Lens advice - Not sure what I want

swag72

swag72

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Sara
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I have my 100-400L for wildlife shots. I have been using it extensively over the last week and have decided that there is one problem with it - Focussing distance.

The minimum focussing distance is 1.8m. I found myself in many ocassions where I could get much closer to the critter, but the lens just wouldn't let me.

I do like to have nice big bugs etc, so still want something with a good length, but a shorter minimimun distance. Does that make sense and do they make it?!!:)
 
Sounds like you need a macro lens there

One of the longer ones such as the 150mm or 180mm offerings with a teleconvertor will do nicely.
 
Uneducated_Rick said:
It should focus with extension tubes :thinking:

It only reduces minimum and maximum focus distance - it shouldn't affect auto focus
Click to expand...

How about the light loss you get with extension tubes, that will surely affect the autofocus?
 
I was using F8, but in good light. I used all the extension tubes, so would I have been better only using 1 or 2? I was surprised at the fact that it wouldn't focus though.

Will have to look into that focussing lark with the tubes. I couldn't work out why they wouldn't focus when I tried them - There's no trick to it is there?
 
Doesn't matter what aperture you were using, the lens was still at its maximum when you were autofocusing, and the extension tubes don't alter the aperture since they are just hollow tubes, they just increase the distance from the focus plane to your sensor. It should autofocus!
What sort of critters are you after? I think a dedicated long macro would be the best. As for birds, I think 1.8m would be more than enough to fill the frame with even the smallest bird at 400mm on a crop camera!
 
I was chasing butterflies mostly. The larger ones are OK, but the smaller ones, I would like them to fill up more of the pic without having to crop.

I tried my 100mm macro, but that didn't do the job.

I reckon my 100-400 with a focussing distance of a couple of feet would do it nicely:D
 
:p well I think that in that case the extension tubes will be your best bet. Find the combo that works for you, even though I would strongly suggest to consider the 180mm macro. I think it would be really ideal for that kind of photography. That's why it's made actually! (y). But it's an expensive beast. Second alternative (and in my to-buy list) is the Sigma 150mm macro. Again an amazing lens! Add a 1.4x TC, and you'll get a 210mm f/4 macro lens, giving you enough distance to take photos of those critters without scaring them!
 
Perhaps you should try a close up lens. I have one for my 100-400 L for just this purpose (though I've never actually used it for real!). It's just such a simple solution and AF works fine. Hoya +1 77mm, £49. It changes the focusing range from a max of 4ft or so, down to a min of about 22in from the front element.

http://www.warehouseexpress.com/product/default.aspx?sku=11983

While it cannot do image quality any good, it doesn't seem to do it major damage. And the benefits of being able to go that much closer are well worth it.

Extension tubes do lose you light and if your 50D thinks it's got less than f/5.6 it will shut down the AF. I'm not sure what those Kenkos are telling the camera but there's a bit of AF headroom up to about f/6.3 which should be okay with a short tube (which is all you need). You might need to tape the pins if you go the Extension tubes method, so the camera doesn't worry its pretty little head unnecessarily.
 
If you already have access to automatic tubes, you are probably best sticking with them and I would suspect that a single 12mm or 20mm will be all that you require to get the working distance you need.

You have to remember though that whilst the extension tube will reduce minimum focussing distance (which is why you are using it in the first place) it will also reduce the maximum focussing distance available too, so it is unlikely that you will be able to focus to infinity whilst the tube is attached (although some longer lens's focussing range can go past infinity, and if you are lucky with the smallest tube on you may still get infinity focus, whilst gaining at the short end).
 
I use Canon's 500D diopters on my 300/4 and 400/5.6 for this type of situation. Brings in the working distance quite well and handy to have in the bag for occasions when working close with long MFD lenses.

There are details here about its usage on the 100-400.

Bob
 
Sara, the Canon 500D is just an expensive +2 dioptre close up lens under another name. It costs £130. I don't believe it is optically any better than a Hoya equivalent, but Bob might be able to correct me on that. The Hoyas are single coated.

With a +1 dioptre you get as close as you can to a seamless reduction in minimum focusing distances, with the normal lens, and with the +1 attached. There is a gap, but you should be able to work around it. With the 500D or any other +2 lens, the gap you have to work around becomes quite large even though you can get closer. And the stronger the close up lens, the more it it impacts on optical quality.

On the other hand, if you can pursuade your short extension tube to AF, since you already have it, that might be the best way forward.
 
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