Author Topic: Flash incompatibility  (Read 7803 times)

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Offline Stäck

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Flash incompatibility
« on: November 29, 2004, 11:16:02 AM »
Not only is the Dynax 7D incompatible with all older flashes (as I've already been whining about in this thread).
As could be read in the specs from Konica-Minolta, the 7D can do ADI only with "D" lenses and flashes (it's some kind of more advanced TTL flash metering). It turns out that if you don't have a D lens, it can't even do normal TTL flash metering, instead the camera falls back to "pre-flash TTL". From the few pictures I've taken, it seems to me that this flash metering is pretty unreliable. I was using the built-in flash and Sigma 28/1.8 and Tokina 19-35/3.5-4.5 lenses, at ranges from 1-5 meters. I took about 10 pictures, and 4 of them were very badly exposed (3 over and 1 under). It's also a very annoying flash mode, since the first flash (metering) causes people to close their eyes just in time for the second flash (exposure).

It's quite easy to tell if the camera uses this mode, since the first flash can be seen in the viewfinder as it is fired before the mirror moves up. In "normal" (or in this cameras case, ADI) TTL flash mode, the flash (or the second "exposure" flash in pre-flash mode) cannot be seen, since the mirror is upp (and the viewfinder is totally black).

I usually don't like having to use a flash, but in some cases it is the only way to get a good picture. But not only do I have to get a new flash (if I want to have something else than the itsy-bitsy-built-in one), but it will only work properly with "D" lenses, meaning most older and/or non-Minolta lenses are out. I can probably live without it (high ISO and anti-shake usually helps), but people who are dependent of good flashes should know that they might need a new bunch of expensive hardware.

I'll try to quit whining now. Really, apart from this flash issue, I couldn't be more happy with my new camera.

Offline gazraa

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Flash incompatibility
« Reply #1 on: November 29, 2004, 01:39:36 PM »
thanks for the info. I hope that there aren't going to be any other 'surprises' that get found out after some use.

good surprises are ok though, it's the ones that mean we'll have to spend more money on replacing exisiting kit for new kit that I don't want.
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Offline alane

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Flash & Lens compatibility
« Reply #2 on: November 29, 2004, 02:14:35 PM »
I have a 3600HS (D) and a Tamron 28-300 xi superzoom lens.

I was taking some shots last night using the Wireless flash option and the pictures appear to be slightly overexposed. I also used a Pentax (sorry) mini slave flash unit so this might be the casue of the overexposure I'll have to run some more tests.

Offline Stäck

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Flash incompatibility
« Reply #3 on: November 29, 2004, 04:22:36 PM »
alane, your flash supports ADI, but the lens (most probably) doesn't. If wireless flashes don't work with preflash-TTL, it might be that it reverts to manual mode, in which case you have to set flash exposures yourself.

Offline Stäck

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Flash incompatibility
« Reply #4 on: December 10, 2004, 09:25:43 AM »
I guess I'll have to take back some of my gripes.
I just read through the manual regarding flash modes, and it says that the ADI flash mode also does a pre-flash for measuring. I tested with my only "D"-lens (the bundled cheapo 28-100 which I haven't put on the body since I got my 19-35), and it indeed fires of a pre-flash as well. This leads me to believe that the difference between ADI and "normal pre-flash TTL" isn't very much. It probably just fires preflashes of different power for different focusing distances.
I also took a few test shots (including shooting myself in the eye from 2 feet...), and the time between pre-flash and exposure is probably too small to worry about (seems to me like less than 1/10th of a second). Unless you're paying attention, it looks just like one flash, and I don't think it's enough time for people to close their eyes.

Has anyone tested the 7D with any non-Minolta flashes? The ones I'm interested in are the Sigma EF500 DG Super and the Metz 54 AF-1. Both are about as powerful as the Minolta 5600HS(D), but way cheaper.
The Metz can do ADI (for whatever that's worth), but not high-speed sync. The Sigma is a little vague on details with the 7D, but normally it can do "everything". It seems it has very different compatibility with different cameras, and I would sure like to know what it can do with the 7D (such as high-speed sync, rear-curtain sync, wireless mode).

Offline tiny3d

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Other digital SLR's?
« Reply #5 on: March 17, 2005, 11:32:00 AM »
What is the status of real TTL support on other brands digital SLR's? Do they have the same issue with broken backwards compatability and no support for true TTL due to reflection issues of the sensor etc.

I have never heard mention of this problem before encountering it myself and then finding mention of it on various forums such as this one.

I guess all reviewers always get brand new equipment and would thus miss an issue like this...

The wireless flash system is one of the really nice things and not having TTL breaks most of it....

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Flash incompatibility
« Reply #6 on: March 17, 2005, 12:49:59 PM »
Quote from: Stäck


Has anyone tested the 7D with any non-Minolta flashes? The ones I'm interested in are the Sigma EF500 DG Super and the Metz 54 AF-1. Both are about as powerful as the Minolta 5600HS(D), but way cheaper.
The Metz can do ADI (for whatever that's worth), but not high-speed sync. The Sigma is a little vague on details with the 7D, but normally it can do "everything". It seems it has very different compatibility with different cameras, and I would sure like to know what it can do with the 7D (such as high-speed sync, rear-curtain sync, wireless mode).



I order the sigma under the advice from a sigma rep that it will work with my D7D.................. It didn't ...................... latter a found out from a tech at sigma that the firm ware only works up to A2 (in the newest sigma flash) but they are working on it :(

Offline Stäck

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Re: Other digital SLR's?
« Reply #7 on: March 18, 2005, 04:09:27 PM »
Quote from: tiny3d
What is the status of real TTL support on other brands digital SLR's? Do they have the same issue with broken backwards compatability and no support for true TTL due to reflection issues of the sensor etc.

I have never heard mention of this problem before encountering it myself and then finding mention of it on various forums such as this one.

I guess all reviewers always get brand new equipment and would thus miss an issue like this...

The wireless flash system is one of the really nice things and not having TTL breaks most of it....


My guess is that since both Nikon and Canon have had DSLR:s for a while, their (and other manufacturers) flashes already have supported the new flash modes for some time. They probably had the same backwards compatibility issues a couple of years ago, but chances are that someone who just got a ~?10000 camera won't fuss too much over having to buy a ?300 flash. And of course, if the manufacturers give out "official review hardware", they always make sure to send a set of fresh accessories as well.

As far as the third-party manufacturers (Sigma, Metz, Soligor) go, I think anything except Nikon and Canon is quite a small piece of their overall market, and they probably have fairly limited R&D resources. Therefore they focus primarily on having the newest features there, and the rest of the brands (Minolta, Olympus, Pentax) are secondary.

Offline tiny3d

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Re: Other digital SLR's?
« Reply #8 on: March 21, 2005, 09:12:46 PM »
Quote from: Stäck
They probably had the same backwards compatibility issues a couple of years ago, but chances are that someone who just got a ~?10000 camera won't fuss too much over having to buy a ?300 flash. And of course, if the manufacturers give out "official review hardware", they always make sure to send a set of fresh accessories as well.


Today I browsed the Canon EOS 20D manual and took the chance to lookup what they say about Flash usage. What I found was that they definately have the same issues about not having TTL functionality.

The EOS 20D manual says the following:
"The flash cannot be fired with an EZ-, E-, EG-, ML- or TL-series Speedlite set in the TTL or A-TTL autoflash mode. Use the Speedlite's manual flash mode instead if provided."

I haven't investigated things in more detail, but I already feel a bit better knowing that it's a general issue and not a minolta issue.

It was really surprised that even though reading extensively about the camera before purchase, I've seen no mention of the flash compatability issues, but as you say it's likely caused by the fact that reviewers usually get a "set" of fresh equipment for testing.

One feature that is available on Canons digital SLR's is FE (Flash Exposure) Lock. I haven't found this on the Dynax 7d yet. Is it available? With it, it should be possible to lock exposure even with older flash units since they have time to recharge before the final exposure. Same goes with wireless control etc.

Offline Stäck

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Flash incompatibility
« Reply #9 on: March 21, 2005, 11:11:03 PM »
As far as I know, it's the same issue with all DSLR:s. Normal TTL (with film cameras) uses light bounced off the film, usually with a sensor in the bottom of the film chamber. The sensor in a digital camera reflects light differently. It acts more like a mirror, reflecting light back at the lens. This means you can't have an efficient sensor without being in the way of the light. Therefore, DSLR:s employ different variants of a pre-flash. It's measured through the lens (so it is some kind of TTL), but it requires different capabilites of the flashes. For one thing, the flash has to be able to deliver two flashes in a close period of time (about 1/10th of a second). Second, and more importantly, the flash has to control its output differently. Instead of "just flash and I'll tell you when it's enough", the flash has to do first a pre-flash at some known power, and then when the camera says so, "do a flash that's 1.4x the power of the last one". It requires a completely different communication protocol, and more precise controlling electronics (being able to fire flashes with consistent, known power).

However, the more I use my camera, the less I feel the need for an external flash. High sensitivity, AS, a couple of f/1.8 primes, and the internal flash, together mean that I've never really felt that a more powerful flash has been necessary so far. Also, in most indoor situations I really don't want to use a flash anyway.