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02-13-2013, 01:04 PM   #1
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TTL-issue?

Found this link about k-5.
RiceHigh's Pentax Blog: Pathetic Canon's External Auto Saves the Pathetic TTL of Pentax!

Someone know what this issue is about?, never heard of it before.

02-13-2013, 01:55 PM   #2
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A lot of people find the traditional auto thyristor flashes to be more consistent than P-TTL in some cases, the Canon 580EX II has the sensor for that. Mostly what he is talking about is the fact that the Canon remembers the setting when switched off, which may be true of many other flashes too.

Mostly it is him taking a small thing and blowing it up to be a huge deal to get views.

I don't personally use any P-TTL flash, mostly because I usually have it off camera on wireless triggers, but also because most of my lenses don't have the A contacts required for P-TTL.
02-13-2013, 02:02 PM   #3
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I you want that the EV compensation is always applied, simply do that inside the camera
02-13-2013, 02:05 PM   #4
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P-TTL and TTL are attractive, in that the camera is analyzing the light actually coming through the lens and interacting with the flash to provide the perfect exposure every time.

However....the cameras are doing this with algorithms, not with a photographer's eye. They're trying to center that histogram and expose everything optimally, which we photographers might not want. Furthermore, the cameras are frequently trying to adequately expose everything in a frame in which it is impossible to adequately expose every portion of the frame.

Even more problematic, there is frequently variation in metering between shots as light changes, if the photographer doesn't completely control the light, including providing a completely stable camera position and a completely stable subject. One shot might be great, the next underexposed or blown out. There is a lot of variability in metering. I mean, unless you are lighting inanimate objects in a studio, there are changes in ambient light, changes in camera position (even subtle ones, only the tripod holds the camera steady), changes in environment (including all reflective surfaces) and changes in subject orientation to the light as the subjects move or are rearranged. Please note that forums of every make of camera are rife with complaints about their favorite makes TTL, P-TTL, E-TTL, etc. flash functions. It's almost enough to make one give up on flash photography entirely; until one looks at some well-lit images and compares them to the images from my camera...yikes.

Joe McNally (I'm currently reading his book "Hot Shoe Diaries") shoots a lot (professionally, for little-known publications like "National Geographic", "Life" and "Sports Illustrated") with his Nikons using the Nikon flash system, including TTL. He discusses at length the pitfalls of the Nikon system, and how it interacts with the environment, and, most importantly, with the photographer. He tells of shoots where the TTL has worked great, and others where, in his expert hands, it has failed completely. That's discussing a system that many think is the best camera flash system around (caveat: I've never used Nikons, so what do I know...I know a little about Pentax, and that's about it; I have no idea how Canon's flash system rates, it depends on which forum post you read). There are quite a few posts on this forum regarding P-TTL (the Pentax TTL system), with some reporting significant problems and others reporting that, for them, it works great. The only conclusion I can draw based on this is that for some these systems don't work and for others they work great. Looking at Nikon and Canon forums, I come to the same conclusion regarding their systems. The conclusion that I've drawn from McNally's books is that the photographer needs to be flexible and have a lot of options in his armamentarium in order to achieve the desired exposure. Bottom line, I'm in trouble.

Note the discussion in the RiceHigh thread. RiceHigh thinks he's found flash Nirvana: just put the Canon flash on your Pentax and all of your P-TTL shots will be keepers. Others say that, with their systems, his solution doesn't work at all. Others say, buy this other flash, it'll work great! That discussion, like pretty much every flash discussion I've read, anywhere, is all over the map. I've come to the conclusion that what works is very individual, depending on a mix of equipment, technical know-how with the flash, overall photographic skill, and shooting subjects and environments. What works today may not work worth a darn tomorrow.

I myself am shooting with a new Metz 58 AF2. Everyone should brace themselves for one of two upcoming posts from me: either I will be praising my K-5/Metz combo to the high heavens or I will be trashing those pieces of junk. At least, based on numerous threads on numerous camera fora, this is what I will do. It doesn't appear that I will be taking any sort of middle-ground stance.

02-13-2013, 05:28 PM   #5
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I haven't used flash for 45 years, but I still have a couple cartons of flash bulbs from my college years when I switched completely to available light. The last flash I tried was a Honeywell Strobonar 400 with handgrip and bracket for my H1a. I used an LX for years that supported TTL, but have always preferred to find the pictures available with existing light sources.
02-13-2013, 06:03 PM   #6
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QuoteOriginally posted by robissme Quote
Found this link about k-5.
RiceHigh's Pentax Blog: Pathetic Canon's External Auto Saves the Pathetic TTL of Pentax!

Someone know what this issue is about?, never heard of it before.
A warning: take what you read on RiceHigh's Pentax Blog, or anywhere else for that matter, with a grain of salt. Ask around (like you did here), and if in doubt and if possible, do the experiment yourself. Nothing can beat real life experience.

I assume you already know the difference between different flash modes (manual, auto, TTL, and p-TTL). If not, please ask.

Pentax's p-TTL started with the K10D (it was TTL before that). The original implementation of p-TTL was terrible: inconsistent, easy to be fooled by under/over reflective objects. This continued up to the K20D (including the "lesser" models: K100D, K100D Super, K110D, K2000 or K-M). With my K10D, I just stay clear from p-TTL.

p-TTL was vastly improved in K-7 and subsequent models. There were minor issues but they were bugs, not major design/implementation problems. In terms of exposure accuracy, I'd rate it comparable to its Canon, Nikon, ...., counterparts. (Feature-wise, I think Pentax is still behind, however).

In general, I still don't like flash mode that has a preflash strobe. This includes Pentax's p-TTL, Nikon's i-TTL, Canon's e-TTL, and others. The main reason is that many people (and animals) blink their eyes in reacting to the preflash strobe. Their eyes are more likely to close during actual exposure. For group photos, I don't use p-TTL at all. Another reason is that I use cameras of different brands. "Dedicated" flash mode then becomes useless with a "foreign" camera body.

So what do I use? Auto flash mode, just as "featured" in the article on RiceHigh's Pentax Blog. This mode has been around for decades, and is still available on many current flash units. Pentax AF360FGZ and AF540FGZ have it, so do many Metz models. In fact, one of my rules is "I don't buy any flash that is without auto mode."

In many cases, you can't avoid p-TTL: wireless (using Pentax's optical protocol), high-speed sync. In other cases, p-TTL significant improves the chance of correct exposure: macro, lens using filter.

There, you have it. There is nothing magic about Canon flash. RiceHigh could have used a Pentax AF360FGZ or AF540FGZ in auto mode for the same result (but saying "Pentax flash in auto mode saves Pentax's day" does not sound as dramatic as "Canon flash saves Pentax's day").
02-14-2013, 07:59 PM   #7
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QuoteOriginally posted by SOldBear Quote
A warning: take what you read on RiceHigh's Pentax Blog, or anywhere else for that matter, with a grain of salt. Ask around (like you did here), and if in doubt and if possible, do the experiment yourself. Nothing can beat real life experience.
how true
QuoteQuote:

I assume you already know the difference between different flash modes (manual, auto, TTL, and p-TTL). If not, please ask.

Pentax's p-TTL started with the K10D (it was TTL before that). The original implementation of p-TTL was terrible: inconsistent, easy to be fooled by under/over reflective objects. This continued up to the K20D (including the "lesser" models: K100D, K100D Super, K110D, K2000 or K-M). With my K10D, I just stay clear from p-TTL.
. Not true. Every Pentax camera DSLR starting with the *istD. But, the *istD, DS and DS2 also supported TTL.

QuoteQuote:

p-TTL was vastly improved in K-7 and subsequent models. There were minor issues but they were bugs, not major design/implementation problems. In terms of exposure accuracy, I'd rate it comparable to its Canon, Nikon, ...., counterparts. (Feature-wise, I think Pentax is still behind, however).
the improvements largely came from the 77 segment metering over the 11 segment metering used previously. Since P-TTL uses the cameras standard metering any improvement in regular metering helps p-TTL also
QuoteQuote:

In general, I still don't like flash mode that has a preflash strobe. This includes Pentax's p-TTL, Nikon's i-TTL, Canon's e-TTL, and others. The main reason is that many people (and animals) blink their eyes in reacting to the preflash strobe. Their eyes are more likely to close during actual exposure. For group photos, I don't use p-TTL at all. Another reason is that I use cameras of different brands. "Dedicated" flash mode then becomes useless with a "foreign" camera body.
this is very true
QuoteQuote:

So what do I use? Auto flash mode, just as "featured" in the article on RiceHigh's Pentax Blog. This mode has been around for decades, and is still available on many current flash units. Pentax AF360FGZ and AF540FGZ have it, so do many Metz models. In fact, one of my rules is "I don't buy any flash that is without auto mode."

In many cases, you can't avoid p-TTL: wireless (using Pentax's optical protocol), high-speed sync. In other cases, p-TTL significant improves the chance of correct exposure: macro, lens using filter.

There, you have it. There is nothing magic about Canon flash. RiceHigh could have used a Pentax AF360FGZ or AF540FGZ in auto mode for the same result (but saying "Pentax flash in auto mode saves Pentax's day" does not sound as dramatic as "Canon flash saves Pentax's day").
i would disagree, it's better to get an *istD and shoot TTL than auto mode
02-15-2013, 11:49 AM   #8
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I have the exact same capabilities with my Vivitar 550FD as RiceHigh's Canon flash on my K-r. This is a TTL (not P-TTL) flash from my Pentax Super Program. It includes the same "external TTL" .... which isn't TTL at all. This is an auto-thyristor sensor that looks at the scene much the same way as an in-camera sensor and quenches the flash when the sensor determines full exposure has occurred. The biggest difference between using the camera's built-in sensor(s) and the flash's sensor is the flash sensor likely isn't using the same viewing angles as your camera's lens and therefore may come up with a different exposure calculation.

I use either the above Vivitar flash or my Sigma EF610 DG Super flash depending on the subject and my mood at the time. Sometimes I shoot full manual, sometimes I shoot auto-thyristor, and sometimes I shoot P-TTL. Each has pros & cons.

02-16-2013, 06:48 AM   #9
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Metz 58 AF2

QuoteOriginally posted by stens Quote
P-TTL and TTL are attractive, in that the camera is analyzing the light actually coming through the lens and interacting with the flash to provide the perfect exposure every time.

However....the cameras are doing this with algorithms, not with a photographer's eye. They're trying to center that histogram and expose everything optimally, which we photographers might not want. Furthermore, the cameras are frequently trying to adequately expose everything in a frame in which it is impossible to adequately expose every portion of the frame.

Even more problematic, there is frequently variation in metering between shots as light changes, if the photographer doesn't completely control the light, including providing a completely stable camera position and a completely stable subject. One shot might be great, the next underexposed or blown out. There is a lot of variability in metering. I mean, unless you are lighting inanimate objects in a studio, there are changes in ambient light, changes in camera position (even subtle ones, only the tripod holds the camera steady), changes in environment (including all reflective surfaces) and changes in subject orientation to the light as the subjects move or are rearranged. Please note that forums of every make of camera are rife with complaints about their favorite makes TTL, P-TTL, E-TTL, etc. flash functions. It's almost enough to make one give up on flash photography entirely; until one looks at some well-lit images and compares them to the images from my camera...yikes.

Joe McNally (I'm currently reading his book "Hot Shoe Diaries") shoots a lot (professionally, for little-known publications like "National Geographic", "Life" and "Sports Illustrated") with his Nikons using the Nikon flash system, including TTL. He discusses at length the pitfalls of the Nikon system, and how it interacts with the environment, and, most importantly, with the photographer. He tells of shoots where the TTL has worked great, and others where, in his expert hands, it has failed completely. That's discussing a system that many think is the best camera flash system around (caveat: I've never used Nikons, so what do I know...I know a little about Pentax, and that's about it; I have no idea how Canon's flash system rates, it depends on which forum post you read). There are quite a few posts on this forum regarding P-TTL (the Pentax TTL system), with some reporting significant problems and others reporting that, for them, it works great. The only conclusion I can draw based on this is that for some these systems don't work and for others they work great. Looking at Nikon and Canon forums, I come to the same conclusion regarding their systems. The conclusion that I've drawn from McNally's books is that the photographer needs to be flexible and have a lot of options in his armamentarium in order to achieve the desired exposure. Bottom line, I'm in trouble.

Note the discussion in the RiceHigh thread. RiceHigh thinks he's found flash Nirvana: just put the Canon flash on your Pentax and all of your P-TTL shots will be keepers. Others say that, with their systems, his solution doesn't work at all. Others say, buy this other flash, it'll work great! That discussion, like pretty much every flash discussion I've read, anywhere, is all over the map. I've come to the conclusion that what works is very individual, depending on a mix of equipment, technical know-how with the flash, overall photographic skill, and shooting subjects and environments. What works today may not work worth a darn tomorrow.

I myself am shooting with a new Metz 58 AF2. Everyone should brace themselves for one of two upcoming posts from me: either I will be praising my K-5/Metz combo to the high heavens or I will be trashing those pieces of junk. At least, based on numerous threads on numerous camera fora, this is what I will do. It doesn't appear that I will be taking any sort of middle-ground stance.
Interesting Im intend to buy one Metz 58 AF2 but tho im a canon user too, i google around a bit for of-camera HSS flashing. Is it possible to do HSS of camera shooting with a k-5 II and a Metz 58 AF2? is there a wireless flashtrigger on the market that do the trick or is there a hotshoe-cord to buy somwhere? i Really would like to buy a wireless HSS solution but it seems not that somethning like that is out in the market, and i didnt find any hotshoe-cord either.
02-16-2013, 08:48 AM   #10
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QuoteOriginally posted by robissme Quote
i Really would like to buy a wireless HSS solution but it seems not that somethning like that is out in the market, and i didnt find any hotshoe-cord either.
I posted a reply in the thread you originated.
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