D70 and 1/4000 flash sync ?

this is a comment from another thread:

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Frank Skomial , jun 16, 2005; 01:18 a.m.

David,

Nikon D70 camera has professional quality CCD sensor, and as such has

also electronic shutter that is possible with CCD sensors. (D70 also

has mechanical shutter that does not matter for very high speed

sync.).

D70 has rated high sync max speed of 1/500 for all Nikon flashes. In

this case D70 recognizes a Nikon flash and will refuse to set shutter

any faster.

When you connect a studion strobe, a non-Nikon flash, the D70 sync is

no longer limitted to 1/500 sec. You can synchronize faster, all the

way up to 1/8000 sec, but the last 1/8000 value is less predictable.

All the way up to 1/4000 sec, is your range of full frame flash

synchro with flashes that D70 does not recognize as a Nikon flash.

I got successful shots with my monolights, and with Sunpak 555, all

the way to 1/4000 sec. I could not achieve this quality with FPmodes,

and any other camera.

This is why I call the CCD sensor a professional type sensor, and I

make some Canon users very angry. Lets face it, none of Canon DSLR

has CCD sensor, and Nikon D2x does not have it either.

For fast speed creative flash lighting the D70 is the only camera, no

matter the price.

(Not to confuse you any more, some cameras have stroboscopic mode FP

mode that causes uneven frame exposure by multiple consecutive

blasts, and a lot of distortion. This mode does not come close to the

quality of single flash blast at 1/4000 shutter speed.

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my answer:

i worked with almost any camera. phase one backs have ccds too but

they have no way to sync without a mechanical shutter. the fact that

the D70 sets the shutter time to at least 1/500 says that this is the

fastest time in wich the whole frame is lit by a flash.

the only way i can imagine is that the flash duration of some strobes

is longer than say 1/500 sec. if you shoot a frame with 1/4000 in

that time you have an completely lit frame. i doubt that you can sync

a shutter that precisely. and if thats possible it has nothing to do

with ccd sensors and should be possible with any camera.

some strobes have very fast flash durations. even more so flashes. if

you dial down an on camera flash you get incredibly fast flash

durations. so short that youll get reciprocity failure (ultra short

term) already. but that is too achieveable with any camera, including

a holga.

>This is why I call the CCD sensor a professional type sensor, and I

>make some Canon users very angry. Lets face it, none of Canon DSLR

>has CCD sensor, and Nikon D2x does not have it either.

i have never heard about a professional or non professional sensor. i

guess anything you can make money with is professional. if you are

talking about the quality of the sensor, id rather sync at 1/200 than

using it.

>For fast speed creative flash lighting the D70 is the only camera,

>no matter the price.

thats definitely not true.

anyone has other explainations ?

regards, David

David,

I deleted your earlier posting because, as I explained at the time, I thought it served no useful purpose. At least, this time around, you have appended a question so we'll see how it goes - but if the thread degenerates into a stupid Canon -v- Nikon thread it will be deleted.

There is a persistent myth, apparently initiated by Thom Hogan, that Nikon DSLR's have an electronic shutter on the sensor that syncs at higher speeds. I have contacted Nikon technical support who responded emphatically that this is not true.

There is only one shutter in Nikon DSLRs, a vertical, mechanical focal plane shutter with an electronic timer (hence the "electronic" reference in the sales literature. The sensor has an electronic gate which arms the sensor but does not serve as a shutter.

Like any focal plane shutter, the maximum sync speed for electronic flash is the maximum speed at which the shutter is completely open. At higher speeds, the leading and trailing blades form a slit less than the height of the sensor.

Certain Nikon flashes have an "fp" mode which have an extended discharge time, longer than the transit time of the shutter. Some studio flashes have a duration longer than 1/500 seconds, which is also longer than the transit time. In these examples, some degree of exposure is possible at any shutter speed.

Any electronic flash has a "tail" beyond the peak output as the hot Xenon cools which may be sufficient for an exposure. The after-light is not uniform with respect to time nor color.

Garry, i intendet to post my answer as a response but noticed the thread dissapeared. i assumed it was because i had not said anything in it.

for my part i dont care about brands.

Edward, this seems to be the information im talking about. i dont know if Frank Skomial has any pictures online made with that sync speed. that would be interesting.

maybe they were made the way i described above. ill try using a very long flash duration (hensel is famous for that, and i happen to have some of them) with a short shutter speed.

i once made some tests and the upper and lower part of the pictures were underexposed. but i dont know wich power setting i used.

i rent a D70 on friday to try it out myself.

regards, David

Hi everyone,

I think we could put this to rest pretty soon...with whatever explanation is the best.

This subject was discussed about 1/2 year ago, with description of camera/flash behaviour, but with no real proof of what is happenning there.

I discovered 1/4000 sync with 2 Monolights, each 1800 Wattseconds, and my original explanation was like yours, that surely the flash duration of those 2 monolight monsters must have been longer than 1/500.

Then I experimented with Sunpak 555, using vari power at 1/64 and at 1/32 of the fash power, and was getting correctly exposed frames at camera shutter set to 1/2000, 1/4000, and the EXIF value recorded by the D70 was exactly as set, that is 1/2000, or 1/4000. Flash duration of Sunpak 555, when varipower set at 1/64 is in range of 1/15000 of sec. This would not have exposed evenly entire frame via a narrow slot of focal shutter, even if the Xenon tube brightness was trailing well enough.

Then there were a dozen comments from other users who confirmed D70 ability to sync a single flash at 1/4000. General consensus was (possibly wrong ? - or not ?) that the electronic shutter of the D70 makes this possibly.

The bottom line is that D70 synchronizes non iTTL flashes at speeds up to 1/4000, that is many times faster than the max mechanical sync at 1/500. The real explanation how that is done, remains unclear. I hope this time we may get down to the true explanation.

I did not retain any test pictures, but they were clearly better frozen than pictures on my film camera with fast FP.

1/4000 sec? Well with my d70 and Pjillips 20B manual flash i can use 1/8000sec each time succesfully. It creates weird effects i.e. the view outside of a window is pitch black but the room is lit well even though its midday.

I may put pics up 2 prove it with freezing falling water droplets (cliched i know)

">For fast speed creative flash lighting the D70 is the only camera, >no matter the price.

thats definitely not true. anyone has other explainations ?

regards, David

"

David, you are asking anyone to provide other explanation that will please you. Seems that if you do not understand things, you tend to call them not true.

We are waiting for your verdict, since you intended to rent a D70 on Friday.

Good luck with your testing.

Frank

I have personally synced my D70 to a SB-600 and a Vivitar 283 at 1/8000 and 1/4000. I have used speeds up to 1/2000 in macro photography when I couldn't have a tripod and was in awkward postitions in windy conditions. <BR>

<BR>

<em>my answer: i worked with almost any camera. phase one backs have ccds too but they have no way to sync without a mechanical shutter. the fact that the D70 sets the shutter time to at least 1/500 says that this is the fastest time in wich the whole frame is lit by a flash.</em>

<BR><BR>

Flash sync is simply a term used to describe the fastest shutter speed that a flash pop will cover the whole frame. There is no requirement of a mechanical shutter at all to sync with flash, as the majority of point and shoot digital cameras prove. You've obviously not worked with large format leaf shutters, which can sync at any speed, or with the D70 and a non-dedicated flash, or electronic shutter point and shoots to make comments like these.

>Seems that if you do not understand things, you tend to call them >not true.

yes. if someone tells me that a camera syncs at 1/4000 with no explaination, well, its better to not believe until i proved it myself. i dont say you and the other people are wrong.

Scott, thanks i know what flash sync means. the fastest sync speed of the D70 is 1/500 sec. i have to say i never used a P&S camera but my 110 sekor as well as the large format lenses have leaf shutters, wich is pretty pointless in a discussion about focal plane shutters.

>There is no requirement of a mechanical shutter at all to sync with >flash,

thats true, but the shutter is actually a hindrance for the flash. the sync time is the time in wich the first curtain is fully opened and the second curtain has not yet started to close. on speeds faster than 1/500 (with the D70) the shutter is NEVER completely open. thus not the whole frame is lit by the flash.

do you know how much a rolleiflex lens costs that syncs at 1/1000 ?

if this camera is capable of synchronizing flash at 1/4000 nikon should advertise with it and have an explaination too.

but lets see, i open a new thread as soon as i have the results.

w.

Ok, totally manual flash and high shutter speeds do work with the D70

Here is an example

Unmanip'd and shot at 1/4000sec<div></div>

Edward - it's not a myth, and the information you received from Nikon service is just plain wrong. In another thread, I outlined a simple experiment (which I have performed in the past) that you can perform with nothing more than a computer with a decent sound card.

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00CaDT

Ciao!

Joe

jon noble, this example shows nothing. the shutter opens approximately 1/4 at 1/4000 sec. if your flash is long enough the whole image area is covered. this should work with any camera. the edges of the image are black, so underexposure would not be visible.

David

Joseph, you say that the mechanical shutter is fully opened at 1/4000. i have not done such tests but that is not possible, and not in such a low end camera anyway. and i doubt that you have metered the noise of the "electronic shutter".

does everyone know that hte sensor from the d70 is smaller than the image area of an n70 ? ok.

David

<blockquote><i>Joseph, you say that the mechanical shutter is fully opened at 1/4000. i have not done such tests but that is not possible, and not in such a low end camera anyway.</i></blockquote>

David,<P>

If you have a hybrid system you have to differentiate between the speed of the mechanical shutter, the electronic shutter and the combination of these two. The combination will always be the faster of the two. My guess is that the D70 mechanical shutter only exposes the whole sensor if it operates slower or equal to 1/250s, just as the sync speed of the other Nikons with a maximum 1/8000s sync speed.<P>

Electronic shutters are nothing new, they have been used in digital cameras before and have their advantages as well as drawbacks. Note that not all sensor types may have an electronic shutter. There are several types of sensors.<P>

But if you design your camera so that the mechanical shutter <i>never</I> operates faster than the sync speed of it (say 1/250s) this will mean that the whole sensor always will be exposed even if the <I>hybrid</I> (ie combination of the two) shutter is set to say 1/4000s. In other words, if you are, in this example, shooting faster than 1/250s the electronic shutter would be responsible for doing the "shuttering".<P>

<P><HR><P>

I will try to settle this once and for all. I am going to try this myself. I have owned a D70 for over a year and never needed synching as fast as this. I have read about this a number of times and accepted it as people I know from Swedish forums have reported this. Time to do a test. Please wait a moment...<P>

Thanks for waiting :-) Using a Wein Hot-shoe-to-hot-shoe Safe Sync I attached a SB-800 to the D70. The Wein doesn't have the extra contacts the SB-800/D70 has and thus the D70 has no idea that a flash is attached.<P>

The ambient light in the room was so low that the camera suggested 1/30s @ f/2. I set the camera to manual mode (1/8000s @ f/2.8). Without the flash the frame was completely dark. Adding the SB-800 and setting it too to M (1/128 power) I got the result below. If you want the full size JPEG/NEF please mail me. Stupid as I am I deleted the dark frame photo. But I have a small image taken using my compact digicam showing the D70 and SB-800 displays with the settings if someone distrusts me.<P>

According to the manual of the SB-800 the flash duration at 1/128 power is 1/41600s which would rule out the possibility of a long flash pulse affecting the result.<P>

What you see is the full frame of the image and not a crop. Original EXIF-information is present in this reduced version.<P><div></div>

By the way. You don't have to use a Wein like I did, I just happen to have mine in the camera bag for connecting to the studio strobes, so it was convenient (in fact it was the first time I used the hot shoe on it).

You can put electricians tape (I am not sure if that is the correct name in english, sorry), or any non-conductive tape over the two contacts in the back of the hot shoe. See the attached image. I have tried the experiment again and I have all the images now, including the black one, if someone really badly wants to see them.

Just for the record, I do not find this "sync-at-any-speed" feature with the D70 especially useful (YMMV), these tests were just done to satisfy my curiosity.<div></div>

Bah! Never write anything on an empty stomach. I dropped a paragraph to this:.<P>

<BLOCKQUOTE><I>If you have a hybrid system you have to differentiate between the speed of the mechanical shutter, the electronic shutter and the combination of these two. The combination will always be the faster of the two. My guess is that the D70 mechanical shutter only exposes the whole sensor if it operates slower or equal to 1/250s, just as the sync speed of the other Nikons with a maximum 1/8000s sync speed.</I></BLOCKQUOTE>

What I meant and I believe Joseph also meant was that when writing 1/4000s and 1/8000s we mean the shutter speed of the whole shutter system (ie hybrid shutter), not the actual speed of the mechanical shutter sub-system. The mechanical shutter on the D70 seems to <I>never</I> go beyond 1/250s or whatever value it has for exposing the whole sensor.<P>

<HR>

There is also the question to why the D70 doesn't want to sync faster than 1/500s with dedicated flash units. I can see two explanations, the first is the marketing one, it would be too "comepetent" and steal interest from the higher end cameras not having this "feature".<P>

The technical explanation would be that some flash pulses might be quite long (full effect on the SB-800 has a duration of 1/1050s) which could give unexpected results if you expose without having the full flash pulse to light the subject (say when shooting at 1/2000s and the flash is set to full output). The camera has no possibility to know how long each flash pulse might be from all kinds of dedicated flashes that are manufactured.<P>

To prevent the support department from getting hundreds of calls from people not knowing the limitations and being upset with getting inconsistently exposed photos they have simply prevented it to work. (Hmmm... Perhaps sometime in the future the flash can communicate this information to the camera and allow the automatic system to take it into consideration. Well, I said it out loud, now nobody can patent the idea.)<P>

Or it may be a combination of both. Note that this is just me guessing. I have no insight into the technical or marketing departments of Nikon (nor any other camera manufacturer).<P>

Why doesn't higher end bodies from Nikon have this feature? Probably they use another sensor type. From what I understand, sensors having electronic shutters loose surface area due to the light shielded registers needed for the electronic shutter. Sometimes you want to use as much area for your photosites. Again, only Nikon may properly answer to this design question. This <A HREF="http://www.electronicproducts.com/ShowPage.asp?SECTION=3700&PRIMID=&FileName=KODAK.feb2004.html">article</A> has some information on different sensortypes.<P>

Anyone that has additional information on sensor types are welcome to mail them to me or share them in the forums.

Max, thanks alot !

these pictures show what i wanted to see.

i had the d70 but no safe sync. i didnt want to destroy someone elses camera.

the reason this is not used in other cameras is simply, its not necessary. its just fun to see that its possible. just if you want to shoot with f 1,2 in bright daylight and want a totally black backroung then yes you need that feature !

shurely it wouldnt be wise for nikon to permit this speed for normal flash use.

David

I'm confused? why wouldn't nikon want this to be a feature? Why is it any less necessary than any feature?

allan

David altmann

Im condused how can a shutter be open for only 1/4sec at 1/4000sec.

There was no black edges in the pic (i know what they look like as a OM10 doesnt work with flash above 1/60 which i found out after a few rolls and the internet)

Here is another example

1/3200sec and no crop. There is no black sections<div></div>

>I'm confused? why wouldn't nikon want this to be a feature?

because normally at 1/500 everything is pretty black. at 1/1000 everything is pretty completely dark, at 1/2000 everythinf is damn dark. see the difference ?

there are even people that shoot pentax 6x7 wit a maximum sync time of 1/30. and i heard the make ok photos too sometimes.

and speeds faster than 1/1000 are not as easy to handle because of the ultra short term effect. exposure doesnt drop linear. like an reversed schwarzschildt.

>Why is it any less necessary than any feature?

necessary features are: light tight box, apperture, shutter, focussing. thats all you need. so i regard most features as useless. (and no im not a minimalist but thats simply what most pros use anyway)

Jon, i didnt mean 1/4 sec i meand the shutter is opened 1/4 as in a quarter.

David

<p><i>because normally at 1/500 everything is pretty black. </I>

<p>And my point is that it's perfectly reasonable that one might want a black or nearly black background in a flash situation, outdoors, to simulate night or something like it. it can be a creative effect, which makes it just as valid as just about any of the other features a camera offers (even the inclusion of multiple shutter speeds and apertures).

<p><i>there are even people that shoot pentax 6x7 wit a maximum sync time of 1/30. and i heard the make ok photos too sometimes.</I>

<p>well, golly gee, you don't say? While I realize you may have taken my questions as being rife with attitude, they were not. I was honestly confused about why you were saying what you said. No need to be sarcastic and condescending in return.

<p><i>necessary features are: light tight box, apperture, shutter, focussing. thats all you need. so i regard most features as useless. (and no im not a minimalist but thats simply what most pros use anyway)</i>

<p>that's weird. I know lots of pros that make use of creative features such as high sync speed. And while you may choose to regard them as useless, it doesn't mean that they are. I know people who don't use autofocus or light meters too.

<p><i>Jon, i didnt mean 1/4 sec i meand the shutter is opened 1/4 as in a quarter.</I>

<p>And I think Jon pretty effectively answered that question with his second example photo. That shutter is open all the way on that one. Plus, if that first example were open only 1/4 way, how would that 1/4 have been in the middle...?

<p>allan

>And my point is that it's perfectly reasonable that one might want a >black or nearly black background in a flash situation, outdoors, to >simulate night or something like it.

yes, but my point was that you can achieve that with 1/500 already and you dont need to sync at 1/4000 for that.

>well, golly gee, you don't say? While I realize you may have taken >my questions as being rife with attitude, they were not. I was >honestly confused about why you were saying what you said. No need >to be sarcastic and condescending in return.

i dont like the pentax 6x7. i find a max sync time of 1/30 is ridiculous. but there are still very good pictures made with that camera. so it was meant to be fun to show that there are cameras with such a slow sync speed that still produce good results. i did by no means try to be condescending.

>that's weird. I know lots of pros that make use of creative features >such as high sync speed. And while you may choose to regard them as >useless, it doesn't mean that they are. I know people who don't use >autofocus or light meters too.

of course its cool to photograph the moon with a 8000mm lens but its more interesting to be there and shoot pics on the moon with a... light tight box. not really a good example maybe.

>And I think Jon pretty effectively answered that question with his >second example photo. That shutter is open all the way on that one. >Plus, if that first example were open only 1/4 way, how would that >1/4 have been in the middle...?

yes in the case of the d70 there seems to happen something else. if you use most other cameras with strobe at 1/4000 only about 1/4 of the picture will be exposed correctly or at all.

David

It seems to be a fact that whenever photographers express their views there's bound to be some dissent...

Dissent is healthy but please be courteous - on this forum, if you want to play you have to play nice

That is what this thread is.

It is possible to get up to 1/8000s sync with the D70 and an appropriate flash.

I use flash sync of 1/2000s routinely. No magic and all real.

Garry, i just happen to speak more german than english. so maybe i come across as impolite sometimes but its not intentional. ill try my best. thanks for posting to anyone.

David