HELP!! High speed continuous shooting with 7D

[Rocco]

Hey guys, I'm stumped on this one.


I'm beginning to do some time lapse photography and I came across a bit of a roadblock tonight. I was setting up for a shot in the city for a shorter segment of the time lapse, street level, and I was attempting a simple, very slow pan with my tripod. For this shot the idea was to use my 7d's high frame rate to attempt a video like shot without the people or cars seeming too choppy or alien.. and I am now very confused.


First of all, I understand the basics behind the buffer, and that there are only so many shots my camera can process before the buffer is full and my camera/card has to catch up, thus interrupting the continuous shooting. So I figured I'd use a smaller image size.. i.e. mRAW or sRAW or even one of the medium or small jpegs. Now, with my camera set on sRAW I can get about 150-160 images before my card is bogged down. (I have two Hoodman RAW 675x UDMA6 8GB cards.) But even on the smallest, lowest quality jpeg setting I can get four shots before I start to see "busy" in my viewfinder. This makes absolutely no sense to me. Why is it that I get a shorter duration with jpeg??


Basically I'm looking to be able to shoot continuously without any interruption for at least 300-400 images. Is this just something that's not possible? Maybe it's a setting on my camera that I'm just overlooking? Everything is set to manual with faithful image style, iso 100. Shutter speed is in excess of 500. Do I just need to bite the bullet and go with the 4fps setting that's reminiscent of my old Rebel XT?


HELP! []


Thanks in advance,


Rocco

[TakahiroW4047]

Could it be that because the camera needs to convert the RAW images to JPEG, that

[Sean Setters]

My guess is that you accidentally had the camera on SRAW + JPEG, else you were using a high ISO (both would affect burst rate substantially). Check page 59 of the 7D manual.

[neuroanatomist]

Even large/fine jpgs should shoot over 100 frames before it slows down. But, if you

[Dr Croubie]

I've done this before too (wondered about the low number of frames before 'busy', that is).


Try looking in the menus for 'High ISO Noise reduction', 'Long exposure noise reduction', and i think maybe 'highlight tone priority' too. turn them all off.


also, only shoot RAW/mRAW/sRAW, it's the JPEGs that get all the fancy processing, make sure you're not shooting JPEG too.


If you must shoot JPEG, also look at the number in the bottom right-hand corner of the viewfinder, it should be in the hundreds, not single-digits.


.


if none of them, how fast MB/s is that CF card you're using?

[Daniel Browning]

also, only shoot RAW/mRAW/sRAW, it's the JPEGs that get all the fancy processing, make sure you're not shooting JPEG too.

Unfortunately, Canon doesn't have a way to disable JPEG processing. Even if you are in RAW mode only (no JPEG), Canon still does a full round of heavy duty JPEG processing just so it can embed a 3 MB JPEG "preview" inside the raw file. I wish they would allow me to disable it, even if it meant a very slow image review, but they don't. Back in the good old days, Canon stored the preview separately, so that it didn't needless bloat the raw files. A guy can dream...

[neuroanatomist]

Actually, Dr Croubie, JPGs are faster. The RAW to JPG conversion is not the limiting factor, the processors are fast. It

[Rocco]

I've done this before too (wondered about the low number of frames before 'busy', that is).


Try looking in the menus for 'High ISO Noise reduction', 'Long exposure noise reduction', and i think maybe 'highlight tone priority' too. turn them all off.


also, only shoot RAW/mRAW/sRAW, it's the JPEGs that get all the fancy processing, make sure you're not shooting JPEG too.


If you must shoot JPEG, also look at the number in the bottom right-hand corner of the viewfinder, it should be in the hundreds, not single-digits.


.


if none of them, how fast MB/s is that CF card you're using?

The CF Card is a<span>Hoodman RAW 675x UDMA6. Plenty fast enough. Turned out that both the High ISO Noise reduction and Long Exposure Reduction were the culprates. It still bogs down after a bit shooting sRAW, but the highest quality jpeg will shoot 1000 frames if I want it too at 8fps. Thanks for all the help guys.

[Dr Croubie]

hmmm, clarification:


When i said

[neuroanatomist]

RAW has no in-camera processing so they go faster compared to JPEGs with all the processing, even though the RAW filesizes are bigger.

Shooting RAW is like shooting RAW+JPG but only saving a small JPG instead of the full size version. As Daniel points out, even with RAW the camera is still doing the JPG conversion, and scaling that converted image down for inclusion as a preview image in the RAW file container. Thus, even if you're shooting RAW only, your burst rate is still affected by the JPG settings (e.g. high ISO NR), because the camera is doing an in-camera JPG conversion for every shot you take. So, it really all boils down to the file size being the limiting factor.


Incidentally, the JPG is what you see on the LCD during review, and more importantly (and something many people don't know), the histogram you see when you review an image on-camera is based on the JPG preview, even when shooting RAW. I see many people write that they they shoot RAW only, so things like white balance and picture style (which affects color saturation, contrast, etc.) don't affect their shots, and they just ignore those settings. But if you use the histogram to make exposure decisions, those setting can affect your RAW image (indirectly), if your exposure changes result in lost detail on either end of the dynamic range.