D7100 focus issues

Pistnbroke

"[url=http://e-group.uk.net/gallery/showphoto.php/photo/81099][img]http://e-group.uk.net/gallery/data/500/HIL_yn565.JPG[/img][/url]" This is an image on a wall from the YN 565 at 10ft and is about 18 inches across.

Well I dont have any Nikon guns but on the YN565Ex its a solid state lazer (I have worked with lazers since the early 1970s) On the YN 465 its a led and is weak and missaligned with the centre sensor.
Your cable idea is great IF it does not lock out the auto iso AND if it works with the flash gun turned off .
If someone has got one let us know and look at the pattern on the wall by preventing focus by putting your hand over the lens.What we have is a version of trying to focus on a white flat wall and as you know it wont.
What this requires is replacement of the white focus assist led on the camera with a lazer that works during auto focus at any light level not "low light" .We need a target on low contrast images so it can focus. But I fear we must struggle on without help from Nikon.

PS tested a SC29 AF will not work without a flash gun and if the gun has AF built in the AF on the SC29 does not work

Ironheart

There is a switch on the SC-29 to signal the AF assist on the speedlight not to fire. I figured you were already using a cord anyway with your flipper. You can have the flash on, only to paint the hash pattern but not fire.

Pistnbroke

Ironheart ..do appreciate your persistance but the devil is in the detail ( I phoned a supplier who tested the cable for me ..but that was over the phone )
just to clarify what you say..
There is a switch on the SC-29 to signal the AF assist on the speedlight not to fire.
Do you therefore mean the one on the SC 29 works alone? How do you stop the flash fireing??

You can have the flash on, only to paint the hash pattern but not fire.
Is this a feature of the SB 910 (which I dont have) or a feature of the cable switch?

What I need is an AF illuminator that works when the camera is trying to focus and then switches off and no flash.
We must of course still have the auto iso working ....

Ironheart

The whole point of the SC-29 (and I own one BTW) is to allow you to move your flash off-camera and keep the AF assist grid shooting straight off of the hot shoe on the top of the camera. There is a switch on the SC-29 on the flash end of the cord, that is labeled "AF-ILL" and two positions, on and off. What this does is send a signal to the speedlight to tell it to turn it's AF assist on (or not).

How you disable your flash from actually firing but still being turned on and enabling the AF assist lamp, is flash dependent. The SB900 has an explicit setting, the SB700 you have to do a trick: set the in SB-700 in commander mode, then turn off the flash by switching the master channel (M) off (double dash)

Yer a smart guy, so you can figure out the equiv for your Yongo ;-)

I think this gets you what you want

Pistnbroke

All good but how is this affecting the auto iso ..??
I treat my camera like an M16 pull the trigger and it fires ..I dont piddle with the sights before each battle .

Photobug

@Ironheart is right, the SC-29 is an excellent option. Used it for years on multiple cameras.

Pistnbroke

Thanks photobug but does the auto iso still function with the SC 29 whilst it fires its AF beam? If so we have cracked it ....

heartyfisher

Thanks photobug but does the auto iso still function with the SC 29 whilst it fires its AF beam? If so we have cracked it ....

would like to know too ..

Also does a flash need to be connected for the SC29 to work? eg: can I use it on a Df and use it for better AF in the dark places or do I need the SU800?

Pistnbroke

Well progress is made " you are a smart guy and can figure it out"
(now how to prove that !!!)
If I put the Yn565 into S1 mode (slave) it emmitts a pulsed beam from its AF Lazer all the time its ON (not in the instruction manual) ..so a bit of plastic under its foot makes it think its not on a camera and you have your beam...does not seem to show even close up on a white wall....

Have ordered a SC29 so we will find out ( or re sell it)

Ironheart

I was 99.44% sure that this setup would give you what you want. Now I'm 100% sure, 'cause I just tested it. Using the SC-29 mounted on my D7000 camera, and the flash on a flipper, I disabled the flash output on my SB-700 as described above ("master" made sure channels M, A & B were set to --- ). Placed the AF-ILL switch on the flash end of the SC-29 in the "ON" position. In manual mode, the AF-assist grid shoots from the top of the camera SC-29, the flash is silent. Took a pic of a blue and black dress in the dark, camera shot at 6400 ISO (auto-ISO) at F/5 1/640 just like I told it to in M mode. In A mode it happily took a pic at any ISO or speed the fixed A would allow. It also only fires the AF-assist grid when it is too dark to focus without it, and it only lights it up while acquiring focus; as soon as it locks, it turns off.

How all this will work with your Yongnuo is TBD. I suppose it depends on how well they reversed-engineered it.

Photobug

@Ironheart - thanks for checking this out for us. We have the grand kids and I have no time to check it out. Nicely worded message.

Pistnbroke

I have one on order so any potential buyers hang on till monday.
I am pleased to hear it works at all iso as I have only been able to get the white assist light and assist on the flash to work at over ISO 4500...Ideally I would like it to work with my Meike MK 300 or no flash at all but we will see ,,,,

Waiting for the delivery man !!!!!

Pistnbroke

Oh what a sad day.....The SC 29 arrived but whatever I do I cannot get the AF illuminator to come on . The white AF comes on ...normally when a flash is connected with a AF illuminator the white lite does not fucntion being transfered to the AF illuminator in the Gun....works as a remote cable but nothing else ..I am concluding that the power for the AF illuminator built into the cable comes from the two pins which connnect to the brass connectors under the flash . None of my flashes have these ..but a Meikie 910 does..time for more thinking!!!

I think there is a furthur complication .Nikon improved the flash system on 7100 ( to match Canon) onwards to lock the iso at 4x the base iso when the flsh was turned on (not in inst manual) .....previous to this the iso wandered up and down and the flash was added . Hence the cable does not behave the same on a 7100 as it does on a 7000..my head hurts.

I think there is not a device made that does what I want ..fires an AF assist at ALL times the camera is trying to focus irresspective of lighting conditions.
The only question/way forward is ....do the two contacts near the flash shoe have a voltage across them every time the camera tries to focus ..need someone with a voltmeter.....

heartyfisher

..fires an AF assist at ALL times the camera is trying to focus irresspective of lighting conditions. ...

Let us know if you find one .. I have been looking for one too ... have you looked at the SU800 and Debao Clones (based on the canon version of the SU800) ?

Ironheart

Oh what a sad day.....The SC 29 arrived but whatever I do I cannot get the AF illuminator to come on . The white AF comes on ...normally when a flash is connected with a AF illuminator the white lite does not fucntion being transfered to the AF illuminator in the Gun....works as a remote cable but nothing else ..I am concluding that the power for the AF illuminator built into the cable comes from the two pins which connnect to the brass connectors under the flash . None of my flashes have these ..but a Meikie 910 does..time for more thinking!!!

The AF-assist illuminator on the SC-29 draws power from the flash via the brass connectors on the flash, as there is no power to be had at the hot shoe. I didn't think to ask you about that since all of my flashes have that connector. The white AF-assist lamp will only be disabled when the camera senses that the AF-assist on the flash is firing. Think of the SC-29 AF-illuminator as a remote illuminator from the flash, having nothing to do with the camera and you have the right mental model.

I think there is a furthur complication .Nikon improved the flash system on 7100 ( to match Canon) onwards to lock the iso at 4x the base iso when the flsh was turned on (not in inst manual) .....previous to this the iso wandered up and down and the flash was added . Hence the cable does not behave the same on a 7100 as it does on a 7000..my head hurts.

The flash on my D7000 behaves exactly the same way, so does the D800, and almost every other Nikon I've handled, which is that in Manual mode, when Auto-ISO is enabled, and a hot-shoe flash is connected and turned on, the ISO is locked to 4x the fixed ISO value. The good news is that when the flash output is disabled via the trick I mention above (or using the option on a SB-9x0) the camera knows the flash will never fire and goes back to non-flash Auto-ISO behavior. Neat huh??
This is what the manual says, not very clear:
Note that ISO sensitivity may be raised automatically when auto ISO
sensitivity control is used in combination with slow sync flash modes (available with the
built-in flash and SB-900, SB-800, SB-700, SB-600, and SB-400 flash units), possibly
preventing the camera from selecting slow shutter speeds
(This is page 104 in the D7000 manual, and page 82 in the D7100 manual)

I think there is not a device made that does what I want ..fires an AF assist at ALL times the camera is trying to focus irresspective of lighting conditions.
The only question/way forward is ....do the two contacts near the flash shoe have a voltage across them every time the camera tries to focus ..need someone with a voltmeter.....

The AF-illuminator only fires when there is not enough light to otherwise focus. Why would you want it to fire unnecessarily? That seems illogical to me. Yes, this is what happens, the flash would normally fire it's own AF-illuminator, but senses the load on the contacts and fires the SC-29 instead, I checked with my voltmeter.

Pistnbroke

I think the problem is missunderstood ...its not a dark issue ...say I am at a wedding reception speeches in progress ..well they dont do that in the dark do they ....a guest 25 ft away starts laughing so I spin onto her and the thing just wont focus ...similar with people on the top table ...loads of soft diffused light and lots of white maybe back lit ,,,
Seems to be lots of complaints on the internet about reluctance to focus
Reluctance to focus in church seem to be at ISO 2500 f8 1/60 no flash or similar figures for ISO

manhattanboy

Did you get a chance to try a lens with a wider aperture?

Pistnbroke

spent more time researching and it looks like general discontent with the D7100 focus system particularly amongst bird photographers who have moved from D7000 ( which is what I did) I guess the 4800 system on the 7000 has been cheapened and called 3500 ,does not work as well and is now getting a slow upgrade.Some saying with 7000 8/10 photos in focus and with 7100 2/10. So I conclude nothing to be done but will try the IR light and try to thow some invisible shadows to improve contrast..still waiting for the diodes. Really needs nikon to do a firmware mod to bring in the AF assist at 800 ISO as a menu option.
Sent back the SC29 as whilst the AF works (or can be made to work) the camera only activates it at iso 4500 and thats too high to be any use. Nikon seem to want to improve the AF in the dark when its not good in normal room lighting.
This has got me quite upset with Nikon....I spent good money to buy newer equipment that does not work as well as the old and most important to which I do not see a solution. The D800 is also the worst camera I ever bought ..I call it the senile camera no proper memory banks...
Sold me 5 year old Nissan and bought the latest one .same model ..not as good as the old one .Not happy with Nissan either.
Bad week