Canon T2i/550d write speed n Burst mode

[vikram1988]

Hi all,

I use a San disk Extreme SDHC card which writes at 45 mbps as my primary memory card. I have a 32 gb Sandisk class 4 ( dont know about write speed but i assume around 10 mbps ?) as my backup card. When i use the class 4 card , burst mode(RAW only) is virtually unusable. Its really slow and clicks and lags every 2 secs. and the time between shots is a lot. So planning to upgrade my backup memory card.

<question>
Whats the write speed of t2i (550d) in the continuous burst mode and whats the speed of memory card i should be buying ? Even with the 45mbps card , the camera takes time to buffer even when shooting continous Jpeg(only) after about 15-20 shots. Is this normal ? What memory card i should be buying so that the continous burst mode (RAW only or Jpeg only) performance is at its best ?

Since the bottleneck is in the camera's performance only , i'm trying to understand if a 30 mbps Sandisk Ultra card would suffice my needs or should i invest in another 45mbps extreme card.

P.S i dont care about videos

 

[vikram1988]

BUMP ...

Anyone can throw some light on this ? or any idea how i can find out more ?

 

[jeff92k7]

First of all, your Sandisk card isn't writing anywhere near 45MBps. That rating is for read speed under certain circumstances. Write speed will be closer to 12MBps.

The different classes of cards will indicate the approximate write speed. Class 4 will write at approximately 4MBps. Class 6 at 6MBps. Class 10 at 10MBps.

Read and write speeds also vary dramatically by card manufacturer. I.e. I have the same Sandisk card that you mentioned and get about 12MBps write/42MBps read speeds. I also have a Sony that runs at 8MBps write/92MBps read. Every card is different. I have found that my Sandisk card performs the best in camera. If you want to be happy, get another Sandisk card like you already have.

The burst speed has less to do with the card as it does the internal camera memory buffer. Think of the buffer like a bathtub and the data from the sensor coming in like water from a fire hose. It's going to fill up pretty fast. The output to your card is like the bathtub drain. It will never drain anywhere near as fast as the bathtub fills up. A faster card may give a slightly bigger drain size, but it's marginal at best and will never make a noticeable difference in burst performance.

Stick with name brand class 10 cards and get rid of the class 4. That's about as good as you'll get.

 

[annoyingzhang]

I had the same camera for 3 years and shot sports at my high school. I assume you are shooting sports or wildlife. If you need burst performance, the 550D is not the right camera.

I used Sandisk Extreme SD cards, same as yours. If memory is correct then I think burst in RAW I had 4-6 shots of burst before buffering (depending on ISO) and 15-20 shots in JPEG sounds about right. If you look through your viewfinder it says how many shots left until buffering - it looks like [xx] with "xx" as an integer indicating how many shots left until buffering and it's to the right of the exposure meter.

Two things that help with burst that's software related: turn off ISO reduction, it takes more time to clean the image and turn off lens correction too.

Hope this helps.

 

[Universeal]

I had a class 4 on that camera and i could do only 4 raw burst. I bought A-Data MyFlash SDHC 32GB Class 10 and i could do 7-6 bursts raw which is max. Now i have Lexar Professional SDXC 400X - 64GB but didn't try it but it should also be 7 raw bursts because is faster than previous.

 

[vikram1988]

Thanks a lot for your replies guys. Sorry, was caught up in some work and could not thank you guys last week

 

[vikram1988]

and I'm seriously considering changing the body itself. Burst mode is really important to me when i shoot birds , so might go with 7d. I dont think there'll be an improvement in IQ from 550d to 7d but the burst speed should justify a change. I'll wait for it to come to less than 1k $'s

 

[CharlieB]

I use a 7D with a 300/4 non-IS (original design). Use it with the original 1.4x converter too.

Couple of things I really like there - speed, focus options, and AFMA. My 300 needed some correction that Canon said it could no longer perform, but the body does it just fine.

I think you can find 7D's on the cheep right now... just over $1100 if you look around.

And....always get the fastest card you can afford. It makes more sense in the long run.

 

[vikram1988]

Do you guys think 7d price will come down ... ? coz of 70d announcements n all . .

 

[skfla]

Dude, I think you've decided about your class 4 card but jic: Either use it for storage only or just send it to a museum. If you try to give it to a homeless person, he'll take 1 look at it and give it back.

Reference the 7D: I love mine. Even though its mainly a back up w/ the type of shooting I do (landscape, portraits). But for anything involving action, I immediately reach for it. & yes, the price will come down. If you have time, keep looking at the Canon refurb site. They're an ok price to start with but they go on sale regularly. 15-20% off is fairly common & a couple times a year they have 30% off sales. Plus, w/ the 70D out they'll probably drop their prices again in the near future. Also call Canon for the CLP price jic the 7D is on the list (should be given the amount of them I'm seeing for sale around).

Good luck w/ your birding & take care!

 

[vikram1988]

ROFL - i'm sending it to the museum

Thanks skfia for the suggestions