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Thread: Newbie flash help

  1. #1

    Default Newbie flash help

    Hi! Using a camera with fixed 1/60 shutter speed when using built-in flash to optically trigger a slave flash.
    It will work from 1/128 to 1/4 but starting from 1/2 to 1, nothing is captured.

    Can someone explain what's wrong?

  2. #2
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    Default Re: Newbie flash help

    Perhaps you could try(as an experiment)setting shutter speed at 1/30 and see if 1/2 to 1 works.
    (change your camera's flash syn menu accordingly too)
    Canon | Oly | Fuji

  3. #3

    Default Re: Newbie flash help

    Quote Originally Posted by smoob View Post
    Hi! Using a camera with fixed 1/60 shutter speed when using built-in flash to optically trigger a slave flash.
    It will work from 1/128 to 1/4 but starting from 1/2 to 1, nothing is captured.

    Can someone explain what's wrong?
    "Nothing is captured" - A bit ambiguous to me. Can clarify what you mean? You hit the shutter button, the slave flash was triggered, but the captured image is all white or all dark? Can share your test images at 1/128, 1/4, 1/2 and 1?

  4. #4

    Default Re: Newbie flash help

    Quote Originally Posted by v0857 View Post
    Perhaps you could try(as an experiment)setting shutter speed at 1/30 and see if 1/2 to 1 works.
    (change your camera's flash syn menu accordingly too)
    Shutter seems to be fixed 1/60 in aperture priority and MANUAL with popup flash on. With pop up flash off, it's possible to reach 1/16000.

    Quote Originally Posted by kandinsky View Post
    "Nothing is captured" - A bit ambiguous to me. Can clarify what you mean? You hit the shutter button, the slave flash was triggered, but the captured image is all white or all dark? Can share your test images at 1/128, 1/4, 1/2 and 1?
    I'll upload later.

  5. #5

  6. #6
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    Default Re: Newbie flash help

    Quote Originally Posted by smoob View Post
    Shutter seems to be fixed 1/60 in aperture priority and MANUAL with popup flash on. With pop up flash off, it's possible to reach 1/16000.
    your issue is not with flash off. Try shutter speed of 1/30 or even lower to see if 1/2 and 1 power works. Set your camera's flash syn to auto, if it isn't.

    Quote Originally Posted by smoob View Post
    Looks like the flash didn't fire during the shutter opening time. Try a lower shutter speed to see if it does(1/30 or even lower, experiment)
    Last edited by v0857; 13th September 2017 at 08:14 PM.
    Canon | Oly | Fuji

  7. #7

    Default Re: Newbie flash help

    top image shows flash mode for all pics here, bottom shows yongnuo(1/2 power) in s1.



    top image shows yongnuo off, nikon seems to be on ttl. bottom shows yongnuo(1/2 power) firing in s2 mode, but nikon doesnt always capture.



    imaging.nikon.com/lineup/acil/bodies/j2/spec.htm

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    Default Re: Newbie flash help

    Quote Originally Posted by smoob View Post
    top image shows flash mode for all pics here, bottom shows yongnuo(1/2 power) in s1.



    top image shows yongnuo off, nikon seems to be on ttl. bottom shows yongnuo(1/2 power) firing in s2 mode, but nikon doesnt always capture.



    imaging.nikon.com/lineup/acil/bodies/j2/spec.htm
    I'm not understanding your post here. It looks like you're saying there's 4 pics, but I only see 2 pics.
    Jumping between S1 and S2 throws my focus off, in that are you doing manual and then TTL(typical uses of S1 n S2).

    I doubt I can help you further, as I'm getting a headache trying to decihper.

    Before I leave let me say this, since you want to know why your camera cannot capture the flash at 1/2 and full power, do the test in maunal mode to force the output.
    Also on your camera menu , Nikon has a commander mode, make the appropiate selection, likewise on your Yongnuo.( I'm not a Nikon user I can't take you thru the settings for commander mode, ask a friend who uses Nikon). You may have done this already, but I thought I mentioned in case it wasn't.

    I hope you'll find the answer, or perhaps another clubsnap member can better advise you.

    Sorry I can't help you out on this.
    Canon | Oly | Fuji

  9. #9
    Senior Member shierwin's Avatar
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    Default Re: Newbie flash help

    How to use flash and how to trigger a slave should be found in the body manual or in the flash manual...

  10. #10

    Default Re: Newbie flash help

    Quote Originally Posted by smoob View Post
    top image shows flash mode for all pics here, bottom shows yongnuo(1/2 power) in s1.


    top image shows yongnuo off, nikon seems to be on ttl. bottom shows yongnuo(1/2 power) firing in s2 mode, but nikon doesnt always capture.


    imaging.nikon.com/lineup/acil/bodies/j2/spec.htm
    I think you are not using the usual flash terms so everyone is getting confused with your explanations.

    I'll try to understand your question by making some assumptions:
    1. You're using Nikon J2's built in flash (probably in TTL metering mode, from J2's manual I don't see any option to set the flash power manually nor can it act as commander) as trigger
    2. You're using one of Yongnuo's manual flashes as an 'optical slave', meaning it will flash when it detects another flash going off, and you can set the flash power manually

    When a camera is using flash in TTL metering mode, what happens it will fire a pre-flash and the camera will use it to make a calculation of the flash power required, then pass the information to the flash then it will fire the actual flash at the power required. This happens in a split second so it probably only looks like the flash went off once.

    Yongnuo flash's optical sensor can detect both flashes. In S1 mode, it will flash when it first detects a flash, which is the pre-flash, and is not what you want. In S2 mode, it will ignore the pre-flash and flash together with the actual flash of the camera, which is probably what you want. Thus in the above you can see in S1 mode the Yongnuo flashed too early and it's not captured by the camera. When in S2 mode the Yongnuo flash is too powerful so the whole image is blown.


    Quote Originally Posted by smoob View Post
    Hi! Using a camera with fixed 1/60 shutter speed when using built-in flash to optically trigger a slave flash.
    It will work from 1/128 to 1/4 but starting from 1/2 to 1, nothing is captured.

    Can someone explain what's wrong?
    'Nothing is captured', as others have pointed out is not clear. If the whole image is white / blown, that means the flash has fired but the power is too great so everything is overexposed. Just lower the flash power to your desired setting.

    If the whole image is black, that means either the flash did not go off, so problem with the triggering or flash has not charged yet, or the flash did go off but not captured during the camera's exposure.


    If you're not familiar with using flash, I'll suggest you take it step by step to see how the flashes work:
    1. Set up your props, and set your camera on a tripod to minimize variables
    2. Take the photo without flash first. Set camera to manual exposure mode, dial in the settings. I'll suggest something a bit more underexposed so the flash effect is more obvious, eg 1/60s, f4, ISO800. The box you shot should be dimly lit, if not adjust the ISO accordingly.
    3. Now take another shot with your camera's flash, with the same exposure settings as above. Now the box should be brightly lit. So you know the brightly lit box is mainly due to your camera's flash. You can now play with your camera flash's flash compensation (Shooting Menu > Flash Compensation) to determine how bright the box should be. You should not change your camera's exposure settings (keep it at 1/60s, f4, ISO800 if you didn't adjust it from the step above)
    4. Now set your flash compensation to a very low number, like -2 or -3 stops, so that now the box is dimly lit again so we can see the effect of the Yongnuo flash more obviously.
    5. Turn on your Yongnuo flash, set to S2 mode, power maybe 1/32 and take a shot. Now how bright the box is lit will be mainly determined by the Yongnuo flash. If it is too bright then lower the power, or dial down the ISO or Aperture of your camera. Change only 1 variable at a time to see the effect. Make sure the Yongnuo flash has enough time to recycle it's power so it can flash with the camera's exposure. If it is still flashing but not captured by the camera then maybe change to S1 mode, I may be referencing a different Yongnuo flash mode and the modes are switched.

    Hopefully with this experiment you can understand the effects of the different settings. Then probably read up more from books or online (eg strobist.com) and practice so that you will be familiar. Hope this helps
    Last edited by thoongeng; 15th September 2017 at 01:00 AM. Reason: typo

  11. #11
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    Default Re: Newbie flash help

    Quote Originally Posted by thoongeng View Post
    I think you are not using the ....
    Exemplary effort! Very well detailed steps and guide for TS. You are truly an asset to this forum!
    Canon | Oly | Fuji

  12. #12

    Default Re: Newbie flash help

    Quote Originally Posted by smoob View Post
    ...but nikon doesnt always capture.
    In a way, when using 3rd party equipment, that's not unusual. I use YN flashes with the built in radio triggers. It's safe to say there are definitely times when a flash might not trigger. You are using 3rd party equipment that's not designed to work 100% perfectly with your nikon. Sometimes even same brand family also can't guarantee 100% because of variables that can't be controlled, like environment... You're also pushing the J2 beyond what it was designed for. The flash does not have much manual control e.g. it doesn't give you the option to switch off ttl flash, so all these factors combined, there's always the likelihood that something doesn't work as expected. In this case, maybe despite the s2 mode, the yongnuo flash, somehow at 1/2 and 1 power, is being triggered by your J2's ttl preflash? *shrug*

    I think you may have to accept that's a limitation with the two pieces of hardware you are using together.

  13. #13

    Default Re: Newbie flash help

    Quote Originally Posted by v0857 View Post
    Exemplary effort! Very well detailed steps and guide for TS. You are truly an asset to this forum!
    Thanks ah, you flatter me la heh... I only sharing the principles I remember, haven't played with flash for some time a bit rusty still need to google a bit to refresh my memory
    And still not too sure if we helped TS... I may just be making the wrong assumptions and talking rubbish hehe... just hope I can spark some discussion and the real pros will give their input

    As mod kandinsky pointed out, the Yongnuo flash may not even be compatible... maybe Nikon J2's TTL mode is a bit different and Yongnuo got confused by it...
    learnt it the hard way some time ago when I did not do my homework, bought a cheap radio trigger, supposed to work with any flash, however it just didn't work with the flash I have

  14. #14

    Default Re: Newbie flash help

    Quote Originally Posted by v0857 View Post
    I'm not understanding your post here. It looks like you're saying there's 4 pics, but I only see 2 pics.
    It's 4 pics edited into 2 to save upload time.
    Quote Originally Posted by v0857 View Post
    Jumping between S1 and S2 throws my focus off, in that are you doing manual and then TTL(typical uses of S1 n S2).

    I doubt I can help you further, as I'm getting a headache trying to decihper.
    Yes Sir, I'm getting a headache too, sometimes the flash works, sometimes it doesn't...
    Quote Originally Posted by v0857 View Post
    Before I leave let me say this, since you want to know why your camera cannot capture the flash at 1/2 and full power, do the test in maunal mode to force the output.
    Also on your camera menu , Nikon has a commander mode, make the appropiate selection, likewise on your Yongnuo.( I'm not a Nikon user I can't take you thru the settings for commander mode, ask a friend who uses Nikon). You may have done this already, but I thought I mentioned in case it wasn't.

    I hope you'll find the answer, or perhaps another clubsnap member can better advise you.
    Sorry I can't help you out on this.
    Thanks for the advise anyway.

    Quote Originally Posted by shierwin View Post
    How to use flash and how to trigger a slave should be found in the body manual or in the flash manual...

  15. #15

    Default Re: Newbie flash help

    I'm not a pro but to be honest it's quite challenging to try to use on camera pop up flash to trigger a slave via it's optical sensor (line of sight) which is normally located at the front of the flash body.As stated in Yongnuo flash manual you have to turn the flash head but actually it's the body to face the pop up flash angle of coverage which practically mean that slave must be in front of the pop up flash but looking at the photos which are closeups of the box even with pop up flash may be too near for full flash coverage reason being there is a minimum distance or the flash light can't cover because it's on top of the camera and lens barrel obstruction.At the very least the slave will be firing from the somewhere above the subject.

    Imagine if the camera and slave flash is side by side with both sensor and flash facing the front in parallel of the subject what are the chances of the slave detecting the pop up flash, even taking into account the flash light bouncing off the walls to reach the slave?

    Another thing I noticed is the ISO at 3200, most probably camera is at auto program and auto ISo 100 - 3200.Ts should take control and use ISO 100 or 200 as 3200 is very grainy for such a small image sensor.

    The thing about Yongnuo manual flashes is that although it has an "exposure" table in the user manual in the form of focal length and distance which is a far cry from the manual flashes of the film days that have a table at the back of the flash with distance and F-stop vs ISO.Yongnuo's table only give distance,focal length and ISO 100 only which is not intuitive so technically Yongnuo does not compute the F-stop for user as a starting point so unless a newbie knows how to calculate the F-stop by the flash guide number and distance to subject then these manual flashes are mostly used by "experts".Of course Yongnuo expects user to play with the power settings but if user does not know how the f-stop is calculated and the relationship of subject distace vis-a vis the lighting power ratio and f-stop they would be clueless and invariably sell their manual flash later on to buy a auto ,TTL flash which I would recommend to newbies at least they would have good exposure from the get go. Yongnuo is not doing itself a favour in terms of user friendlyness.

  16. #16

    Default Re: Newbie flash help

    Quote Originally Posted by thoongeng View Post
    I think you are not using the usual flash terms so everyone is getting confused with your explanations.

    I'll try to understand your question by making some assumptions:
    1. You're using Nikon J2's built in flash (probably in TTL metering mode, from J2's manual I don't see any option to set the flash power manually nor can it act as commander) as trigger
    2. You're using one of Yongnuo's manual flashes as an 'optical slave', meaning it will flash when it detects another flash going off, and you can set the flash power manually

    When a camera is using flash in TTL metering mode, what happens it will fire a pre-flash and the camera will use it to make a calculation of the flash power required, then pass the information to the flash then it will fire the actual flash at the power required. This happens in a split second so it probably only looks like the flash went off once.

    Yongnuo flash's optical sensor can detect both flashes. In S1 mode, it will flash when it first detects a flash, which is the pre-flash, and is not what you want. In S2 mode, it will ignore the pre-flash and flash together with the actual flash of the camera, which is probably what you want. Thus in the above you can see in S1 mode the Yongnuo flashed too early and it's not captured by the camera. When in S2 mode the Yongnuo flash is too powerful so the whole image is blown.




    'Nothing is captured', as others have pointed out is not clear. If the whole image is white / blown, that means the flash has fired but the power is too great so everything is overexposed. Just lower the flash power to your desired setting.

    If the whole image is black, that means either the flash did not go off, so problem with the triggering or flash has not charged yet, or the flash did go off but not captured during the camera's exposure.


    If you're not familiar with using flash, I'll suggest you take it step by step to see how the flashes work:
    1. Set up your props, and set your camera on a tripod to minimize variables
    2. Take the photo without flash first. Set camera to manual exposure mode, dial in the settings. I'll suggest something a bit more underexposed so the flash effect is more obvious, eg 1/60s, f4, ISO800. The box you shot should be dimly lit, if not adjust the ISO accordingly.
    3. Now take another shot with your camera's flash, with the same exposure settings as above. Now the box should be brightly lit. So you know the brightly lit box is mainly due to your camera's flash. You can now play with your camera flash's flash compensation (Shooting Menu > Flash Compensation) to determine how bright the box should be. You should not change your camera's exposure settings (keep it at 1/60s, f4, ISO800 if you didn't adjust it from the step above)
    4. Now set your flash compensation to a very low number, like -2 or -3 stops, so that now the box is dimly lit again so we can see the effect of the Yongnuo flash more obviously.
    5. Turn on your Yongnuo flash, set to S2 mode, power maybe 1/32 and take a shot. Now how bright the box is lit will be mainly determined by the Yongnuo flash. If it is too bright then lower the power, or dial down the ISO or Aperture of your camera. Change only 1 variable at a time to see the effect. Make sure the Yongnuo flash has enough time to recycle it's power so it can flash with the camera's exposure. If it is still flashing but not captured by the camera then maybe change to S1 mode, I may be referencing a different Yongnuo flash mode and the modes are switched.

    Hopefully with this experiment you can understand the effects of the different settings. Then probably read up more from books or online (eg strobist.com) and practice so that you will be familiar. Hope this helps

    https://image.ibb.co/dQRPow/a.jpg

    https://image.ibb.co/gd1crG/b.jpg

    https://image.ibb.co/guxYWG/3.jpg
    YN flash S1 mode works from 1/128 till 1/4 power. 1/2 and 1/1 produces a pop sound.
    YN flash S2 mode seems to work now. I may have blocked the built-in flash earlier.

    Quote Originally Posted by kandinsky View Post
    In a way, when using 3rd party equipment, that's not unusual. I use YN flashes with the built in radio triggers. It's safe to say there are definitely times when a flash might not trigger. You are using 3rd party equipment that's not designed to work 100% perfectly with your nikon. Sometimes even same brand family also can't guarantee 100% because of variables that can't be controlled, like environment... You're also pushing the J2 beyond what it was designed for. The flash does not have much manual control e.g. it doesn't give you the option to switch off ttl flash, so all these factors combined, there's always the likelihood that something doesn't work as expected. In this case, maybe despite the s2 mode, the yongnuo flash, somehow at 1/2 and 1 power, is being triggered by your J2's ttl preflash? *shrug*

    I think you may have to accept that's a limitation with the two pieces of hardware you are using together.
    I was using a paper to block the built-in flash and may have prevented the YN flash from functioning properly.
    Last edited by smoob; 3rd October 2017 at 12:31 AM.

  17. #17

    Default Re: Newbie flash help

    Quote Originally Posted by one eye jack View Post
    Another thing I noticed is the ISO at 3200, most probably camera is at auto program and auto ISo 100 - 3200.Ts should take control and use ISO 100 or 200 as 3200 is very grainy for such a small image sensor.
    Test images to gpgt here no need so serious and bother about iso

    Quote Originally Posted by one eye jack View Post
    The thing about Yongnuo manual flashes is that although it has an "exposure" table in the user manual in the form of focal length and distance which is a far cry from the manual flashes of the film days that have a table at the back of the flash with distance and F-stop vs ISO.Yongnuo's table only give distance,focal length and ISO 100 only which is not intuitive so technically Yongnuo does not compute the F-stop for user as a starting point so unless a newbie knows how to calculate the F-stop by the flash guide number and distance to subject then these manual flashes are mostly used by "experts".Of course Yongnuo expects user to play with the power settings but if user does not know how the f-stop is calculated and the relationship of subject distace vis-a vis the lighting power ratio and f-stop they would be clueless and invariably sell their manual flash later on to buy a auto ,TTL flash which I would recommend to newbies at least they would have good exposure from the get go. Yongnuo is not doing itself a favour in terms of user friendlyness.
    Ok more to research on. Thanks for all the replies.
    Last edited by smoob; 3rd October 2017 at 12:30 AM.

  18. #18

    Default Re: Newbie flash help

    Here's what I think of your latest series of photos of post#16:

    1. You need to know the minimum working distance of the external and built-in
    flash.Reason being the flash's angle of coverage and the power/gn (guide number). If your subject is too near the camera or under the minimum working distance the output of the flash is too powerful or bright for the minimum
    aperture setting of F22.

    2. Pics 1-4 show over exposure judging from histogram.You can see at the right side a blip at the extreme right corner and it progresses to go left
    towards the darker side.

    3. Pics 5-6, did yongnuo flash fire or not? TS said S2 worked? If so why is it under exposed this time when still at the same camera settings?

    4. As I said in my post that yongnuo manual flash is not intuitive.It does not have a table of exposure settings that tell what aperture/ISo for subject distance.

    5. For your next test and judging from using ISO 800 which is too fast/sensitive because of too near subject distance even at F22 resulting in over exposure for pop-up as well as external flash I suggest you use the lowest ISO which is ISO 100. This is where an ancient manual or auto flash from the film days will tell user for ISO 100 if subject is at minimum 1.2 meters to use F16 (but gn is more powerful than pop-up flash) or else try F11.

    6. Take note when you use manual settings you can't use flash compensation as
    it will work only with auto settings.You adjust by shutter speed and aperture with ISO.

    YN flash S1 mode works from 1/128 till 1/4 power. 1/2 and 1/1 produces a pop sound.
    YN flash S2 mode seems to work now. I may have blocked the built-in flash earlier.
    The pop sound is normal it's like a miniture lightning strike.

    EDIT: Technically you are using two flashes to light scene so 2X the power output..no wonder over expose.Also since it's on manual the pop up flash is at full power.I said before you are using bounced light from pop-up flash to trigger Yongnuo which is awkward.
    Using radio trigger is best( no need to orientate yongnuo optical sensor to try to recieve light trigger from pop-up).Whether you get the lighting effect is beside the point as the exposure is more relevant here.Worse to worse I would use semi auto like aperture/shutter speed priority and power down pop-up to lowest power or use tissue to diffuse/reduce output.
    Last edited by one eye jack; 3rd October 2017 at 11:28 AM.

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