360 flash

dafiryde · 10-18-2008, 01:01 PM

last night while using my flash i noticed with the 50-135 lens, that on the flash at max zoom was indicating 85, and when you depress the shutter button to lock focus the number changes to 58, but yet the zoom position in the flash remains unchanged.
is this 58 representing 85 in 35mm terms
or am i only getting 58 zoom position on the flash because i am using digital?

Dave

AVANT · 10-19-2008, 12:16 PM

58 * 1.5 = 85

The 85 is 35mm equiv

The 540 is no different, it doesn't zoom our very far. One of their shortcomings.

dafiryde · 10-19-2008, 12:27 PM

Originally posted by AVANT

58 * 1.5 = 85

The 85 is 35mm equiv

The 540 is no different, it doesn't zoom our very far. One of their shortcomings.

so would it be safe to say , that because we are using digal format that we are not getting the true output from our flash

Dave

AVANT · 10-19-2008, 03:55 PM

Originally posted by dafiryde

so would it be safe to say , that because we are using digal format that we are not getting the true output from our flash

Dave

Actually, you're getting it backwards.

The output is no different, it's all about the field of view.

Your zoom head does go to 85mm. However, 85mm on the flash, will cover the same field of view as a 58mm lens on a 1.5x crop factor sensor.

The number displayed under the digital format is the zoom of the flash in 35mm divided by 1.5. This is so you can match up the same numbers and be rest assured that they are covering the same area.

If you were to connect a full frame camera, it will just display 85mm instead of 58. It does not make the flash any stronger or weaker.

Sorry if I confused you with my previous post. Hope this makes more sense.

SpecialK · 10-19-2008, 05:54 PM

The 360 does not have the "digital format" reading that the 540 has, so the math looks funny, I think.

360
Attachment 20681

540
Attachment 20682

dafiryde · 10-19-2008, 08:30 PM

so why is it when i zoom back the lens to 50 the flash lcd panel says 48

Dave

AVANT · 10-20-2008, 12:38 AM

2 ways of thinking:

1)
50mm focal length lens = 75mm FOV in 35mm equiv.
Since the FOV is comparable to a 75mm lens, the flash selects 70mm (in 35mm) on the zoom head. This translates into the 48mm setting on the digital format readout

2)
You're using 50mm lens, the zoom head picks 48 in the digital scale because it's the closes setting to your 50mm focal length.

dafiryde · 10-20-2008, 03:50 PM

Originally posted by AVANT

2 ways of thinking:

1)
50mm focal length lens = 75mm FOV in 35mm equiv.
Since the FOV is comparable to a 75mm lens, the flash selects 70mm (in 35mm) on the zoom head. This translates into the 48mm setting on the digital format readout

2)
You're using 50mm lens, the zoom head picks 48 in the digital scale because it's the closes setting to your 50mm focal length.

#1 makes sence,
i think my issue is that, i was wondering if i am getting less flash outout, as i find that i dont see much difference between onboard flash and the 360.
so when i saw this reading on the flash as compared to lens setting on the barell, i wondered if this is why. or am i really getting less flash output.

Dave

dafiryde · 10-28-2008, 06:07 AM

amazing
i have read the K10D manual at least a 100 times and only this morning i saw page 180 that explains this

Dave

10-19-2008, 05:54 PM	#5
SpecialK Pentaxian Join Date: Dec 2006 Location: So California Photos: Gallery Posts: 16,480	The 360 does not have the "digital format" reading that the 540 has, so the math looks funny, I think. 360 Attachment 20681 540 Attachment 20682 Last edited by SpecialK; 02-02-2011 at 08:31 PM.

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10-18-2008, 01:01 PM	#1
dafiryde Veteran Member Join Date: Nov 2007 Location: Trinidad and Tobago Posts: 419	360 flash last night while using my flash i noticed with the 50-135 lens, that on the flash at max zoom was indicating 85, and when you depress the shutter button to lock focus the number changes to 58, but yet the zoom position in the flash remains unchanged. is this 58 representing 85 in 35mm terms or am i only getting 58 zoom position on the flash because i am using digital? Dave

10-19-2008, 12:16 PM	#2
AVANT Veteran Member Join Date: Jun 2007 Location: California Posts: 426	58 * 1.5 = 85 The 85 is 35mm equiv The 540 is no different, it doesn't zoom our very far. One of their shortcomings.

10-19-2008, 12:27 PM	#3
dafiryde Veteran Member Join Date: Nov 2007 Location: Trinidad and Tobago Posts: 419 Original Poster	Originally posted by AVANT 58 * 1.5 = 85 The 85 is 35mm equiv The 540 is no different, it doesn't zoom our very far. One of their shortcomings. so would it be safe to say , that because we are using digal format that we are not getting the true output from our flash Dave

10-19-2008, 03:55 PM	#4
AVANT Veteran Member Join Date: Jun 2007 Location: California Posts: 426	Originally posted by dafiryde so would it be safe to say , that because we are using digal format that we are not getting the true output from our flash Dave Actually, you're getting it backwards. The output is no different, it's all about the field of view. Your zoom head does go to 85mm. However, 85mm on the flash, will cover the same field of view as a 58mm lens on a 1.5x crop factor sensor. The number displayed under the digital format is the zoom of the flash in 35mm divided by 1.5. This is so you can match up the same numbers and be rest assured that they are covering the same area. If you were to connect a full frame camera, it will just display 85mm instead of 58. It does not make the flash any stronger or weaker. Sorry if I confused you with my previous post. Hope this makes more sense.

10-19-2008, 08:30 PM	#6
dafiryde Veteran Member Join Date: Nov 2007 Location: Trinidad and Tobago Posts: 419 Original Poster	so why is it when i zoom back the lens to 50 the flash lcd panel says 48 Dave

10-20-2008, 12:38 AM	#7
AVANT Veteran Member Join Date: Jun 2007 Location: California Posts: 426	2 ways of thinking: 1) 50mm focal length lens = 75mm FOV in 35mm equiv. Since the FOV is comparable to a 75mm lens, the flash selects 70mm (in 35mm) on the zoom head. This translates into the 48mm setting on the digital format readout 2) You're using 50mm lens, the zoom head picks 48 in the digital scale because it's the closes setting to your 50mm focal length.

10-20-2008, 03:50 PM	#8
dafiryde Veteran Member Join Date: Nov 2007 Location: Trinidad and Tobago Posts: 419 Original Poster	Originally posted by AVANT 2 ways of thinking: 1) 50mm focal length lens = 75mm FOV in 35mm equiv. Since the FOV is comparable to a 75mm lens, the flash selects 70mm (in 35mm) on the zoom head. This translates into the 48mm setting on the digital format readout 2) You're using 50mm lens, the zoom head picks 48 in the digital scale because it's the closes setting to your 50mm focal length. #1 makes sence, i think my issue is that, i was wondering if i am getting less flash outout, as i find that i dont see much difference between onboard flash and the 360. so when i saw this reading on the flash as compared to lens setting on the barell, i wondered if this is why. or am i really getting less flash output. Dave

10-28-2008, 06:07 AM	#9
dafiryde Veteran Member Join Date: Nov 2007 Location: Trinidad and Tobago Posts: 419 Original Poster	amazing i have read the K10D manual at least a 100 times and only this morning i saw page 180 that explains this Dave