HV Battery for Honeywell Strobonar 882

[BeBu Lamar]

Again: consistent, so useful.

 

And again: GNs cannot be valid in most photographic situations. The only one in which they would be, you agree they are not valid either.

So again: they are good for comparisons. So stop complaining about they not being valid in another context. They can never be.

I am complaining because the manufacturers intentionally inflate their GN. It's not manufacturing variation or something out of their control. They know their flashes don't put out as much light as the GN suggested.

[q.g._de_bakker]

I am complaining because the manufacturers intentionally inflate their GN. It's not manufacturing variation or something out of their control. They know their flashes don't put out as much light as the GN suggested.

Yes. But whatever they say, the GN is of no practical use. So what?

[BeBu Lamar]

Yes. But whatever they say, the GN is of no practical use. So what?

So they cheat. That's what I am complaining about not because the GN is of no use but because in fact I would pretty much know what GN it actually is.

It's not like you buy 1 lbs of something and you may get more or less than 1 lbs. It's like you know if you buy 1 lbs you almost sure to get 1/2 lbs.

[Gary Naka]

So they cheat. That's what I am complaining about not because the GN is of no use but because in fact I would pretty much know what GN it actually is.

It's not like you buy 1 lbs of something and you may get more or less than 1 lbs. It's like you know if you buy 1 lbs you almost sure to get 1/2 lbs.

 

You are missing the point.

GN is based on testing in a standardized environment, whatever that may be, and however unrealistic you may think it is.

Exposure in the camera depends on the environment that the flash is in.

 

Inside my house, the GN exposure might be right on.

But outside the house in the back yard, the GN exposure will be one stop low. This is because there is no walls and ceiling to reflect the light back onto the subject.

Take the flash back into the house, and the GN exposure will be right on.

 

Even inside, the GN exposure might be different.

If I go to my friend home with a large room, high ceiling and dark walls and floors, there is less light reflected back to the subject, and the GN exposure would be less than my home with smaller rooms, an 8 ft ceiling and white walls and light floor.

With the SAME light output, the environment is changing the exposure.

 

If you shoot in a different environment, than the testing environment, the exposure WILL be different.

And if you shoot in different environments (home, office, church, banquet hall, etc.), the exposure will be different in each environment.

 

GN is an open loop concept. It is based on just the output of the flash, no consideration is given to the environment.

Automatic and TTL flashes use feedback to attempt to compensate for some of the environmental factors.

 

In your case, it seems that you are shooting in a larger/darker environment than the GN was determined in.

This does not mean the mfg is "cheating" it just means that your shooting and the testing environments are different, so that you cannot use the mfg GN. You have to adapt it to YOUR conditions.

[rodeo_joe1]

Inside my house, the GN exposure might be right on.

Try it. It won't be. Not unless you live in a gloss-white painted packing case.

 

If the "non-reflective environment" instruction stated in the standard was followed, then all other scenarios would require less exposure, not more.

 

Why so eager to defend the universal hyperbole of manufacturers?

Edited November 13, 2021 by rodeo_joe|1

[q.g._de_bakker]

Why so eagerly complain about the limited usefulness of something that never was meant to be more than it is?

[BeBu Lamar]

Why so eagerly complain about the limited usefulness of something that never was meant to be more than it is?

I think both Joe and I do not complain about the usefulness of the GN. We said the GN are always inflated and was done intentionally. A way to make a product seems better than what it is. If we during testing the GN and found they are greater than the manufacturers claim they are still not useful but we wouldn't complain about that. The fact that none of the flash I tested so far and I think Joe too would come up with a GN greater than claimed by the manufacturer.

[Gary Naka]

Try it. It won't be. Not unless you live in a gloss-white painted packing case.

 

If the "non-reflective environment" instruction stated in the standard was followed, then all other scenarios would require less exposure, not more.

 

Why so eager to defend the universal hyperbole of manufacturers?

 

Quote:

FWIW. The GN testing methodology described in the freely available Indian Standard (and probably lifted directly from the 'secret' ISO standard) specifies that measurement should take place in a "non-reflective room".

This wording is open to wide interpretation. It could mean anything from a matt black painted large hangar, to a small matt white painted wardrobe. Just as long as it didn't have a mirrored surface.

End quote

 

So what is the reference "non-reflective room?"

Absent any specifications and definition, as you say it could be anything from not mirrored to MATT BLACK with light absorbing panels, or a hanger.

Unless you have enough details of the measurement requirements, you cannot duplicate the test conditions. So you cannot evaluate how the test conditions compare to a real life environment.

 

What I am saying is that the exposure from the flash depends on the environment.

So if the GN is based on some representative "indoor" situation, you will not get the same exposure inside your house and outside in the backyard.

So if you primarily shoot outside, you WILL need more exposure, because there are no walls and ceiling to reflect the light back onto the subject.

 

And yes, IF the GN is based on near zero reflectance, then that is more representative of shooting outdoors.

So if you then go indoors, you will overexpose because of the light reflected back from the walls and ceiling.

 

Now to take this discussion from theoretical to real.

My real world experience when I shot film with manual flashes, for many years, was:

• Indoors, in an average size room in a house (say 15x10ft with 8ft white ceiling), the GN on the flashes that I used, was close enough for a good exposure.
  
• Outdoors or in a large banquet hall, the GN was 1 stop low, and I needed another stop more exposure.
   
  
• This was consistent for ALL my manual flashes.
   
  
• This was based on film exposure, not a flash meter test.
  

When I switched to digital, I used first an Automatic flash, then a TTL flash. So, with digital, I do not use the GN calculator.

So, for today's flashes, I have no idea how close or far the mfg GN is from reality.

[q.g._de_bakker]

I think both Joe and I do not complain about the usefulness of the GN. We said the GN are always inflated and was done intentionally. A way to make a product seems better than what it is. If we during testing the GN and found they are greater than the manufacturers claim they are still not useful but we wouldn't complain about that. The fact that none of the flash I tested so far and I think Joe too would come up with a GN greater than claimed by the manufacturer.

You feel cheated by a number known to be meaningless other than as a thing to use to compare different flash units.

That (provide a comparison) they do well. Where's the deception? What wrong was done to you?

[BeBu Lamar]

You feel cheated by a number known to be meaningless other than as a thing to use to compare different flash units.

That (provide a comparison) they do well. Where's the deception? What wrong was done to you?

The cheating is obvious and intentional and the number is in fact not meaningless.

[q.g._de_bakker]

The cheating is obvious and intentional and the number is in fact not meaningless.

You take it for more than it is.

And then feel cheated because it isn't.

[rodeo_joe1]

So what is the reference "non-reflective room?"

It's obviously meant to be literally totally non-reflective, and as close to free-space as possible. Such that only the direct light from the flash is measured. Otherwise it wouldn't be much of a standard - and it obviously isn't!

 

However, weasels will seek out weasel-wording and use it to their own advantage.

 

In any case: The difference between a direct-flash exposure and a fully-bounced exposure is about 2 stops in a room with an 8' 6" high and matt white-painted ceiling at a distance of 2 to 3 metres from the subject. (see examples below) Therefore, even in those fairly optimum conditions, the reflected light only contributes at maximum about 25% to the directly-lit version. Making a difference of +1/3 stop compared to a free-space exposure. This is a long way short of the 1 stop exposure difference from the maker's Guide Number when measured, or found empirically.

 

 

Guide Numbers are 'only' a guide, agreed, but there's being in the right ball park and then there's not even being in the same city! That's the difference.

[BeBu Lamar]

[quote="rodeo_joe|1, post: 5929083,

Guide Numbers are 'only' a guide, agreed, but there's being in the right ball park and then there's not even being in the same city! That's the difference.

 

They said it's only a guide and not accurate OK but if something is not accurate it can err on either side but as you found out it only err on the low side so that I say the error is intentional.

[Bill C]

It's obviously meant to be literally totally non-reflective, and as close to free-space as possible. Such that only the direct light from the flash is measured. Otherwise it wouldn't be much of a standard - and it obviously isn't!

 

Fwiw I doubt that the room layout has much effect on those little hot-shoe flashes. They get good power efficiency by putting most of their light into a narrow zone that the lens is looking at. So what I'm suggesting is that there is not much extra light to be spilled onto the walls of the room, reflective or not. (No, I haven't tried this to see, but I have, in the past, had a look at the flash illumination patterns at various zoom settings; the more recent "dedicated" hot-shoe flashes set their zoom settings to match the camera lens.)

 

A note in defense of the ISO standards... in the past I've used a number of ANSI standards (the ISO standards seem to be essentially the same, or at least very similar). And I've found them to be pretty good, without loopholes for the most part. I suspect what is going on here is not an ISO issue, but rather people presuming that their flash unit guide numbers conform to ISO standards.

 

So here's a question for the users of overrated flash units... does the manual for your flash say it uses ISO-based guide numbers, or in any way conform to ISO?

[q.g._de_bakker]

They said it's only a guide and not accurate OK but if something is not accurate it can err on either side but as you found out it only err on the low side so that I say the error is intentional.

It could be that you consistently have too optimistic expectations of something, and like to blame that on someone else.

[BeBu Lamar]

It could be that you consistently have too optimistic expectations of something, and like to blame that on someone else.

I am the most pesmimistic person around. I know when they cheat and when they don't know.

[q.g._de_bakker]

I am the most pesmimistic person around. I know when they cheat and when they don't know.

So your pessimistic nature will be why you see something to complain about where there isn't anything to complain about.

[rodeo_joe1]

So here's a question for the users of overrated flash units... does the manual for your flash say it uses ISO-based guide numbers, or in any way conform to ISO?

A very good question!

After searching through my extensive collection of flash instruction manuals - from Nikon, Metz, Sunpak, Nissin and the like - I can find no claim of adherence to ISO or other recognised standard apart from use of ISO in reference to film/sensor speed.

 

With one exception; an old Braun manual quotes this: "Specification of the

Braun F 900 Professional

(ln accordance with DIN 19011)"

 

Which is printed next to a table of Guide Numbers.

 

DIN 19011 was a superceded German standard for the determination of flash output, and nothing to do with the current DIN/EN/ISO 19011 standard that waffles on about auditing management methods.

 

Nothing more modern seems to even hint at adherence to a standard, outdated or otherwise. So I guess, as suspected, that makers' Guide Numbers are worth less than the virtual paper they're printed on.

Except to be divided by 1.5 as a realistic starting point.

Edited November 23, 2021 by rodeo_joe|1

[q.g._de_bakker]

No! Do not use Guide Numbers as a starting point for whatever.

[rodeo_joe1]

So? What? In the absence of a flashmeter we stick a wet finger in the air and guess at a flash exposure?

 

Empirical experience shows us that nearly all published Guide Numbers are exactly one stop short of a picnic. So why not use a figure that's proven itself in practise to be a good starting point?

 

I.e. Divide the maker's lying and connived figure by 1.4 or 1.5, and you're pretty much good to go.

[BeBu Lamar]

So? What? In the absence of a flashmeter we stick a wet finger in the air and guess at a flash exposure?

 

Empirical experience shows us that nearly all published Guide Numbers are exactly one stop short of a picnic. So why not use a figure that's proven itself in practise to be a good starting point?

 

I.e. Divide the maker's lying and connived figure by 1.4 or 1.5, and you're pretty much good to go.

Joe I am sure they conform to a standard which we don't know about.

[rodeo_joe1]

Joe I am sure they conform to a standard which we don't know about.

And by their ridiculous pricing and policing of the Internet, those Swiss ISO gnomes are determined that all of their standards remain 'secret'.

 

Naively, I used to think that national standards were there for the public good, like checks on weights and measures. The ISO have proven that to be a totally misguided view. It's not like they even bother to create the 'standards' themselves these days; they just leave it up to a committee of bean-counters experts employed by large corporations.

[BeBu Lamar]

And by their ridiculous pricing and policing of the Internet, those Swiss ISO gnomes are determined that all of their standards remain 'secret'.

 

Naively, I used to think that national standards were there for the public good, like checks on weights and measures. The ISO have proven that to be a totally misguided view. It's not like they even bother to create the 'standards' themselves these days; they just leave it up to a committee of bean-counters experts employed by large corporations.

I just go by deduction. As you find out you can pretty much tell the real GN of a flash by its published GN so they must be following a standard somewhere. Now for the ISO I found it's a very silly things. It seems to exist only to allow manufacturers the ability to claim that they follow the standard.

[q.g._de_bakker]

ISO, as far as quality standards are concerned, allowed or still allows companies to set their own standards. A certificate was/is no more than a promise that the company receiving the certificate would aim for that standard. Not that the standard was high.

 

Anyway, this entire thread is one complaint about a certain number that represents something so well that it is deemed rather usefull.

I would complain about such a thing too, if i had nothing else to do. Maybe.