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10-10-2016, 06:31 AM   #1
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Macro focusing help

I ran into a problem today. I captured an inch worm and decided to take a picture of it with my 50-200mm kit lens with a raynox DCR 250 reverse mounted on the end of it via electric tape. actually what i used for my newest bee pictures with good results. However it always seemed as though my focus was off center like i would center and focus the head but it would usually if not alway focus on the body. wonder if anyone would have any input on this thanks

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10-10-2016, 06:49 AM   #2
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Depth of field is very shallow in macro work. If the subject and lens are at an angle that accentuates the problem. With the bee shots were they sideways to the camera or otherwise flat to the plane of focus? Did you use a more wide open f stop on this shot?
10-10-2016, 07:09 AM   #3
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What's odd is the lower right corner of the photo appears to be in focus. Could it be the Raynox is not centered well? Or perhaps the camera moved between the instant you felt it was in focus and when you pressed the shutter? Or the subject moved?

Try taking some practice shots with a similar sized and shaped static object and surface using a tripod and see what results you get.

As mentioned the DOF in macro photography is very narrow. It is also difficult to get critical focus using manual focusing. Using a closeup lens the loss of light is not as severe as using extension tubes. The darkening of the viewfinder with tubes (or bellows) makes focusing all the more difficult.

A viewfinder magnifier or using focus peaking in LiveView might help.
10-10-2016, 07:13 AM   #4
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QuoteOriginally posted by inzova Quote
. . . reverse mounted on the end of it via electric tape.
Possibly not optically centered and perpendicular to the lens axis causing a tilt/shift effect.

10-10-2016, 07:14 AM   #5
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QuoteOriginally posted by UncleVanya Quote
Depth of field is very shallow in macro work. If the subject and lens are at an angle that accentuates the problem. With the bee shots were they sideways to the camera or otherwise flat to the plane of focus? Did you use a more wide open f stop on this shot?
Yes i used a f20 on this shot and i think i was using f14 to f16 on my bee shots.
10-10-2016, 07:15 AM   #6
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Hello,

It maybe that you're suffering from slightly front or back focus, and/or that the miniscule depth of field meaning errors easily creeping in.

I'm curious though, what benefit do you obtain reverse mounting a DCR250 on 50-200?

Thanks,
10-10-2016, 07:20 AM   #7
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QuoteOriginally posted by pacerr Quote
Possibly not optically centered and perpendicular to the lens axis causing a tilt/shift effect.
I was thinking that too on top of possible camera shake i'm going to mess with it on a tripod.
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10-10-2016, 07:31 AM   #8
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QuoteOriginally posted by Nass Quote
Hello,

It maybe that you're suffering from slightly front or back focus, and/or that the miniscule depth of field meaning errors easily creeping in.

I'm curious though, what benefit do you obtain reverse mounting a DCR250 on 50-200?

Thanks,
What does the front or back focusing mean? and as far as benefits go I achieve greater magnification which is basically it. For example this image isn't cropped. I wouldnt have been able to take it with the lens mounted normally on my 50 mm and i cant mount it normally on my 50-200 because the adapter doesn't fit the 49 mm thread on that lens. however You just gave me the idea of does raynox make a lens adapter for smaller lens threads? would make mounting it easier than electric tap haha. I'm aware of the 43 mm thread on the raynox which i guess would leave about 6mm if not less of play room for an adapter.

---------- Post added 10-10-16 at 07:41 AM ----------

QuoteOriginally posted by pacerr Quote
Possibly not optically centered and perpendicular to the lens axis causing a tilt/shift effect.
i didn't check to see if it was perpendicular ill check that.

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10-10-2016, 08:01 AM - 1 Like   #9
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Sensei 49-43mm Step-Down Ring SDR-4943 B&H Photo Video

---------- Post added 10-10-16 at 11:01 AM ----------

Or add a 52mm step up ring and use the clip on adapter.
10-10-2016, 10:26 AM   #10
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the depth of field is very tiny, so any slight movement with throw it off. I use it with 55-300 lens. I have used it with a tripod and without. It just takes a slight bump to move the focal point. Sometimes I do notice if I rotate the raynox a bit, but I don't notice any difference between shooting at f 5.6 and f20, both have tiny tiny dof to me. I hold my breath a lot when I use it.
10-10-2016, 11:19 AM   #11
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QuoteOriginally posted by Murfy Quote
the depth of field is very tiny, so any slight movement with throw it off. I use it with 55-300 lens. I have used it with a tripod and without. It just takes a slight bump to move the focal point. Sometimes I do notice if I rotate the raynox a bit, but I don't notice any difference between shooting at f 5.6 and f20, both have tiny tiny dof to me. I hold my breath a lot when I use it.
I try to hold my breath and brace my core as well. And i noticed that the higher f stop doesn't seem to really increase my dof either unless its such a small increase its not noticable idk.
10-10-2016, 09:24 PM   #12
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I do a lot of reverse-lens macro work, and I feel your pain. Here are some tips that I've found work:
- Use a tripod, and take multiple shots. Use the self-timer or a shutter release.
- Sometimes the magnification is so great that you can nail the focus in the OVF, but a slight nudge can move your apparatus, so be extra careful with touching it. This holds especially if your tripod is on a slipperly floor
- For living subjects like the inchworm, use off camera flash with a narrow aperture. Then you can still get a sharp result even if the subject moves.

For example, your picture was taken at 1/80th of a second, which can still cause blur if the worm moves at exactly the right time. Even a small burst of direct flash will be sufficient, and then you get the equivalent of around 1/10000s shutter speed. Though, how you got that exif data is quite surprising to me since you used f/20 - did you bump up the exposure in post?
10-11-2016, 08:49 AM   #13
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QuoteOriginally posted by automorphism Quote
I do a lot of reverse-lens macro work, and I feel your pain. Here are some tips that I've found work:
- Use a tripod, and take multiple shots. Use the self-timer or a shutter release.
- Sometimes the magnification is so great that you can nail the focus in the OVF, but a slight nudge can move your apparatus, so be extra careful with touching it. This holds especially if your tripod is on a slipperly floor
- For living subjects like the inchworm, use off camera flash with a narrow aperture. Then you can still get a sharp result even if the subject moves.

For example, your picture was taken at 1/80th of a second, which can still cause blur if the worm moves at exactly the right time. Even a small burst of direct flash will be sufficient, and then you get the equivalent of around 1/10000s shutter speed. Though, how you got that exif data is quite surprising to me since you used f/20 - did you bump up the exposure in post?
not by much to be honest i did blast it with my on camera flash though. "still waiting for my flash to come in the mail" here what I tool with the 50 mm kit lens reverse mounted yesterday.
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10-11-2016, 08:31 PM   #14
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QuoteOriginally posted by inzova Quote
not by much to be honest i did blast it with my on camera flash though. "still waiting for my flash to come in the mail" here what I tool with the 50 mm kit lens reverse mounted yesterday.
This looks pretty good. Sometimes it's really just a matter of trying a few times!
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