Help needed please

thats your shutter you can see. If you are using eternal lighting you can see it because you're pushing past sync speeds. Else your shutter is on the way out
 
Thanks for that. I thought it must be something to do do with seeing the shutter, but I wasn't sure. I'll pass that on.
 
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They are flash lit shots, at 1/400th, 500th, 640th and 1/1250th of a second respectively. They've exceeded the sync speed. SLR cameras use a focal plane shutter. They work by having two curtains. Curtain one opens, and then curtain two closes. Due to physics, and inertia, the blades can only travel so fast, so on faster speeds the first curtain doesn't have time to fully open, before the second one needs to start closing, so on faster speeds, the two curtains actually travel across the film/sensor as a moving slit. This is what you are seeing here. The fastest speed the first curtain can open fully before the second one closing, is also the maximum speed that flash can be used as a result. This is the flash sync speed.

Certain dedicated flash guns allow sync as all speeds through carefully times pulses and and in some cases longer, lower power flashes... but generally, with most flashguns, you will have a maximum speed set by the physical properties of the shutter blades... usually either 1/200th or 1/250th of a second these days. Check your manual.

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Just seen you say that flash wasn't used at all. If this is the case, then there's a problem with his shutter.

[edit of edit]

Some of those shots have a very hard, sharp catchlight in the dog's eyes... very reminiscent of off camera flash. The meta data says "flash not fired" but manual off camera flash will report as no flash being used unless you're linked with a TTL cord.. You sure they are not flash lit?

If no flash was used.. external as well as inbuilt or on camera, then this is definitely a shutter problem. If off camera flash was used, then you've exceeded sync speed.
 
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OK, the images your friend posted there have the following EXIF data (in order, top to bottom):
1/400th at f/4, ISO 250
1/500th at f/4.5, ISO 640
1/640th at f/3.5, ISO 640
1/1250th at f/3.5, ISO 640
According to the EXIF, flash was not used.

So it is *not* an issue to do with flash sync, since there is no flash. But I think it is an artefact of the lighting, which is very similar. I think these photos were taken under some sort of artificial light source, like a fluorescent tube, which flickers very fast.

You'll appreciate that, for any shutter speed faster than the camera's flash sync speed (1/250th for the Canon 7D), th shutter is never fully open. The second curtain starts closing before the first one has fully opened, and at any given instant only a 'slit' is open. At 1/400th of a second, the slit is quite wide, so if there's a brief flash of light it will illumnate most of the sensor. But at 1/1250th the slit is narrow, so a brief flash of light will only illuminate a small part of the sensor. I think that's what we're seeing here.
 
Rats, must learn to type faster and avoid distractions!
 
Hmmm. The EXIF data says no flash was used. And to my mind the pictures don't look like flash was used - the lighting is too even, especially bearing in mind that this was with an ultra-wide angle lens. But it does look exactly like the effect you'd get with flash.

Are there any artificial light sources that flicker with such a high frequency?
 
StewartR said:
Hmmm. The EXIF data says no flash was used. And to my mind the pictures don't look like flash was used - the lighting is too even, especially bearing in mind that this was with an ultra-wide angle lens. But it does look exactly like the effect you'd get with flash.

Are there any artificial light sources that flicker with such a high frequency?
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There are.. but you wouldn't get a completely black stripe like that.

You can get flash to look natural you know.. :) It could be bounced off a white ceiling... that would look very similar.

This is simple... if flash was used, then clearly, as the meta data shows, you have exceeded sync speed. If no flash is used, you're shutter is ****ed :) Sorry.

However.... given that even the slowest speed used here was 1/400th, I would expect much more of the shot to be masked by the second shutter blade.

Probably time for it to go to the camera hospital :(... or the bin.
 
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Here's the thought experiment whch will settle it. Repeat the series of exposures (shutter speeds from 1/400th up to 1/1250th) outdoors in daylight. Black portions on image => shutter problem. No black areas => lighting artefact.
 
Yup. That will prove it. Although whoever took the shots will know if flash was used. If no flash was used... camera screwed. Simples :)
 
Pookeyhead said:
You can get flash to look natural you know.. :) It could be bounced off a white ceiling... that would look very similar.
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Fair point!

But ... surely bouncing flash manually off the ceiling, with no connection to the camera (hence no mention of flash in the EXIF), is hard work? These images all look very well exposed, except for the black bits of course, so presumably the exposure is not done with TTL metering. That really seems too much effort to go to, to get a few snaps of the dog.
 
StewartR said:
But ... surely bouncing flash manually off the ceiling, with no connection to the camera (hence no mention of flash in the EXIF), is hard work?
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Depends who you are, or your skill level I suppose. I'd find it as easy as blinking, but as this was someone on another non photographic forum... then you may have a point.

I never said with no connection though... I just meant a manual PC extension cord... i.e.. non TTL.

Looking like the camera s screwed.
 
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Pookeyhead said:
Do try to keep up :)

No flash was used apparently.
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i note you said apparently well i would say from these shots it was or else where is the shadow coming from in the first pic on the dogs foot?
 
dinorock said:
i note you said apparently well i would say from these shots it was or else where is the shadow coming from in the first pic on the dogs foot?
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Because the shutter has a physical fault?

If no flash was used... then what else can it be?
 
here you go "no flash according to the exif data but i can assure you this was taken in a studio if you use cheap radio triggers "like mine" no info has shown i would say all of the photos were taken using flash and as the shutter speed got faster the shutter covered more and more of the exposure. hth mike oh and i don't think theres anything wrong with the camera .....user error!!!


studio flash by Mike Rockey, on Flickr
 
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We all know that external flash with no TTL communication or hot shoe connection will record metadata as "No flash fired. Please don't patronise me :)

Incidentally... if you use the Pocket Wizard system with the AC3 to remotely fire your flashes (other brands of TTL wireless slaves are available :)) then it WILL record flash as being used. If you use the internal flash as a commander for remote TTL flashes like the Nikon CLS system uses, it can also record the flash as being used.

However... this is all pedantry.

The person who took the image though, says that no flash was used, so we can assume that he probably knows best.. So all we have to do is put this simple scenario to him:

"Was flash used?".

If the answer is no, then his shutter is faulty.

If the answer is yes, then he exceeded flash sync speed as his metadata corroborates.


That's kind of all there is to it really.
 
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If no flash was used, and I must take his word for it, then it is a shutter problem or possibly a slow mirror blocking off part of the sensor as the shutter passes across. ( a very rare problem).
More likely is that the the second blind is capping partway through the exposure ( I.e. catch up with the first blind during the exposure... also rare these days, as they are electronically controlled)
 
My guess is a shutter fault. Which is all it can be if no flash was used.

The black areas don't look right for a flash sync issue - not as sharply defined as I'd expect them, and the height of the black bands in the frame doesn't quite sit with the Exif shutter speeds.

Actually, I have seen a similar problem with a different answer - turned out the black band was actually the camera strap hanging over the lens.
 
he did use a flash gun ,,,,,,,,,
 
donut said:
he did use a flash gun ,,,,,,,,,
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Haha! So he did, an old Hanimex bounced, and not picked up in the Exif. Some folks around here are too clever for their own good :D :exit:
 
donut said:
he did use a flash gun ,,,,,,,,,
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LOL

Can you imagine if he'd dropped this off into Fixation as a fault and told them no flash was used? They'd have ripped the shutter module out by now :)

However......

Pookeyhead said:
Some of those shots have a very hard, sharp catchlight in the dog's eyes... very reminiscent of off camera flash. The meta data says "flash not fired" but manual off camera flash will report as no flash being used unless you're linked with a TTL cord.. You sure they are not flash lit?
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I hate doubting people.... but sometimes it clearly is justified. I think I'll go back to my default position of assuming everyone's thick... it's easier :)
 
So flash was used I, ll accept your apology quote " catch up" it was clearly a flash problem from the start but what do I know?
 
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We were told no flash was used. I voiced my suspicions that it might be, but operated on the assumption that the photographer knew whether he was using flash or not. Like I said, I'll go back to my usual MO of assuming idiocy. "try to keep up" was referring to reading the thread, not an inference that you don't know anything.
 
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You may well have been told no flash was used but looking at the photos it clearly was. I think sometimes we should look at the photos and stop listening to the people who clearly don't know what they are talking about :)
 
dinorock said:
You may well have been told no flash was used but looking at the photos it clearly was.
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Pookeyhead said:
Some of those shots have a very hard, sharp catchlight in the dog's eyes... very reminiscent of off camera flash. The meta data says "flash not fired" but manual off camera flash will report as no flash being used unless you're linked with a TTL cord.. You sure they are not flash lit?
Click to expand...

dinorock said:
I think sometimes we should look at the photos and stop listening to the people who clearly don't know what they are talking about :)
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Pookeyhead said:
LOL

I hate doubting people.... but sometimes it clearly is justified. I think I'll go back to my default position of assuming everyone's thick... it's easier :)
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So obviously no argument from me there :)
 
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