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10-29-2015, 02:15 PM - 4 Likes   #1
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Its Time To Upgrade ....

..... your PENTAX FLASH GUIDE !


I'm really pleased to announce that the new 2nd Edition of my guide, The Pentax Digital Camera Flash Lighting System is now available right here on PentaxForums, and thanks again to Adam for supporting this project so wholeheartedly .

The new edition is downloadable from links in the new Homepage Article, the Sticky thread at the top of the Flash Forum, or right here ...

https://www.pentaxforums.com/forums/attachments/125-flashes-lighting-studio/2...edition-c-.pdf


This new version is based on the original but adds an additional 17 pages, some of the new material being based on suggestions for content made here by forum members. You will find the following improvements and updates ...


Expanded discussion of the Dedicated System Flash vs Radio Triggered Manual Systems ....

Improved P-TTL performance and compatibility information, based on extensive discussion and testing by people right here at PF ....

New images of the Pentax AF-540FGZII AW flash, plus a new section directly comparing the older and newer Pentax 'Flagship' models ....

Full coverage of the new features with the AF-360/540FGZ II AW flashes, including LED light functions, function menu and control panel ....

Expanded Wireless section adding in exploration of the wireless lighting ratio control and flash compensations....

A new look for extra clarity, and page numbers added


I've really enjoyed putting together this new edition of the guide. The first received such a great reception from members here, which made it all so worthwhile, and I hope this next step forward for the guide will prove just as useful in promoting the fun and reliable use of flash with our Pentax cameras! Please let me know what you think and keep offering the suggestions, questions and discussion about Pentax flash.

Nigel

10-29-2015, 03:01 PM   #2
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Thank you, @mcgregni. The first one was spectacular. I'm looking forward to this one.
10-29-2015, 03:06 PM   #3
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You're truly awesome, Nigel, no doubt about it.

I don't even own an accessory flash for my K-3, although I do occasionally use its pop-up flash for fill, with reasonably pleasing results when carefully dialled down. And while I love to shoot with natural, available, or ambient light, this doesn't mean that I'm not interested in flash photography. It's probably just my somewhat tight photo budget that has made me focus more on lenses and other accessories.

At any rate, the amount of expertise, skill, and passion for photography is clear from every page of your guide, and I think you're a pretty gifted writer too. And you share all this for free, just for the love of what you're doing! You remain an inspiration, and your work makes me proud to call myself a Pentaxian.

Keep this great stuff coming, Nigel, and keep on shooting!
10-29-2015, 04:31 PM   #4
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In the name of all Pentax user, THANK YOU, Nigel ! Truly outstanding !

10-29-2015, 04:40 PM   #5
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Hey, no problem, and I appreciate the kind words. I enjoy the thinking about things and writing it all down, and often when I can't get out with the camera, then the thinking and writing is the next best thing! Kath, Madaboutpix and Claudia, glad to have your support.
10-30-2015, 03:33 AM   #6
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Many thanks

Hi.

Many thanks for all your effort and hard work. Much appreciated.

Flash photography is a potential minefield even for the experienced user so your contribution has been great for all in the Pentax/Ricoh community.

Howie Be
10-30-2015, 03:35 AM   #7
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More thanks for helping us flash novices to navigate around the minefield of jargon that seems to surround the topic.

10-31-2015, 12:58 AM   #8
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Howie Be and roberri, thanks for your comments .....I love the messing around with flash and the writing about it, so I didn't FEEL like too much hard work! I hope you find some useful things in the guide there.
11-10-2015, 06:45 PM   #9
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QuoteOriginally posted by mcgregni Quote
..... your PENTAX FLASH GUIDE !


I'm really pleased to announce that the new 2nd Edition of my guide, The Pentax Digital Camera Flash Lighting System is now available right here on PentaxForums, and thanks again to Adam for supporting this project so wholeheartedly .

The new edition is downloadable from links in the new Homepage Article, the Sticky thread at the top of the Flash Forum, or right here ...

https://www.pentaxforums.com/forums/attachments/125-flashes-lighting-studio/2...edition-c-.pdf


This new version is based on the original but adds an additional 17 pages, some of the new material being based on suggestions for content made here by forum members. You will find the following improvements and updates ...


Expanded discussion of the Dedicated System Flash vs Radio Triggered Manual Systems ....

Improved P-TTL performance and compatibility information, based on extensive discussion and testing by people right here at PF ....

New images of the Pentax AF-540FGZII AW flash, plus a new section directly comparing the older and newer Pentax 'Flagship' models ....

Full coverage of the new features with the AF-360/540FGZ II AW flashes, including LED light functions, function menu and control panel ....

Expanded Wireless section adding in exploration of the wireless lighting ratio control and flash compensations....

A new look for extra clarity, and page numbers added


I've really enjoyed putting together this new edition of the guide. The first received such a great reception from members here, which made it all so worthwhile, and I hope this next step forward for the guide will prove just as useful in promoting the fun and reliable use of flash with our Pentax cameras! Please let me know what you think and keep offering the suggestions, questions and discussion about Pentax flash.

Nigel
woot woot, thanks for all the work.
11-11-2015, 07:58 AM   #10
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Thanks for the woots!

For anyone who saw the original Guide and is looking to quickly check out the new information, here is a list of the sections and pages numbers of all the new material ....

Page 7, Welcome
Pages 14-19, Dedicated System Flash & The Alternatives
Pages 20-24, The Modern Pentax Flash Units
Pages 67-72, Wireless Operations
Pages 85-88, New Features on the AF-360/540FGZII


I hope the new additions have addressed points raised after the issue of the first guide. Of course, it will keep evolving over time as things change and new equipment comes out.
11-22-2015, 12:09 PM   #11
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This sub-discussion about Pentax P-TTL Wireless Ratio Control developed on the thread “Yongnuo YN560-TX Wireless Flash Controller vs Cactus”, so rather than further clutter that thread I’ll respond here where the material is relevant to this Guide ….



QuoteOriginally posted by Class A Quote
....

In the interest of giving full advice, I'd add what you stated in another post:
"It is a normal part of the workflow to use Flash Compensation and take positive control to tell the system what you need."
So it seems that typically manual interference is required, diminishing the speed advantage over a manual approach that requires an initial honing in on the right level. This certainly has been my experience with P-TTL and the K-5 II; automatic P-TTL exposures rarely ever worked for me without manually applying compensation.

I'm wondering how you make three P-TTL flashes work for you. The lighting ratio controls (offering only 50%, 303%, and 66%) only seem to be targeted to two flashguns. Does the third, on-camera flashgun, degenerate to an oversized, heavy optical trigger when you use two off-camera flashes? I guess it could be controlled manually and be used as a subtle fill flash, but would it still control the two off-camera flashes this way?

I don't see how P-TTL can work with three flashguns that operate at different levels without requiring you to walk up to the off-camera flashes to set lighting ratios or exposure compensation manually. I tried a quick search but nothing turned up that suggested a use of lighting ratios beyond two flashguns. I always thought this apparent limitation was one of the aspects that made P-TTL outdated and I would be interested to learn whether I have been wrong with this assumption.

I asked the same question about lighting ratio control for more than two flashes in another thread where we started about talking what system-dedicated flashguns bring to the table, so it would suffice to answer the question only there. Hope to be hearing from you about this soon; would be great to either get my assumption confirmed or refuted.

P-TTL Flash Compensations
ClassA, firstly in relation to Flash Compensations with P-TTL automatic flash exposures, the difference between this process and manual setting of flash output is really about workflow approaches. There’s no sense in stacking one against the other and saying ‘this one is better because it has less steps to get to a good exposure’. That would depend on both the suitability of the situation to either automatic or manual flash modes, plus the particular skills and practices that the photographer employs.

For example, you might get a good manual exposure quickly with your Cactus setup because you have an efficient workflow to assess distances, have knowledge of the available power and make the adjustments quickly. I might get a good manual exposure quickly with my Pentax setup because I’m used to using the communication aspects between camera and flash, which provide me with instant range & distance indication, allowing me to fine tune my settings or distances and see the results update instantly.

You have made your views on P-TTL exposure reliability well known, but like any system its about working with it and getting to know it. Personally, I find there is a great logic to the mental process of seeing flash exposure in terms of ‘stops away from meter centre’. This is probably because that’s how we conceive of natural lighting exposure …. We see what the camera thinks, what it gives us as ‘meter centre’, and know intuitively from experience what compensation to apply to correct for the variations caused by surface reflectivity, or we check the LCD and histogram to make the right adjustment.



The meter for the flash exposure works the same way, so we can assess our flash exposure based on known reflectivity, and with experience we will know what to expect in certain situations. The Flash Compensations become logical and intuitive when seen on the same scale as the ambient exposure …. So we can think of, for example, ‘I want my background ambient to be 1 stop under to give deep tones, but I set my flash exposure to 0.7 stop over in order for my subject to stand out’. It is this connection to the ambient exposure and our judgements about it in relation to what the camera thinks that I am saying is the basis for Flash Compensations being an intuitive and logical part of the workflow.



An ambient exposure does not always come out perfectly first time … now you wouldn’t say that is cause to reject any automatic camera exposure modes in favour of only using manual, would you? Likewise, a P-TTL flash exposure will not always produce the exact results we’re looking for first time, an equally, that’s no reason to reject the mode outright. Its about using the logical and intuitive compensation steps to fine tune, and in fact mentally holding the details, such as ‘my flash exposure is set to 0.7 stop over’ can be helpful as a reference point to relate the flash brightness to other aspects of the scene, be it the ambient exposure or the settings on other flashes.


P-TTL ‘Wireless Lighting Ratio Control’
Frankly, we both might as well make this up as we go along! I have certainly been working fairly blind to try and lay out a description of a very useful creative tool for wireless automatic exposures, but there is really nothing documented. The useless Manuals make one tiny reference in the Wireless section, referring to ‘flash output setting’ (then listing the ratios 1/1, ½, 1/3, 2/3).

The feature is similar in concept to ‘Contrast Control Sync’, which is an extension cord function, and again there is painfully little in the manuals. It is clear enough that both ratio control features are designed to offer simple creative lighting balance control during P-TTL exposures, for 2 or 3 flashes. Of course I would not try and equate it to the complex multi-flash control possibilities of Cactus systems etc. I have tried to make that distinction in complexity terms as to which system is likely to suit which kind of photographer and situations.



The Wireless Lighting Ratio Control works beautifully for subtle and easy contrast effects with automatic exposures. The ratio set on the flashes remains a constant even while changing the ‘global’ flash exposure with FC from the camera control.

Now, ClassA, you are right in your interpretations of what I have written in the guide …. This easy and simple contrast control works well with 2 P-TTL slave flashes and 1 on-camera control flash, or 1 on-camera Master flash and 1 Slave flash, or 1 on-camera Master flash and 2 Slaves. That is what is demonstrable. Please bear in mind that my Guide is a practical workflow and best practices support document ….. it is not an attempt to create non-existent user manual materials. It is not possible for me to make up what the Pentax designers did not bother to tell anyone. I can only offer support for those aspects of the system that are clearly demonstrable, within the limits of my own equipment.


Regarding the third on-camera flash ….. consistent with the Contrast-Sync functioning, a built-in flash as master in conjunction with 1 or 2 slaves set with ratios, will emit half of the light output of the slaves. Pentax show this in the manual as ‘1:2’. So the built in will provide half of what the slaves do, and the slave/s (providing twice of what the built-in does) will provide that output with the specific ratio split as set on two flashes. (!!)



I’ll tell you where it falls down, and that is where a lot of built-in flash exposures fall down ….. when the built- in flash is too close to the subject. The minimum power limits of a guide number 13 flash unit pointed straight at a subject can be a very real problem, in any situation, not just when used combined with wireless flashes. Try using ISO 400, f4.0 at close distances and the ability of the built-in unit to provide half of the output that the slaves are providing is clearly going to be compromised. This is only going to be practical at longer distances or with diffusion on the built-in unit.

The simple approach with two off-camera slaves set to a 1/3 - 2/3 split, controlled by a built-in flash in 'Controller' mode, or a 2 flashgun approach, 1 on-camera / 1 off-camera with a 1/3 - 2/3 split, are practical and helpful solutions, and certainly those are the two configurations I use mostly. The on-camera flashgun is always bounced up and sideways with a Gary Fong Lightshere on, which gives a soft spread as well as some forwards front-fill and a little catchlight.

---------- Post added 22-11-15 at 19:29 ----------
(Originally posted in the thread ' K5 and Metz 48', moved here to avoid cluttering that thread further)

QuoteOriginally posted by Class A Quote
I finally had a chance to read through pages 14-19 of your guide you pointed me to regarding my question as to what you were referencing with your statement I quoted above.

The only features I found that are not also found with other manual solutions are:
  1. Automatic control of flash head zoom setting.
  2. Flash to subject distance indication.
  3. Flash-ready indication in the viewfinder.
Features 1. & 2. only make sense for an on-camera flash, pointing directly at the subject (i.e., not bouncing it from a reflective surface). The P-TTL flashes I've seen all disable at least 2. once you take the flash head off the "direct forward" position, which makes sense as in any other usage scenario, the distance indication would not be reliable anymore.

Disabling feature 1. would also make sense in such a scenario because when bouncing flash the ideal setting for the flash head is determined by the distances between camera - surface - subject. You don't want that setting to be automatically changed whenever changing the zoom setting of the lens.

Speaking of zoom lenses, feature 1. only makes a noteworthy difference when using a zoom lens. With a fixed focal length, one can just set the flash head zoom accordingly, sometimes deviating from what the nominal focal length would suggest. As you state yourself elsewhere in the guide, this is often useful.

IMO, this reduces the applicability of 1. & 2. to subtle fill flash since a key light from an on-camera flash will give a typically rather undesirable look. Do you agree?

Feature 3. (flash-ready indicator in the viewfinder) is nice. Many flashes support a "ready beep" as a substitute, but I personally turn it off because I find it distracting for subjects. A silent visual feedback in the viewfinder is much preferred.

Does it work for off-camera flashes as well, or is the indication for the on-camera mounted flash only?

Modern flashes recycle rather quickly though, so I don't find a ready signal to be super essential anymore, but surely it can be nice to have.

Did I miss anything?

On the negative side, in comparison to a good manual system, we seem to have:
  1. No manual control for off-camera flash units from the camera position.
  2. No individual turning on and off of flashes from the camera position.
  3. No influence on the off-camera flash power level ratios or flash compensation from the camera position.
  4. Off-camera flash heads cannot be zoomed from the camera position.
  5. All the issues with optical triggering such as limited distance, less flexibility regarding placement, reliability in less then ideal situations, introduction of shutter lag, and sometimes the issue of making sure that control flash is not seen in the image (it can sometimes be seen in reflective areas, even when the on-camera flash is set to "control" mode.)......

P.S.: I noticed a couple of inaccuracies in your guide:

You wrote that radio triggers support a range of "20-30m". I cannot think of many triggers that do not easily support 100m range or more outdoors. Some radio triggers rather have the inverse problem in that they require a minimum distance to work (say 25cm or so). This can lead to challenges when doing macro work, for instance. That's why the Cactus V6 has a "short range" option that removes this minimal distance requirement at the expense of extreme (100m+) reach. It will still support ~30m in that mode.

You state that HSS bursts "only lasts for as long as, or shorter than the time value set (1/500s / 1/1000s etc.).". That's not true. HSS bursts always have to last as long as it takes the second curtain to reach the end of its travel. That's 1/180s in the case of Pentax. So you cannot save power by increasing the shutter speed in HSS mode. On the contrary, higher shutter speeds cut down on the light received from a flash so if you want to maintain the same flash exposure, the flash needs to work harder accordingly.

Thanks for the feedback again ..... You've taking it back though to a bullet-point type of approach. I rejected this style for the Guide, as it is too simplistic to list pros and cons against one another. I have tried to write a more sweeping overview style of text, to give a feel and flavour of what each system type offers an individual. I am trying to convey the a sense of what working with the systems involves, and aiming to offer individuals a way to judge what style of working is best for them. If it comes down to a listing of features then people have to check exactly whats available on specific flashes, but I'm covering in the guide a broader picture .... some people will relate to the workflow and automated features of a Dedicated System, and others will relate to the offerings from a manual radio system.

One clarification, your point 3 above (which I have highlighted) about exposure control from the camera position ,.... when working with slave flashes in P-TTL mode, the 'global' flash exposure can be controlled from the camera with the camera Flash Compensation setting. If there is a flashgun on-camera in 'Master' mode then the 'global' flash exposure (affecting all flashes equally) will still be controlled from the camera FC setting ..... individual flash unit compensations can be set on each flash individually, and these will remain as adjustment 'splits' of the total exposure. It is true that there is no power control from the camera in manual flash mode.

I will make that correction regarding HSS flash durations in the next version of the guide ....

Regarding the range of radio transmitters, I actually wrote 'Radio triggered technology means that the range of reception can be very long, certainly over 20-30 meters distance, so suited to large spaces and outdoors' .... I read a number of different systems specifications, and that seemed a fair summary.... 20-30 meters is a very long way!

The 'Flash Ready' indication in the camera viewfinder is for on-camera flashes only. Pentax slave flashes have a red flashing light in their control panel to indicate when charged and ready, but of course this may not be visible from the camera position.

Thanks again for your detailed feedback

Last edited by mcgregni; 11-22-2015 at 01:01 PM.
11-24-2015, 05:51 AM   #12
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QuoteOriginally posted by mcgregni Quote
ClassA, firstly in relation to Flash Compensations with P-TTL automatic flash exposures, the difference between this process and manual setting of flash output is really about workflow approaches. There’s no sense in stacking one against the other and saying ‘this one is better because it has less steps to get to a good exposure’.
I see where you are coming from and I understand your viewpoint.

I work with the assumption that one should adopt one's workflow based on which system supports the most efficient and/or enjoyable approach. That's why I'm comparing system properties, because I'm assuming that someone should pick a system based on how well its properties fit with what they are trying to achieve, not based on whether the system supports a certain pre-determined workflow.

It is reasonable to assume that some people want to have a certain workflow and are not prepared to change it, even if using a different workflow based on a different system would give them better results. So I think both our styles make sense.

QuoteOriginally posted by mcgregni Quote
You have made your views on P-TTL exposure reliability well known, but like any system its about working with it and getting to know it.
Sure, I agree.

I'm happy for anyone preferring the P-TTL approach, I only respond when I feel that P-TTL is characterised as a system that very smoothly yields optimal results and that it only requires an investment into a system-dedicated approach to obtain a pain-free experience.

QuoteOriginally posted by mcgregni Quote
Personally, I find there is a great logic to the mental process of seeing flash exposure in terms of ‘stops away from meter centre’.
I can relate to that. Again, I only object to overselling the approach.

Automatic metering is always based on a 18% grey exposure and can thus be fooled by subjects with a different reflectance. Most cameras do not distinguish between a face and a black curtain next to it and hence will typically overexpose, etc. All this can be addressed but it is simply not true that we have slow manual systems on the one hand and quick and easy automated systems on the other hand.

Your enthusiasm for dedicated systems sometimes let's you write in a manner that -- at least to my eyes -- glosses over many real complications of dedicated systems. I'm sure you'll find the same applies in reverse to my posts.

QuoteOriginally posted by mcgregni Quote
An ambient exposure does not always come out perfectly first time … now you wouldn’t say that is cause to reject any automatic camera exposure modes in favour of only using manual, would you?
I certainly would not.

However, I would object to someone if they suggested that automatic camera exposure mode give quick and great results and are a simple solution that is preferable except for a few, rare situations and are a great alternative to the complex manual mode.

That would just be overselling automatic camera exposure modes and I think that automatic flash exposure is a step more complicated than automatic camera metering and hence easier to oversell.

QuoteOriginally posted by mcgregni Quote
Likewise, a P-TTL flash exposure will not always produce the exact results we’re looking for first time, an equally, that’s no reason to reject the mode outright.
Sure, I think by now it should be clear that I'm not rejecting P-TTL outright.

I just think it is fair to be explicit about the limitations of P-TTL when, e.g., advising people on a flash model decision.

QuoteOriginally posted by mcgregni Quote
Frankly, we both might as well make this up as we go along! I have certainly been working fairly blind to try and lay out a description of a very useful creative tool for wireless automatic exposures, but there is really nothing documented.
Thanks for confirming that the respective documentation is lacking.
I've read flash manuals and tried to find more information online, but there is precious little information available.

I have two P-TTL flashguns myself that I haven't used for years, but that's not enough to experiment with what happens when you try to control ratios among three flashguns.

QuoteOriginally posted by mcgregni Quote
It is clear enough that both ratio control features are designed to offer simple creative lighting balance control during P-TTL exposures, for 2 or 3 flashes.
I understand how it is supposed to work for two flashes, but how about three?

If, as you say elsewhere, the third (on-camera) flash always works with half the power of the two off-camera flashes then I wouldn't call that "light balance control", as there is no "control" over the third flash. Again, for me this is about overselling. I don't think you can tell someone that P-TTL will give them sufficient lighting control for up to three flashes when you cannot really influence what the third flash is doing. AFAIC, P-TTL appears to give one rather limited control over two flashes. That may work for a number of limited scenarios, but surely it does not give one the creative control one would need in many situations, e.g., in portrait lighting.

QuoteOriginally posted by mcgregni Quote
Of course I would not try and equate it to the complex multi-flash control possibilities of Cactus systems etc.
Why do you write "complex"?

AFAIC, this choice of words ascribes a property to manual systems, which just isn't there. What could be simpler than having explicit control over the power output of each flash?

On the contrary, I find the interaction of automatic P-TTL exposure with all sorts of camera modes complex and requiring considerable effort to understand and memorise what logic the camera uses to adjust, limit, or fix shutter speed, for instance. Or, when the camera takes a fill-light vs key light approach, etc. Your guide is a great asset to anyone interested in understanding P-TTL-based flash photography, but its size is also testament to the complexity of the system and the volume of concepts one should ideally be knowing about.

A guide for a manual system, on the other hand, can be extremely short.

QuoteOriginally posted by mcgregni Quote
The Wireless Lighting Ratio Control works beautifully for subtle and easy contrast effects with automatic exposures.
I'm not contesting that it works in some situations, but I think it is fair to say that the creative control is rather limited.

It is a bit like stating the "flower", "portrait", and "landscape" settings that existed on cheap film P&S cameras work great for many scenarios. True, they work and most people don't need more. However, we DSLR users like to have explicit control over focus and also like to be creative with our DOF choices. Likewise, I'm assuming that someone using a DLSR will eventually want to have control over the power of a rimlight in portrait lighting, or achieve a contrast ratio that is different to the canned P-TTL ones.

That's why -- at times -- I suggested that P-TTL is not a "simple system for many scenarios" but a "system that works for some simple scenarios". Again, I don't want to say P-TTL is useless, but I think it is easy to oversell it as something that it isn't.

BTW, I understand that P-TTL flashes offer individual exposure compensation, but
  1. this implies manipulating flashes individually, which can be a pain when flashes are on high light stands, or within a softbox, behind a subject, etc.
  2. Compensation is limited to -3EV -- +1EV. That is not enough in general. It will work for some situations, but just setting a level manually without limitations and the potential need to adjust the overall level at the same time is so much easier.

QuoteOriginally posted by mcgregni Quote
It is not possible for me to make up what the Pentax designers did not bother to tell anyone.
Of course not.

Please know that I did not intend to criticise you or your guide for not being more informative. I just wanted to understand whether my understanding of the limitations of P-TTL is accurate or not. It seems that I have been right in the past when I, for instance, wrote that P-TTL is inferior to Nikon's CLS and is in need of an overhaul, and that it isn't really suited for multiple light setups. OK, it provides some limited control with two lights, but personally, even if I only used two lights, I'd go manual.

QuoteOriginally posted by mcgregni Quote
You've taking it back though to a bullet-point type of approach. I rejected this style for the Guide, as it is too simplistic to list pros and cons against one another.
Well, my use of a bullet-style approach was not a suggestion that you should use the same style.

I just find it easier -- when trying to understand the differences between two approaches -- to concisely list points of difference.

QuoteOriginally posted by mcgregni Quote
One clarification, your point 3 above (which I have highlighted) about exposure control from the camera position ,.... when working with slave flashes in P-TTL mode, the 'global' flash exposure can be controlled from the camera with the camera Flash Compensation setting.
Yes, global flash exposure can be controlled from the camera, but when I wrote
"3. No influence on the off-camera flash power level ratios or flash compensation from the camera position."
I meant to refer to off-camera flash power level ratios and individual off-camera flash compensations. I can see now that my phrasing was poor.

I understand the K-3 added better control over the built-in flash, adding manual control. Have you ever checked out the K-3 manual whether the K-3 may have improved control over off-camera flashguns in any way? AFAIC, there is no good reason why the camera shouldn't support more control over off-camera flashguns.

QuoteOriginally posted by mcgregni Quote
I read a number of different systems specifications, and that seemed a fair summary.... 20-30 meters is a very long way!
I try to write my reviews in a manner that is helpful to other people even when they have different needs than I do. A reader of your guide may think "Oh shoot, I really needed 60m reach" so while you think that "20-30m is a very long way" someone else may wonder why bother if the improvement over optical triggering isn't that impressive. PocketWizard, Phottix and Cactus (V5/V6) triggers to name just a few of the top of my head for sure do 100m easily.

QuoteOriginally posted by mcgregni Quote
The 'Flash Ready' indication in the camera viewfinder is for on-camera flashes only.
Thanks for the information!

QuoteOriginally posted by mcgregni Quote
Thanks for the feedback again .....
I'm glad if it is helpful to you!
11-25-2015, 12:21 PM   #13
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Thanks again, its actually really good to have this discussion (I hope there are others reading who agree), because these issues are about more than just specific flash products and lists of features .... it is about styles and personal needs, and how the photographer looks to approach their flash working.

Firstly ClassA, we can absolutely agree that you cannot expect to just go and buy an expensive multi-functional flashgun and expect that it will sort out all your exposure and creative lighting problems. In fact, it is because of that fact that I wrote a 90 page Guide to the dedicated Pentax flash system !! So I never want to give the impression that just spending more money is the best thing for everyone to do.

Of course, I love working with my Pentax flashes and enjoy good reliable performance, and I feel that I get great value from them because of their versatility for on-camera and wireless work .... and, for me personally, I am happy to stick within the limitations of the 2-3 flash set-up that works successfully with fairly simple wireless control. So I guess I will naturally emphasise the positives and try and 'spread the word'. Is it fair to say that you also 'naturally emphasise' the positives of the Cactus system and try and 'spread the word' ..... ?

Regarding Wireless Lighting Ratio Control, I have only experiemented with 2 flashguns and one pop-up trigger unit, and in Master mode the pop-up reverts very much to a light fill-in (as it emits half the output of the 2 flashgunscombined) .... the success of this is very much dependent on having a reasonable distance between the subject and the camera as its all too easy for the distance to be too small and breach the pop-ups minimum output limit. Ihave not been able to assess how the ratio system deals with three flashguns.If anyone wants to give it a go then please let us know! As I've always said,this is an evolving information resource.

Bear in mind though that we do have full flash compensation control on any flashgun, including an on-camera one in master mode, and these settings will further add to the contrast effects in addition to and ratio settings. It is an obvious limitation though that you cannot control these things from the camera position, which is the preserve of some radio manual systems (at least for Pentax compatible flashes anyway). The K3 has not added any further control over slave flashes in any way. The only means of communication wirelessly is during the pre-flash sequence, and that is one-way communication .... the 'master' or 'controller' flash sends out mode and flash output instructions to the slaves .... the slaves and 'master' fire their metering pre-flashes and the camera reads the light ..... the camera calculates the final power needed to take account of variations measured from the pre-flash and then the master flash sends a further final optical signal passing that power information..... all flashes then fire their instructed power outputs during the exposure (there's no further adjustment).

The flash compensation limits on the older 'Mk1' Pentax flashes are -3.0 - +1.0 stops ..... the newer MkII models have extended this to -4.0 - +2.0, a total of 7 stops adjustment. The manual power settings have been extended from 1/1 through to 1/256, nine steps. Overall a clear improvement on the earlier models. The newer models allow adjustment steps to be custom set to either 1/2 stops or 1/3 stops, and it can be set to automatically follow the camera custom setting for exposure setting steps.

I'll gladly look at increasing the suggested average range I refer to in the Guide for radio manual systems ...... if '20-30' is not enough, what would you suggest is a fair average figure, considering that I'm not referring to any specific product?

Finally, it may be a good place to consider this valuable aspect of Dedicated System flash ...... the ability to divide ambient exposure into a manual operation while maintaining automatic flash exposure. Look at it like this (and again this comes down to personal workflow choices), but it can be very helpful to establish an automatic flash exposure EV (which might involve flash compensation), and allow that to be held automatically while moving the ambient exposure around it manually. Or you can make camera setting adjustments without having to re-adjust your previously established flash exposure. Any aperture, ISO or flash head zoom adjustments you make WILL NOT affect the P-TTL automatic exposure, so the flash exposure will be held even though you adjust the other things around it. You can make DOF, subject distance and flash zoom effect changes without having to re-adjust the flash exposure in response each time.

Last edited by mcgregni; 11-25-2015 at 12:33 PM.
11-25-2015, 04:57 PM   #14
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One further extension to this manual ambient with P-TTL flash exposure workflow is that once your flash exposure is set, and maybe you've established a main and fill ratio, (so you've got a nice highlight exposure and the right amount of contrast on the off-side), then you are free to move your flashes, with the modifiers on, closer to and further from the subject, in order to play creatively with the light qualities, but WITHOUT AFFECTING YOUR ESTABLISHED FLASH EXPOSURE, (which will remain constant as you set because the automatic metering system will instantly adjust to the changes in flash to subject distances. In manual mode you need to make additional compensatory power adjustments with each movement.
11-25-2015, 05:09 PM   #15
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Well done, Nigel.
This forum is a great source for help, from lots of members.
BUT you have gone the extra step.
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