All you know is that it will deliver you .4 seconds faster recycleing
and that is only when the unit has fully discharged. There is no
difference at all if the capacitor has not fully discharged and has
enoug residual charge that it can still fire which i s more than 90%
of the time. I suspect that the SB800 it will deliver significantly
more consistent results, flash after flash, if it is used within the
original design parameters of the unit which is with 4 battereis
rather than 5.
If you can show me these original design parameters, I'd consider this view. But without these, all I can think of that you are trying to say (and its a little unclear to get to the bottom of exactly what you're getting at) is that the SB800 might deliver more consistent results because of ..... well ... what? the fact that four batteries is limiting the recharge time, therefore limiting the heating of the flash circuitry perhaps ??
In this case, you need to be a bit more specific, because you can use four low internal resistance batteries and get near enough the same recharge time as using five NiMH ones, so using the wrong FOUR batteries will by this logic cause the same inconsistent results.
And as for the partially discharged capacitor comment. Yes, this could be the case, but so could shooting in FP mode outside, or doing bounce flash indoors, in which case (especially the latter) its highly possible you are pretty much flat out and hitting full power all the time, so I still maintain that having the fifth battery is a significant advantage in real use for a lot of people. It certainly is for my partner and I. That 90% figure certainly doesn't apply to us.
And since I've noticed that the Nikon flash system will allow you to take a shot when the flash has not completely recharged (hence a second instantaneous flashed image will be darker then the first, or a second one that's had enough time to fully recharge) I would argue that you stand a better chance of getting shot to shot consistencies in fast paced real life scenarios if you DO use the fifth battery pack and you DO use low resistance cells.
I still have 5 batteries hooked up but I am considering taking the
fifth one off.
Like I said. I think this is the cart leading the horse. If you believe you are having consistency problems, a far more logical alternative is to alter your shooting style rather than take the fifth battery off. The only argument against this is if you are aware that you or another shooter that uses the equipment is either incapable or unwilling to adhere to the new regimen, in which case, yea ... artificially force them to have lower recharge capabilities, but if you're doing this, then why stop at the quantity of batteries? shouldn't you be also using ones with a higher internal resistance?
Personally, in a professional environment, I'd rather know that I can get that shot that needs as fast a recharge time as possible. I can choose to limit my firing speed most of the time (and I do) I can't choose to miraculously speed up a slowly charging flash if I happen to occasionally need it.
I do not agree. We do not know if it has anything to do with the life
of the xenon flash tube at all. It is much more likely that it is
related to the electronics. Flash tubes either work or they dont and
when they quit they dont just start working again.
Hmmm.... are you sure about this categoric statement. I mean ... REALLY sure ??
because I'm not.
Yea, if a flash tube has exploded or cracked in half, then I agree its not going to miraculously start working again. However the reason I asked about whether the flash works in manual but plays up in TTL mode is that there seems to be a common failure mode whereby the flash LOOKS as if its fired, but all you are actually seeing is the measuring preflash. The main illuminating burst will often fail to trigger. Its almost as if some molecular properties of the gases within the flash tube need a finite time to reform after the last burst of ionization, but as the tube ages, this time period lengthens to the point where the TTL preflash v main flash is too short and you don't get adequate time for this to happen.
Now of course, I can hear you already start to argue that it could be the triggering electronics that's the cause and not the tube. However I have had such a faulty flash unit myself where I personally replaced the tube (and boy, visually was it obviously 'well used' with what looked like a myriad of fine hairline fractures in the glass - even though it had NEVER been abused), and voila! a fully working flash again (and to reiterate - this flash was doing the strange intermittent behavior that you were originally describing). Its possible that I disturbed something else doing the swap, but now its getting statistically very unlikely and its far more plausible to consider that as tubes age, they do exhibit some strange characteristics. I know that their light output varies with age, so it could be something linked in with that and the power delivery measurement algorithm of the TTL part of the whole flash unit itself not letting it fire. I don't know, but that's immaterial. All the evidence points to the fact that tubes aging cause the flash unit to play up so you have to accept that you're either going to have to get the tubes replaced at some point, or you need to treat the flash unit as a consumable product with a finite life.
pto
