Cactus V6 & External Light Meter?

glee46 · 06-19-2015, 01:18 PM

I know that Sekonic has a build in RX for Pocket Wizard. I jumped on board with 6 Cactus V6 and 4 flashes, thinking it would work with them. Are there any light meters anyone would recommend to work with the V6? Or, is there a work around to get the Sekonic to work with the Cactus?

panoguy · 06-19-2015, 01:44 PM - **1 Like**

Set your Sekonic's measuring mode to "Flash - cordless." The meter will then wait up to 90 seconds for a flash (dramatic increase in brightness) to measure the light. Just press the button on front of the V6 to trigger your flashes. Some Sekonics even have a "Flash - multiple" to measure cumulative effects, so you can move yourself out of the way if you're blocking a light, just by putting the flashes on different V6 channels and triggering them sequentially.

If you need a more responsive solution, Cactus makes a tiny little PC sync to 3.5mm phono cord that plugs into the V6 and then into the PC port on the light meter. Then you change the measuring mode to "Cord - PC" mode and the meter will trigger the flash, just like the PWiz, but with a dangly bit.

glee46 · 06-19-2015, 05:43 PM

Originally posted by panoguy

Set your Sekonic's measuring mode to "Flash - cordless." The meter will then wait up to 90 seconds for a flash (dramatic increase in brightness) to measure the light. Just press the button on front of the V6 to trigger your flashes. Some Sekonics even have a "Flash - multiple" to measure cumulative effects, so you can move yourself out of the way if you're blocking a light, just by putting the flashes on different V6 channels and triggering them sequentially.

If you need a more responsive solution, Cactus makes a tiny little PC sync to 3.5mm phono cord that plugs into the V6 and then into the PC port on the light meter. Then you change the measuring mode to "Cord - PC" mode and the meter will trigger the flash, just like the PWiz, but with a dangly bit.

Thanks Panoguy. I had a feeling there was a way to get it to work. I have the PC sync with an extra V6 to control the flash and shutter. I just wanted to make sure it worked before I dropped some big bucks on the Sekonic.

panoguy · 06-20-2015, 06:48 PM

Originally posted by glee46

Thanks Panoguy. I had a feeling there was a way to get it to work. I have the PC sync with an extra V6 to control the flash and shutter. I just wanted to make sure it worked before I dropped some big bucks on the Sekonic.

I'm using a Sekonic L478DR meter (even though I don't use PW's), and like all Sekonics it is expensive but full-featured and very accurate. It's also easy to understand; no tiny, cryptic display- just a big iPhone-like touchscreen. The only issue I have is that the touchscreen isn't very "touchy." Sometimes it takes a number of pokes or swipes to get it to respond. Good thing the meter button is a physical one!

glee46 · 06-21-2015, 09:40 AM

Originally posted by panoguy

I'm using a Sekonic L478DR meter (even though I don't use PW's), and like all Sekonics it is expensive but full-featured and very accurate. It's also easy to understand; no tiny, cryptic display- just a big iPhone-like touchscreen. The only issue I have is that the touchscreen isn't very "touchy." Sometimes it takes a number of pokes or swipes to get it to respond. Good thing the meter button is a physical one!

I'm torn between the L478DR and the L758DR. They have a a model L758D, without the PW controller in it, but it only sells in Europe. I guess I'm holding out that they might come up with a controller for the Cactus V6. It also seems that to get the profile of camera and lenses, one has to shell out another $100. Sort of a rip off.

It would be nice if Cactus came out with a light meter which works with all. The price would come down, and it would be a big win for us all.

philbaum · 06-26-2015, 11:20 AM

Originally posted by glee46

I'm torn between the L478DR and the L758DR. They have a a model L758D, without the PW controller in it, but it only sells in Europe. I guess I'm holding out that they might come up with a controller for the Cactus V6. It also seems that to get the profile of camera and lenses, one has to shell out another $100. Sort of a rip off.

It would be nice if Cactus came out with a light meter which works with all. The price would come down, and it would be a big win for us all.

Okay, i'll ask the dumb question : Why would one need a light meter? DSLRs generally show the EV level in manual mode. Or just take a digital picture and adjust from there. I can see the need for light meters in the days of film where one doesn't have any immediate feedback. But in the days of digital camera - Why?

Just trying to learn :-)

panoguy · 06-26-2015, 04:30 PM

Originally posted by philbaum

Okay, i'll ask the dumb question : Why would one need a light meter? DSLRs generally show the EV level in manual mode. Or just take a digital picture and adjust from there. I can see the need for light meters in the days of film where one doesn't have any immediate feedback. But in the days of digital camera - Why?

Just trying to learn :-)

#1 reason (realistically): for pros, if you have a paying client under your strobes, they don't want to see you chimping and adjusting your lights after each flash, long before you start to direct them into pose.

#2: camera meters are based on the light reflected from within the scene (so a black or white object will bias the meter), while incident light meters are based on light directed at the scene (colors and tones in the scene don't affect the light sources themselves). This gives consistency regardless of clothing choices and skin colors, and prevents the camera "thinking for you."

#3: multiple lights and ratios - a meter can figure that out for you, while no camera can do that... only lots of experience behind it.

#4: it looks really professional (no really, that's one of the reason people buy them!)

Class A · 06-26-2015, 11:51 PM

Originally posted by philbaum

Why would one need a light meter?

I agree with you that there is little motivation left to use an external light meter.

Panoguy's point #3 is the best argument remaining: While a meter cannot figure anything out automatically, using an external light meter is the quickest way to establish certain lighting ratios for multiple light sources (e.g., 1:3:4). This still isn't a silver bullet, as the ratio of a hair kicker may need to be 1/3 instead 1/4 of the key light, depending on the subject's hair colour, but it helps to get a reasonable starting point.

Having said that, often one will use one's lights in standard positions with standard distances to the subject and making the power settings manually from recorded notes is quicker than measuring the ratios again.

Regarding #2 from Panoguy's list: Light meters typically support both reflectance and incident metering because there is a use for both. Incident metering can sometimes be replaced by using spot reflectance metering and, again, is not a silver bullet because most of the time photography is not about achieving technically accurate exposures, but expressing artistic intent with deliberate under- or over-exposure.

Finally, I think points #1 and #4 are pretty much the same. With a bit of experience, obtaining the desired exposure without using a light meter does not take considerably longer. And if you want to really want to work professionally, you set up your lights with a test subject before the client comes into play anyhow.

philbaum · 06-27-2015, 12:09 AM

@Panoguy
@Class A,

Thanks for the answers guys - food for thought :-)

glee46 · 06-27-2015, 01:08 AM

So I went with the L758DR. I have a lot of manual lenses, and the difference in the time it takes and the results are worlds apart. Even with my Pentax 14mm 2.8 on my K-5 the difference in exposures make a huge difference as well. Right now, when I shoot outdoors with 4 flashes, (All on V6's with a V6 on TX to control them all) and a reflector, this light meter, and the V6, has given me control over picture outcome and time.

BrianR · 06-27-2015, 03:01 AM

Originally posted by philbaum

Just trying to learn :-)

What panoguy said, but I'll add an overlapping reason:

#3.1 When one of your "multiple lights" is the sun. It's hard to turn the sun off, and it can be hard to tell exactly what the flash is doing from the small screen and histogram that you're squinting at on a bright day, especially if it's hitting only a small portion of the frame.

and one that's related to #2, but I think different enough

#5 Accuracy - meters are typically accurate down to a 1/10 of a stop, my ability to base an exposure off the camera's histogram is not quite as reliable. Fabulous when you're doing a series of images you'd like to be consistent over several sessions.

Class A · 06-27-2015, 03:16 AM

Originally posted by BrianR

Fabulous when you're doing a series of images you'd like to be consistent over several sessions.

If consistency is the goal then manual mode for the camera and flashes is the way to go.

In terms of accuracy, given the noise levels of today's sensors, you can be a stop off and will get away with it easily. No need to hit the "correct" exposure by 1/10 of a stop at all. And, again, what is the "correct" exposure? The light meter does not know and it won't help you to avoid overexposure in areas you did not meter for.

BrianR · 06-27-2015, 02:23 PM

Originally posted by Class A

If consistency is the goal then manual mode for the camera and flashes is the way to go.

Of course... manual flash and camera settings kinda go hand in hand with a light meter don't they? I'm talking about using the same lighting setup I used yesterday, or a month ago, and matching the exposure.

Originally posted by Class A

In terms of accuracy, given the noise levels of today's sensors, you can be a stop off and will get away with it easily. No need to hit the "correct" exposure by 1/10 of a stop at all. And, again, what is the "correct" exposure? The light meter does not know and it won't help you to avoid overexposure in areas you did not meter for.

Of course you have some room to be off, but IMO it's much easier to process a bunch of images if they are all off by the same amount. I'm considering 'accuracy' here as in 'able to match my exposure from last time'. I'm in no way claiming there is some universal 'correct' exposure and I'm sorry if I gave that impression (I tried to be careful and use the word 'consistent' and not 'correct').

philbaum · 06-27-2015, 06:09 PM

Originally posted by glee46

So I went with the L758DR. I have a lot of manual lenses, and the difference in the time it takes and the results are worlds apart. Even with my Pentax 14mm 2.8 on my K-5 the difference in exposures make a huge difference as well. Right now, when I shoot outdoors with 4 flashes, (All on V6's with a V6 on TX to control them all) and a reflector, this light meter, and the V6, has given me control over picture outcome and time.

I'd be interested to see a shot of what you're working on?? Totally puzzled as to what might require 4 flashes and a reflector. If you'd rather not - i understand as well.

---------- Post added 06-27-15 at 06:16 PM ----------

This is an example of a recent promo shot for a new play. The theatre program developer cropped off the top of it, blew it up to 8 1/2 x11 color and used it for the opening page of the program. Looked gorgeous - even if i say so myself. The problem i had taking the picture was not with the exposure settings but putting the flash and actors in a position where the bar shadows would not cover their faces :-( The play was a comic murder mystery called the "The Mystery of Irma Vep" - written in the 80's and still funny.

[IMG]

[/IMG]

glee46 · 06-28-2015, 01:23 AM

Originally posted by philbaum

I'd be interested to see a shot of what you're working on?? Totally puzzled as to what might require 4 flashes and a reflector. If you'd rather not - i understand as well.]

I live in a complex that has a Mediterranean look with columns, and gardens. I shoot at night, so I'm using the flashes for effect and the reflector to bounce onto my model. As soon as I get something that really catches the whole look I'm trying to achieve, I'll be sure to post them.

06-27-2015, 01:08 AM	#10
glee46 Veteran Member Join Date: Nov 2010 Location: North of San Francisco, California Photos: Gallery \| Albums Posts: 598 Original Poster	I Went With The L758DR So I went with the L758DR. I have a lot of manual lenses, and the difference in the time it takes and the results are worlds apart. Even with my Pentax 14mm 2.8 on my K-5 the difference in exposures make a huge difference as well. Right now, when I shoot outdoors with 4 flashes, (All on V6's with a V6 on TX to control them all) and a reflector, this light meter, and the V6, has given me control over picture outcome and time.

06-27-2015, 06:09 PM	#14
philbaum Veteran Member Join Date: Oct 2007 Location: Port Townsend, Washington State, USA Posts: 3,659	Originally posted by glee46 So I went with the L758DR. I have a lot of manual lenses, and the difference in the time it takes and the results are worlds apart. Even with my Pentax 14mm 2.8 on my K-5 the difference in exposures make a huge difference as well. Right now, when I shoot outdoors with 4 flashes, (All on V6's with a V6 on TX to control them all) and a reflector, this light meter, and the V6, has given me control over picture outcome and time. I'd be interested to see a shot of what you're working on?? Totally puzzled as to what might require 4 flashes and a reflector. If you'd rather not - i understand as well. ---------- Post added 06-27-15 at 06:16 PM ---------- This is an example of a recent promo shot for a new play. The theatre program developer cropped off the top of it, blew it up to 8 1/2 x11 color and used it for the opening page of the program. Looked gorgeous - even if i say so myself. The problem i had taking the picture was not with the exposure settings but putting the flash and actors in a position where the bar shadows would not cover their faces :-( The play was a comic murder mystery called the "The Mystery of Irma Vep" - written in the 80's and still funny. [IMG][/IMG]

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Cactus RF60 & V6 Bundle $174	Roob-N-Boots	Pentax Price Watch	32	04-21-2015 09:40 PM
cactus v6 info	Murfy	Flashes, Lighting, and Studio	6	01-31-2015 09:10 AM
external light meter?	pixxie	Pentax DSLR Discussion	13	11-25-2014 09:59 PM
Cactus V6	Storm Chaser	Troubleshooting and Beginner Help	7	10-16-2014 11:04 PM
Cactus v6 help	dogzilla	Flashes, Lighting, and Studio	13	05-26-2014 10:57 PM

06-19-2015, 01:18 PM	#1
glee46 Veteran Member Join Date: Nov 2010 Location: North of San Francisco, California Photos: Gallery \| Albums Posts: 598	Cactus V6 & External Light Meter? I know that Sekonic has a build in RX for Pocket Wizard. I jumped on board with 6 Cactus V6 and 4 flashes, thinking it would work with them. Are there any light meters anyone would recommend to work with the V6? Or, is there a work around to get the Sekonic to work with the Cactus?

06-19-2015, 01:44 PM - 1 Like	#2
panoguy Pentaxian Join Date: Sep 2007 Location: Washington, D.C. Photos: Gallery \| Albums Posts: 3,327	Set your Sekonic's measuring mode to "Flash - cordless." The meter will then wait up to 90 seconds for a flash (dramatic increase in brightness) to measure the light. Just press the button on front of the V6 to trigger your flashes. Some Sekonics even have a "Flash - multiple" to measure cumulative effects, so you can move yourself out of the way if you're blocking a light, just by putting the flashes on different V6 channels and triggering them sequentially. If you need a more responsive solution, Cactus makes a tiny little PC sync to 3.5mm phono cord that plugs into the V6 and then into the PC port on the light meter. Then you change the measuring mode to "Cord - PC" mode and the meter will trigger the flash, just like the PWiz, but with a dangly bit.

06-19-2015, 05:43 PM	#3
glee46 Veteran Member Join Date: Nov 2010 Location: North of San Francisco, California Photos: Gallery \| Albums Posts: 598 Original Poster	Originally posted by panoguy Set your Sekonic's measuring mode to "Flash - cordless." The meter will then wait up to 90 seconds for a flash (dramatic increase in brightness) to measure the light. Just press the button on front of the V6 to trigger your flashes. Some Sekonics even have a "Flash - multiple" to measure cumulative effects, so you can move yourself out of the way if you're blocking a light, just by putting the flashes on different V6 channels and triggering them sequentially. If you need a more responsive solution, Cactus makes a tiny little PC sync to 3.5mm phono cord that plugs into the V6 and then into the PC port on the light meter. Then you change the measuring mode to "Cord - PC" mode and the meter will trigger the flash, just like the PWiz, but with a dangly bit. Thanks Panoguy. I had a feeling there was a way to get it to work. I have the PC sync with an extra V6 to control the flash and shutter. I just wanted to make sure it worked before I dropped some big bucks on the Sekonic.

06-20-2015, 06:48 PM	#4
panoguy Pentaxian Join Date: Sep 2007 Location: Washington, D.C. Photos: Gallery \| Albums Posts: 3,327	Originally posted by glee46 Thanks Panoguy. I had a feeling there was a way to get it to work. I have the PC sync with an extra V6 to control the flash and shutter. I just wanted to make sure it worked before I dropped some big bucks on the Sekonic. I'm using a Sekonic L478DR meter (even though I don't use PW's), and like all Sekonics it is expensive but full-featured and very accurate. It's also easy to understand; no tiny, cryptic display- just a big iPhone-like touchscreen. The only issue I have is that the touchscreen isn't very "touchy." Sometimes it takes a number of pokes or swipes to get it to respond. Good thing the meter button is a physical one!

06-21-2015, 09:40 AM	#5
glee46 Veteran Member Join Date: Nov 2010 Location: North of San Francisco, California Photos: Gallery \| Albums Posts: 598 Original Poster	Originally posted by panoguy I'm using a Sekonic L478DR meter (even though I don't use PW's), and like all Sekonics it is expensive but full-featured and very accurate. It's also easy to understand; no tiny, cryptic display- just a big iPhone-like touchscreen. The only issue I have is that the touchscreen isn't very "touchy." Sometimes it takes a number of pokes or swipes to get it to respond. Good thing the meter button is a physical one! I'm torn between the L478DR and the L758DR. They have a a model L758D, without the PW controller in it, but it only sells in Europe. I guess I'm holding out that they might come up with a controller for the Cactus V6. It also seems that to get the profile of camera and lenses, one has to shell out another $100. Sort of a rip off. It would be nice if Cactus came out with a light meter which works with all. The price would come down, and it would be a big win for us all.

06-26-2015, 11:20 AM	#6
philbaum Veteran Member Join Date: Oct 2007 Location: Port Townsend, Washington State, USA Posts: 3,659	Originally posted by glee46 I'm torn between the L478DR and the L758DR. They have a a model L758D, without the PW controller in it, but it only sells in Europe. I guess I'm holding out that they might come up with a controller for the Cactus V6. It also seems that to get the profile of camera and lenses, one has to shell out another $100. Sort of a rip off. It would be nice if Cactus came out with a light meter which works with all. The price would come down, and it would be a big win for us all. Okay, i'll ask the dumb question : Why would one need a light meter? DSLRs generally show the EV level in manual mode. Or just take a digital picture and adjust from there. I can see the need for light meters in the days of film where one doesn't have any immediate feedback. But in the days of digital camera - Why? Just trying to learn :-)

06-26-2015, 04:30 PM	#7
panoguy Pentaxian Join Date: Sep 2007 Location: Washington, D.C. Photos: Gallery \| Albums Posts: 3,327	Originally posted by philbaum Okay, i'll ask the dumb question : Why would one need a light meter? DSLRs generally show the EV level in manual mode. Or just take a digital picture and adjust from there. I can see the need for light meters in the days of film where one doesn't have any immediate feedback. But in the days of digital camera - Why? Just trying to learn :-) #1 reason (realistically): for pros, if you have a paying client under your strobes, they don't want to see you chimping and adjusting your lights after each flash, long before you start to direct them into pose. #2: camera meters are based on the light reflected from within the scene (so a black or white object will bias the meter), while incident light meters are based on light directed at the scene (colors and tones in the scene don't affect the light sources themselves). This gives consistency regardless of clothing choices and skin colors, and prevents the camera "thinking for you." #3: multiple lights and ratios - a meter can figure that out for you, while no camera can do that... only lots of experience behind it. #4: it looks really professional (no really, that's one of the reason people buy them!)

06-26-2015, 11:51 PM	#8
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by philbaum Why would one need a light meter? I agree with you that there is little motivation left to use an external light meter. Panoguy's point #3 is the best argument remaining: While a meter cannot figure anything out automatically, using an external light meter is the quickest way to establish certain lighting ratios for multiple light sources (e.g., 1:3:4). This still isn't a silver bullet, as the ratio of a hair kicker may need to be 1/3 instead 1/4 of the key light, depending on the subject's hair colour, but it helps to get a reasonable starting point. Having said that, often one will use one's lights in standard positions with standard distances to the subject and making the power settings manually from recorded notes is quicker than measuring the ratios again. Regarding #2 from Panoguy's list: Light meters typically support both reflectance and incident metering because there is a use for both. Incident metering can sometimes be replaced by using spot reflectance metering and, again, is not a silver bullet because most of the time photography is not about achieving technically accurate exposures, but expressing artistic intent with deliberate under- or over-exposure. Finally, I think points #1 and #4 are pretty much the same. With a bit of experience, obtaining the desired exposure without using a light meter does not take considerably longer. And if you want to really want to work professionally, you set up your lights with a test subject before the client comes into play anyhow.

06-27-2015, 12:09 AM	#9
philbaum Veteran Member Join Date: Oct 2007 Location: Port Townsend, Washington State, USA Posts: 3,659	@Panoguy @Class A, Thanks for the answers guys - food for thought :-)

06-27-2015, 03:01 AM	#11
BrianR Veteran Member Join Date: Dec 2010 Location: Ontario Photos: Gallery Posts: 3,332	Originally posted by philbaum Just trying to learn :-) What panoguy said, but I'll add an overlapping reason: #3.1 When one of your "multiple lights" is the sun. It's hard to turn the sun off, and it can be hard to tell exactly what the flash is doing from the small screen and histogram that you're squinting at on a bright day, especially if it's hitting only a small portion of the frame. and one that's related to #2, but I think different enough #5 Accuracy - meters are typically accurate down to a 1/10 of a stop, my ability to base an exposure off the camera's histogram is not quite as reliable. Fabulous when you're doing a series of images you'd like to be consistent over several sessions.

06-27-2015, 03:16 AM	#12
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by BrianR Fabulous when you're doing a series of images you'd like to be consistent over several sessions. If consistency is the goal then manual mode for the camera and flashes is the way to go. In terms of accuracy, given the noise levels of today's sensors, you can be a stop off and will get away with it easily. No need to hit the "correct" exposure by 1/10 of a stop at all. And, again, what is the "correct" exposure? The light meter does not know and it won't help you to avoid overexposure in areas you did not meter for.

06-27-2015, 02:23 PM	#13
BrianR Veteran Member Join Date: Dec 2010 Location: Ontario Photos: Gallery Posts: 3,332	Originally posted by Class A If consistency is the goal then manual mode for the camera and flashes is the way to go. Of course... manual flash and camera settings kinda go hand in hand with a light meter don't they? I'm talking about using the same lighting setup I used yesterday, or a month ago, and matching the exposure. Originally posted by Class A In terms of accuracy, given the noise levels of today's sensors, you can be a stop off and will get away with it easily. No need to hit the "correct" exposure by 1/10 of a stop at all. And, again, what is the "correct" exposure? The light meter does not know and it won't help you to avoid overexposure in areas you did not meter for. Of course you have some room to be off, but IMO it's much easier to process a bunch of images if they are all off by the same amount. I'm considering 'accuracy' here as in 'able to match my exposure from last time'. I'm in no way claiming there is some universal 'correct' exposure and I'm sorry if I gave that impression (I tried to be careful and use the word 'consistent' and not 'correct').

06-28-2015, 01:23 AM	#15
glee46 Veteran Member Join Date: Nov 2010 Location: North of San Francisco, California Photos: Gallery \| Albums Posts: 598 Original Poster	Originally posted by philbaum I'd be interested to see a shot of what you're working on?? Totally puzzled as to what might require 4 flashes and a reflector. If you'd rather not - i understand as well.] I live in a complex that has a Mediterranean look with columns, and gardens. I shoot at night, so I'm using the flashes for effect and the reflector to bounce onto my model. As soon as I get something that really catches the whole look I'm trying to achieve, I'll be sure to post them.