.
The delay is exactly 115ms from preflash to flash on the Nikon D70 (that is unless you've using rear-curtain - of course - or flash commander mode). Pretty hard to see as they're close together. But that's irrelevant. Blinking in this context is a defense mechanism when the eye is exposed to a burst of light, and has been the subject of a number of studies, including one by Kodak some 25 years ago that's now a "classic". The reaction time between the burst of light and the time a person starts closing the eye depends on each individual. A fast blinker needs 100 to 110 ms to move the eyelid (that is move enough that it becomes noticeable on a picture). Since these studies have been made, the rules of how to design a flash system that prevents blinking are well-known and verified over and over:
Pre-flash to flah less than 100 ms: no issue (example: the Nikon D80 with 80 ms lag - just fast enough, the original Canon Rebel and its immediate successor Rebel 350D/XT with 70 ms lag. I can check the number for a 1DMK II because I know of a few sources who - unlike you - know these cameras inside out, and I really mean inside out, but I can guarantee you that such a camera - a high end pro body - is way up there, certainly less than 50 ms).
Pre-flash to flash more than 100 ms: issues. A "slow" blinker needs a little less than 150ms to react. As the pre-flash to flash duration is increased, problems become more frequent. After 150 ms it doesn't matter.
Okay, back to the O/P's camera: The Minolta 5D has a lag time of 140 ms between pre-flash and flash. That's your answer.
As I mention above, "Auto" flashes don't have the same problem, and neither do manual flashes (or manual mode), as you agree. So there "are" differences in flashes, because of their technology and features, and an external flash "can" influence the quantity of blinker-less images as a result.
I've already clarified what is the critical issue with flash to prevent blinking: the pre-flash to flash duration. At this point one could argue that a better flash may help: is it possible that a better flash can shorten the lag, and reduce blinking issues?
The anwer is "no". You can put a Nkon SB600, SB800, a Sigma EF 500 DG Super if that pleases you, or any of the Metz high-end flashes on a Nikon D70, D50, or D40, and you'll get blinking issues. Attach any of the above on a D200 or D2Xs, and you'll never have an issue.
Why? You've stated yourself that the lag between pre-flash and flash may be shorter with a better flash -and that seems seems plain common sense - but as it turns out, the main bottleneck comes from the body, and for reasons that I won't get into. it gets much worse on a dSLR than on a SLR. To improve that lag, manufacturers (that is at least Canon and Nikon due to the way they've designed e-TTL II / iTTL) have to put better mechanical parts (and precision mechanical parts means $$$, as opposed to electronical parts, which cost zip) in their bodies.
You may have meant to say that there is no difference when using an E-TTL (or i-TTL as it applies) based flash, one model flash versus another. In that case I would probably agree.
Correction: E-TTL II vs. i-TTL. If you knew how often Japenese manufacturers copy one each other ...
For what it's worth, I have not detected any serious problems (or differences) using either the Canon dRebel XT/350D or the Canon 1D MKII, as relates to people blinking.
Okay, time to talk about Canon. Unlike Nikon, Canon deserves kudos for having right off the bat designed the consumer-oriented Rebel with an efficient black-out time to prevent blinking :clap . Canon has continued this honorable tradition with the Rebel XT :thumb . I didn't ask about the Xti.
(Then again, I almost always use some sort of flash technique other than direct, so that could explain some of the difference with other's experiences.)
We're in total agreement: with an external flash, the O/P can re-orient the head and bounce the flash, mount the flash off-center on a bracket, trigger the flash at a distance, and/or attach a diffuser to the head. All of these techniques will reduce the chances of a blink, and improve the image quality in many other ways...
If you wish to explain the differences between film TTL and the digital TTL technologies, it might be more appropriate in a new and seperate thread, but I'd love any insight you might provide.:thumb
This was long enough to type. Some other time, as I'm sure the subject will come back.
Thanks for your comments,
ziggy53
You're welcome. No offense, but I'm very lucky to have some very knowledgeable sources of info. You can trust the info above ...
Shay Stephens
Dec-19-2006, 10:49 PM
I don't use preflash or redeye settings, just a single flash, and I take multiple photos. That usually takes care of even the most rabid blinker ;-)
ziggy53
Dec-20-2006, 06:48 AM
I don't use preflash or redeye settings, just a single flash, and I take multiple photos. That usually takes care of even the most rabid blinker ;-)
Shay,
Exactly right. Neither "auto" flashes nor "manual" flashes have "preflash" and effectively eliminate that particular cause of reflex eye blink, regardless of camera.
ziggy53
ziggy53
Dec-20-2006, 07:16 AM
In the last couple of weeks, I've run into a few people who have struggled to keep their eyes open with my internal flash. This made for some frustrating situations when a group shot was being taken and one person always had their eyes closed or at half mast. I know some people have this tendency more than others, and I believe that some flashes cause this more than others. Is this correct? Also, when I do get my external flash, will this issue cease to be a problem or will I just have to wait and see? Does anyone have experience with this?
Thanks in advance!
Elaine
Elaine,
There appears to be a person on DPReview, "Videoguy", who uses a Minolta 5D and has experienced similar problems:
http://www.google.com/search?hl=en&lr=&safe=off&q=+site:forums.dpreview.com+%2BVideoguy+%2Bpreflash
You might check out his suggestions and comments.
ziggy53
Elaine
Dec-20-2006, 09:40 AM
Elaine,
There appears to be a person on DPReview, "Videoguy", who uses a Minolta 5D and has experienced similar problems:
http://www.google.com/search?hl=en&lr=&safe=off&q=+site:forums.dpreview.com+%2BVideoguy+%2Bpreflash
You might check out his suggestions and comments.
ziggy53
Thanks for the link, Ziggy!
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