[BigMackCam]

what you say is valid, but consider if the sun comes out unexpectedly and ruins your shot, you would say the picture is over exposed would you not, a unexpected variation in the light changed the exposure.

Yes, the picture would be over-exposed based on the amount of available light at that precise moment, because we have not adjusted our exposure settings. The captured image is not the same because of the extra light, but the exposure is the same - it's just that it is no longer appropriate to the amount of light. When we say a picture is over-exposed, what we're really saying is that it is "over-exposed based on the amount of light in front of the camera". That light may come from the sun, overhead lamps, a log fire, or... a speedlight. The amount of light isn't an exposure-related control - it's a property of the scene we're trying to capture. How we expose for it is down to shutter speed, aperture and ISO

EDIT: Interestingly, the wiki entry for exposure includes scene luminance in the overall definition of exposure, which is more in-line with your explanation. But I still think I'm right

EDIT 2: Whichever of us is actually correct, I do understand why you consider control of the light source to be part of the exposure process - it's just that I read exposure in a very literal sense... ie. exposing the sensor to whatever light is there.

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Last edited by BigMackCam; 01-31-2016 at 08:26 AM.

[Cee Cee]

You've added a p-TTL auto flash to the mix, it's no longer fully manual. A bit of info about the pre-flash is on the Ricoh website:

P-TTL pre-flash | Ricoh Imaging Support

This pre-flash is how P/I/E/?-TTL flashes from all manufacturers have worked since they were introduced afaik (this isn't the older TTL that had no pre-flashes!). You won't find every little camera nuance in the manual, there's just not enough room. And certainly not enough room to detail behavior with every expected combination of gear, like your strobes with 'dumb' optical slaves. I won't pretend the manuals are grand, but in the k-30 manual it lists the modes for the built-in flash (page 239). None of them indicate you'd have full manual controls, nor does anything under the 'flash' section of Ricoh's description of the k-30 SLR Pentax K-30 - RICOH IMAGING UK LTD.

If you want to argue that the built-in flash should have full manual controls like a user-controlled power output, then I'd fully agree. It can't be a complicated thing to include, my canon P&S from 11 years ago had a few manual flash power options. They've added this to the k3, and I hope it filters down to all future models.

For what it's worth, you can get optical slaves with a 'delay' mode for use with these fancy p-TTL type flashes. They'll sense the pre-flash then wait a smidgen before firing. A few flashes with built in slave modes include a delay option (Nikon SB-26 for example). Or you can get the cheapest hot-shoe flash with manual controls and stick it in your hotshoe. Use this to trigger your 'dumb' slaves. This would be a better option as you don't really want an on camera flash adjusting it's output and influencing the exposure, even if the off-camera strobes are syncing correctly. Another option is to get radio triggers to do the triggering and skip the optical triggers entirely.

Sorry for not understanding flash modes or even what P-TTL properly means, I consider my self just an average user, as I said I don't do much flash photography and when I do its the pop up flash in some auto mode and let the camera figure it out, or its external flash in manual mode and I play with the settings to get it right and it all behaves as expected, I don't think it's an unreasonable asumption to make that if you put the camera into manual mode that you would have full control and if you don't then the manual should say so.
I don't want to augue that the camera should have adjustable output, just that I expected that the flash would be on full the same as it is if I take the lens off the "A" setting, why would I expect this not to be the case if the manual didn't mention it.

[BrianR]

I'm going to hazard a guess that somewhere in the K-30 manual a single entry in a table states that for M lenses (or A lenses using manual aperture) P-TTL is disabled and the OBF operates at 100% power.

The table of flash features (page 239) mentions P-TTL auto on being available with "DA, DA L, D FA, FA J, FA, F or A lens", but doesn't mention what happens in other cases. There is a section on "Functions Available with Various Lens Combinations", and on page 257:

"The built-in flash cannot be regulated and fully discharges when A lenses not set to the A position, lenses manufactured prior to the A lenses or soft focus lenses are used."

Your guess was pretty good.

It's tough to write a concise manual that pleases everybody. I would have thought they could save space by not mentioning the built-in flash would vignette with the FA 600/4 or the FA 250-600/5.6, but then someone would come along and complain about the black shadow on their $7,000 lens and camera combo so you probably have to include it somewhere.

[BigMackCam]

Sorry for not understanding flash modes or even what P-TTL properly means, I consider my self just an average user, as I said I don't do much flash photography and when I do its the pop up flash in some auto mode and let the camera figure it out, or its external flash in manual mode and I play with the settings to get it right and it all behaves as expected, I don't think it's an unreasonable asumption to make that if you put the camera into manual mode that you would have full control and if you don't then the manual should say so.

I don't think it's an unreasonable assumption you've made. It just doesn't work that way - the flash system, whether in-camera or external, has to be considered as a separate system

Further to my last post, I just read a pretty good article on exposure that says what I've been saying, but in a more concise way:

"An exposure value (EV) is the total amount of light available, whereas exposure (in our cameras) is the way we use that light. "

[Cee Cee]

I've been frustrated by this for 15 years, specifically as it relates to connecting and using the myriad components of audio and video systems. The various types of cables and connections used between them, the sequence of connecting them, and the various settings possible on each individual component have various limiting effects on the next component down the line and on the system overall, but you don't know that other than by trial and error and experience. I am similarly frustrated by camera manuals - they don't tell us HOW, only WHAT.

When I read the User Guide for a camera (I read every User Guide cover-to-cover twice right after I get the camera) I'm fully aware it will not tell me HOW to use the camera to achieve an effect; it will only tell me what each button and menu setting controls. It frustrates me, but I no longer expect it. I intuitively know they're not documenting everything, because they can't do it.

As it is, the K-3 manual pushes 300 (1/2 sized) pages just to label the settings. I can't imagine how big it would be if there was a call-out for each possible combination of settings and states (OBF used vs. OBF not used, with and without slaves, for each type of lens, for instance).

There are two problems for the manual writers: levels of detail; and (assuming the logic that the level of detail should be consistently applied across the entire manual) how many levels of detail deep to go.

Think of it as a pyramid. The deeper you go, the larger the manual gets, in orders of magnitude. If they make a Call Out note for the single circumstance of remote and OB flash operating changes using the pop-up flash as a controller, using an auto lens on lens aperture control versus using an auto lens on camera aperture control, wherein P-TTL is disabled versus enabled (which I believe is a quite 'deep' level of detail) how big would the manual be if every other feature and sub-system was explained to that same level? There would be orders of magnitude more use-case call-outs than there would be straight text.

I'm going to hazard a guess that somewhere in the K-30 manual a single entry in a table states that for M lenses (or A lenses using manual aperture) P-TTL is disabled and the OBF operates at 100% power. What's missing is the connection to the effect that design limitation has on situational use of OBF with remote slave flashes. If I were writing the manual I might decide to leave that detail to the slave flash manuals (assuming the slaves are Pentax flashes). The manual writer likely believes the OBF use is fully documented at the level of detail determined suitable for the entire manual.

The frustrating thing is they can't get in each user's head and know only the use cases that interest each user. From CeeCee's perspective the call out for this use case seems at a higher level - thus worthy of a call-out in the manual - than other detailed settings are. It's frustrating, but it's an understandable omission.

I suppose we need a Herbert Keppler for the 21st century.

thanks for the input I agree with what you say. Generally I think the K30 manual is adequate, but the section relating to flash is woeful, maybe that's just because I got caught out by circumstances, some of which was my own doing. As I said earlier a few words to alert to the fact that an A lens will behave differently to a non a lens some were in the flash operation section would be benificial, when I re read the flash section after my mishap there is some reference in one of the auto flash modes refering to DA or A lens and using slower shutter speeds to increase sharpness, which to me seems clearly wrong, the slower shutter speed is used to gain more ambient background light, this was the only sugestion that a DA or A lens might behave differently, but this was an auto mode not manual. From this I had to read between the lines and think maybe the lens setting or type of lens has something to do with it, so I did some tests & confirmed my suspisions. Surely this is above and beyond what should be required to find out how your camera works.
cheers

[BigMackCam]

@monochrome - superb response, and I agree wholeheartedly

[BrianR]

... I don't think it's an unreasonable asumption to make that if you put the camera into manual mode that you would have full control and if you don't then the manual should say so.

I can't find anything misleading in the manual about the built-in flash. It certainly doesn't completely outline every possible behavior in every possible mode, but the manuals just aren't big enough to preemptively head off every single user assumption. Your assumption that it should fire at full power in "M" mode irregardless of the les was just that, an assumption, and not based on any of the literature I can see.

A better walk-away lesson is that you should test the exact same setup you plan to use during a shoot you can't re-do. Understand what went wrong and take steps to correct it for next time. I've suggested a few ways on how to overcome your syncing problems in an earlier post, if you'd like to discuss them I'd be happy to help.

I don't want to augue that the camera should have adjustable output, just that I expected that the flash would be on full the same as it is if I take the lens off the "A" setting, why would I expect this not to be the case if the manual didn't mention it.

I do, because it bloody well should! I have hope for future post k3 models

As I said earlier a few words to alert to the fact that an A lens will behave differently to a non a lens some were in the flash operation section would be benificial,

It's in the "Lens Compatibility" section but also page 66 of the k30 manual ("Using the Built-in Flash" section):

"The built-in flash always fully discharges when using a lens without an A (Auto) position"

A hint that all is not the same with non-A lenses.

[Cee Cee]

Yes, the picture would be over-exposed based on the amount of available light at that precise moment, because we have not adjusted our exposure settings. The captured image is not the same because of the extra light, but the exposure is the same - it's just that it is no longer appropriate to the amount of light. When we say a picture is over-exposed, what we're really saying is that it is "over-exposed based on the amount of light in front of the camera". That light may come from the sun, overhead lamps, a log fire, or... a speedlight. The amount of light isn't an exposure-related control - it's a property of the scene we're trying to capture. How we expose for it is down to shutter speed, aperture and ISO

EDIT: Interestingly, the wiki entry for exposure includes scene luminance in the overall definition of exposure, which is more in-line with your explanation. But I still think I'm right

EDIT 2: Whichever of us is actually correct, I do understand why you consider control of the light source to be part of the exposure process - it's just that I read exposure in a very literal sense... ie. exposing the sensor to whatever light is there.

that's what your actually saying, what I'm actually saying is the picture is over exposed no matter what the reason, my eyes and the histogram tell me its over exposed, I don't know that it matters whether it's over exposed because the ambient light changed or the wrong shutter speed or the wrong aperture is used, overexposed is overexposed isn't it.
cheers
really am going to bed now 3.29 am in Melbourne

---------- Post added 02-01-16 at 03:31 AM ----------

It's in the "Lens Compatibility" section but also page 66 of the k30 manual ("Using the Built-in Flash" section): "The built-in flash always fully discharges when using a lens without an A (Auto) position" A hint that all is not the same with non-A lenses.

arh... A description by omission, that's no way to write a manual

[BrianR]

arh... A description by omission, that's no way to write a manual

You just complained that there was no indication that an A lens would behave differently from a non A lens. Complain about the manual all you like, but for goodness sake you should at least read the thing carefully first.

[Cee Cee]

so everyone thinks I'm wrong on this ? crap manuals that don't explain the operation of your camera is the norm and we should just except it and rely on 3rd party publications, forums, our own testing & guesswork to explain how it really works.
ok. I'm done !

---------- Post added 02-01-16 at 03:49 AM ----------

You just complained that there was no indication that an A lens would behave differently from a non A lens. Complain about the manual all you like, but for goodness sake you should at least read the thing carefully first.

not quite done,
correct me if I'm wrong, didn't you say the manual refered to how a non A lens would behave, ie. firing the flash at full intensiy . therefore it implies that a "A" lens would behave differently, but it doesn't say how the A lens would behave - like I said operation explained/suggested by omission, what am I supposed to have a crystal ball.

[BigMackCam]

overexposed is overexposed isn't it.
cheers
really am going to bed now 3.29 am in Melbourne

It certainly is. No room for discussion on that one

Sleep well

---------- Post added 01-31-2016 at 04:57 PM ----------

so everyone thinks I'm wrong on this ? crap manuals that don't explain the operation of your camera is the norm and we should just except it and rely on 3rd party publications, forums, our own testing & guesswork to explain how it really works.

I think regarding the manuals, you have every right to expect better than manufacturers provide us with. I wish they were better too, but, sadly, I think we can expect to be disappointed with future manuals from Pentax or any other manufacturer. The cameras are only going to become more feature rich, and the documentation will likely skim the surface with even less detail. Frustrating, isn't it?

[BrianR]

not quite done,
correct me if I'm wrong, didn't you say the manual refered to how a non A lens would behave, ie. firing the flash at full intensiy . therefore it implies that a "A" lens would behave differently, but it doesn't say how the A lens would behave - like I said operation explained/suggested by omission, what am I supposed to have a crystal ball.

It doesn't explicitly say how an A lens will behave on that page, but it certainly should tell you that A and non A lenses behave differently with the built-in flash, which you said it didn't. That they are different is in a few other places as well, chart on page 239, the chart on page 255, the text on page 257, etc.

The chart on page 239 lists the flash functions with the Built-in flash. "P-TTL auto flash" is listed, but a manual flash mode is not. Nor is a multi-strobing effect. Nor is producing a coffee, I'm not going to be mad if it ignores my requests for a double double.

This "Full Power" with non-A lenses is an exception to the "P-TTL auto flash" behavior, and it was your assumption that it would carry over to M mode with any lens. An assumption based on what you want the camera's M mode to mean for the built-in P-TTL auto flash, not based on anything in the manual I can see. It's unfortunate you carried this assumption into a photo shoot and ran into problems, and I do understand your frustration from this, but that doesn't make it any less of a user error.

I'm done with the griping about the manual train of thought. If you have any interest in figuring out how to reliably trigger your off-camera strobes, I'm still happy to provide whatever help I can.

[Cee Cee]

It doesn't explicitly say how an A lens will behave on that page, but it certainly should tell you that A and non A lenses behave differently with the built-in flash, which you said it didn't. That they are different is in a few other places as well, chart on page 239, the chart on page 255, the text on page 257, etc.

The chart on page 239 lists the flash functions with the Built-in flash. "P-TTL auto flash" is listed, but a manual flash mode is not. Nor is a multi-strobing effect. Nor is producing a coffee, I'm not going to be mad if it ignores my requests for a double double.

This "Full Power" with non-A lenses is an exception to the "P-TTL auto flash" behavior, and it was your assumption that it would carry over to M mode with any lens. An assumption based on what you want the camera's M mode to mean for the built-in P-TTL auto flash, not based on anything in the manual I can see. It's unfortunate you carried this assumption into a photo shoot and ran into problems, and I do understand your frustration from this, but that doesn't make it any less of a user error.

I'm done with the griping about the manual train of thought. If you have any interest in figuring out how to reliably trigger your off-camera strobes, I'm still happy to provide whatever help I can.

thanks for the offer but now that I know how the problem came about its no longer a problem, just use the aperture ring to set the aperture and all is good,. this is what I did the previous year and was very happy with the results. I've also fitted hard wire trigger inputs on the strobes so I have the option to trigger the strobes directly via a wired connection from the hotshoe, no need to use the onboard flash at all, another alternative for optical trigger is to use an external manual flash, which rather frustratingly I had intended to do, using some bounch flash off the white ceiling to trigger the stobes but decided on the night that I would get sick of rotating the flash head toward the ceiling every time I changed camera orientation, If I had of stuck with that plan there would have been no issues. Unfortunately the thought that the camera would behave in some unexpected manor never entered my head, I'd set the camera to manual after all. As I said I'm not an experienced user of flash, its not something I do a lot, and its usually on one of the auto modes and I let the camera have its way.
cheers

Edit: just one final thought on manuals, what we get with the camera is more a user guide rather than a full technical operations manual, I really think Pentax should at least publish a full operating manual as a PDF so that on those occasions when you need get down to the deeper operation aspects the info would at least be there to view on line or download and not have to use a 3rd party to find info on how it works. Much of the equipment I work on take such an approach, and just distribute a quick start guide or user guide with the full manual available on line as a PDF

[BigMackCam]

thanks for the offer but now that I know how the problem came about its no longer a problem, just use the aperture ring to set the aperture and all is good,. this is what I did the previous year and was very happy with the results. I've also fitted hard wire trigger inputs on the strobes so I have the option to trigger the strobes directly via a wired connection from the hotshoe, no need to use the onboard flash at all, another alternative for optical trigger is to use an external manual flash, which rather frustratingly I had intended to do, using some bounch flash off the white ceiling to trigger the stobes but decided on the night that I would get sick of rotating the flash head toward the ceiling every time I changed camera orientation, If I had of stuck with that plan there would have been no issues. Unfortunately the thought that the camera would behave in some unexpected manor never entered my head, I'd set the camera to manual after all. As I said I'm not an experienced user of flash, its not something I do a lot, and its usually on one of the auto modes and I let the camera have its way.
cheers

Did you sleep?!?

And for what it's worth, what you just talked through didn't sound so inexperienced - I think you're doing just fine

[Cee Cee]

Did you sleep?!?

And for what it's worth, what you just talked through didn't sound so inexperienced - I think you're doing just fine

thanks for those comments, yeah I did get some, but I have a few sleep issues anyway thankfully I'm self employed
cheers