12-01-2018 10:46 AM
Firsty going to have to apologise as although I've had m camera for 1.5 years I'm a little wet behind the ears with it.
I have an EOS70D with a Canon Zoom Lens EF 70-300mm 1:4-5.6 L USM lens, and I never take the hood (mentioning incase its relevant).
I use the camera to take pics at the local running races which I've been doing since I've had the camera but recently the camera seems to be jamming up, not sure if its struggling with focus, but it starts off good then half way through the pack of runners its stops for a rest before letting me take another single snap or two then needs a rest??
I haven't a clue what's causing this as its never happened in the past, takes great photos for the first few minutes before this starts to happen, apprecaite any ideas>???
12-01-2018 10:58 AM
Sounds like you are filling the buffer internal memory in the camera and it has to stop while it writes to the card and frees up buffer memory space.
If you arfe confident it didn't do it before under the same shooting conditions and frame rate then look for differences - new card (with slower write speed?)? - has card been formated in camera recently (if not, do it).
Based on what you described I don't think you have a camera problem.
12-01-2018 12:17 PM - edited 12-01-2018 12:19 PM
I think John diagnosed it correctly and it doesn't sound like a problem with the camera itself.
Are you shooting in RAW or JPG (or RAW+JPG)? JPG will allow a larger burst with most (maybe all) current cameras compared to RAW so depending upon your model if you must have a high sustained burst rate you may need to consider JPG for some of your shots. I always shoot RAW files only but saving as JPG instead of RAW is a possible solution to the issue if you are currently using RAW.
As John noted card speed has a major impact on how fast the camera can flush the buffer to the card and all cards are definitely not created equally. The results in this site are a bit dated but it does serve to illustrate the differences in card writing speed and the impact from shooting RAW vs JPG or RAW+JPG to help you decide what will work best for you.
I suspect that formatting the card in camera vs having a card that has simply had the images erased multiple times will also impact how quickly the buffer can be flushed to the card so you might try an in-camera format of your card if you have just been erasing images after shooting.
12-01-2018 12:26 PM
That sounds logical and feels like it could be something to do with that, any recommendations on the best type of card to use.
I've never formatted the card (just done) one thing i noticed when it was 'resting' was the  how many frames left was flashing.
12-01-2018 12:31 PM
Thanks for the responses, just confirmed JPG only but god knows what card I'm using.
Think this could be an issue along with never formatting it, any advice on what card to purchase to see if it improves.
12-01-2018 01:27 PM - edited 12-01-2018 01:35 PM
"I've never formatted the card (just done) one thing i noticed when it was 'resting' was the  how many frames left was flashing"
I'm pretty sure it does that when the card is being written to - camera can't tell how many shots remain because its in the process of putting images on the card.
Any SDXC card should be compatible with your camera.
12-01-2018 01:43 PM
Take a look at the site I posted earlier to see what the faster cards were and if it is still available get one of those or the current version from that manufacturer.
I strongly urge you to purchase from B&H or another camera retailer; a couple of years ago the cards I ordered from the "amazing etailing giant" were counterfeit. It was easy to return them but apparently counterfeit cards are very common so be careful where you buy. I get all of mine from B&H now.
12-14-2018 10:15 AM - edited 12-14-2018 10:19 AM
Thanks for taking the time to post your resolution. That is helpful to others who may come across this thread.