Canon 100-400 Ghosting problems

[Alfred Forns]

Hi Steve

Would suggest to test you lens Its easy. Set up a target like a newspaper and check results. Would try wide open and stopping down always with enough shutter speed. btw test both close up and far away ... there could be a variation.

Mine is very sharp and have no problem acquiring focus for bif. Have been nailing purple martins !!! btw the lens will even produce sharp results with converters contrary to popular belief.

When the lens first came out, years ago, there were some that were soft. Current crop seems fine.

[Steve Large]

Hi Alfred and Rocky,
Thanks for the quick reply. Just got back from a trip with the lens this past weekend. I was at a look out point on one of the local islands and photographed Turkey Vultures and got the same result.

Rocky, the shutter speed was 1/2000 at F/8, still that tell tale ghosting around the wing and face. I really don't think that it is a focusing problem as much as a stability problem. Some have commented that using a UV filter can cause something like this but I have not done any testing with my UV filter off (your thoughts?).

Alfred, I know what you mean about being a good BIF lens. That is why I really would like to persue a fix for this problem. It is much easier in the Spring and Summer to use a lens such as this because most of my subjects are relatively close. I am also considering getting a bush hawk to save my shoulder because now I spend quite a bit of time lugging a Wimberly and tripod around for the 500 F/4.

Steve

[Daniel Cadieux]

Some have commented that using a UV filter can cause something like this but I have not done any testing with my UV filter off (your thoughts?).

I was going to suggest that too, especially if it's an el-cheapo filter. Doesn't cost you anything to try some tests without it!;) I use the 100-400 on a 40D with more than satisfactory results, and I used it on a Rebel XT for 3 years before that with the same great results.

[Steve Large]

Hi Daniel,
Yes indeed. I have noticed your results with your 100-400. I will try a more extensive test without the filter on. If this doesn't produce good results I will ship it off to Canon for the once over. Before I might have blamed myself for the soft images but now I know that it is too regular a problem to be user error.

Thanks for your input,

Steve