OM1 focus problem - need some advanced help

Hi all,

I have a custom setting for birds in flight against the sky which is set to all focus points, CAF, bird detect and +1.7 exposure compensation. Sometimes, particularly when using a teleconverter, it simply won't find the focus and will sort of 'pulse' looking for it, without success - I think the +1.7 means there's not always enough contrast for a quick accurate focus.

In these situations I'd love to be able to quickly engage and diseangage PreMF to get the camera in the right ball park. Does anyone know if this can be done through button assignation or any other way? Or does anyone have any other tips to overcome these annoying situations? For info, I often shoot small passerines at quite a distance, to help me identify them, not for great photographs!

Many thanks,
Sean

Which lens? Does it have a focus limiter switch? If so set it to one that excludes the closer distances assuming the bird is further away. Vise versa if close. If the lens used does not have a focus limiter switch you may be able to do this through the menus but I have not looked into that. Also, you could use manual focus +autofocus to try and get close to the initial focus point.

Andrew

You can use the focus limiter in the AF menus. Just set the far limit to, say, 200m and it should never switch to the sky - if that is the cause of your problem. It could sort of work like PreMF.

I am not sure how this works with bird recognition which searches the whole of the AF area for a bird shape. You could try using a smaller AF pattern so that it has less sky to search to find a bird shape.

Are you trying to photograph single or multiple birds and at what range? If the target is too small in the viewfinder there may not be enough pixels on the bird for bird recognition to work.