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Rock
03-11-2008, 11:31 AM
I don't know if this is the right place but anyway I got a question.

Yesterday while shooting the FF Procession, I ran into a problem with my camera. I could only get about 3 or 4 shots before I had to wait for the camera to catch up. I am wondering if the cards or the camera are what causes this.

I have a 300D, (I know, I know) and my cards are 1 gig Ultra I cards. I think they are 80x speed cards. So with the older camera, would faster cards help or is the bottleneck, the camera itself? I want to upgrade but need a few more months so I just really need a bandaid for now I guess.....

iunno
03-11-2008, 11:33 AM
are you shooting in raw or jpeg, are you doing a continuous burst?

this won't necessarily help, but here's some CF and SD bench tests (http://www.kenrockwell.com/tech/cf-sd.htm)

Rock
03-11-2008, 11:37 AM
raw. I like the control it gives me after the fact. Would I be better in jpeg with this camera?

iunno
03-11-2008, 11:38 AM
well, if you are shooting in continuous bursts, like one frame after another your camera only has a 4 JPEG buffer, that would explain it slowing down and thinking...then continuing on.

Geekybiker
03-11-2008, 11:40 AM
Thats pretty normal. The 300d has a pretty small buffer IIRC. Plus the older cameras don't have the greatest write speeds no matter the card.

Jpeg will write much much quicker. (plus you can shoot more in your buffer.)

thechickencow
03-11-2008, 11:59 AM
Geeky is right-
The biggest drawback to teh 300d is its slow write speed. Its actually slower than any cards you can get so it really doesn't make any difference (I've tried different from Ultra to Ultra III personally with no difference).

iunno
03-11-2008, 12:01 PM
Thats pretty normal. The 300d has a pretty small buffer IIRC. Plus the older cameras don't have the greatest write speeds no matter the card.

Jpeg will write much much quicker. (plus you can shoot more in your buffer.)


well, if you are shooting in continuous bursts, like one frame after another your camera only has a 4 JPEG buffer, that would explain it slowing down and thinking...then continuing on.

:unamused:

Geekybiker
03-11-2008, 12:03 PM
:unamused:


wait... 4 jpeg buffer? Dont you mean raw?

Rock
03-11-2008, 12:07 PM
I think it is 4 raw buffer. But I wasn't shooting bursts, just that the trucks were coming so close together that I was taking one shot right after the other. I will have to try the jpeg setting sometime, I just hate to lose the control I have with raw.....

thanks guys

iunno
03-11-2008, 12:10 PM
hrm...

http://www.dpreview.com/reviews/specs/Canon/canon_eos300d.asp

"4 IMAGES"

thechickencow
03-11-2008, 12:11 PM
Its just slow, really plain and simple. I found it super frustrating.

JPG is better, but you're right about losing control/quality.

iunno
03-11-2008, 12:14 PM
The EOS 300D's Continuous Shooting mode is rated by Canon at 2.5 frames per second, for a maximum of four frames. This matched very well with the results of my own performance tests. Do note though, that the number of consecutive shots could be limited by Compact Flash space, if your memory card is nearly full.

hrm, if the card is nearly full it'll be real laggy too

Geekybiker
03-11-2008, 12:37 PM
hrm...

http://www.dpreview.com/reviews/specs/Canon/canon_eos300d.asp

"4 IMAGES"



Smart buffering is something which was first seen on the EOS-D60 and was carried forward with the advent of the EOS 10D. I'm glad to report that it appears as though this method of buffering is also a feature of the EOS 300D, although the EOS 300D has a smaller buffer than the EOS 10D (4 images compared to the 10D's 9 images). The Smart buffering method improves both single shot and continuous drive shooting. The EOS 300D uses its internal buffer for two purposes: buffer the data as it comes from the image sensor (we will call this unprocessed data) and subsequently buffer converted image files before they are written to the CF card. Note that the camera will not write to the CF card unless it is "idle", this means that if you hold the shutter release button in the half-press position the camera will hold the converted image files in the internal buffer until you release.
Image processing sequence:

Record data as it comes off the image sensor, unprocessed data (approx. 9.3 MB per shot)
Store this unprocessed data in the SDRAM buffer
Take unprocessed data and convert into image files (JPEG or compressed RAW)
Buffer these converted image files (JPEG approx. 3.0 MB or RAW approx. 6.0 MB)
Write JPEG / RAW image files to CF card This means that although the buffer can be filled with a continuous burst of four shots it quickly regains buffer space as the unprocessed images are converted into the JPEG or RAW image files. In a real life situation it's easy to believe that the stage 2 runs concurrently to new unprocessed data being buffered.
Take four shots in a continuous burst, keep your finger half-pressed on the shutter release and despite the fact that nothing is being written to the CF card you will see the buffer space indicator fairly quickly count back up again. Remove your finger from the shutter release and the counter doesn't change but you can observe data being written to the CF card (indicator light on the CF compartment door flickers).
Repeating this test for both JPEG Large/Fine and RAW I discovered that the buffer has space (without writing any data to the CF card) for:

4 x JPEG Large/Fine images and approx. 2.6 seconds later indicates space to shoot 4 more
4 x RAW images and approx. 4.9 seconds later indicates space to shoot 2 more (you must then allow RAW images to be written to CF before any more space is available) The EOS 300D takes approximately 0.65 sec to convert the unprocessed data into a JPEG Large / Fine file, approximately 2.45 sec to for a compressed RAW file.

Colorblinded
03-11-2008, 12:38 PM
I think it is 4 raw buffer. But I wasn't shooting bursts, just that the trucks were coming so close together that I was taking one shot right after the other. I will have to try the jpeg setting sometime, I just hate to lose the control I have with raw.....

thanks guys
You don't need to shoot in bursts, but if you shoot fast enough that the buffer starts to get full you're going to have to wait for it to clear some room.

Rock
03-11-2008, 12:57 PM
Thanks for all the input everybody.

I guess I need to start looking toward new gear. I was afraid that was the case......

Hrm, must go look at some camera's.... Haha!

Rock
03-11-2008, 12:59 PM
Oh, and let me see if I got this right?

If it was a newer camera, with a bigger buffer than the card speed could affect it? I am trying to understand how the different cards play into this as well.

iunno
03-11-2008, 12:59 PM
you've proven yourself as a perfectly capable (and good) photog with the gear you have, only look into new gear when your current stuff limits what you can do.

iunno
03-11-2008, 01:03 PM
Oh, and let me see if I got this right?

If it was a newer camera, with a bigger buffer than the card speed could affect it? I am trying to understand how the different cards play into this as well.

yeah, different cameras have different buffers, as an example, some with unlimited jpeg at 3.5fps, some are limited to XX jpegs at 3.5fps. it varies greatly on the body, you can compare them side-by-side here (http://www.dpreview.com/reviews/sidebyside.asp) <- i use that site for ALL my spec comparisons.

as for different card speeds, check out that link i posted in my original reply, they do some great tests that really lay out speeds

Geekybiker
03-11-2008, 01:29 PM
If you like to shoot raw, and shoot quickly it may be time to look into a semi-pro body (20d, 30d, 40d etc) They typically have much better write speed and larger buffers. I think just about any camera will slow down on raw eventually. I know mine will get 10 frames RAW full speed before it starts waiting for write (and will write about 1 raw per second) even though it'll shoot jpeg until the card is full.

iunno
03-11-2008, 01:32 PM
continuous drive specs:

5d Yes, 3 fps max 60 JPEG, 17 RAW
30d Yes, 5 fps or 3 fps up to 30 JPEG images
40d Yes, 6.5 fps or 3 fps up to 75 JPEG images
XT Yes, 2.8 fps, 14 JPEG or 4 RAW frames
XTi Yes, 3.0 fps, 27 JPEG or 10 RAW frames
XSi Yes, 3.5 fps, 53 JPEG or 6 RAW frames

Geekybiker
03-11-2008, 01:40 PM
continuous drive specs:

5d Yes, 3 fps max 60 JPEG, 17 RAW
30d Yes, 5 fps or 3 fps up to 30 JPEG images
40d Yes, 6.5 fps or 3 fps up to 75 JPEG images
XT Yes, 2.8 fps, 14 JPEG or 4 RAW frames
XTi Yes, 3.0 fps, 27 JPEG or 10 RAW frames
XSi Yes, 3.5 fps, 53 JPEG or 6 RAW frames

Does not compute. Typically raw is about 1/3 of jpeg (if there is a jpeg limit)
That 6 raw has to be an error. Maybe 16? That would be about right.

iunno
03-11-2008, 01:44 PM
nope, it's not an error. that's correct, unless canon sent out incorrect specs to EVERYONE.

Geekybiker
03-11-2008, 01:57 PM
nope, it's not an error. that's correct, unless canon sent out incorrect specs to EVERYONE.

Huh. Weird.

iunno
03-11-2008, 01:59 PM
yeah dude, i searched around and everyone has the same specs, it's weird.

Colorblinded
03-11-2008, 03:19 PM
I'm guessing that is an error, it at least seems bizarre it'd drop like that over the previous gen, unless it's due to the increased resolution, etc.

Geekybiker
03-11-2008, 03:34 PM
I'm guessing that is an error, it at least seems bizarre it'd drop like that over the previous gen, unless it's due to the increased resolution, etc.

Yah, but the # of jpegs increased. A Raw is about 3x the size. So buffers hold about 1/3rd the files and take about 3x to write. A larger image should reduce both the jpeg and raw burst if nothing else changes. So we can assume it has a larger buffer and/or higher write speed.

6 raw is probably 4 buffered +2 written during the ~2 seconds it takes to capture them.

That means ~12 buffered jpeg +~6 written for ~18 jpeg based on the 3x file size.

The only way I can see it *maybe* happening is they have a good jpeg compression engine and a terrible raw compression engine.

Colorblinded
03-11-2008, 03:38 PM
I didn't look, is the XSi 14 bit? the JPEGs are still 8 bit, and perhaps that is not stated for maximum resolution in JPEG. Don't know all of it but I wouldn't be surprised if that's a typo.

thechickencow
03-11-2008, 07:02 PM
Oh, and let me see if I got this right?

If it was a newer camera, with a bigger buffer than the card speed could affect it? I am trying to understand how the different cards play into this as well.

Rock, I was feeling the same way about my 300d, and pretty much any canon body is an upgrade. I went to my 40d and its awesome. Even jumping to a 30d or something is a big step up.

Colorblinded
03-11-2008, 07:08 PM
Oh, and let me see if I got this right?

If it was a newer camera, with a bigger buffer than the card speed could affect it? I am trying to understand how the different cards play into this as well.
Even if you had another camera with a similarly sized buffer, if it could write to the card faster it would be less of an issue (within reason, depending on the file size, etc).

Buffer size & card write speed are two different things. The buffer is an internal short term memory which is high speed so that it never limits the camera in terms of write speed, only capacity. You can shoot at max fps until you fill the buffer.

As soon as you take an image I believe it's always stored in buffer and then transferred to the card. If you have a faster write speed to the card then this takes less time, so if you imagined shooting fast enough to approach filling the buffer, a faster card write speed would mean you could continue to shoot more rapidly without running in to the wall (or at least for longer before it really chokes up).

Once you fill the buffer you have to wait until space has been cleared by the camera as it copies things to the memory card. You can shoot as soon as enough room for a photo exists, but you'll be back to a full buffer pretty quickly if you don't let it all transfer to the card.

A faster card, if your camera has the card write speed to take advantage of it, is just another way to ensure your buffer empties faster and avoids hitting full.

Rock
03-11-2008, 08:04 PM
Well I was just looking and the 20D says 3.5 fps and 9 frames total and then it says 5 fps and 23 frames max. So I am thinking the 3.3 and 9 would be raw? That would be better than were I am at and they seem to be priced decent right now.

kensington
03-11-2008, 09:43 PM
Well I was just looking and the 20D says 3.5 fps and 9 frames total and then it says 5 fps and 23 frames max. So I am thinking the 3.3 and 9 would be raw? That would be better than were I am at and they seem to be priced decent right now.

sorry, re-read your post, my original onemakes no sense now

jacobsen1
03-12-2008, 10:09 AM
late to the party, I know, but yeah, you've just filled your buffer. Faster cards will help with how soon to the next shot, but only marginally.

I have this same problem with my 1D and had it with my 1DmII... :lol:
But I've never hit the buffer with the 5D. :shrug:

Yes I know it's because of what I shoot with the 2 different bodies.

Rock
03-12-2008, 07:06 PM
Well I think I am going to try and sell my current gear and fund an upgrade. I missed several good shots due to the buffer filling up to quickly. Not cool.....

thechickencow
03-13-2008, 04:18 AM
Well I think I am going to try and sell my current gear and fund an upgrade. I missed several good shots due to the buffer filling up to quickly. Not cool.....

I'll sell you my 300d so you can have a second camera firing away if you'd like!