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12-22-2012, 02:31 PM   #31
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QuoteOriginally posted by Ben_Edict Quote
IDM works off the film surface. That is not possible with the sensor surface of a DSLR - otherwise the old players with these film-based measurement systems would also have stuck to it, like Sony (Minolta held the original patent for this technology), Olympus (the first on the market) or even Nikon (F3 and later).

Sensors have completely different reflective properties, which are obviously not so easy to manage and create a whole set of problems, which did not exist in film days. The istD was the last Pentax DSLR, which sported flash-TTL metering and it was of not really much use - at least I did not find it any more realiable than P-TTL. Simple A flashes work best anyway...

Ben
The difference in reflection is a calibration issue only, the *istD was just as good in TTL and P-TTL. I have shot both with no issue.

12-22-2012, 03:21 PM   #32
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With the *ist cameras, TTL works only with an M lens ( or A lens off A position) and in M Mode. Also I think it has to be in iso 200.
The flash is controlled by quench circuitry in the camera.
The AF360 flash shifts into TTL mode when activated with a half press of the *ist's shutter button
With speeds in range 1/45 to 1/125 or so, the TTL mode considers the ambient light, so the *ist s will chop the flash right down to be fill flash for the correct exposure.
12-22-2012, 03:45 PM   #33
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QuoteOriginally posted by wombat2go Quote
With the *ist cameras, TTL works only with an M lens ( or A lens off A position) and in M Mode. Also I think it has to be in iso 200.
The flash is controlled by quench circuitry in the camera.
The AF360 flash shifts into TTL mode when activated with a half press of the *ist's shutter button
With speeds in range 1/45 to 1/125 or so, the TTL mode considers the ambient light, so the *ist s will chop the flash right down to be fill flash for the correct exposure.
Not so, it can work on an A lens with a TTL flash like the AF500FTZ.

It can be in any ISO, I often worked at ISO400 because there was no noticeable noise increase and I got further flash range

I always shot in M and set exposure to what I wanted with natural light so I never had exposure issues, it was always spot on
12-22-2012, 04:15 PM   #34
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IMO there are no excuse for Pentax. This is a plain removal of a useful feature just to cut industrial costs (of just a few dollars) per camera.

Admitted that Pentax/Ricoh wants loyal customer I think should fill these gaps.

12-22-2012, 06:34 PM   #35
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QuoteOriginally posted by seppstefano Quote
IMO there are no excuse for Pentax. This is a plain removal of a useful feature just to cut industrial costs (of just a few dollars) per camera.

Admitted that Pentax/Ricoh wants loyal customer I think should fill these gaps.
No disagreement. The top of the line camera at least should support both, like the *istD does
12-25-2012, 06:42 AM   #36
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QuoteOriginally posted by Lowell Goudge Quote
Not so, it can work on an A lens with a TTL flash like the AF500FTZ.

It can be in any ISO, I often worked at ISO400 because there was no noticeable noise increase and I got further flash range

I always shot in M and set exposure to what I wanted with natural light so I never had exposure issues, it was always spot on
Lowell,

TTL in the older Pentax bodies had a couple of limitations, one of which was a limited ISO range of 200-400 for the istDS, 200-800 for the istD

The other was underexposure near minimum aperture and overexposure near maximum aperture when using fast lenses for the istDS. This issue is not noted for the istD.

I never found an official explanation of the problem with TTL and digital, but it's certainly gone from all of the DSLR brands as far as I know.

Ray
11-13-2017, 09:54 PM   #37
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QuoteOriginally posted by A Quote
there are two parts to this.

I think the issue is that in certain exposure conditions TTL is not as accurate because after the flash there is still ambient light which can lead do over exposure in some cases. Also TTL requires a separate flash sensor, and inout channel. P-TTL uses the main metering system and is therefore cheaper.
.
Not correct with TTl and ambient light when you set up to shoot a photo the ambient its taken into consideration by the camera and a lesser amount of flash is provided by the flash this usually is done in aperture or manual modes with the digital cameras they no longer provide this ability unless in full manual mode the result is for example at a wedding you want to capture a room full of people with the bride and groom you would set your camera to 30-125 shutter speed and a F3.5 this will capture the main subject with the flash at a lower intensity and the ambient light will allow the rest of the people to be exposed and because a low shutter speed is used the amount of over exposure would not occur why? because its practicly impossible to over expose film at night unless the interor lighting is too bright. I also do long exposures at night with digital without overexposure. TTL actually measures the ambient light then caculates the amount of additional light required by the flash. This is why TTL was so good.

The reason over exposure occurs with flash is because program mode is used which reduces the the ambient light as the aperture is heaps smaller and a full flash of light is displayed on the finish product this happens to beginners and and people that want to play the safe game. This P-ttl stuff it is all new to me I've only learn't it exist the last few days but TTL I won awards with it because I understand it and how it works. Now I have to learn P-ttl See my Pentax istd has ttl and last year I got a K-m and it doesn't have TTL so now I have to learn it.

The fact that digital sensors read extra light is mostly incorect as the new lens are coated with a metalic coating to reduce flare so sensors are also not an issue.

Years ago I had a flash that metered its own light and when taking a photo of the sunset with subjects in the fore ground I would have to put tape over the sensor that read the light because as soon as I took a photo the flash would switch off and leave me with an under exposed photo because the sunlight was switching my flash off hence the tape over the sensor took a few sessions to solve that issue. This was pre TTL. I think I might still have that flash could be handy.

Looks like P-ttl controls the F stop and the flash blast taking control away from the photographer even though the shutter speed is set by the flash. I think we need a camera where the photographer can set the F stop setting which controls the flash and measurers the ambient light because ambient light is currently ignored by P-TTL hence a exposed person and a black background. Mabye some clever dick used the ambient light factor in a misleading way when premoteing digital cameras hence eneryone thinks abbient light is being measured when in fact its only being dealt with by cutting it out by using smaller apertures. So looks like I am starting to get my head around this. We need better digital cameras these aren't good enough.

---------- Post added 11-13-17 at 10:01 PM ----------

Bring back TTL


Haven't tried this yet but I think the further away from you subject the better the lighting from your flash will appear. as this will open your aperture bigger which will let in more light and may also reduce the flash required however it may or may not wash out items closer than your subject but to be honest I have a feeling it won't because I think its still the same metering system but the control have been given to the camera and not the photographer hence the requirement for it to know / set the F stop. If we can make the camera change the f stop possibly by moving away we regain some control. But there is the full manual mode which will not let us down i hope. Well I better go test these new theories now.

I think also the 1.5 factor with DSLR's over 35mm helps with the reduced over exposure with flash as we are 50% further away when taking photo's now which should have opened the aperture a stop or 2 causing less flash on the subject as the subject is further away.

Most of above was based on 200 iso with 080c ring flash Just shot off some around the house with my in camera flash on the K-m and I found opening the ISO to 800 introduced extra ambient light and I figure it either opens the aperature or extends the shutter timing I went from 200 to 800 iso that is 2 stops now I have no idea where these two stops were gained but when I added 2 stops to the exposure before increasing the ISO next to no change was gained so I think somthing weird is going on here because all settings are a stop apart. any way a great improvement in light indoors when increasing iso. I am going to have to try that on the ringflash. Hope you guys don't mine me experinenting with my thoughts here. I guess the change in ISO makes the sensors more receptive to light as the shutter speed would remain the same in flash mode and the aperture should be two stops down.

Wish I had of kept my interest up in photography after going digital as back when film was around we didn't have the advantage of changing the ISO each shot as it would have meant changing the roll of film over. so this is definitely a plus over film. It was the flash problems that really discouraged me and the fact that I don't believe photo's should be edited beyond a touch up. They never look right there is always a flaw even if only the photographer know's it it's still there. Most mistakes are with lightening and colour and to me they look awful but to the public their beautiful.


Last edited by Kombivan; 11-13-2017 at 11:46 PM.
11-13-2017, 10:31 PM   #38
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QuoteOriginally posted by Kombivan Quote
Looks like P-ttl controls the F stop and the flash blast taking control away from the photographer even though the shutter speed is set by the flash. I think we need a camera where the photographer can set the F stop setting which controls the flash
Use manual exposure so you control the ambient light and let P-TTL provide the flash output to light the subject. Use the flash compensation on both flashgun and camera to fine-tune the flash exposure.
11-14-2017, 11:29 PM   #39
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In the old days I think if the hot shoe had 4 pins on it it would TTL If it had 1 pins it wouldn't somthing like that. The AF500ftz was the first flash that I had that was TTL compatable along with the AF400T these worked well with the MZ-5 and had only 3 pins. The earlier MG and ME had only 2 pins I would guess this was a basic TTL meteriing but I don't remember. The K series lenses had only one pin so these would have been manually set flashes or just a standard flash When I got my IstD yeah we know what that sounds like after I got it I was told by the Camera guy that it was the last model that did TTL metering and I could use my old TTL flashes and manual lenses with it without having to change my style but somthing did change it was the flash wasn't reading the aperature ring settings any more like the MZ-5 would in america the MZ-5 is the Zx-5 so I been using the IstD up untill last christmas and not using the flash but long exposures instead Now I am getting a handle on the P-TTL but I still havent worked how I am going to use it as I like aperature priorty and I am not sure if it will read the aperture priorty even if I set it in the camera. OH I just bought another lens and your all going to say I got the wrong one I got a 185D 1999. its in really good nick I don't think its plastic and can you suggest a really light shade filter that will filter the flare and still allow the auto focus to work I am thinking possibly a skylight type of filter or one with a metalic coating like the newer lenses have any suggestions would be appreciated a polarizer would be too dark i think as would a ND filter.

---------- Post added 11-14-17 at 11:41 PM ----------

QuoteOriginally posted by pschlute Quote
Use manual exposure so you control the ambient light and let P-TTL provide the flash output to light the subject. Use the flash compensation on both flashgun and camera to fine-tune the flash exposure.
is there any way I can use the aperture priorty as this is what I like doing with night pothography. I can do it without the flash but can with the flash if I set it to flash I imagine I would have a setting of 125 I am not sure about shutter speed with flash as I haven't used it for 15 years. so I guess I set it to 125 and F3.5 with flash and see what I get eh but would i need a 200 iso or a 400 iso do you think just for a starting point I had a stroke 18 years ago so I want to get the info in my head before I start so I'm not fumbling around going down the wrong path.

What is Flash compensation? I haven't heard that term? is that 1/8 1/4 1/2 etc

---------- Post added 11-14-17 at 11:44 PM ----------

Will My AF500FTZ work with a DSLR K-m Pentax I beleive its TTL with 4 pin connector to the hot shoe?

---------- Post added 11-14-17 at 11:47 PM ----------

I also have the AF400T the 080cring flash will be on the Istd however now I have a chart I could use it with the K-m

Last edited by Kombivan; 11-15-2017 at 01:03 AM.
11-15-2017, 12:59 AM   #40
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My istd iso is 200-400-800 &1600 have I got a special one?
11-15-2017, 04:56 AM   #41
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Thank you Pschlute I was also told once the southern hemisphere was +0.5 comparred to 0.0 Northern Hemisphere must have somthing to do the the large body of water down here.

---------- Post added 11-15-17 at 05:00 AM ----------

QuoteOriginally posted by pschlute Quote
Use manual exposure so you control the ambient light and let P-TTL provide the flash output to light the subject.
Does the TTL flash still work properly on a p-ttl camers body (forget the lens with this question)
11-15-2017, 05:47 AM   #42
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QuoteOriginally posted by Kombivan Quote
s there any way I can use the aperture priorty as this is what I like doing with night pothography.
You can use Av mode yes. But why would you want to for night shots?

QuoteOriginally posted by Kombivan Quote
What is Flash compensation? I haven't heard that term? is that 1/8 1/4 1/2 etc
No. Flash compensation is in stops and ranges from -4 to +2 with the AF540 FGZII. You tell the flash to over or underexpose by an amount in stops from the P-TTL baseline reading.

QuoteOriginally posted by Kombivan Quote
Will My AF500FTZ work with a DSLR K-m
In manual flash output only I believe. This is because the flash is not P-TTL compatible, and the K-M is not TTL compatible.

QuoteOriginally posted by Kombivan Quote
Does the TTL flash still work properly on a p-ttl camers body (forget the lens with this question)
Only in Manual mode. A TTL flash cannot work as a P-TTL flash on a modern body.
11-15-2017, 06:18 AM   #43
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Thank You thats very helpful

---------- Post added 11-15-17 at 06:21 AM ----------

AH but it will still work as a slave flash won't it

---------- Post added 11-15-17 at 06:27 AM ----------

It will also still post flash but in manual settings.

---------- Post added 11-15-17 at 06:31 AM ----------

I must admit I have been envious of the crystal clear surf shots the nikon and canon guys get and I wonder why can't I get those shots? possibly because I'm not swiming around in the ocean with a camera but their shore shots are still sharper than mine.
11-15-2017, 09:23 AM   #44
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QuoteOriginally posted by Kombivan Quote
AH but it will still work as a slave flash won't it
It may work as a slave if you set the flash to "dumb" slave mode, so it simply flashes at the power you have set when the main flash is triggered. You will have to use manual flash on the main flash to achieve this. If you try to use P-TTL on the main flash you will find the "dumb" flash will fire on the Pre-flash not the main one.

QuoteOriginally posted by Kombivan Quote
I must admit I have been envious of the crystal clear surf shots the nikon and canon guys get and I wonder why can't I get those shots?


Perhaps you can post some pictures that Nikon and Canon users can achieve that you cannot. You may receive some advice that can help.
11-15-2017, 10:44 AM   #45
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SURF SESSION PHOTOGRAPHY | Nutgraphics Nutgraphics

---------- Post added 11-15-17 at 10:45 AM ----------

some of ian's photo's are like glass on the lip of the wave.

---------- Post added 11-15-17 at 10:45 AM ----------

some of ian's photo's are like glass on the lip of the wave.
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