Question about Canon Rebel XT / EOS 350D Digital Camera

1 Answer

Extremely long time writing to CF card

I shoot mostly at night.  Long exposures, star trails, etc.   When I shoot anything longer than half a second, the camera takes just as long as the exposure took to show up on my preview screen.  
Ex. I shoot a 5 minute exposure at f/4.5.  From the moment the shutter closes, it takes 5 minutes to write.  Same goes if the exposure is 5 seconds or 5 hours.  It always takes the same amount of time.
I know this isn't supposed to happen because other when I've shot with other canon digital rebels, they do not have this problem.  It isn't the speed of the card, either.

Posted by on

  • clsrebel Mar 16, 2008

    I have a DS6041 33mm EOS with 1 Gig flash card that does this I think; I thought it was the shutter closing that took so long. I'm tring to shoot with out flash in special effects productions and it seems next to impossible to obtain a steady sharp image. I'm wondering if the long shutter time or writting time is part of the same problem? Desprate to shoot.



1 Answer

  • Level 1:

    An expert who has achieved level 1.


    An expert that has over 10 points.


    An expert whose answer got voted for 2 times.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 7 Answers

IIRC these cameras support a noise reduction feature through a custom function. The camera will take a second exposure with the shutter closed (i.e. against something pure black) to see which pixels in the camera are "hot", and then will use that information to remove that hot pixel noise from the original image. "hot" pixels depend on temperature and exposure length so the camera would need to do this on every shot.

Posted on Mar 18, 2008


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Image processing delay

This may linked directly to an issue with the memory card or internal storage circuits.

When the shutter release is operated, the image projected on the sensor is collected and sent to the internal high speed memory of the camera called the buffer. This buffer is very fast - but not very large in capacity. Depending on your exposure settings (NEF, JPEG, NEF w/ Preview, Large, Med Small, Fine, etc.) you may be able to take anywhere between 6 and 75 exposures in rapid succession - this means 3 or 4 per second. Once the camera's internal buffer is full, it must be sent to the comparatively slow CF card. When this happens, no more shooting can take place.

A minute strikes me as being too long for this to take. I would recommend that you remove the CF card and copy the contents to a computer. Format the card by the computer to make sure that it has the capacity indicated on the label. If it is slightly less, it is OK - if it is more than that, it may indicate a problem area on the card that the camera is repeatedly attempting store data upon. If the CF card checks out OK, return it to the camera and format it in the camera. This is a very important step. Whenever you transfer pictures from the card - whether it is with a card reader or via a cable between the computer and the camera - format the card after the transfer in the camera - before taking more photos.

CF cards have dropped in price, and you may benefit from buying a new one for use in the camera. Select a faster class card whenever possible. Memory cards do have a finite number of read / write operations and you may be reaching the end of life on yours.

I hope this helps and good luck!

Jan 16, 2013 | Nikon D100 Digital Camera

1 Answer

I am shooting with a Nioon D200 and I have to shoot at 100 iso and 1.8 in the shade in the daytime.If I go over 200 all I have it dark pics no matter my f-stop.Is this a camera malfunction.( my friend...

If you're shooting: ISO 100, f1.4 @ 1/1000 second, it is the same as:
ISO 200, f1.4 @ 1/2000 second, or
ISO 400, f1.4 @ 1/4000 second, etc.. Because each time you double the ISO value, you need 1/2 the light for a proper exposure. The ISO is the camera sensor (or film) "sensitivity to light". The higher the ISO, the more sensitive it is. That's why in the examples above, the shutter is opened 1/2 as long (or it is twice as fast - whichever you like to look at it). But it doesn't stop there..

That same ISO 100, f1.4 @ 1/1000 second picture is also the same as:
ISO 100, f2.0 @ 1/2000 second, or
ISO 100, f2.8 @ 1/1000 second, or
ISO 100, f4.0 @ 1/500 second, etc.. This is because each FULL f-stop (1.4, 2.0, 2.8, 4.0, 5.6, 8.0, 11, 16, 22 and 32) each allow TWICE as much light than the previous (higher f-stop number). f1.4 allows 2x more light than 2.0, which allows 2x more than 2.8 which allows 2x more than 4.0, and so on. So, if you get twice the light from one aperture than the previous full f-stop, and the ISO is the same, then the length of time the shutter is open must be reduced by 1/2. Hence, 1/500 is half as long as 1/1000, which is half as long as /12000, etc.

It can be represented like the exposure triangle below:
All this shows is that all three variables control the exposure. If your main objective is to change the Depth of Field (DoF), adjust Aperture and one or more of the others to get a properly exposed picture. Likewise, if you want to suggest or stop motion, you'd adjust shutter speed first - faster to stop the motion or slower to suggest motion by creating blur. ISO introduces grain to the image. The lower the the ISO value, the finer the grain is (may not even be perceptible). The smoothest color gradients come from the lowest ISO values - but they need to most light. A tripod may be needed unless shooting in direct sunlight or other brightly lit subject. ISO is a lifesaver for poorly lit subjects, night time photography, or other indoor shooting without a tripod or speedlight. The ability to shoot good looking pictures at ISO 3200 means that you need only 1/32 of the light needed when shooting at ISO 100. That means that under the right circumstances, you could hand hold the camera at ISO 3200 when the same picture taken at ISO 100 would take 32x longer. Of course, grain comes into the mix here. It may be too grainy for your likes. Experiment to how high you can set your ISO with acceptable results.

Below is a chart of the full shutter speeds, stops and ISO values. Many cameras break these down further into 1/3 steps for even more minute control. Basically, if you change the value of either shutter speed, f-stop or ISO values 1, 2, 3, 6, 9 - or however many steps - you need to adjust one or both of the others an equivalent amount to compensate to get a properly exposed picture.


Lastly, make sure you haven't set exposure compensation to a negative value. Press and hold the the "+/-" button (has a green dot) on the top panel next to the shutter release button. Spin the rear thumb dial so that it is niether plus or minus. Minus makes the picture dark (underexposed) and Plus makes it brighter (overexposed).

I hope this was helpful and good luck! Please rate my reply - thanks!

Oct 12, 2011 | Nikon D200 Body Only Digital Camera

1 Answer

I have a canon eos 550d and i have been taking photos for the past 4 months or so and not a problem till date. but recently when a take a long exposure say 30 seconds or even 10, 15 seconds, after the...

Long exposures increase the amount of noise recorded in any digital image. Your camera uses blank frame subtractive noise reduction, like most others. After a long exposure with the shutter open, it temporarily records another similarly long exposure with the shutter closed. It then subtracts any hot pixels (noise) showing in the second image from the one you have just captured as they will overwhelmingly be in the same sensor locations on both images, regardless of any image data.

While all that is going on, your camera will be busy and unavailable for use, and that's exactly what it's trying to tell you.

If you don't want noise reduction then go into the camera menu and turn it off, but you will likely find that you spend far longer cleaning up your images afterwards.

Hope this has explained the issue clearly and that you are able to take a moment to rate my answer.

Jul 28, 2011 | Canon EOS Digital Rebel XS / 1000D IS...

1 Answer

If it is a grey day out should i really use N mode? If i use B mode how long should i hold it down for?

You should only use B mode if it is pretty much dark out.Operating the shutter manually is nearly impossible to determine the time you need.When I was on a carrier,I took pictures when plane were taking off at night.You could seen the jet blast,the lights,and an outline of the plane.As well as I tried,the lights still came out somewhat wobbly.You really need a tripod for B exposures.For example,if there were a way to hold the button down,on a tripod,during the entire night,you could see the star trails due to Earth's rotation.Those are a couple of examples for the best way to use B mode.Any exposure about 1 second or less is very difficult to do manually,so yes,use N mode.Greg

Oct 28, 2010 | Holga 120N Film Camera

1 Answer

I have a Nikon D90 camera with a 180 - 300 lens that I use to shoot photos of my boys playing football. I have always had crystal clear shots from the stadium. Now that my boys are playing Varsity at...

Obviously, shooting the pics at night requires a longer exposure. If you haven't changed any settings from your daylight pics, then your camera is probably setting a slower shutter speed to compensate for less light in the stadium. You need to raise the ISO setting. You could get a faster lens, experiment with both aperture priority and shutter proiority, etc. But try the ISO first...that may do the trick.

Sep 18, 2010 | Nikon D90 Digital Camera with 18-105mm...

1 Answer

Flash Setting Causes Delay

Without seeing the image, it's difficult to pinpoint the problem. But, going on the description you've described here, my guess would be that your shutter speed is too low to record any movement sharply, or is recording movement you are making while holding the camera. Some things that you may want to review with the camera to ensure that you're shooting the images correctly:

First, if you can look at the image using a photo editing program, see if you can review the EXIF (also called metadata) file and look at the exposure. Generally, anything under 1/30th of a second will show motion blur introduced from hand-holding the camera. If the shutter speed is below this, you should consider using a higher ISO setting or opening the apperture (this equates to a lower "F" number, so "F4" allows in LESS light than "F2.8") to allow more light into the lens. Remember that doubling the ISO will allow you to make an exposure with HALF the light. The down side to this is that higher ISO settings, particularly in Point and Shoot cameras, introduce higher levels of noise.

Ensure that you are no more than 10 feet from your subject. Most on-camera flash units are much less effective beyond this distance.

If you are photographing sports/action, remember that a shutter speed of 1/250th of a second will eliminate most motion blur.

Also remember that most point and shoot digital cameras are "one chip" cameras and often have multiple tasks to perform while making an image (focus, exposure, flash, recording and writing the file are all performed at the same time...), so it's not uncommon to see delays (also called "shutter lag") in point and shoot cameras (DSLR's have multiple chips, and don't have this issue...). One way to resolve this is to depress the shutter release half way. This keeps the chip "hot" and ready to expose. Doing this with a point and shoot camera greatly increases the responsiveness to the shutter release.

Hope this helps and happy shooting!

Jul 14, 2009 | Sony Cyber-shot DSC-H9 Digital Camera

1 Answer

When on sports setting, my camera shoots slow and blurry when indoors

More than likely, your exposure- specifically your shutter speed settings- are too low. When you have fast action, you must have a higher shutter speed (Higher, meaning that the DURATION of the exposure is less. So, an exposure of 1/250th of a second is more desirable than an exposure of 1/30th of a second when shooting indoor sports. (This difference equates to about 400% more exposure, duration-wise). When shooting sports indoors, a "Fast" lens, meaning that the front of the lens is bigger, which allows more light into the camera at one time. (This normally equates to "F-Stop" settings. So, a 50mm F1.4 lens will be a "faster" lens than a 50mm F2 lens. The lower the F number, the "faster" the lens. This also equates to higher prices...) Another consideration for shooting stop-action sports photography indoors is using higher ISO settings. When you double the ISO number, you cut the amount of light required to make a good exposure in half. So, ISO 200 requires half the light of ISO100, and 400 requires half the light of 200 and so on. Typically, I use a setting of ISO 800 or higher for indoor sports (Which, BTW is my speciality...). The trade-off for using higher ISO settings is that it introduces more noise into the image, which many people find less desirable. I also wrote a few articles for POPULAR PHOTOGRAPHY & IMAGING about shooting sports. The "football" article will more than likely be the most help to you. Basically, ALL sports photography is shot the same way, and if you use these techniques, your work will greatly improve. Here is a link to those, and hope they help!

Jul 10, 2009 | Nikon D60 Digital Camera

1 Answer

Once a picture has been taken you can't take another immediately - camera says busy and the shutter fires as much as five or ten seconds later!

I suspect that you're using a file format that takes longer to write, such as a TIFF or other format that's adding compression to the image. ENsure that the file format is RAW or standard JPEG, which write fairly quickly. The other issue could be the buffer size on the camera. The buffer is built-in memory that allows the camera to store images while still shooting. The images are then taken from the buffer and writes them to the card. SLR cameras, for example, tend to have large buffers and can shoot more images without writing to the card. Shooting ONE image and having to wait for the "busy" indicator to turn off seems a bit extreme, so it this isn't an old camera or a very "cheap" camera (sub $100), than you may have an issue with the buffer memory and will want to go to a camera repair shot and have them test. Check the file format first though- I suspect that you are using a format that's more write-heavy in comparison to standard RAW and JPEG files.

Another thing that you also need to consider when using Point and Shoot cameras is that they tend to be "one chip wonders". This means that instead of having multi-chip cameras (Such as digital SLR's) that can do multiple tasks at one time (shoot, write, flash, focus, exposure...) there's only ONE chip that does all of this. If you depress the shutter release half way, it keeps the chip "hot" for shooting a photo and your performance will improve slightly.

Jul 10, 2009 | Casio Exilim EX-Z750 Digital Camera

2 Answers

Exposure number in Canon does not change

Due to the age of the camera, the Ultra 2 CF card may be using a different architecture than your other CF cards. In other words, the card is incompatible with the camera.

One other problem may be that the camera is not designed to recognize a card which is of a larger capacity.

As I cannot find the 300D on Canon's site it is difficult to find exact specifications as to the abilities of the camera, as to what type of CF card it will accept, what the largest capacity it will accept, etc.

A more fixable problem would be either that the card is not formatted properly - which may be possible through the camera itself. Please try to navigate the camera's menu to find a format option. If not, you can insert it into a CF card reader and attempt formatting it that way. Please see Here for formatting through a camera.

Also, try Here for yet another possible explanation of your problem, as #6.

If the camera is meant to take the capacity and type of CF card, and is not damaged, the only other explanation is that it is write-protected. As I do not know the exact features of your CF card, I cannot say whether or not it has a manual write-protection switch. If it does, it would be a small sliding piece of plastic or metal on the side of the card which toggles the write-protection feature. It may also be write-protected as a file system, in which case you will need to format it.

If the card refuses to format due to a write-protection, you will need to remove the write-protection from the card first and then format it.

The following picture shows a CF card with a write-protection switch on the left hand side.


If this proved helpful, please rate. If you need further assistance, please come back and I will attempt to provide further help.

Thank you and take care,
- Dshack.

Dec 16, 2008 | Canon Digital Rebel / EOS-300D Digital...

1 Answer

Long exposures

the only way i can think of is by using a remote release which should give you the option to set it for longer.

Apr 04, 2008 | Olympus EVOLT E-500 Black Digital Camera...

Not finding what you are looking for?
Canon Rebel XT / EOS 350D Digital Camera Logo

Related Topics:

66 people viewed this question

Ask a Question

Usually answered in minutes!

Top Canon Cameras Experts


Level 2 Expert

176 Answers

old marine
old marine

Level 3 Expert

2178 Answers

Donald DCruz
Donald DCruz

Level 3 Expert

17130 Answers

Are you a Canon Camera Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides