fixed ISO with digital camera - DPChallenge Forums

Sony 16-50mm f/3.5-5.6 E-mount

12/26/2006 10:46:10 PM · #1

...is stupid.
and it took them YEARS to realize that.

jmsetzler

Sony Alpha a6000

12/26/2006 10:49:31 PM · #2

Nikon AF Nikkor 50mm f/1.8D

12/26/2006 10:51:18 PM · #3

like, ISO 500, ISO 600, ISO 700...or ISO 150, ISO 180.... u know
sure took them long enough to realize that with digital, there shouldn't be a fixed value with large gaps in between.

David.C

12/26/2006 10:57:35 PM · #4

Haven't some digital cameras had 1/3 stop increments in ISO for several years now? For that matter, wasn't it possible to get film in 1/2 stop ISO increments?

When I read your first post I thought you were refering to the newer sensors that have different sized photo sites to capture highlights and shadows seperately. The difference is size translates to a difference in sensitivity (or ISO).

David

Nikon AF Nikkor 50mm f/1.8D

12/26/2006 11:02:22 PM · #5

Originally posted by David.C:

newer sensors that have different sized photo sites to capture highlights and shadows seperately. The difference is size translates to a difference in sensitivity (or ISO).

hey, interesting. care to elaborate? thanks

David.C

12/26/2006 11:10:28 PM · #6

Originally posted by crayon:

Originally posted by David.C:
newer sensors that have different sized photo sites to capture highlights and shadows seperately. The difference is size translates to a difference in sensitivity (or ISO).

hey, interesting. care to elaborate? thanks

Fuji's Super CCD SR that comes in their pro line of SLR's, the FinePix S3 and up coming S5. Here is there website with more information.

David

Bear_Music

Sony 24-70mm F4 Vario-Tessar T* FE OSS

12/26/2006 11:12:34 PM · #7

You know how we currently have two "modes" we can use? Tv and Av, aperture/shutter priority. I've always thought it would be cool to have a third mode where you lock in both the desired shutter speed and aperture and the camera sets the correct exposure by changing the ISO :-)

R.

Message edited by author 2006-12-26 23:12:53.

12/27/2006 12:23:25 AM · #8

Originally posted by Bear_Music:

I believe the Pentax K10D have that function, Robert. But I could be wrong.

12/27/2006 11:59:55 PM · #9

Originally posted by crayon:

like, ISO 500, ISO 600, ISO 700...or ISO 150, ISO 180.... u know
sure took them long enough to realize that with digital, there shouldn't be a fixed value with large gaps in between.

As far as that goes, why should there be discrete values in aperture priority or shutter priority mode? That is, why should the shutter speed values be limited to 1/2 or 1/3 stops when in aperture priority instead of a continuous value? (and the converse)?

12/28/2006 12:05:31 AM · #10

Originally posted by hankk:

not an expert, but shutter speed and aperture values are rather mechanical in nature, I think. So it may not be that straight-forward. But ISO values? Come on, it's the digital age! ;)

I think the biggest problem with digital cameras is that they try too hard to mimick film cameras.

12/28/2006 12:14:54 AM · #11

Originally posted by Bear_Music:

And a new program mode where you can select ranges for parameters, and which one gets changed first, like:

speed: 1/250 to 1/500 prefer 1/250
Aperture: f/2.8 to f/16 prefer f/4
ISO: 100 to 800 prefer 100

Priority: Speed, ISO, Aperture
out of range priority: ISO, Aperture, speed (used when you can't get good exposure within the stated limits, sort of a safety shift).

12/28/2006 12:26:58 AM · #12

Originally posted by crayon:

Originally posted by hankk:
As far as that goes, why should there be discrete values in aperture priority or shutter priority mode? That is, why should the shutter speed values be limited to 1/2 or 1/3 stops when in aperture priority instead of a continuous value? (and the converse)?

not an expert, but shutter speed and aperture values are rather mechanical in nature, I think. So it may not be that straight-forward. But ISO values? Come on, it's the digital age! ;)

I think the biggest problem with digital cameras is that they try too hard to mimick film cameras.

OK, aperture may be a lens function, but shutter speed is part of the body, so the next gen of camera could do this.

I agree that ISO could be adjusted continuously, but this would be tough given the nature of the user interface (I don't want to scroll too much to change ISO). But if an auto-ISO system were added, the ISO could be in very small steps (like 100, 101, 102....)

Note that I can set my camera to use 1/2 or 1/3 stops for aperture and shutter speed. So one lens gives apertures of 4, 4.5, 5.6, 6.7, and 8 in 1/2 stop mode and apertures of 4, 4.5, 5, 5.6, 6.3 7.1 and 8 in 1/3 stop mode. In shutter priority mode, in 1/3 stop mode, seems that I can't get f/6.7 So it seems that the aperture is fixed, but may have more steps than the current programs use.

Message edited by author 2006-12-28 00:30:21.

12/28/2006 12:31:19 AM · #13

Originally posted by hankk:

OK, aperture may be a lens function, but shutter speed is part of the body, so the next gen of camera could do this.

Yup, and maybe someday, electronic shutter would be good enough to be considered into the design too. This takes into consideration that sensor and system bus designs have improved along as well.

12/28/2006 12:34:13 AM · #14

actually this "shutter speed" thing should take advantage of the whole digital technology - like allowing a camera RAW file to contain the same photo with different shutter speeds. Hmm, how should I explain this? You know, it's down at the photosites, where the RAW records the different amount of lights at each photosite at different micro-seconds. This would give the photographer a whole new dimension in post-processiing.

I still think that digital-camera designs should break out completely from the old film-camera designs. Remove all the barriers that is limiting the digital camera from it's full potential and possibilities.

Message edited by author 2006-12-28 00:37:05.

Canon EF 24-105mm f/4.0L IS

12/28/2006 12:03:34 PM · #15

Another issue is "why does the mirror have to move three times in AEB"? Why not just let the shutter open 3 times? And why limit AEB to 3 exposures? I'd like 5 or 7 or even 9 spaced 2 EV apart for HDR.

Don't know about recording the sensor at different times--reading the photosite may destroy the info it contains, or at least affect the info in it. And does it take longer than 1/8000 to read all the photosites? If it does, there may be a great difference between the first site read and the last site read if you have a very fast shutter speed.

An LCD shutter may be whats needed--no moving parts, very fast response, etc.

robs

Canon EOS R6 Mk II

12/28/2006 12:14:10 PM · #16

Didn't one of the earlier Canon digitals have no shutter (or it had one for bulb or something)?? If you think about it - they should just be able to cut the signal on/off and have the sensor exposed all the time. Would make for super super fast fps - catch is writing to the card.

I agree that expansion in ISO would be great. I know Nikon has something and someone mentioned ones that the Canons do it in one of the auto modes (never checked as I never use those picture things).

David.C

Nikon AF Nikkor 50mm f/1.8D

12/28/2006 02:32:52 PM · #17

Originally posted by crayon:

How would this differ from a digital video recorder? Just layer the frames as blend as desired.

David

12/28/2006 09:29:03 PM · #18

Originally posted by David.C:

Originally posted by crayon:
actually this "shutter speed" thing should take advantage of the whole digital technology - like allowing a camera RAW file to contain the same photo with different shutter speeds. Hmm, how should I explain this? You know, it's down at the photosites, where the RAW records the different amount of lights at each photosite at different micro-seconds. This would give the photographer a whole new dimension in post-processiing.

I still think that digital-camera designs should break out completely from the old film-camera designs. Remove all the barriers that is limiting the digital camera from it's full potential and possibilities.

How would this differ from a digital video recorder? Just layer the frames as blend as desired.

It's different because you take ONE photo, but this photo's RAW file contains information of light at different milisecond differences. I believe this will be possible when they design a fast enough bus and a suitable sensor.