Jump to content

Shutter In Digital Camera


Recommended Posts

Does anyone know a digital camera which does not have any mechanical shutter? Maybe Sip could answer here, I still could not figure why a mechanical shutter is needed in a digital camera when electronically there must be a way to shut the sensor? I need a camera which does not have any shuter which is a source of vibration.
Link to comment
Share on other sites

Does anyone know a digital camera which does not have any mechanical shutter? Maybe Sip could answer here, I still could not figure why a mechanical shutter is needed in a digital camera when electronically there must be a way to shut the sensor? I need a camera which does not have any shuter which is a source of vibration.

So that you have control over the timing of the image taking. No difference wether you touch sensor or shutter.:)

Link to comment
Share on other sites

So that you have control over the timing of the image taking. No difference wether you touch sensor or shutter.:)

 

I know that the shutter is supposed to do this. I understand its necessity on mechanical camera's. But since digital camera's are electronic, why should this not be handled electronically, by a time interval, the sensor takes the information for a time interval then ignore(switch off)) what comes next. I don't see the logical reason why there should be a mechanical shutter before the sensor which is electronical, why not just switching it of?

Edited by QueBeceR
Link to comment
Share on other sites

I know that the shutter is supposed to do this. I understand its necessity on mechanical camera's. But since digital camera's are electronic, why should this not be handled electronically, by a time interval, the sensor takes the information for a time interval then ignore(switch off)) what comes next. I don't see the logical reason why there should be a mechanical shutter before the sensor which is electronical, why not just switching it of?

You need to tell the camera to store the image because everytime you move the sensor gets new image in.

Link to comment
Share on other sites

You need to tell the camera to store the image because everytime you move the sensor gets new image in.

 

Yes, but not if you switch the sensor off. All I am saying is that since the sensor is powered, why can't we just switch it off.

 

Like this.

 

1/80: .....off, off, off, off, off, off, on, on, off, of, of, of, of...

1/160: .....off, off, off, off, off, off, off, on, off, off, off, off, off,...

 

I don't understand why we need a shutter when we can simply switch the sensor on for the exposure and the rest of the time the sensor might only be on the off.

Link to comment
Share on other sites

Yes, but not if you switch the sensor off. All I am saying is that since the sensor is powered, why can't we just switch it off.

 

Like this.

 

1/80: .....off, off, off, off, off, off, on, on, off, of, of, of, of...

1/160: .....off, off, off, off, off, off, off, on, off, off, off, off, off,...

 

I don't understand why we need a shutter when we can simply switch the sensor on for the exposure and the rest of the time the sensor might only be on the off.

How do you plan to tell the camera what image to take and when to take I mean timing wise.

Link to comment
Share on other sites

How do you plan to tell the camera what image to take and when to take I mean timing wise.

 

The same way as a mechanical shutter, it closes open and close, the same way as we could switch off, then on and then off. I fail to see the problem, unless having the CCD exposed to light without a protection is bad.

Link to comment
Share on other sites

Quebecker .. I don't really know how a CCD sensor works but I suspect there might be some setup time required for the sensor to charge up ... if you leave it open, it will just accumulate charge so it may be why you need a mechanical shutter there.

 

For CMOS sensors, I think you can get away with no shutter because you can do it electronically as you said. A lot of still cameras use CCDs but you see CMOS becoming more and more used (especially lower end).

 

You might have better luck with a high end video camera ... they usually use electronic shutters to take pictures from what I understand. But their resolution may not be enough for what you need.

 

Is the mechanical vibration from the shutter really that bad? I mean does it actually make the sensor move by more than a pixel? :eek:

Link to comment
Share on other sites

Quebecker .. I don't really know how a CCD sensor works but I suspect there might be some setup time required for the sensor to charge up ... if you leave it open, it will just accumulate charge so it may be why you need a mechanical shutter there.

 

For CMOS sensors, I think you can get away with no shutter because you can do it electronically as you said. A lot of still cameras use CCDs but you see CMOS becoming more and more used (especially lower end).

 

You might have better luck with a high end video camera ... they usually use electronic shutters to take pictures from what I understand. But their resolution may not be enough for what you need.

 

Is the mechanical vibration from the shutter really that bad? I mean does it actually make the sensor move by more than a pixel? :eek:

 

The thing is that there are other lens involved(the camera is on another optical unite), so this shutters little vibration is actually making a differences because it creats aberations which looks like chromatical, it isen't a disaster, but I would like it if there was no such vibration. I have tried two camera's, and the error is minimised by giving more exposure time, but sometimes I need it for moving specimens.Maybe I am pushing precision a little bit on the extrem.

Link to comment
Share on other sites

Obviously you are using some sort of tri-pod, and an electronic shutter release (like a remote, or a timer) and not your clumsy thumb, right? ;)

 

It's mounted on a 'scope and very well mounted, with screws, it is really the shutter Vava, since long exposures minimise it, and the problem accentuate when there is vibration on the table.

 

Maybe I'll do what Sip suggested, some cheap camera which don't use any shutters. Sip, does all CMOS cameras have no shutter? There is no question that I will spend near a thousand box for a video camera which will be secrewed permanently and which I won't use for anything else.

Link to comment
Share on other sites

BTW, it can't be my fingers, I use a canon because you can control it from the computer through the USB. So I don't touch it.

 

1 - If it's on the same table as your computer/mouse etc. the vibrations could transfer.

2 - Are you using a "zoomed" lens? As the focal length of the lens gets longer, the minimal vibrations will have a greater effect.

3 - Also, depending on how everything is mounted together, the additional weight of the camera on the armature of the scope could accentuate any vibration effect.

Link to comment
Share on other sites

1 - If it's on the same table as your computer/mouse etc. the vibrations could transfer.

2 - Are you using a "zoomed" lens? As the focal length of the lens gets longer, the minimal vibrations will have a greater effect.

3 - Also, depending on how everything is mounted together, the additional weight of the camera on the armature of the scope could accentuate any vibration effect.

 

I know that the problem is your second point. The scope in question is a microscope, and I did everything as possible to minimise vibrations to the minimum, it is on a vibrationless environment. This aberation becomes noticeble at 400X, at 1600X, it start playing on my nerves. I know it is the shutter, because on long expositions it is minimised, and I figured out that it was perhaps because the picture is formed for a longer period of time when there is no shutter vibration to it and actually minimise the shutters 'noise.' When I remove my quickam's lens and adapt it to fit, this 'noise' totally disappears on pictures taken with the quickam(but I scrap the picture as it seems that quickams are sensible to infrared), but I pay for the quality of the picture, since this way I can't have better than 640X480. It is like the vibration is from the inside of the camera and the shutter is creating a vibration from the inside and which is amplified because of the magnification. Maybe this explains why those pro camera's to fit on a microscope seems to be like Quickams without shutters. But they cost over a thousand and are far from giving me the resolution that a digital camera in the 300$ range provide. :( The ideal would be to buy many camera's and try them, maybe all camera's with shutters don't have the same problem return those that don't satisfy me and keep the one which shows the best result.

Link to comment
Share on other sites

Quebecker ... I recently got a Canon SD700 with image stabilization ... this might be a good excuse to get one!!! I can tell you this camera is absolutely amazing. I tried and tried and it never takes a bad picture!!! You can be moving your hand violently around and take a picture of people and their faces will still be in focus! :lol: Edited by Sip
Link to comment
Share on other sites

Quebecker ... I recently got a Canon SD700 with image stabilization ... this might be a good excuse to get one!!! I can tell you this camera is absolutely amazing. I tried and tried and it never takes a bad picture!!! You can be moving your hand violently around and take a picture of people and their faces will still be in focus! :lol:

 

Whatcha do with your old SD400? :)

Link to comment
Share on other sites

It's still around ... I'll use that for offroading and when taking the boat on the lake (you might remember what happened to my old GPS) ... I'll keep the new one for night shots (image stabilization and night mode = teh WIN!). The 400 was starting to show some wear and tear but it still shoots pics like a champ ... I've taken more than 4000 pictures with it!

 

The SD700 is half the thickness with a 4x optical zoom (vs 3x), has an LCD that's almost 60% larger, battery that lasts a lot longer, and uses the tiny SD memory as opposed to the compact flash. It's a LOT faster than the old one too ... You can take a lot of pictures in continuous mode although I haven't tried to see how fast it can really go. But even with all those features, it was really the image stabilization that pushed me over the edge to upgrade. I can now just set up the camera and hand it to anyone and they'll rarely screw up the pics and make it fuzzy :D

 

This one has an underwater mode too but the underwater case is something like $130 extra. The other features I still have to read about are the ISO800 speed and the "kids and pets" mode :o

Edited by Sip
Link to comment
Share on other sites

Quebecker ... I recently got a Canon SD700 with image stabilization ... this might be a good excuse to get one!!! I can tell you this camera is absolutely amazing. I tried and tried and it never takes a bad picture!!! You can be moving your hand violently around and take a picture of people and their faces will still be in focus! :lol:

 

From the picture of the camera, it doesn't seem that it has a filter thread or something on which we can fit it on another unite.

 

Can it really do ISO800? Did you try it on that mode, I wonder how much noise it generate on ISO800.

Link to comment
Share on other sites

I haven't played with ISO 800 ... it might just be a marketting gimmick. But I'll try to play with it and le tyou know. But yah it doesn't really have any way to attach anything to it except for the regular tripod hole.
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...