T90 / 300TL fault?

Last night I tried using my new (to me) 300TL with my T90; I was

trying to take a picture of a mural with the flash in FEL mode. I

followed the manual on how to set things up (T90 in Av mode, flash set

to 'mode' and 'FEL' pushed in, flash zoom-head set correctly) but

whenever i tried to take a reading, although the pre-flash would fire,

the T90 would give a reading as if there were no flash on the camera.

 

i.e:

 

without the 300TL attached, i was getting a spot reading of 1/60 @

f1.8 (50mm lens)

 

with the flash attached and set as above, using FEL mode, the reading

was exactly the same. I couldn't select any faster shutter speed as if

I did, the displayed aperture would start blinking (indicating a lack

of light).

 

- the subject was only a couple of meters away.

- the pre-flash and full flash seemed to fire OK

 

would this indicate a fault with the camera or the flash? i've only

taken a couple of full-auto pictures with the flash before, and they

came out OK. i'm not even fully sure if i may be doing something wrong

myself, although I'm sure I'm not - i tried several times with

different settings (Av, Tv, FEL, TTL) and they all acted as though the

flash gave no extra benefit at all, judging by the meter readings.

 

has anyone got any suggestions? i bought the two items from different

places, and although the T90 is under guarentee, the 300TL isn't - but

at the moment i'm not sure if the fault lies with the flash, the

camera, or me!

Perhaps I can alleviate your concerns, although I don't have an ultimately conclusive explanation to offer: I tried my T90/300TL combination as you described and got a similar result. I believe we can say that this is how the camera/flash combination is supposed to function, since it would be rather improbable that we'd both have a camera and flash that are misbehaving in the same way. I can't explain why FEL works in this way except to speculate that this is a fill-flash mode of this system, so the camera/flash combination is trying to preserve as much of the natural lighting as possible; perhaps someone else out there can provide a conclusive explanation...?

This is normal 300TL behavior. A-TTL and FEL are automatic fill flash modes. The camera will meter for an ambient light reading as if the flash is not there, exposing correctly by natural light, then automatically adjusting flash fill to balance.

 

Only in Program or TTL Auto modes will the flash serve as your primary illumination. TTL Auto is NOT the same as A-TTL...an unfortunate similarity of terms.

 

The 300TL Reference Guide will help. You may find it on Christian Rollinger's FD site. I also once posted a summary of the flash's operation on the Yahoo CanonFD group--I suppose it's still there.

 

Happy shooting.

thanks for the answers - having looked at the reference manual (specifically the bit where it says "in FEL mode the meter reading will NOT change") i think i understand how it works a little better. the instruction booklet I have is much less clear on the distinction between the modes - I was under the impression that FEL was simply a spot mode for flash, which obviously is not accurate.

 

i presume that, given that i was trying to photograph a subject which filled the frame, FEL mode was not the best mode to use (as there was effectively no background).

Mark, I lied. That summary I posted is on the files page of the CanonT90users group at Yahoo.

 

Yes, for an uncomplicated shot that needs flash as primary illumination, Program mode is the way to get automatic flash. FEL is intended for really difficult exposure situations, such as an outdoor upper-body portrait against buildings at night, where your subject occupies only part of the scene. You can spot meter the flash exposure on your subject so that the great dark outdoors won't fool the flash into gross overexposure. You can then use the highlight/shadow buttons to raise or lower the ambient light background exposure in relation to it. There's just such an example in the T90 Performance Book, which I think is online at canonfd.com.

alan - i found your file on the T90 group, which has confirmed what i'm just beginning to realize (namely that i need to spend a lot more time using the 300tl before i'll start understanding it!). i think that will help a lot, thanks