P-TTL flash - is it necessary ?

Wheatfield · 10-24-2010, 09:37 PM

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Originally posted by Adam

Old TTL flashes will work on PTTL-only bodies, but they will always fire at full power. You will have to adjust aperture manually and set your shutter speed to whatever the given flash is set/designed to sync at.

Generally, these flashes have an auto setting where the flash controls it's own output. My experience is this is sufficiently accurate (quite often more accurate than the camera's flash control).

**bkpix** · 10-24-2010, 09:39 PM

Old Pentax 280T can be set to auto, which works quite well. I own one and use it all the time. 50 pounds, though, is probably kind of high.

newarts · 10-25-2010, 04:36 AM

Why not get a P-TTL flash? The 138ft $76 Rokinon D900AFZ-P Rokinon D900AFZ-P Zoom Flash Digital Camera for Pentax Cameras | Overstock.com

I have found no fault with this flash; it works well on camera and off camera with a wire. (It does not do P-TTL in off-camera wireless mode, so I bought a $26 wire.)

User comments imply the 148ft $100 Rokinon 980 works in wireless mode but I can't confirm that - when an ad says "works as wireless slave" it does not necessarily mean doing P-TTL in wireless mode - it may mean that it flashes at full strength when triggered optically.

Dave

Arjay Bee · 10-25-2010, 06:01 AM

Provided you personally test trigger voltage go with what you can get.

Example: I regularly use a Nissin 5200G Auto Thyristor potato masher plugged into the xsynch socket of a K20D. This is a very powerful flash that can fill a a stage or give subtle fill in more intimate shady settings.

This setup, as a poster above says, allows you to set the aperture to match the distance and output. The device has the ability to physically switch down to 1/16 of full flash which is also offered on many other old style flashes. This is great for daylight fill.

Using the dials and switches on top of the flash to physically vary the output, and using the wide angle diffuser that came with the flash at lots of other times allows for a lot of flexibility.

Another advantage to digital is that over exposures and under exposures can be used to adjust the aperture and images reshot. Instant feedback and modification.

rockmaster1964 · 10-25-2010, 10:00 AM

Originally posted by snostorm

Hi Squier,

The AF 280T is a TTL flash, and since the K200D does not have the required sensor in the camera body, this mode will not give you any exposure automation. It also has an Auto Thyristor mode though, so if you don't mind setting the ISO and aperture, then being limited to the indicated distance ranges, it's a very nicely made gun. Auto mode has the advantages of no preflash and the flash will work similarly on any camera with a hotshoe with no brand dedication.

It has the disadvantage of not communicating with the camera, so it won't meter through the lens, nor will it meter outside of its set ISO range without some extrapolation of the aperture/distance scale (which is easy enough, but requires some attention).

That being said, I think that 50 GBP is probably a bit pricey. I paid $23 USD (shipped) for mine about 4 years ago, but it was priced under the market at the time.

Scott

The AF280T can communicate with the body of the camera. The flash can tell the body what to set the aperture and shutter speed to based on what mode the camera is on. I use AV mode and it adjusts my shutter speed based on the focal length. Of coarse you can't use TTL, but the auto mode works better than PTTL. The flash indicator in the view finder also works.

Squier · 10-25-2010, 10:49 AM

Some great help here guys, thank you

The one thing that worries me, is buying a flash unit that is not dedicated pentax fit. There's a massive amount of flash units available for a lot cheaper than the AF280T i saw, but many of the sellers have not listed which camera they fit.

Should i only buy dedicated flashes that state they fit Pentax KA hot shoe mount ? Like the Rokinon newarts posted

Squier · 10-25-2010, 10:58 AM

Arjay - why use the xsync socket, rather than the hot shoe, with an extension sync curly cable ?

fotaki · 10-25-2010, 11:45 AM

Squier......Have you tried - Heritage Cameras items - Get great deals on AF lenses, Digital lenses items on eBay.co.uk Shops! ? A UK company.

I bought a nice S/H Topca 330CX (French made) flash from them a while ago - purchased to supplement existing flash. They do give good info on all their items and a lot of the flash equipment they sell is Pentax dedicated.

newarts · 10-25-2010, 11:48 AM

Originally posted by Squier

Some great help here guys, thank you

The one thing that worries me, is buying a flash unit that is not dedicated pentax fit. There's a massive amount of flash units available for a lot cheaper than the AF280T i saw, but many of the sellers have not listed which camera they fit.

Should i only buy dedicated flashes that state they fit Pentax KA hot shoe mount ? Like the Rokinon newarts posted

The Rokinons I listed earlier are made to function correctly with Pentax P-TTL if that's what you mean by "dedicated pentax fit". Yes their firmware and features are exactly those for Pentax P-TTL so far as I know.

One function they don't support is P-TTL by optical wireless as far as I know, but they do function in P-TTL with a wire.

Your topic title was "P-TTL flash - is it necessary ?". The answer is that it is extremely useful. Of course it isn't absolutely necessary as you can use a manual flash, just like you can turn off all your camera's automatic functions, but those functions, like the P-TTL flash are awfully convenient most of the time.

I say get a P-TTL flash & use it in manual mode when you must. I've found the Rokinon to work well and I've heard no contrary evidence.

I first got a manual/auto flash to use with my Pentax DSLRs, then got the Rokinon; I've not used the manual/auto flash since, even though I've long experience with manual/auto flashes (or maybe *because* I've long experience with manual flashes.)

Dave

Squier · 10-25-2010, 12:03 PM

fotaki - thanks for the link, have that open now and reading

newarts, thanks again. Seems there's a premium to pay for P-TTL, and as i'm fairly happy using my Camera in Manual mode, i should be ok with using any flash in manual mode too. Just got to get to grips with how manual / flash works

Good help here though, so shouldnt be a problem

noblepa · 10-25-2010, 12:18 PM

Originally posted by Squier

Some great help here guys, thank you

The one thing that worries me, is buying a flash unit that is not dedicated pentax fit. There's a massive amount of flash units available for a lot cheaper than the AF280T i saw, but many of the sellers have not listed which camera they fit.

Should i only buy dedicated flashes that state they fit Pentax KA hot shoe mount ? Like the Rokinon newarts posted

Your K200D won't do TTL flash control, only P-TTL. If you don't get a TTL or P-TTL flash, then the "dedication" of the flash doesn't mean very much. The very earliest "dedicated" flashes did little more than tell the camera that a flash was mounted and ready to fire. Sometimes, the camera would refuse to trip the shutter until the flash was fully charged. On some, the "dedication" was as little as displaying a light in the viewfinder when the flash was charged.

My point is that, if you're going to use a manual or "auto" flash (with the sensor in the flash, rather than the camera), then the dedication isn't important.

Just make sure that the flash is not too completely dedicated to another brand of camera. Some Sony and Canon cameras use a different hotshoe configuration. Flashes made for those cameras may not fire, even in manual mode, on a Pentax camera. OTOH, Nikon SB25 flashes are known to work well on Pentax cameras.

Back in the film days, before TTL flash control, there were a lot of flash makers out there who made un-dedicated flashes that worked well with any camera that had a standard hotshoe. In its simplest form, all a flash needs the camera to do is short the center contact to the side contact on the hotshoe. This is what triggers the flash. All those other pins on the hotshoe are for flash control.

I use a Promaster 5500 flash. This unit uses interchangeable control units that change the dedication to various cameras. I use one with the thyristor light sensor builtin, meaning that it works in auto-flash mode. I could get a controller for Pentax TTL, Nikon TTL or others. It does not do any of the preflash TTL technologies. They have a different model for that.

BTW, as far as I know, all Vivitar 295HV's are safe to use on a modern dslr. Don't confuse the 285HV with the 285 (non-HV version) which can have a very high trigger voltage. I think that all Vivitar 283's are unsafe. Any flash can be used safely if you use a Wein Safe-Sync, which drops the trigger voltage to a safe level and adds a PC socket, to boot.

Squier · 10-25-2010, 12:26 PM

Thanks for that - fabulous help

Here's what i've found only in the last 5 minutes of searching.

Sunpak 431 Auto Thyristor ( not dedicated presumbaly ) £15 including delivery.

Jessops Pentax 280 AFP £11.50 including delivery

They both appear to be tilt and swivel, which is what i want. But as for the performance or ease of use, i have no idea

SOldBear · 10-25-2010, 12:33 PM

I mostly agree with the post above, but would like to clarify this:

Originally posted by noblepa

I think that all Vivitar 283's are unsafe.

Actually some Vivitar 283's have trigger voltage less than 10V, and thus are safe. At one point I had 3 283 units, 2 with 8.5V trigger voltage, and 1 with 183V.

About other inexpensive flash units, please read this post.

Squier · 10-25-2010, 12:47 PM

Thanks Bear - have bookmarked the post

I'm ok with checking Voltages with a DVM too, so i would check any flash that i bought to be sure

noblepa · 10-25-2010, 04:07 PM

Originally posted by SOldBear

Actually some Vivitar 283's have trigger voltage less than 10V, and thus are safe. At one point I had 3 283 units, 2 with 8.5V trigger voltage, and 1 with 183V.

About other inexpensive flash units, please read this post.

I stand corrected, then. I would still argue that any older flash should be tested with a digital voltmeter to verify that the trigger voltage is safe.

10-25-2010, 04:36 AM	#18
newarts Inactive Account Join Date: Dec 2008 Location: Ames, Iowa, USA Photos: Albums Posts: 2,965	Why not get a P-TTL flash? The 138ft $76 Rokinon D900AFZ-P Rokinon D900AFZ-P Zoom Flash Digital Camera for Pentax Cameras \| Overstock.com I have found no fault with this flash; it works well on camera and off camera with a wire. (It does not do P-TTL in off-camera wireless mode, so I bought a $26 wire.) User comments imply the 148ft $100 Rokinon 980 works in wireless mode but I can't confirm that - when an ad says "works as wireless slave" it does not necessarily mean doing P-TTL in wireless mode - it may mean that it flashes at full strength when triggered optically. Dave Last edited by newarts; 10-25-2010 at 04:46 AM.

10-25-2010, 10:49 AM	#21
Squier Veteran Member Join Date: Apr 2009 Location: Oxfordshire UK Photos: Albums Posts: 706 Original Poster	Some great help here guys, thank you The one thing that worries me, is buying a flash unit that is not dedicated pentax fit. There's a massive amount of flash units available for a lot cheaper than the AF280T i saw, but many of the sellers have not listed which camera they fit. Should i only buy dedicated flashes that state they fit Pentax KA hot shoe mount ? Like the Rokinon newarts posted Last edited by Squier; 10-25-2010 at 10:54 AM.

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10-24-2010, 09:37 PM	#16
Wheatfield Moderator Join Date: Apr 2008 Location: The wheatfields of Canada Posts: 15,976	Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here. Originally posted by Adam Old TTL flashes will work on PTTL-only bodies, but they will always fire at full power. You will have to adjust aperture manually and set your shutter speed to whatever the given flash is set/designed to sync at. Generally, these flashes have an auto setting where the flash controls it's own output. My experience is this is sufficiently accurate (quite often more accurate than the camera's flash control).

10-24-2010, 09:39 PM	#17
bkpix Site Supporter Join Date: Feb 2010 Location: Creswell, Oregon Photos: Albums Posts: 568	Old Pentax 280T can be set to auto, which works quite well. I own one and use it all the time. 50 pounds, though, is probably kind of high.

10-25-2010, 06:01 AM	#19
Arjay Bee Pentaxian Join Date: Sep 2006 Location: Horn Island, Torres Straits, Q Photos: Gallery Posts: 4,715	Provided you personally test trigger voltage go with what you can get. Example: I regularly use a Nissin 5200G Auto Thyristor potato masher plugged into the xsynch socket of a K20D. This is a very powerful flash that can fill a a stage or give subtle fill in more intimate shady settings. This setup, as a poster above says, allows you to set the aperture to match the distance and output. The device has the ability to physically switch down to 1/16 of full flash which is also offered on many other old style flashes. This is great for daylight fill. Using the dials and switches on top of the flash to physically vary the output, and using the wide angle diffuser that came with the flash at lots of other times allows for a lot of flexibility. Another advantage to digital is that over exposures and under exposures can be used to adjust the aperture and images reshot. Instant feedback and modification.

10-25-2010, 10:00 AM	#20
rockmaster1964 Veteran Member Join Date: Oct 2008 Location: Frisco Texas Photos: Gallery Posts: 382	Originally posted by snostorm Hi Squier, The AF 280T is a TTL flash, and since the K200D does not have the required sensor in the camera body, this mode will not give you any exposure automation. It also has an Auto Thyristor mode though, so if you don't mind setting the ISO and aperture, then being limited to the indicated distance ranges, it's a very nicely made gun. Auto mode has the advantages of no preflash and the flash will work similarly on any camera with a hotshoe with no brand dedication. It has the disadvantage of not communicating with the camera, so it won't meter through the lens, nor will it meter outside of its set ISO range without some extrapolation of the aperture/distance scale (which is easy enough, but requires some attention). That being said, I think that 50 GBP is probably a bit pricey. I paid $23 USD (shipped) for mine about 4 years ago, but it was priced under the market at the time. Scott The AF280T can communicate with the body of the camera. The flash can tell the body what to set the aperture and shutter speed to based on what mode the camera is on. I use AV mode and it adjusts my shutter speed based on the focal length. Of coarse you can't use TTL, but the auto mode works better than PTTL. The flash indicator in the view finder also works.

10-25-2010, 10:58 AM	#22
Squier Veteran Member Join Date: Apr 2009 Location: Oxfordshire UK Photos: Albums Posts: 706 Original Poster	Arjay - why use the xsync socket, rather than the hot shoe, with an extension sync curly cable ?

10-25-2010, 11:45 AM	#23
fotaki Veteran Member Join Date: Aug 2008 Location: Greece and UK Photos: Gallery \| Albums Posts: 309	Squier......Have you tried - Heritage Cameras items - Get great deals on AF lenses, Digital lenses items on eBay.co.uk Shops! ? A UK company. I bought a nice S/H Topca 330CX (French made) flash from them a while ago - purchased to supplement existing flash. They do give good info on all their items and a lot of the flash equipment they sell is Pentax dedicated.

10-25-2010, 11:48 AM	#24
newarts Inactive Account Join Date: Dec 2008 Location: Ames, Iowa, USA Photos: Albums Posts: 2,965	Originally posted by Squier Some great help here guys, thank you The one thing that worries me, is buying a flash unit that is not dedicated pentax fit. There's a massive amount of flash units available for a lot cheaper than the AF280T i saw, but many of the sellers have not listed which camera they fit. Should i only buy dedicated flashes that state they fit Pentax KA hot shoe mount ? Like the Rokinon newarts posted The Rokinons I listed earlier are made to function correctly with Pentax P-TTL if that's what you mean by "dedicated pentax fit". Yes their firmware and features are exactly those for Pentax P-TTL so far as I know. One function they don't support is P-TTL by optical wireless as far as I know, but they do function in P-TTL with a wire. Your topic title was "P-TTL flash - is it necessary ?". The answer is that it is extremely useful. Of course it isn't absolutely necessary as you can use a manual flash, just like you can turn off all your camera's automatic functions, but those functions, like the P-TTL flash are awfully convenient most of the time. I say get a P-TTL flash & use it in manual mode when you must. I've found the Rokinon to work well and I've heard no contrary evidence. I first got a manual/auto flash to use with my Pentax DSLRs, then got the Rokinon; I've not used the manual/auto flash since, even though I've long experience with manual/auto flashes (or maybe because I've long experience with manual flashes.) Dave

10-25-2010, 12:03 PM	#25
Squier Veteran Member Join Date: Apr 2009 Location: Oxfordshire UK Photos: Albums Posts: 706 Original Poster	fotaki - thanks for the link, have that open now and reading newarts, thanks again. Seems there's a premium to pay for P-TTL, and as i'm fairly happy using my Camera in Manual mode, i should be ok with using any flash in manual mode too. Just got to get to grips with how manual / flash works Good help here though, so shouldnt be a problem

10-25-2010, 12:18 PM	#26
noblepa Veteran Member Join Date: Sep 2007 Location: Bay Village, Ohio USA Posts: 1,142	Originally posted by Squier Some great help here guys, thank you The one thing that worries me, is buying a flash unit that is not dedicated pentax fit. There's a massive amount of flash units available for a lot cheaper than the AF280T i saw, but many of the sellers have not listed which camera they fit. Should i only buy dedicated flashes that state they fit Pentax KA hot shoe mount ? Like the Rokinon newarts posted Your K200D won't do TTL flash control, only P-TTL. If you don't get a TTL or P-TTL flash, then the "dedication" of the flash doesn't mean very much. The very earliest "dedicated" flashes did little more than tell the camera that a flash was mounted and ready to fire. Sometimes, the camera would refuse to trip the shutter until the flash was fully charged. On some, the "dedication" was as little as displaying a light in the viewfinder when the flash was charged. My point is that, if you're going to use a manual or "auto" flash (with the sensor in the flash, rather than the camera), then the dedication isn't important. Just make sure that the flash is not too completely dedicated to another brand of camera. Some Sony and Canon cameras use a different hotshoe configuration. Flashes made for those cameras may not fire, even in manual mode, on a Pentax camera. OTOH, Nikon SB25 flashes are known to work well on Pentax cameras. Back in the film days, before TTL flash control, there were a lot of flash makers out there who made un-dedicated flashes that worked well with any camera that had a standard hotshoe. In its simplest form, all a flash needs the camera to do is short the center contact to the side contact on the hotshoe. This is what triggers the flash. All those other pins on the hotshoe are for flash control. I use a Promaster 5500 flash. This unit uses interchangeable control units that change the dedication to various cameras. I use one with the thyristor light sensor builtin, meaning that it works in auto-flash mode. I could get a controller for Pentax TTL, Nikon TTL or others. It does not do any of the preflash TTL technologies. They have a different model for that. BTW, as far as I know, all Vivitar 295HV's are safe to use on a modern dslr. Don't confuse the 285HV with the 285 (non-HV version) which can have a very high trigger voltage. I think that all Vivitar 283's are unsafe. Any flash can be used safely if you use a Wein Safe-Sync, which drops the trigger voltage to a safe level and adds a PC socket, to boot.

10-25-2010, 12:33 PM	#28
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	I mostly agree with the post above, but would like to clarify this: Originally posted by noblepa I think that all Vivitar 283's are unsafe. Actually some Vivitar 283's have trigger voltage less than 10V, and thus are safe. At one point I had 3 283 units, 2 with 8.5V trigger voltage, and 1 with 183V. About other inexpensive flash units, please read this post.

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10-25-2010, 12:47 PM	#29
Squier Veteran Member Join Date: Apr 2009 Location: Oxfordshire UK Photos: Albums Posts: 706 Original Poster	Thanks Bear - have bookmarked the post I'm ok with checking Voltages with a DVM too, so i would check any flash that i bought to be sure

10-25-2010, 04:07 PM	#30
noblepa Veteran Member Join Date: Sep 2007 Location: Bay Village, Ohio USA Posts: 1,142	Originally posted by SOldBear Actually some Vivitar 283's have trigger voltage less than 10V, and thus are safe. At one point I had 3 283 units, 2 with 8.5V trigger voltage, and 1 with 183V. About other inexpensive flash units, please read this post. I stand corrected, then. I would still argue that any older flash should be tested with a digital voltmeter to verify that the trigger voltage is safe.