Home · Register · Software · Software · Join Upload & Sell

Moderated by: Fred Miranda
Username  

  New fredmiranda.com Mobile Site
  New Feature: SMS Notification alert
  New Feature: Buy & Sell Watchlist
  

FM Forums | Sony Forum | Join Upload & Sell

1
       2       end
  

Why do most cameras only go to 30s exposure
  
 
johnahill
Offline
• • • •
Upload & Sell: On
p.1 #1 · p.1 #1 · Why do most cameras only go to 30s exposure


I was out using my A7r the other day and was using bulb for long exposure images.
It's not the most friendly mode, the light level is dropping and I have an ND filter on, so to check exposure I remove the filter, go to Aperture priority, get a reading and recalculate for the ND then set back to bulb mode.

Why cant we have cameras that have exposure timer up to say 8mins? Or even just the metering function to show long exp times?

I know medium format and a few others have this but with my time with Canon, Fuji and Sony cams none have the facility to go past 30s.





Jan 03, 2018 at 04:59 PM
82DMC12
Offline

Upload & Sell: Off
p.1 #2 · p.1 #2 · Why do most cameras only go to 30s exposure


Good question, but it seems to me that if I have Live View Setting ON, and I use 30 seconds with an ND filter attached, that the actual exposure doesn't necessarily look like the viewfinder suggested it would at that long exposure time. I suppose the camera would have a tough time adding all that gain to the viewfinder image to give you a true idea of what to expect? You would be starting out from almost no visible image from which to apply the gain to.


Jan 03, 2018 at 06:00 PM
ZachOly
Online
• • • •
Upload & Sell: Off
p.1 #3 · p.1 #3 · Why do most cameras only go to 30s exposure


Because then they couldn't sell you a intervalometer


Jan 03, 2018 at 06:58 PM
kdrk888
Online
• • •
Upload & Sell: On
p.1 #4 · p.1 #4 · Why do most cameras only go to 30s exposure


Not sure if this helps:



Edited on Jan 04, 2018 at 02:06 PM · View previous versions



Jan 03, 2018 at 07:15 PM
dallvr
Offline
• •
Upload & Sell: Off
p.1 #5 · p.1 #5 · Why do most cameras only go to 30s exposure


Right on the money!!!

I would think that the ability to make longer exposures than 30 seconds should be as simple as a firmware update for most modern cameras. I really hate having to have an intervalometer dangling off the camera when I am doing long exposures, and then having to bring it along everywhere "just in case". It should be built in.




Jan 03, 2018 at 07:53 PM
snapsy
Online
• • • • •
Upload & Sell: On
p.1 #6 · p.1 #6 · Why do most cameras only go to 30s exposure


I believe most cameras limit regular exposures to 30s because the accuracy of the exposure calculation drops off significantly after tha, I think owing to the low-light limitations of the light meter (or image sensor for MILCs).


Jan 03, 2018 at 07:56 PM
Adam Schallau
Offline
• •
Upload & Sell: Off
p.1 #7 · p.1 #7 · Why do most cameras only go to 30s exposure


johnahill wrote:
I know medium format and a few others have this but with my time with Canon, Fuji and Sony cams none have the facility to go past 30s.


The Fuji X-T2 and X-Pro2 can go up to 15 minutes.



Jan 03, 2018 at 09:14 PM
DavidBM
Offline
• • • •
Upload & Sell: On
p.1 #8 · p.1 #8 · Why do most cameras only go to 30s exposure


johnahill wrote:
I was out using my A7r the other day and was using bulb for long exposure images.
It's not the most friendly mode, the light level is dropping and I have an ND filter on, so to check exposure I remove the filter, go to Aperture priority, get a reading and recalculate for the ND then set back to bulb mode.

Why cant we have cameras that have exposure timer up to say 8mins? Or even just the metering function to show long exp times?

I know medium format and a few others have this but with my time with Canon, Fuji and
...Show more

Various reasons, None of which mean an expert wouldnít be better off with being able to do longer exposures easily, but I can see why most camera donít...

(1) Noise gets worse (thatís why Sony have the stareater for better - mostly - except for Astro -worse.) and you start to get transient hot pixels. The makers would rather you only saw this, if at all, having made a very conscious decision to use bulb.

(2) A lot of users will get confused with an auto exposure that goes on for minutes. If the shutter gets triggered with the lens cap on, thereís a danger some idiot will send in the camera for repair.

(3) is a corollary one (1). Reviewers are likely to test noise at the longest available exposure. They donít want that to be too long....

(4) if LENR is enabled, a long exposure doubled become very long indeed and that makes (2) worse.

(5) LENR becomes more useless the longer the exposure, as the noise becomes more time dependent, and you get transient pixels that may not show up in both exposures.



Jan 03, 2018 at 09:24 PM
johnahill
Offline
• • • •
Upload & Sell: On
p.1 #9 · p.1 #9 · Why do most cameras only go to 30s exposure


Adam Schallau wrote:
The Fuji X-T2 and X-Pro2 can go up to 15 minutes.


Nice, didn't know that



Jan 03, 2018 at 09:56 PM
ytwong
Offline
• • •
Upload & Sell: Off
p.1 #10 · p.1 #10 · Why do most cameras only go to 30s exposure


Many film cameras has that 30s limitation, probably due to color shift and sensitivity is not so accurate at longer exposure (1 min exposure of film might not be as bright as 2x 30s exposure, but I have forgotten the term for that). I think I have read some explanations in a Nikon film camera user manual long long time ago(but that was likely talking about AUTO exposure), so maybe the limitation is "carried forward" to digital? (although exposure of sensor is always linear)

SR app can somehow be a workaround(but moving light like star trails, moving vesicles will be broken). Too bad apps are removed from A9/A7R3.



Jan 04, 2018 at 03:04 AM
 

Search in Used Dept. 

        


Parariss
Offline
• • •
Upload & Sell: On
p.1 #11 · p.1 #11 · Why do most cameras only go to 30s exposure


Lots of cool answers. I'd have just figured it was because film cameras only had so much room on the shutter speed dial.


Jan 04, 2018 at 03:54 AM
TheEmrys
Offline
• • • •
Upload & Sell: Off
p.1 #12 · p.1 #12 · Why do most cameras only go to 30s exposure


I suspect that for some manufacturers, it is a warranty issue to prevent heat buildup and stuck pixels. Fuji may be really good at heat dissipation through their bodies.


Jan 04, 2018 at 03:57 AM
realVivek
Offline
• •
Upload & Sell: Off
p.1 #13 · p.1 #13 · Why do most cameras only go to 30s exposure


Reciprocity is that term. All films came with their reciprocity factor in their data sheets.

This does not apply in case of digital sensors.

ytwong wrote:
Many film cameras has that 30s limitation, probably due to color shift and sensitivity is not so accurate at longer exposure (1 min exposure of film might not be as bright as 2x 30s exposure, but I have forgotten the term for that). I think I have read some explanations in a Nikon film camera user manual long long time ago(but that was likely talking about AUTO exposure), so maybe the limitation is "carried forward" to digital? (although exposure of sensor is always linear)



Good to know Fuji cams offer long exposures. Perhaps some of the Olympus cameras also offer this possibility?



Jan 04, 2018 at 04:17 AM
AmbientMike
Online
• • • •
Upload & Sell: Off
p.1 #14 · p.1 #14 · Why do most cameras only go to 30s exposure


I think it's because of the noise. My old m4/3 has 60 seconds. The noise seems to get worse, the longer exposure you need.


Jan 04, 2018 at 06:25 AM
josh-himes
Offline

Upload & Sell: On
p.1 #15 · p.1 #15 · Why do most cameras only go to 30s exposure


The Leica SL has timed exposures to 30 minutes (but this is the longest exposure allowed). It also has a built in interval mode that is equivalent to a full featured intervalometer. These user interface improvements make the SL a joy to work with for long exposures. The downside is forced long exposure noise reduction, but its a reasonable trade off in my opinion. If you need to shoot really long exposures that produce good results with no LENR, such as 4 hour star trails, the 1DX MKII is a much better choice.


Jan 05, 2018 at 06:23 AM
molson
Offline
• • • • • •
Upload & Sell: On
p.1 #16 · p.1 #16 · Why do most cameras only go to 30s exposure


Adam Schallau wrote:
The Fuji X-T2 and X-Pro2 can go up to 15 minutes.


As does the Fuji GFX 50S, but only in full-stop increments past 60 seconds.

My Canon 5DsR has adjustable exposure times out to 99 hours 59 minutes 59 seconds (or until the battery dies - whichever comes first). No cable releases or intervalometers or Playstation apps or any other extra gadgets required.



Jan 05, 2018 at 02:57 PM
johnahill
Offline
• • • •
Upload & Sell: On
p.1 #17 · p.1 #17 · Why do most cameras only go to 30s exposure


molson wrote:
My Canon 5DsR has adjustable exposure times out to 99 hours 59 minutes 59 seconds (or until the battery dies - whichever comes first). No cable releases or intervalometers or Playstation apps or any other extra gadgets required.


This is still in bulb mode though? Bulb timer?

Does the meter show anything longer than 30s?




Jan 05, 2018 at 03:43 PM
Charlie N
Offline
• • •
Upload & Sell: On
p.1 #18 · p.1 #18 · Why do most cameras only go to 30s exposure


if you have a capable camera, smooth reflections is your answer.

it's better than bulb, except for maybe some very rare scenarios.

you can see exposure beforehand as well, no calculation needed.



Jan 05, 2018 at 03:50 PM
molson
Offline
• • • • • •
Upload & Sell: On
p.1 #19 · p.1 #19 · Why do most cameras only go to 30s exposure


johnahill wrote:
This is still in bulb mode though? Bulb timer?

Does the meter show anything longer than 30s?



The 5DsR (and the 5Ds and 5D IV) have a bulb timer mode where you can set the desired exposure duration. Exposures beyond 30 seconds are not metered but I typically use this mode with my Lee Big Stopper and Little Stopper filters; I take an exposure reading without the filter, refer to the handy exposure card that comes with the filter, switch to bulb timer, and set the desired time based on the filter factor. It's so simple, even I can do it.

The other nice thing is that if you want to use LENR, it runs in the background on the 5DsR - no need to wait before starting the next exposure.

I should also mention that Canon lets you shoot in full 14-bit RAW mode - no need to switch to heavily compressed semi-JPEG format for long exposures like Sony forces you to do.



Jan 05, 2018 at 04:38 PM
doc4x5
Offline

Upload & Sell: Off
p.1 #20 · p.1 #20 · Why do most cameras only go to 30s exposure


I agree that this is a frustrating problem. I'm a former Fuji user who used the long exposure settings on the X T-2. I just returned from a visit to the Oregon Coast with my new A7RIII. It performed well but I did miss the opportunity to use exposures longer than 30 seconds. I assume one calculates super long exposures, e.g. minutes, by doing the math from a reading that the camera can actually do, e.g. if it says 30 seconds at f/5.6, it would be 60 seconds at f/8 and 120 seconds at f/11. Is there a better way? Happily digital sensors do not have reciprocity failure like Tri-X. Is there another way to calculate exposures. I'm getting an intervalometer to enable the camera to do the long exposures. Thanks.


Jan 06, 2018 at 04:26 PM
1
       2       end






FM Forums | Sony Forum | Join Upload & Sell

1
       2       end
    
 

You are not logged in. Login or Register

Username     Reset password