Flash in auto mode

polur101 · 03-01-2012, 09:44 AM

I always wished that I could use AF540FGZ in auto mode while using the camera in apperture or shutter priority modes. It was annoying to see that the flash reverted back to PTTL mode when you press the shutter button. Recently I by chance discovered a work around.

If you first put the camera in manual mode, then the flash in auto mode, later turn the dial on the camera to choose apperture priority it seems to stay in auto mode. I have K200D, haven't tried this on K20D.

Like to know what others find.

JohnX · 03-01-2012, 10:21 AM

Please excuse my ignorance, but what benefit do you get from this work-round please?

polur101 · 03-01-2012, 12:27 PM

It is widely believed (and I find it to be true) that Pentax has the least reliable of newer TTL systems. Unacceptable level of inconsistencies. Yes, I understand that a shiny object in the field can cause significant underexposure. It is not possible to scout for every reflective object in the field. Auto mode gives more reliable consistent exposure.

SOldBear · 03-01-2012, 01:29 PM

Metz flashes, at least the ones that I have (54MZ, 40MZ with appropriate SCA modules), have "smart auto" mode: set the camera in auto, and it will take the ISO and the aperture settings from the camera. When the flash is ready to fire, if the camera is in Av mode (the only mode I use besides M), the flash will set shutter speed on the camera between 1/30 and 1/180, depending on the focal length of the lens.

Also, it's known that p-TTL in Pentax K20D and older DSLRs is very unreliable. It is significantly improved starting with the K-7.

The AF540FGZ tries to go back to p-TTL whenever it has a chance. This is very annoying.

I don't have my 540 here to test, but as I remember, if you manage to set the flash to auto, and the camera to Tv, the camera will take the settings from the flash, which is the reverse from the way Metz flashes work. I'm not sure if I would call this "smart auto."

westmill · 03-01-2012, 01:47 PM

I thought auto was when the flash itself used a sensor built into some flash units, and measured reflected light ?
is this what we are talking about here ?

SOldBear · 03-01-2012, 01:50 PM

Originally posted by westmill

I thought auto was when the flash itself used a sensor built into some flash units, and measured reflected light ?
is this what we are talking about here ?

Yes. Yes.

westmill · 03-02-2012, 02:01 PM

I use the metz 50 on mine and unfortunately it doesnt give me the option for simple auto.
I used it for a christning last wk. it managed but i wasnt overly impressed. Luckily i shot RAW which gave enough leeway to put things on an acceptable level.
Ive used a few Auto flash guns in the past and tested them with a flash meter. I tried 2 vivitar guns which were very inaccurate and inconsistant.
The one flash I did try and bought and was superb and was spot on accuracy was the metz CLT 1 hammerhead !
If i was looking to go down this road, this would be the gun for me ! Well .... watever the latest version is now called lol.
If I remember correctly the only place it was out was F16 and that was only one third of a stop. Thats very very impressive !
PS.... Thank you SOldBear

03-01-2012, 09:44 AM	#1
polur101 Forum Member Join Date: Jun 2008 Location: Buffalo, NY Posts: 58	Flash in auto mode I always wished that I could use AF540FGZ in auto mode while using the camera in apperture or shutter priority modes. It was annoying to see that the flash reverted back to PTTL mode when you press the shutter button. Recently I by chance discovered a work around. If you first put the camera in manual mode, then the flash in auto mode, later turn the dial on the camera to choose apperture priority it seems to stay in auto mode. I have K200D, haven't tried this on K20D. Like to know what others find.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
k100 d super won't go into auto flash mode	tdmsu	Troubleshooting and Beginner Help	2	11-04-2011 05:17 AM
Auto ISO in Av Mode	v5planet	Troubleshooting and Beginner Help	8	03-30-2011 09:46 AM
Any Good TTL flash with Auto Mode?	liukaitc	Flashes, Lighting, and Studio	25	03-24-2011 11:40 PM
ISO and Auto Mode	VelvetFoot	Troubleshooting and Beginner Help	9	01-25-2011 05:19 AM
K-x auto mode question	retroflex	Pentax DSLR Discussion	7	11-18-2010 06:47 AM

03-01-2012, 10:21 AM	#2
JohnX Pentaxian Join Date: Jul 2009 Location: London Posts: 1,116	Please excuse my ignorance, but what benefit do you get from this work-round please?

03-01-2012, 12:27 PM	#3
polur101 Forum Member Join Date: Jun 2008 Location: Buffalo, NY Posts: 58 Original Poster	It is widely believed (and I find it to be true) that Pentax has the least reliable of newer TTL systems. Unacceptable level of inconsistencies. Yes, I understand that a shiny object in the field can cause significant underexposure. It is not possible to scout for every reflective object in the field. Auto mode gives more reliable consistent exposure.

03-01-2012, 01:29 PM	#4
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	Metz flashes, at least the ones that I have (54MZ, 40MZ with appropriate SCA modules), have "smart auto" mode: set the camera in auto, and it will take the ISO and the aperture settings from the camera. When the flash is ready to fire, if the camera is in Av mode (the only mode I use besides M), the flash will set shutter speed on the camera between 1/30 and 1/180, depending on the focal length of the lens. Also, it's known that p-TTL in Pentax K20D and older DSLRs is very unreliable. It is significantly improved starting with the K-7. The AF540FGZ tries to go back to p-TTL whenever it has a chance. This is very annoying. I don't have my 540 here to test, but as I remember, if you manage to set the flash to auto, and the camera to Tv, the camera will take the settings from the flash, which is the reverse from the way Metz flashes work. I'm not sure if I would call this "smart auto."

03-01-2012, 01:47 PM	#5
westmill Veteran Member Join Date: Jan 2012 Location: Stoke on Trent Photos: Gallery \| Albums Posts: 1,146	I thought auto was when the flash itself used a sensor built into some flash units, and measured reflected light ? is this what we are talking about here ?

03-01-2012, 01:50 PM	#6
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	Originally posted by westmill I thought auto was when the flash itself used a sensor built into some flash units, and measured reflected light ? is this what we are talking about here ? Yes. Yes.

03-02-2012, 02:01 PM	#7
westmill Veteran Member Join Date: Jan 2012 Location: Stoke on Trent Photos: Gallery \| Albums Posts: 1,146	I use the metz 50 on mine and unfortunately it doesnt give me the option for simple auto. I used it for a christning last wk. it managed but i wasnt overly impressed. Luckily i shot RAW which gave enough leeway to put things on an acceptable level. Ive used a few Auto flash guns in the past and tested them with a flash meter. I tried 2 vivitar guns which were very inaccurate and inconsistant. The one flash I did try and bought and was superb and was spot on accuracy was the metz CLT 1 hammerhead ! If i was looking to go down this road, this would be the gun for me ! Well .... watever the latest version is now called lol. If I remember correctly the only place it was out was F16 and that was only one third of a stop. Thats very very impressive ! PS.... Thank you SOldBear