Why is exposure time limited to a maximum of 30 seconds?

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Stephen
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Have started to play around with long exposures and wondering why the built in exposure time is limited to a maximum of 30 seconds. Would be good not to have to rely on bulb mode and a remote. Anyone know the answer? And if any camera allows for longer exposures?

Stephen
 
Some Panasonics do 60 seconds, is there a remote app for your phone which would allow longer, otherwise buy a remote release, usually generic usb ones work on modern cameras. I shoot a lot of long exposures and the remote release just becomes second nature, one advantage is that you can alter the exposure time should the light levels change without physically touching the camera causing potential shake.

Much cheaper to buy a £10 release than change the camera!!!
 
Because there has to cut off point somewhere otherwise you could find yourself scrolling forever to reach the figure you needed far easier just to set a reasonable limit and then move to bulb, as an aside the Olympus seem to go up to 60 seconds too
 
It maybe to do with the fact that time exposures use more battery than short exposures.

If the battery went flat with the shutter open it may knacker the camera?

Dunno, it's a thought.
 
The Pentax K-1 goes up to 20 minutes in bulb mode.

Why there isnt a menu option in every camera to set any time you like has always baffled me!
 
Back in the good old days as well as B (Bulb) we also had T (Timer) first press shutter opens, next press shutter closes, I wouldn't have thought that would be to difficult to implement in the software on a modern camera.
 
Jannyfox said:
I guess the number of users wanting an exposure length of more than 30 sec is limited and it has to stop somewhere. What's wrong with a remote release?
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Agree. Exposures longer than 30 secs are easy to time accurately by hand, and the Bulb setting is easy to access - a separate setting on the mode dial with no need to scroll through endless speeds. Also, on Canon at least, in Bulb mode the frame counter counts up in seconds so you don't need a timer or watch.
 
I wonder if it's anything to do with noise adjustment. There has to be a point where the image quality deteriorates with or without correction.
 
HoppyUK said:
Agree. Exposures longer than 30 secs are easy to time accurately by hand, and the Bulb setting is easy to access - a separate setting on the mode dial with no need to scroll through endless speeds. Also, on Canon at least, in Bulb mode the frame counter counts up in seconds so you don't need a timer or watch.
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Nothing via the mode dial on my camera. I do have to scroll through everything, but it does have the timer, however use an intervalometer and you don't even have to look at the screen as it counts.
 
Jannyfox said:
Nothing via the mode dial on my camera. I do have to scroll through everything, but it does have the timer, however use an intervalometer and you don't even have to look at the screen as it counts.
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Yes, looks like the separate B mode is only on the upper range Canons, worth noting for anyone that does a lot of long exposure photography.

This is the kind of timer unit I use, and I think most other folks too - bargain at a tenner. Available under loads of different over-brand names in a wide range of camera fittings* and there's also a radio-remote operated version https://www.amazon.co.uk/Neewer-Shu...89666958&sr=1-2&keywords=remote+release+timer

*Note that several manufacturers use different remote plug fittings for entry-level cameras and higher-end models.
 
mike weeks said:
This is not a digital limitation, just looked back at some specs and the increase to 30 secs from a Nikon view may have happened in 1996 with the arrival of the F5 (F4 from 1988 had 4 seconds) and they probably never saw a sensible reason to increase it.

Mike
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Long exposure photography over a few seconds is really a digital invention that is pretty much non-existent with film cameras - either extremely difficult, and in black & white only, or simply impractical.

The problem with film is 'reciprocity failure' at longer shutter speeds. At low light levels, film needs disproportionately more exposure, eg a digital exposure of say 10 seconds may need 60 seconds with film, and it gets progressively worse. Furthermore, the different layers of colour film have different reciprocity characteristics and so you end up with uncorrectable colour shifts.
 
HoppyUK said:
Long exposure photography over a few seconds is really a digital invention that is pretty much non-existent with film cameras - either extremely difficult, and in black & white only, or simply impractical.

The problem with film is 'reciprocity failure' at longer shutter speeds. At low light levels, film needs disproportionately more exposure, eg a digital exposure of say 10 seconds may need 60 seconds with film, and it gets progressively worse. Furthermore, the different layers of colour film have different reciprocity characteristics and so you end up with uncorrectable colour shifts.
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Tell that to Michael Kenna!!!.....
 
There was, initially with digital, a problem with sensors getting hot with longer exposures. The result was an image which was worse than reciprocity failure.

RF was an overall issue which affected the whole emulsion. Digital sensors, however, suffered hotspots with patchy discolouration and overexposure. Maybe less of a problem today but, traditions are sometimes hard to break! 30secs is as good a point as any to be a cut-off.... 30 secs is just about the limit for arresting star-trails.
 
GreenNinja67 said:
It maybe to do with the fact that time exposures use more battery than short exposures.
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Yes. The exposure is using processor and sensor power plus, with a magnetic lock shutter, running power through a coil. This drains the battery a lot and the designers have to decide how to handle that. Setting a figure they think will work for most people is the practical compromise.

HoppyUK said:
Long exposure photography over a few seconds is really a digital invention that is pretty much non-existent with film cameras
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Wrong in every way. I used to work regularly with exposures in the range 5 to 30 minutes and astronomers often used (and probably still do) exposures running into hours.
 
Sejanus Aelianus said:
Wrong in every way. I used to work regularly with exposures in the range 5 to 30 minutes and astronomers often used (and probably still do) exposures running into hours.
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Correct.

I remember reciprocity failure rather well, you could even use it to your advantage if you knew your emulsion inside out.
 
Sejanus Aelianus said:
astronomers often used (and probably still do) exposures running into hours.
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I have a few 35mm astronomical images taken around 40 - 45 min. Autoguiding hadn't been invented either - probably accounts for some of the joint problems I have now............... Finding the right film was always a problem as you'd find one that worked well, then the manufacturer would 'improve' it (for daylight use) and change the long exposure characteristics. I'm so glad technology has moved on :) Now you build up the exposure with multiple shorter ones.
 
Sejanus Aelianus said:
Yes. The exposure is using processor and sensor power plus, with a magnetic lock shutter, running power through a coil. This drains the battery a lot and the designers have to decide how to handle that. Setting a figure they think will work for most people is the practical compromise.
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Battery drain is exactly the same in B mode.

Wrong in every way. I used to work regularly with exposures in the range 5 to 30 minutes and astronomers often used (and probably still do) exposures running into hours.
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Please read what I said, and don't quote only half of it. To repeat: "Long exposure photography over a few seconds is really a digital invention that is pretty much non-existent with film cameras - either extremely difficult, and in black & white only, or simply impractical."

So not wrong then ;)
 
Sejanus Aelianus said:
As arguing with people who don't understand the subject is pointless, I'm simply going to put you on ignore.
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It would be much more helpful if you could try to explain why he is wrong, for the benefit of those of us who don't understand the electronics, instead of slapping him down. As a layman I'm seeing one person with one opinion and one person with a different opinion - how am I supposed to know which is right?
 
Sejanus Aelianus said:
Showing that your understanding of electronics is defective.
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Don't take my word for it then, research it. But as a clue, why is it that manufacturers remind you to only clean the sensor with a well charged battery? Because the open shutter is always drawing power and will close if the battery drains unexpectedly.

Yes, wrong then.

As arguing with people who don't understand the subject is pointless, I'm simply going to put you on ignore.
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Judging by some of your other recent posts, I expect to join a long and distinguished list.
 
Long exposure photography was used by the founders of photography if I'm not mistaken?

Ergo short shutter speeds are a modern invention.

Fox Talbot's "window" shot was I believe in the order of 20 minutes or longer.
 
Sejanus Aelianus said:
Yes. The exposure is using processor and sensor power plus, with a magnetic lock shutter, running power through a coil. This drains the battery a lot and the designers have to decide how to handle that.
Click to expand...

Processing only happens post exposure, sensors are really low powered, which leaves you lock, it is however monitor use that really drains power. So B mode would drain very similar if not the same for a shutter speed controlled 30 second exposure
 
StewartR said:
It would be much more helpful if you could try to explain why he is wrong, for the benefit of those of us who don't understand the electronics, instead of slapping him down. As a layman I'm seeing one person with one opinion and one person with a different opinion - how am I supposed to know which is right?
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Stewart, he's wrong on the shutter not drawing battery power in B mode question, but on the reciprocity failure thing we actually agree - I never said that long exposures and astro photography were impossible with film (which would obviously be ridiculous). I simply said that with film it is "either extremely difficult, and in black & white only, or simply impractical." Which is true. Question: why didn't we use ten-stop ND filters with film cameras? Because a) they were extremely hard to use due to reciprocity failure, and b) hardly anyone actually bothered to make them.
 
mike weeks said:
Processing only happens post exposure, sensors are really low powered, which leaves you lock, it is however monitor use that really drains power. So B mode would drain very similar if not the same for a shutter speed controlled 30 second exposure
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Except that in "B" the timer is inoperative.

With an auto exposure of 30 seconds the camera's timer is working, therefore using more battery I would guess.
 
StewartR said:
It would be much more helpful if you could try to explain why he is wrong, for the benefit of those of us who don't understand the electronics, instead of slapping him down. As a layman I'm seeing one person with one opinion and one person with a different opinion - how am I supposed to know which is right?
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I know from your posts that you certainly do know what you talk about. Perhaps you have the patience to put us both right where we're wrong but I lack that patience.
 
HoppyUK said:
Question: why didn't we use ten-stop ND filters with film cameras? Because a) they were extremely hard to use due to reciprocity failure, and b) hardly anyone actually bothered to make them.
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Mainly because film stock was 2 ISO (Sorry, ASA)

Why do you think Victorian Portrait studios had clamps to hold the victim's (again, apology - sitter's) head still? Anything to do with a long exposure?

I think what you meant to say it was difficult to time the shutter for long exposures, and that with the advent of Electronic cameras (not digital) it's a recent thing.
 
There was a formula I used to use for colour print film although I've forgotten it now.

I tried long exposures with Kodachrome 64 once....................

With hilarious results.
 
chuckles said:
<snip>

I think what you meant to say it was difficult to time the shutter for long exposures, and that with the advent of Electronic cameras (not digital) it's a recent thing.
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LOL No, I didn't mean to say that. I meant to say exactly what I did say ;)
 
mike weeks said:
Processing only happens post exposure, sensors are really low powered, which leaves you lock, it is however monitor use that really drains power. So B mode would drain very similar if not the same for a shutter speed controlled 30 second exposure
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When I talked about processing I was referring to the microprocessor clocking away, receiving data from the sensor and storing it in the buffer, not post exposure processing. Whatever the draw current of the sensor, the whole chain needs to be active, like any other computer. Monitors don't use that much power themselves - the backlighting is the big draw there. Mechanical shutters in digital cameras use some kind of latching to stay open, often a magnetic coil arrangement and that draws a fair amount of current.

You're quite right that a 30 second bulb mode exposure will use much the same amount of current as a 30 second auto exposure but the whole point is that it uses current and the designer has to decide on the trade offs he wishes to use between functionality, cost and power drain. There will also be less obvious trade offs to be made, such as heat generated by the electronics generally which is cumulative. The designer has to decide how much heat the assembly can be allowed to generate against the heat sink capability he wishes to build in.
 
HoppyUK said:
LOL No, I didn't mean to say that. I meant to say exactly what I did say ;)
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I'm so glad you live in your world of emperical dreams then - because I've tried to make sense of what you wrote and I can find none :(

We've always that reality of being able to use long exposures; it didn't occur with the advent of digital cameras! Even the quote you originally challenged was stating Nikon F4/F5 with 4 sec shutter speed (which I consider as being a few seconds).

Why no Big-Stoppers? Mainly it's a modern phenomenon of wanting 'milky' waterfalls etc. of yesteryear

I'm happy in my world thanks and I think it's not a lonely place ;)
 
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