70D and 270ex flash

I am trying to introduce my 270ex into my photo taking experience. I mostly shoot withou a flash and in Manual or Av or Tv when called for. However, for the holidays and all the indoor activities I thought to try it out and to use if for direct flash or just bounced for effect.

When I have the flash on, I will shoot either Av or Tv and I have the external flash menu set at ETTL and have done both first curtain and High Speed Sync.
I also have my 18-135 IS STM lens on.

This is where my trouble comes in.

1. In Av mode, if I choose a wide Aperture, the shutter speed is very slow. When I take a picture, the flash is on but shutter remains open for 3" to about 1/30 (these are indoor, not so greatly lit room)
2 In Tv mode, if I choose a faster shutter such as 1/100 or more, the images just come out too dark (bounced or direct).

I am usually shooting candid subject and lets say distance can be within 10 to 20 ft

As for ISO, I try several, A, 400, 800)

What am I doing wrong? Is this flash just too weak?
I am using rechargeable batters/fully charged, but are rechargeables causing issues?

I am just looking to try and introduce the flash to be subtle and not harsh (reason for wanting to bounce it off ceilings).

Are there any known tips for this type of external flash use?


Here is one in Tv mode (1/100, F4.5, ISO 400) Metering is Evaluative.

Try manual mode while using flash. In AV mode the camera exposes as if the flash were only providing fill. Your camera does provide a custom setting that limits the shutter speed in AV mode while using flash, but m mode is just ss easy and allows you more options for balancing ambient and flash.

Thanks...do you mean M mode on Camera or Manual Flash mode (rather than first curtain or High Speed Sync)?


If M mode for camera than What mode is recommended on the flash (Manual or High Speed Sync)?

M mode on the camera. Ettl on the flash. Select a shutter speed 1/250 or below and the aperture you want for creative reasons. The flash will fill the gap between the two. Avoid using hss as it robs you of power, not that its applicable for this situation anyway.

I do most of my flash work with the following settings. Manual (camera) mode, ETTL-II flash mode, 1/250, f/8, ISO 1600, +2/3 FEC on apsc, +1/3 FEC on ff. That is a good starting point.

I use a 580EX II & 60D/6D. Your flash may be a bit underpowered for photos like the one you posted above. Increasing ISO can help. I don't recommend Tv mode for flash work. You have no control over the aperture in TV. Use Manual or Av (setting Av flash-sync speed to 1/250 will make it behave like the camera is in manual mode).

This is all excellent information thank you so much!

I'll respectfully disagree with the settings suggested above. 1/250 just leads to unnecessarily dark backgrounds. F8, only if you want f8 for depth of field. To see the difference select a subject, not a whole room, and take 2 shots one at 1/250 and one at a1/60 and compare.

What you can also do is set the shutter speed range in the flash menu. For AV you have 3 options
#1 Auto let the camera set the speed default,
#2 1/250 to 1/60
#3 1/250.
I have used the 270EX on a room that size but not with bounce, not enough power.

gonzogolf wrote in post #17351214
M mode on the camera. Ettl on the flash. Select a shutter speed 1/250 or below and the aperture you want for creative reasons. The flash will fill the gap between the two. Avoid using hss as it robs you of power, not that its applicable for this situation anyway.

I agree with you. As the OP is not up to speed with flash, my suggestions stand as a decent place to start. Figuring out how to blend flash and ambient is probably best left until after the shooter has figured out how to get a good flash exposure. Different approaches to the same destination, I suppose.

There was a thread on another forum on under-exposure with flash on the 70D. It was described as a camera flaw. Has this been fixed on later models?

Hi,

My 70d which otherwise is very good has problems with bounce flash. In my case I'm using my 430 ex II. When using TTL with a f3.5 to 5.6 lens, the bounce flash pictures are too dark without correction. If I press the fel button (*), before taking the picture exposure is calculated correctly. There are a number of posts on this issue which describe how to work around the issue.

I'd try pressing fel before taking a bounce flash picture to see if that helps. My SL1 does not have the issue and I believe it has been fixed for the 7DII.