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Old Mar 1, 2007, 7:18 AM   #21
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To each their own... $50 is cheaper than some thyristor flashes, I think it's at least worth a try... considering your next option is $100 more.

-Nick
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Old Mar 1, 2007, 4:50 PM   #22
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When I asked the "expert" about this flash from Promaster, he said there will be a problem with the contacts with the newer DSLR cameras and should not be used because it would damage the camera and flash. I was disappointed with that response and decided not to purchase the flash.
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Old Mar 2, 2007, 12:31 AM   #23
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Well if thats the case, of just contact damage that is easy to spot and IF it does actually start then I will stop.... and big deal $35 wasted but lots of shots.

My guess, reallity might be a contact corrosion issue (likely on the flash side) Keep the camera and flash contacts clean and shiny there should be no arcing/heat related damage.

Pehaps the DX models just have gold or other non corroding plated contacts.

And depending on the two different metals (flash and what Pentax uses for the contact could even be an electrochemical reaction.... but again just paying attention and keeping things clean that likely wouldn't happen.

But that still shouldn't be that much problem the friction of mounting and dismounting it.... but maybe for those who like never take the flash off.... especially if in a damp/humid/salty environment.

BTW did "expert" say the 7500DX would be OK, because according to their site, they still don't make a Pentax version of that. (at least not on the product page)
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Old Mar 2, 2007, 12:48 AM   #24
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snostorm wrote:
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Hi Heyward,

I stand corrected. It's pretty strange that Promaster doesn't credit this feature in its specs. P-TTL's been around since 2001, so it's entirely possible that they had this feature.

I wonder what other undocumented features they might have missed in their spec sheet?

Scott
Oh and after the other flash thread resurfacing..... furter proof the PM 7000M is P-TTL.....comfirm ed....my dirt cheap, tiny but suprising bright little pocket Quantaray SLAVE flashes are now useless as they will trigger on the preflash :?

Its too Bad the K10D doesn't offer a plain TTL option inits firmware.

Maybe I'l have to write Pentax as suggestion for the next firmware update... might not take all that long....that first one came out just after release... likely generated from beta testers.

Hopefully Pentax keeps listening to user feedback and continues regular development.... at least until they come out with better hardware (new/better model).
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Old Mar 2, 2007, 1:55 PM   #25
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Hayward wrote:
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Its too Bad the K10D doesn't offer a plain TTL option inits firmware.

Maybe I'l have to write Pentax as suggestion for the next firmware update... might not take all that long....that first one came out just after release... likely generated from beta testers.

Hopefully Pentax keeps listening to user feedback and continues regular development.... at least until they come out with better hardware (new/better model).
Hi Hayward,

TTL compatibility is not a firmware thing. It requires a separate sensor in the lightbox aimed at the sensor that reads the reflected light during the exposure. Only the D, DS, and DS2 had them, the rest of the Pentax DSLRs don't.

Scott
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Old Mar 3, 2007, 12:58 AM   #26
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So in P-TTL what is the on/in camera sensor looking at and where is it?
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Old Mar 3, 2007, 2:38 AM   #27
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Hi Hayward,

In P-TTL, the normal exposure sensor in the pentaprism housing does double duty and meters the preflash (this happens while the mirror is still down -- reflecting the preflash lit scene up into the pentaprism), it then, IIRC, in less than @ 120 milliseconds meters the scene and communicates the correct (hopefully) intensity and duration information to the flash unit in time for the main flash which fires after the mirror flips up and exposes the main CCD.

There is also the sensor in the flash unit, which I believe also has a minor role with the controlling the exposure, maybe by cutting off the duration (my guess, at least). All in all, it's pretty sophisticated stuff --


BTW, here's a quick shot of the TTL sensor in my DS's light box:



It's recessed in the side of the lightbox, normally behind the mirror (which is locked up at the left edge of the frame), pointed at the imaging CCD which would be at the bottom of the pic -- you can just see the upper corner --. This is why it doesn't need a preflash -- it's reading the reflection off the main CCD in real time, during the exposure.

The difference in the reflectivity between film and the CCD of a digital camera is the usually stated reason why all the mfgs are moving towards preflash, but I have to think that cost and the opportunity to sell new flash units might have something to do with this also. On the other hand, the main exposure sensor has to be considerably more sophisticated than a TTL sensor, so P-TTL has much more potential for exposure accuracy down the road. I think that Pentax has done some recent tweaking of way the camera controls the flash, which is why the older Sigma flashes have to be rechipped. Only the D, the DS, and the DS2 have these TTL flash sensors among the Pentax DSLRs.

Scott


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Old Mar 3, 2007, 3:35 AM   #28
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Well once again you got me curious.....

Putting the K10D in Manual does not help still P-TTL preflash (Internal Flash)

However there is a solution for using those old Quantaray mini (or other plain TTL/manual) slaves.....

Put the 7000M FLASH in manual.... then it does not preflash.... this is not such a bad thing as likely if you are using slaves you are in a controled situation, where test shots are not a big issue to get exposure right... and good chance you'd be close anyways.... if you understand flash exposure.
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Old Mar 4, 2007, 5:21 PM   #29
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Here is the reply I got from Promaster when I asked about a strobe for my K100D

The Promaster FTD5950 is a great flash for 35mm cameras, but it was not
designed for the low sync voltage requirements or new ttl flash systems of
digital cameras. This flash will not work properly or safely with the Pentax K100D.
Promaster has a series of DX flash units and DX modules designed
specifically for the new TTL flash systems of digital cameras and their low
sync voltage requirements.
The FTD 5550DX is a bounce swivel flash (GN 100) that allows you
to bounce off a low white ceiling either horizontally or vertically. This
gives a much softer light in portrait situations and makes shadows
fall more naturally the way we are used to seeing them.
The FTD 5750DX adds a zoom head to acheive a guide# of 130
and adds a secondary fill flash to highlight under the eyes, nose and
chin when bouncing. This would be the digital compatible version of
your 5950.
These flash units use a removeable module like your FTD 5950 but
designed to fit only the DX flash units. For thePentax K100Dyou would need the #5432DX module for Pentax.
The 7500DX flash forPentax Digital cameras adds a motorized zoom
head that automatically zooms as you zoom your lens, to maximize
distance when in telephoto and give the proper angle of coverage
as you zoom back for a wide angle shot. Other features include multi
strobe flash, rear curtain sync, and an illuminated panel so you can see
your flash range and other settings at night.
The 7500DX does not use the removeable module system so
you would just buy a 7500DX version for Pentax #6335. One thing that I have found with Pentax digital SLR cameras is that if the batteries in the camera are low the camera and flash will begin to fire out of sync. So make sure you keep spare batteries on hand. Flashexpert

Mark
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Old Mar 5, 2007, 1:33 AM   #30
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mandelm wrote:
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This flash will not work properly

or safely with the Pentax K100D.
Now these are the two separate phrases that really make me wonder (YET IN A SINGLE SENTENCE).... how honest (vs just sellling new more expensive/not discounted or used flashes) Promaster is being.

The "This flash will not work properly" because in the case of the Promaster 7000M on the K10Dis TOTAL BS... actually it works VERY well IF NOT PERFECTLY...INCLUDING p-ttl SUPPORT..

And it is always the same "form" response that gets posted... probably for anyone with ANY Digital camera.

Now the upper end lightweight (in many ways) P&S some of which have hot shoes... could believe it.... but I would be very surprised if the flash actually produces any voltage/current that would be damaging to a DSLR (basically a transposed film SLR's) when from C. N, and Pentax... and oh yeah Sony/Minolta.
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