Half of every picture is black?

I hope you don't take this the wrong way. I'm trying to say this in a polite and constructive manner. There are a couple of people who do the same to me when I get out of hand (mostly Jay Turberville and Stephen Melvin, thanks guys).

You might want to read a bit more thoroughly, try to understand both the original question and other people's answers to it, before you post.

In this thread, reading the first three posts (Jeff's original question, Dave's request for more info, and Jeff's reply) would have told you why the original poster's experience with D70 left him confuser about D80 sync.

I've seen you similar things, fairly often recently.

http://forums.dpreview.com/forums/read.asp?forum=1021&message=20378999

You commented on variable aperture zooms. The original poster understood variable apertures, and noted that behavior in the viewfinder LCD. He was confused about the discrepancy between the viewfinder LCD and the top panel LCD. (Another poster in that thread came up with the correct answer, incidentally, that it's stray light through the viewfinder eyepiece).

http://forums.dpreview.com/forums/read.asp?forum=1034&message=20379519

This guy didn't want to know if his lens was a screwdriver drive, he wanted to know what he may have damaged, camera or lens, from a his short turning of the manual focus collar.

--
Normally, a signature this small can't open its own jumpgate.

Ciao! Joe

http://www.swissarmyfork.com
--
Normally, a signature this small can't open its own jumpgate.

Ciao! Joe

http://www.swissarmyfork.com

Sorry I could not get back in here sooner.

You said you are using a wireless sync. I have the same problem using mine as well and I use it with a Sunpak 544.

When I hook the Sunpak to my Wein safe sync on the hot shoe using a PC cord directly to the flash unit I can beat the shutter and shoot at any speed in manual mode, all the way up to 1/4000.

When I hook up the wireless, I can only shoot at 1/125. Aperture has no effect in any situation. There seems to be just enough delay in the wireless to cause the flash to fire after the shutter is on its way closed. This is the reason you are seeing the black on the bottom, with no ghosting in the dark area. If you see ghosting in the dark area caused by the shutter, then the flash is firing prematurely, but this is not the case and I have never seen this happen in a camera, film or otherwise.

Hope this helps you to understand.

--
John

http://www.eyeunit.com/

D50
18-55 AF-S ED 1:3.5-5.6
50mm f1.8D AF Prime
60mm f2.8D AF Micro
85mm f1.8D AF Prime
70-300mm 1:4-5.6D AF ED

SteveL54 said:

...
Here are some links to further information.

http://www.photozone.de/3Technology/flashtec4.htm

http://www.photozone.de/3Technology/flashtec5.htm

Steve

Click to expand...

Very good reference! Thanks for sharing that! I have always questioned how on earth the shutter works (does it flip, is it a curtain, etc etc)!

PS: a newbie in D-SLR as you can tell

--

There's more to being an engineer than just writing technical memos that nobody reads

SteveL54 said:

Why do you shoot at such high speed with your studio strobes?

If the studio strobes are your light source why not just set the
shutter speed down to 1/200s (or lower) and let the strobes stop
any action?

If you have ambient or continuous lighting which contributes to the
exposure I can see the need to keep the exposure short, but I'd
think your Alien Bees would be the dominant light source.

Steve

Click to expand...

The D80 seems to want to over expose a bit, and at 1/200 I cant shoot anything less then f14 it seems,

I am still learning the lights, and truthfully the whole f stop thing still confuses the hell out of me.

on the back of the bees there are markings, full, 1/2, 1/4, 1/8 etc.
I usually have the key at just under 1/4 and the fill at like 1/16
And still need the f14 at 1/200 to make sure its not over exposed.

First, check without the flash. If the problem still persist...

I had that on my Rebel. The problem is that the secondary mirror does not rise any more, blocking about 1/3 of the sensor.

In the rebel, the mirror is risen by a plastic pin. Mine broke...

Time to take your camera to a service center.

Sorry to break you the bad news.

d/n

Joseph S. Wisniewski said:

I hope you don't take this the wrong way. I'm trying to say this in
a polite and constructive manner. There are a couple of people who
do the same to me when I get out of hand (mostly Jay Turberville
and Stephen Melvin, thanks guys).

Click to expand...

First, you and I have seen eye to eye on some topics before, so we don't always disagree. Lately, I have been in a bit of a hurry at times I'll agree, and have snapped off a couple of answers. However, if you're going to analyze all my responses on these forums, which are plentiful, it would be fair to see how many times I really do provide helpful tips and advice. If you've found 3 cases where you think I'm off, that's not bad, IMO. I was reluctant to answer you here, but I will, so please don't try and turn everything I say around to suit your needs. I'll try to explain my rationale.

Joseph S Wisniewski said:

You might want to read a bit more thoroughly, try to understand
both the original question and other people's answers to it, before
you post.

Click to expand...

A lot of posts, while they have a main question, intimate some amount of knowledge that may be missing by an OP, or touch on a side issue. Sometimes I will notice that and answer a "sub point".

Joseph S Wisniewski said:

In this thread, reading the first three posts (Jeff's original
question, Dave's request for more info, and Jeff's reply) would
have told you why the original poster's experience with D70 left
him confuser about D80 sync.

Click to expand...

Let's look at the first 3 posts. Jeff first states that he has a problem where part of his picture is black, and is concerned that it could be a sensor problem. At this point he doesn't mention having used any other camera in the past, only his new D80.

In the second post, Dave offers some advice that he may have exceeded the maximum flash sync speed.

In the 3rd post, Jeff replies that he was indeed shooting at 1/320, over the 1/200 max sync speed for his D80. Yes, he mentions that he had used a D70 previously.

You've pointed out in this thread several times that the sync speed of the D70 is different from a classic definition of sync speed due to the nature of its partial electronic shutter. However, I would view that as the anomoly, rather than the other way around. Digital SLRs are relatively new compared to their "analog" counterparts, if we want to use that term. I'm not faulting Jeff000 here, but had he known how most other SLRs work, other than one with a partial electronic shutter like the D70, he may have tried to reduce his shutter speed to see if his problem went away, rather than "turned the camera around upside down turned it off and then on, took the battery out, and did what ever I could think of." His statement here indicates to me that he didn't understand what the sync speed really meant, and what would happen if he exceeded it.

Had I not written the subject line that I did, and if I had omitted the 2nd sentence in my reply, I don't think this would have hit a nerve for you. I'll admit I get frustrated at times and my editorial neutrality is strained (!). The bulk of my post was helpful I think, and explained in more detail exactly why one would get an unexposed area if they exceed the max sync speed.

Joseph S Wisniewski said:

I've seen you similar things, fairly often recently.

http://forums.dpreview.com/forums/read.asp?forum=1021&message=20378999
You commented on variable aperture zooms. The original poster
understood variable apertures, and noted that behavior in the
viewfinder LCD. He was confused about the discrepancy between the
viewfinder LCD and the top panel LCD. (Another poster in that
thread came up with the correct answer, incidentally, that it's
stray light through the viewfinder eyepiece).

Click to expand...

I'll agree with you on this one.

Joseph S Wisniewski said:

http://forums.dpreview.com/forums/read.asp?forum=1034&message=20379519
This guy didn't want to know if his lens was a screwdriver drive,
he wanted to know what he may have damaged, camera or lens, from a
his short turning of the manual focus collar.

Click to expand...

Look a little more closely on this one. The OP ended his post with this specific question: "This sigma lens has it's own focusing mechanism or uses the camera??" To me, this indicates that although he went on at length about forcing the focus ring, he still has a question as to whether the lens uses the screw drive or a SWM-like internal motor. I think my response was appropriate and to the point.

Anyway Joe, I hope this ends our little "friction" here. I'm not perfect, but I don't think anyone else here is either. Instead of trying to continue to pick on my answer on this particular thread, let's move on to share information with our other friends on the forums. Thanks!

when I read your message again I realize you are trying to tell me something "for my own good" in a "neutral" way . I think we're both similar in that we are very detail oriented and analytic, and strive for that ever-elusive perfection, which is sometimes a curse at least for me.

With the D70, were you using the higher shutter speeds to control exposure with the studio strobes?

In that case, once the D70 shutter speed exceeds the flash duration then the studio strobes start acting more like a continuous source of light. The faster your shutter the more you can open the aperture.

As you found out that is not practical with the D80's mechanical shutter. It seems you only have aperture, neutral density filters, ISO, and flash power settings to control exposure with the D80 with your lights.

I suppose you're already at ISO 100 and have the fill at its lowest power setting. Have you tried ND filters to cut the light so you can open up the aperture more?

Steve

Jeff000 said:

SteveL54 said:

Why do you shoot at such high speed with your studio strobes?

If the studio strobes are your light source why not just set the
shutter speed down to 1/200s (or lower) and let the strobes stop
any action?

If you have ambient or continuous lighting which contributes to the
exposure I can see the need to keep the exposure short, but I'd
think your Alien Bees would be the dominant light source.

Steve

Click to expand...

The D80 seems to want to over expose a bit, and at 1/200 I cant
shoot anything less then f14 it seems,

I am still learning the lights, and truthfully the whole f stop
thing still confuses the hell out of me.

on the back of the bees there are markings, full, 1/2, 1/4, 1/8 etc.
I usually have the key at just under 1/4 and the fill at like 1/16
And still need the f14 at 1/200 to make sure its not over exposed.

Click to expand...

Jeff000 said:

I dont get why it doesnt work though, i mean shutter speed is
shutter speed, the light gets their befor the shutter can close,
and to catch the shutter closed like that? i dont know.

Click to expand...

Jeff

I've stuck my 2 cents here as I believe this is the area of your misunderstanding re shutter speeds.

I had a quick read through the rest of the thread and there are some good responses. And a few good links I have bookmarked for future.

I think most misunderstanding starts because we call it 'shutterspeed' and somehow imagine that it is the speed of the shutter that varies. ie with say a 1 sec exposure the shutter open leasurly and closes one second later, and with a faster exposure say 1/1000 sec the shutter wizzes open and then snaps shutafter a thousandth of a sec.

Better to call it exposure duration. Because the shutter, that is the blades or curtains that make up the mechanism travel at a set speed, no slower or faster, whatever 'Speed' is set.

What happens in a 1sec exposure is the first curtain opens and one second later the second closes.

In the 1/1000 sec exposure the second curtain starts to close 1/1000 scecond after the first resulting in a 1/1000 sec duration slit moving across the sensor.

In a completely mechanical shutter the max flash sync is limited to the shortest duration that results in the sensor being completly exposed before the second curtain starts to close.

Select a 'speed' 'faster' than this and the second curtain will have started to close resulting in part of the sensor being covered when the flash fires.

Bob