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10-16-2019, 05:44 PM   #256
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Thanks for the clarifications, I think that I see now more clear what is happening, but let me answer point by point, and try to clarify how this thing works (or how I think it works)

QuoteOriginally posted by Hattifnatt Quote
I will test more tomorrow, maybe the exposure actually changes but the flash and trigger LCD's are not in sync
Ok, I think you have no problem here. Regarding the EV compensation for the flash, you will notice that you can set a compensation on the Flash itself, and also on the trigger. Well, the key here is to understand that both settings are local and independent, they will never sync up. When you set EV on the AD400's LCD, this is a local compensation that the flash knows, but it's not related with the EV compensation you set on the trigger, that is, both compensations will sum up.


In fact, you have four ways to change a flash exposure compensation:


1. On the flash itself, you press the SET button, dial the wheel, done
2. On the trigger, so you select the group, dial and set the compensation
3. With camera on M mode, you can use the +/- EV compensation camera setting
4. On camera, flash function, you can configure a compensation for the flash too

This is a super-flexible way to change compensation. My preferred and most used method is 3.

All above ways are independent, and will sum up to the final compensation you set for the flash. As an example, If I set -1EV on flash, -1EV on the trigger, and -1EV on camera (in M mode), I'll have a total compensation of -1 + -1 + -1 = -3. Believe me, I made the test a minute ago (to be 100% sure), changing every compensation one at a time.

So, I think you have nothing wrong related to what you see on the display or on the trigger. This setting will not sync, doesn't work this way.


QuoteOriginally posted by Hattifnatt Quote
I didn't try to see if it works if I only set it on the trigger. I set it active on both flash and trigger. Then I noticed when I disable it from trigger, the icon still stays active on flash.
Ok, second mistery. I think again you have nothing wrong here. But let me explain how I think it works. When you change the HSS status on the trigger, you'll see nothing on the flash, this is correct behaviour. But you'll notice that, when HSS is OFF on the trigger, you can't go above 1/180 speed on your camera, this is the only apparent effect. If you set HSS to ON, then yes, you can go beyond this speed.
When you fire it's when you'll notice that the HSS status on flash is set, and the flash will fire in the correct HSS mode. You don't need to change anything on the flash, just in the trigger, but remember that nothing changes on the flash LCD before you shoot, just when you shoot.

So again, I think regarding the HSS mode, your flash and trigger are OK.

QuoteOriginally posted by Hattifnatt Quote
I was using Av mode. Did some tests and I thought the exposure was not affected... maybe -1 was not enough to see a change and I should have tested with -3
Please repeat your tests with more compensation and be sure you put enough distance from your flash to your subject; your flash is really powerfull, maybe it can't go so low to compensate for -1 or so.
There is another point about the pre-flash. I noticed, when I put the flash too near a subject, that the exposure is not correct, but the problem is not that the flash can't set a low enough output power, I think the problem is with the pre-flash. I measured that the preflash is 1/8 of the total power, so if you are really too near to your subjetc, I think the pre-flash is so powerful, that the camera doesn't know what to do, and calculates a wrong exposure. Just put a little more distance, and the problem dissapears.

BTW, do you see a pre-flash, don't you ?


Last edited by morenjavi; 10-16-2019 at 06:05 PM.
10-17-2019, 03:43 AM   #257
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QuoteOriginally posted by morenjavi Quote
Thanks for the clarifications, I think that I see now more clear what is happening, but let me answer point by point, and try to clarify how this thing works (or how I think it works)
Thanks a lot for taking the time to help me and write all this detailed answer! Much appreciated.

QuoteOriginally posted by morenjavi Quote
Please repeat your tests with more compensation and be sure you put enough distance from your flash to your subject; your flash is really powerfull, maybe it can't go so low to compensate for -1 or so.There is another point about the pre-flash. I noticed, when I put the flash too near a subject, that the exposure is not correct, but the problem is not that the flash can't set a low enough output power, I think the problem is with the pre-flash. I measured that the preflash is 1/8 of the total power, so if you are really too near to your subjetc, I think the pre-flash is so powerful, that the camera doesn't know what to do, and calculates a wrong exposure. Just put a little more distance, and the problem dissapears.BTW, do you see a pre-flash, don't you ?

I don't know if I see a pre-flash. I should have asked the model. I think the flash was just too close to the subject. Now I'm thinking that I should have realized this is what happening and maybe test it in two ways:

- put the flash in manual mode, set it to minimum power and see what happens with the exposure;
- after a TTL shot, press that button that converts TTL to manual settings and it should been 1/256, if the flash realized it needs to lower the power as much as possible, right?

Anyway, I will play more as soon as I have the time.
10-17-2019, 03:58 AM   #258
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QuoteOriginally posted by morenjavi Quote
I measured that the preflash is 1/8 of the total power, ...
How did you measure it in isolation?

Is there still a pre-flash when the flash power is set to zero?

I don't use TTL, just curious how you measured the pre-flash intensity.

I guess if a lightmeter measured both the pre-flash and flash, one could do two measurements with different (known) flash powers and then factor out the pre-flash contribution.
10-17-2019, 04:17 AM - 1 Like   #259
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QuoteOriginally posted by Hattifnatt Quote
- after a TTL shot, press that button that converts TTL to manual settings and it should been 1/256, if the flash realized it needs to lower the power as much as possible, right?
It's a very good idea; yes it should indicate 1/256. A great use of the TCM function is to know if you are near the limits of your flash. My AD200 has half the power of yours but the minimum power is just 1/128, so I think I have exactly the same minimum power than AD400. When I use a softbox, I can put everything really close my subject without problems. If I use another accesory like the standard bowl then I have to take care with the distance, I think it's because the pre-flash but who knows.

Good look, I hope you don't find any problem with your flash.

---------- Post added 17-10-19 at 01:31 PM ----------

QuoteOriginally posted by Class A Quote
How did you measure it in isolation?

Is there still a pre-flash when the flash power is set to zero?

I don't use TTL, just curious how you measured the pre-flash intensity.

I guess if a lightmeter measured both the pre-flash and flash, one could do two measurements with different (known) flash powers and then factor out the pre-flash contribution.
It's a very good question. I measured the pre-flash with my photometer time ago. I don't remember exactly why I did it, but I think I was doing some measurements with the AD200 in TTL mode and I noticed that I was not measuring the real burst but the pre-flash. So, as I know the total power of my flash and the value of (what I thouhgt were the) pre-flash, I reached the conclusion that the pre-flash was 1/8 of the total power, so I 'stored' this value on my memory as a good one .

Anyway, I'm going to take these measures as you suggested, min, max and 'pre-flash' to see if it's exactly 1/8. Maybe the tests I did in the past were not 100% precise.

---------- Post added 17-10-19 at 01:36 PM ----------

To clarity, I'm quite sure that my photometer was measuring the first pre-flash and not doing some kind of average with the real burst. I think I was forcing the flash to go max power ... but I don't remember exactly. I'm going to repeat the test, and I'll tell you more details.

10-17-2019, 05:36 AM - 1 Like   #260
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Hello again. I made the tests.

I mounted the bare-bulb on my AD200.
I put my photometer (lovely Sekonic L-358) at a distance so I measure exactly f2.8 0 at minimum power. Then I took three measures in manual mode:

flash power ----------------- photometer measure

1/128 ------------------------- f2.8 0
1/8 ---------------------------- f11 0
1/1----------------------------- f32 1

Then I changed the flash mode to TTL and took several measures again, pointing the camera just to a ramdom place

pre-flash -------------------- f8.0 6

I have repeated the TTL measure forcing -5EV and +5EV compensation for the flash. The value remains the same.

f8.0 6 is more or less the value I get when the flash is set at 1/8 and dial down -0.3EV.

So, I think we can conclude that the pre-flash is aprox. 1/8 of the total power for the flash .
10-17-2019, 06:01 AM   #261
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QuoteOriginally posted by morenjavi Quote
Hello again. I made the tests.
Great stuff, thanks!
10-29-2019, 09:21 PM - 1 Like   #262
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Flashpoint R2 Pro Mark II Available

Good news!

The Flashpoint R2 Pro Mark II is no long on backorder but now in stock.
I should receive my unit in a couple of days.

For those who are not aware of this trigger, it is an improved version of the Godox XPro-P (aka Flashpoint R2 Pro).

In comparison to the XPro-P, it adds Bluetooth connectivity (analogue to the X2T-P (aka Flashpoint R2 Mark II) but more importantly improves usability quite a bit.

The group buttons are arranged around the wheel for quicker access and directly support turning the groups on and off (without involving the "MODE" button as is the case on the both Godox triggers or the Flashpoint R2 Pro).

There are also a lot more dedicated direct access buttons for various functions, obviating the need to perform multiple button presses (or long presses) and remembering when and where the respective function becomes available through the soft keys.

It comes with all extra features that have appeared on recent triggers such as TCM or channel scanning and adds extra ones like back-lit buttons.
If I'm not mistaken, no other trigger supports remote control of the modelling light power.

I'm excited that Adorama went ahead and finally made a Pentax-dedicated version of this trigger (it has been available for other brands since October 2018), and that it is shipping now at last.
Can't wait to give it try.
10-29-2019, 10:11 PM   #263
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QuoteOriginally posted by Class A Quote
I'm excited that Adorama went ahead and finally made a Pentax-dedicated version of this trigger (it has been available for other brands since October 2018), and that it is shipping now at last.
Can't wait to give it try.
My needs are easily met with regular speedlights and simply TX, but I can definitely appreciate what these recent Godox/Flashpoint products bring to the table. This is very good news.


Steve

10-30-2019, 01:46 AM - 1 Like   #264
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QuoteOriginally posted by Class A Quote
Good news!

The Flashpoint R2 Pro Mark II is no long on backorder but now in stock.
I should receive my unit in a couple of days.
Congrats! I have a healthy envy.
Anyway I cound't afford more triggers, seriously, I have too many.
11-10-2019, 09:21 AM   #265
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My Flashpoint R2 Pro Mark II has arrived. Haven't had time yet to put it through its paces.

Let me know if I should check something.
12-04-2019, 04:34 PM   #266
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QuoteOriginally posted by Class A Quote
Let me know if I should check something.

Can you set 2nd curtain sync with this trigger??

davek
12-05-2019, 07:55 AM   #267
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QuoteOriginally posted by dave kitson Quote
Can you set 2nd curtain sync with this trigger??
Unfortunately, you cannot (with this "for Pentax" version).

The "for Nikon" version supports second-curtain sync.
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