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07-28-2018, 06:36 PM   #16
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QuoteOriginally posted by mcgregni Quote
Sorry for the delay, I missed this for a while. I believe that with an "A type" lens, even though the aperture is coupled and controlled by the camera, multi-pattern does not work (despite appearing to be active), and it defaults to centre-weighted. This is because the focus points can't provide their input .... This is also the reason that P-TTL flash metering is not "officially" supported with A type lenses, and as has been mentioned before in relation to your Samyamg 85mm, you should not expect very accurate and consistent P-TTL flash exposures.

Your nice new DA35 should be fine thought!
So even though my Samyang 85/1.4 is showing Matrix/Multi-pattern as being allowed (ie it can be used and chosen/selected), when it comes to taking the actual shot itself I am not to trust it, it's prolly using centre weighted instead?
I find this curious because I have a bunch of A lens that won't even allow Matrix/Multi-patterned to be selected or used, the option is just not there...
You don't think the Samyang has some kind of other tech involved that somehow gets around the issue to providing the user with a functional Matrix option?

07-29-2018, 01:45 AM   #17
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It's a good question, and like most good questions we usually only learn from it by testing our assumptions. I've got a couple of SMC A lenses, plus a Samyang 14mm (which I assume has the same lens to camera contacts as your 85mm ....), so I'll try them out and see if I get the same results as you. Also I'll see if I can demonstrate that the metering is the same when set to centre-weighted and multi-pattern.
07-29-2018, 07:11 PM   #18
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QuoteOriginally posted by mcgregni Quote
It's a good question, and like most good questions we usually only learn from it by testing our assumptions. I've got a couple of SMC A lenses, plus a Samyang 14mm (which I assume has the same lens to camera contacts as your 85mm ....), so I'll try them out and see if I get the same results as you. Also I'll see if I can demonstrate that the metering is the same when set to centre-weighted and multi-pattern.
Appreciate the feedback, although the difference between spot and matrix is night and day I am concerned that I am not adept enough to succeed in doing a good test between matrix and centre weighted
07-30-2018, 03:05 AM - 1 Like   #19
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Hello,

I have the Samyang 85mm too. In my case I get same results for metering regardless if I choose Matrix or Center weighted.
A good test for testing differences between Matrix/Center is to put a bright light outside the center zone, in center weighted, this light is ignored, but not in Matrix. Also if you check 'Link AE and AF point', and focus to that light, you will see more a noticeable difference. This test can't be done with the Samyang, as you can only use the center point.

No difference then, Matrix or Center the measuring is the same, in my tests.

Regards.

07-30-2018, 05:05 AM   #20
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QuoteOriginally posted by BruceBanner Quote
I am concerned that I am not adept enough to succeed in doing a good test between matrix and centre weighted
It should be recorded in the exif data
07-30-2018, 05:17 AM - 1 Like   #21
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I can confirm that, for the Samyang, this info is recorded.

---------- Post added 30-07-18 at 02:44 PM ----------

About using the camera in manual mode with a flash, I have my camera in M mode most of the time, so I can comment on how I solve some situations, but there are so many possible situations and combinations...
My setup is different if I work inside (low or no ambien light) or outside (lot of ambient light).
When I'm inside: I work year from year on the same church so I know every wall, room or tile. I have a couple of external lights that give me my 'ambient light', as the real ambient light in my case is low and also no good quality (mix of light form windows and incandescent bulbs). So first I set the 'ambien light' for the most important area, with the help of my photometer. f4.5, 1/160 and ISO 320 are my usual settings inside, for the kids seated during the ceremony.
Also I have a PTTL flash mounted on camera with a small bouncer, if I need some fill light because a kid is in shadow or doesn't receive good light from my 'ambient flashes', then I set my flash on camera to ON, and control the flash compensation with the camera's EV dial. EV -0.7 is a common setting for me. In M mode, EV dial controls the TTL flash compensation, better and faster than changing FEC from the flash itself. Ambient light will not change by dialing the EV compensation, only main flash.
If I have just my flash on camera, inside, I make the usual bouncing to a white wall, and it's done.
But I'm afraid the above is not similar to your case, usually you have no choice to put so many lights inside a churh.
When I'm outside, I get my camera, a foldable lightstand with my AD200 and a small umbrella. Outside I usualy make posed portraits for kids and families, so I have a little time to make a setup, but I have to work fast, because there are more families waiting. I avoid harsh sun and look for a site with shadow and not too ugly background. I don't use HSS (maybe next year). I get my photometer and my remote flash control, set lowest ISO and take a metering, this is my base metering for ambient. Then I take a second measure adding the flash, correct flash power until the flash contribution is in the range 30%-50%, set my camera and then I take the shots. Usually my flash is set previously with a reasonable power setting so I need to make few corrections to get the setup done. I can make this setup really fast, but need a bit of time.
If I have only my camera and a PTTL flash mounted on top, outside, and no time to posing, then I put lowest ISO, and change speed/aperture to get a correct exposure with reasonable amount of ambien light, then I underexpose a bit and, for the flash I dial EV -0,7 or so. My idea is to get good mix of ambient light and flash light, I keep shooting on the same area so the settings are valid. If light changes you will need to make corrections. When you are in M mode, the EV compensation changes the compensation for the flash (becomes FEC dial), this is for me a great trick that allows to change the flash power setting really fast. So, in short: I first set the camera for ambient and then dial EV for the flash until I see a 'reasonable' amount of flash light. Tv/Av for ambient corrections, PTTL flash will not change.
In a situation outside with only a manual flash mounted on camera, I'm afraid I must memorize a flash power for a fixed ISO-distance-Av. For example, 1/8 power setting could be good for 1.5 metters, ISO 100 and f5.6, and this can be my starting point. You could play with the speed dial to control ambient, if needed. I never used the above in 'real' situations, only experimented at home, but for me it's not a bad idea, just keep the distance to your subject and you will have a more or less correct exposure.

Regards.

Last edited by morenjavi; 07-30-2018 at 11:53 AM.
07-30-2018, 08:59 AM - 1 Like   #22
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You've covered some very interesting points there, thanks! The one about the compensation setting being applied to "Flash Compensation" when in M mode is interesting, as I thought it had been said here earlier that setting a compensation amount in M mode has some other effect ..... ? I can see though that if it applies to Flash Compensation then it is a useful feature, easier than operating the setting on the flash itself, and indeed the actual Flash Compensation setting on the camera ....(although perhaps the K1 has a position for this on the multi-function dial?)

BTW, I have to look away every time you write "FEC" .... ahhhh!!! that reeks of Canon, and I have banned the term here


I have also now completed some tests with the Samyang 14mm and SMC A 28 F2.8 .... My findings were the same as yours Morenjavi. The behaviours of both lenses were exactly the same in terms of metering modes. Both had no difference in EV obtained in either Centre-weighted and multi patterned modes (I had half the frame a bright window, half the darker wall below .... in multi-patterned with an AF lens the exposure is darkened a little to account for the extra amount of brightness outside the window being measured.


Both lenses worked in spot mode, and this appeared to function as expected.


Regarding the metering mode indications .... I noticed that the LCD Status Screen indication DID change to multi-pattern, even though that mode clearly was not working ...... however, the viewfinder indication did not show multi-pattern with these lenses ; when selected, the indication in the viewfinder disappeared. It returned when Centre or Spot were set.
07-30-2018, 10:53 AM   #23
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I don't remember where and when read about using the EV in manual mode to compensate for the flash, but I've been using it since then, during several years. Never seen any (negative) effect or disadvantage.

For me, the main advantages are:
1. faster compared to set compensation on flash
2. (theoretical) range of compensation from -5EV to +5EV (a typical flash have only -3EV to +1EV)
3. EV compensation is registered on EXIF data, so you know how much flash compensation was used on a pic, when you review it months or years later. As far as I know, the 'real' Flash compensation is not registered on EXIF data.

If I have a flash/camera combination that needs a fixed compensation (for example my K5 and metz 48 AF-1 needs a fixed -0,7EV compensation, always, to avoid overexposure) I put such compensation on the flash, but then I use the EV compensation on camera as needed, when in M mode.


Regards,
Javier.


Last edited by morenjavi; 07-30-2018 at 10:59 AM.
07-30-2018, 11:34 AM   #24
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Thats a good approach, yes ,as the settings accumulate. I'll give it a go, thanks! I wonder if the Flash Compensation setting, as controlled from the camera main compensation control in M mode, is indicated on the flash mode screen. Again, more things to test and add to our collective knowledge base!
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