[ekim89]

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Ok, so after doing much research and such about a cheap flash unit for my K-x, there are some questions that I need answered. I am looking at a Sunpak Auto 422D Thyristor or Sunpak Auto388. The more straightforward the answer, the better because my head is spinning from reading a whole bunch of information.

Here are my questions:

1) Is it safe to use on my K-x DSLR, and does anyone happen to know the max. allowable voltage range that can be used on the K-x? (I understand that I would need to test the voltage of the flash to be safe and I read the Botzilla Photo Strobe Trigger Voltages for both the Auto388 and 422D)

2) This whole module/hotshoe business, which one will work and what should I look for when buying on eBay?
I noticed my search on eBay returned things such as "Nikon with Nikon NE-2D head"

3) In the picture at the bottom of this listing, the module on there says for CONTAX 137MD/139 QUARTZ MODULE and all other hot shoe mount regular cameras, would that mount work for the K-x?

4) Will the flash unit allow me to use a radio trigger?

If you can, please help the newbie that doesn't understand the aspects of flashes and if given a choice between the 422D and Auto388, which would you choose and why? Thank you!

[SOldBear]

Ok, so after doing much research and such about a cheap flash unit for my K-x, there are some questions that I need answered. I am looking at a Sunpak Auto 422D Thyristor or Sunpak Auto388. The more straightforward the answer, the better because my head is spinning from reading a whole bunch of information.

Among the "old" flash units, the Sunpak 4xxD series offers the most bang the buck. They are compact, powerful (for their sizes), can swivel and bounce, have auto mode with 3 settings, have manual mode with variable ratio settings, and probably most importantly, have low trigger voltage.

I'm not familiar with the Sunpak 388, but I think it is one step below the 4xxD series. I think the biggest disadvantage of the 3xx series compared to the 4xxD is that the 3xx series does not have "dedicated" module. The "dedication" really does not matter for the current DSLRs, but the removable module (with the light sensor) gives you some flexibility in using the flash off camera (more on this later).

1) Is it safe to use on my K-x DSLR, and does anyone happen to know the max. allowable voltage range that can be used on the K-x? (I understand that I would need to test the voltage of the flash to be safe and I read the Botzilla Photo Strobe Trigger Voltages for both the Auto388 and 422D)

You will NOT find the specs of allowable trigger voltage from Pentax, or any other camera makers (except Ricoh specifically says 20V in the manual). I use 24V as the limit.

The 4xxD series has trigger voltage around 6 - 7V so it is safe for Pentax DSLRs.

2) This whole module/hotshoe business, which one will work and what should I look for when buying on eBay?
I noticed my search on eBay returned things such as "Nikon with Nikon NE-2D head"

If the module has the standard foot that fits in the camera's hotshoe, you're OK. Except for the sync signal (for which all modules are the same), there is no communication between the flash and the camera. I have several different modules: for Ricoh, for Nikon (yes, the NE-2D), for Pentax, and for Minolta. I use them exchangeably for my K10Ds and K7, even with my Canon G5 and Ricoh GX200 without any problem.

When the camera is in Av mode (maybe in some other modes as well), the Pentax modules (PT-1D and PT-2D) will set the camera's to sync speed (normally around 1/60 sec depending on the lens). I myself don't use this feature. I just set the camera in M mode and choose the shutter speed myself.

The only modules you want to avoid are the ones that fit on top of the rewind crank for Nikon and for Olympus. They don't have the standard foot and thus don't fit the camera's hotshoe. But if the flash comes with it, it's OK. You can buy modules separately (e.g. from KEH).

3) In the picture at the bottom of this listing, the module on there says for CONTAX 137MD/139 QUARTZ MODULE and all other hot shoe mount regular cameras, would that mount work for the K-x?

Yes. It will work with your K-x. I would buy that particular one if I needed a flash right now.

4) Will the flash unit allow me to use a radio trigger?

Yes. Sunpak flashes work fine with my Yongnuo RF-602.

If you can, please help the newbie that doesn't understand the aspects of flashes and if given a choice between the 422D and Auto388, which would you choose and why? Thank you!

As stated, I don't know much about the 388. But I'd choose the 422D. Here's the reason:

You can buy Sunpak dedicated extension cord (I have the EXT-08, about $10 from KEH). The extension cord will be between the module (which is attached to the camera's hotshoe) and the flash unit. No matter where you point the flash, the light sensor always faces forward. This is helpful in many situations.

Here are some photos of my DX36 setup (DX36 is the European name of 444D, which is very similar to the 422D):

[Ira]

How do you test voltage?

Connect the voltmeter (voltometer?) to the hot shoe or module and fire a discharge?

[ekim89]

Thank you very much SOldBear! That were the exact answers I was looking for! I will go ahead from there and most likely purchase the flash. Ira, I'm not 100% sure how to test the voltage and I need to research that more.

[Ira]

Thank you very much SOldBear! That were the exact answers I was looking for! I will go ahead from there and most likely purchase the flash. Ira, I'm not 100% sure how to test the voltage and I need to research that more.

Have you been here yet? Scroll down--it's "kind of" a list of all the voltages!

Photo Strobe Trigger Voltages

The problem is that not only do certain flashes vary slightly on each discharge, they can vary by hundreds of volts within the same model built a year apart!

In addition, there's still debate about whether you can go 100% safely up 20V on a KX, while the consensus of users is you should shoot for 6 and under, with 9 being fine.

There are plenty of flashes that meet the totally safe criteria as determined by this list, but the ones that I'm hunting for on eBay are mostly questionable, and listed as "Your Call"--meaning it's your decision to make whether it's 100% safe. So, regardless of the list, you still have to test your particular unit and see what the deal is.

I know that the SunPak555 is safe as explained by a member here, but the list still describes it as "Your Call."

I'm bidding on a 611 right now, which is described the same way--except that older models can trigger as high as 190! But if I can get it cheap, I'll take the chance...test it...and if necessary, get the SafeSync model. I like playing around with the old stuff anyway, so once you have the SafeSync, you can safely use any piece of crap on it.

I just have to learn how the heck you test it.

[ekim89]

Yeah, I was afraid about the varying voltages, so I am going to get a radio transmitter and use the flash wireless until I can get a SafeSync. I am also hoping to find a definitive tutorial on how to test the voltage for myself. I saw that site for the Photo Strobe Trigger Voltages and noticed the 422D said "your call," so I will definitely test it if I get the flash and let you know how it went. Thanks again!
Mike

[SOldBear]

To measure the trigger voltage of a flash, use a volt meter or a multi-meter. Something like this costs only a few $ and is useful for other things around the house.

Let the flash charged up (ready pilot light on).

Set the multi-meter to measure VDC, range 1000V (if the multi-meter is not auto-range), negative probe to a terminal on the side of the flash's foot (green arrow), positive probe to the center pin of the flash's foot (red arrow).

The reading on the multi-meter is the trigger voltage. If you don't have a reading, or if the reading is low, change the setting on the multi-meter to a lower range.



About the Sunpak 611: it's very likely that the trigger voltage is high. Read this thread for a DIY SafeSync for cheap. That was the very first voltage reducer I've assembled. I didn't say in the thread, but I was able to stuff the voltage reducer in the 611 remote sensor. Later, I did similar things to several Sunpak 522 and Metz CT45-1 units.

My Metz CT45-4 has trigger voltage of 24V. I've been using it for a while with my K10D. I've had no problem.

Here's one of my Metz CT45-1 units with Mecamat remote sensor. The voltage reducing circuit is inside the Mecamat. The original trigger voltage is 230V, which is reduced to 7.5V.

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Last edited by SOldBear; 12-08-2010 at 01:30 PM.

[ekim89]

Thank you very much for another very informative post! I should have no problem following those directions for testing the firing voltage

[Ira]

To measure the trigger voltage of a flash, use a volt meter or a multi-meter. Something like this costs only a few $ and is useful for other things around the house.

Let the flash charged up (ready pilot light on).

Set the multi-meter to measure VDC, range 1000V (if the multi-meter is not auto-range), negative probe to a terminal on the side of the flash's foot (green arrow), positive probe to the center pin of the flash's foot (red arrow).

The reading on the multi-meter is the trigger voltage. If you don't have a reading, or if the reading is low, change the setting on the multi-meter to a lower range.



About the Sunpak 611: it's very likely that the trigger voltage is high. Read this thread for a DIY SafeSync for cheap. That was the very first voltage reducer I've assembled. I didn't say in the thread, but I was able to stuff the voltage reducer in the 611 remote sensor. Later, I did similar things to several Sunpak 522 and Metz CT45-1 units.

My Metz CT45-4 has trigger voltage of 24V. I've been using it for a while with my K10D. I've had no problem.

Here's one of my Metz CT45-1 units with Mecamat remote sensor. The voltage reducing circuit is inside the Mecamat. The original trigger voltage is 230V, which is reduced to 7.5V.

Wow! Thanks for the time and explanations!

So on a 611, you're testing it via the sensor, correct? And if you buy a flash that only has a sync cord, you have to buy a hot shoe adapter, correct? And test it the same way? And ever actually trigger it?

Just get the reading while it's ready to fire?

[SOldBear]

Wow! Thanks for the time and explanations!

You're very welcome.

So on a 611, you're testing it via the sensor, correct? And if you buy a flash that only has a sync cord, you have to buy a hot shoe adapter, correct? And test it the same way? And ever actually trigger it?

Actually, when I got the 611, I didn't have the remote sensor. I bought the sensor much later. My 611 came with a sync cord. I didn't have a hot shoe adapter, so I modified one of the cheapo optical slave units into a PC terminal - hot shoe adapter and used it to help with measuring the voltage. Measuring the voltage at the end of the PC terminal is possible (the center contact is positive, the outer ring is negative), but it's very easy to trigger the flash (no harm, just try measuring again).

Interestingly, the trigger voltage at the PC terminal and at the foot of the remote sensor can be significantly different. On one of the Sunpak 522 units, the voltage at the PC terminal is 180V and the voltage at the foot of the remote sensor is 10.5V.

Just get the reading while it's ready to fire?

That's correct.

[ekim89]

Hey there Ira and SOldBear, I just received the Sunpak 422D as a Christmas gift and I measured the trigger voltage to be 11.2 volts DC with a YC-1D module on it. I cannot wait to try it out. On a side note, I got a Lowepro backpack camera bag and circular polarizer! Merry Christmas!

[Ira]

I just tested my "new" Sunpak 555 with the module in the hot shoe and two different cords:

She wouldn't fire at all with the first cord, and with the second cord, nothing for a few shots....then she did fire a few times...and then nothing again.

I PM'd Bear, so maybe he can point me in the right direction to troubleshoot this.

Christmas--bah humbug!

I've had everything since last week, but waited until today to play with it.

.

[Ira]

Flash problems will wait:

Christmas prime rib dinner first!

[SOldBear]

I just tested my "new" Sunpak 555 with the module in the hot shoe and two different cords:

She wouldn't fire at all with the first cord, and with the second cord, nothing for a few shots....then she did fire a few times...and then nothing again.

Hope you had a great Christmas, Ira, notwithstanding the problem with the 'new' toy.

For now, let assume that there is only one cause of the problem.

The flash fires consistently with the PC connection, so I think the flash unit itself is OK.

Since it happens with both of the cords (albeit intermittently with one), the more probable cause is the module.

Do you have another Sunpak module you can test? If not, and if you don't want to buy one now (I don't want to pay $10 for a $3 item either), I can let you use one of mine. Of course it'll take a few days in the mail.

BTW, I used this set up for about 100 photos during a Thanksgiving dinner. I got perfect exposure every time:



Here's a close-up of the module; you can see how far it goes into the K7's hotshoe:

[Ira]

As you know by now, I PM'd you.

Still waiting to hear from KEH, and maybe they'll try to rectify the issue by sending me another module to test.

I'm not too optimistic though, since I emailed them yesterday, and I've yet to receive a reply from them--even one just acknowledging receipt of my email.