Need Macro Expert's help please

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I had to take some photos for work today and I don't do a lot of macro, in fact I don't do any macro. The problem I've got is the lack of DOF. I had to take some shot of damaged control boards for a report and here's one of the shots.

2366576781_64708c7d7f_o.jpg


I used the 18-70 kit lens at 70mm with 3 close up filters (+1,+2 & +4) so that I could fill the frame as I didn't want to highlight the detail through cropping if I could help it. This shot is ISO100, 1/125 and F36! Despite having such a small aperture the DOF is terrible. The focus should be on the corroded pins not the writing but I believe my camera has a back focus issue anyway and that won't affect the DOF.

How can I get enough DOF to get all the pins on focus in this instance? I did try the close up filters on my 100-300mm but that was nigh on impossible to focus with and I'm unsure whether the extra focusing distance to give DOF would be negated by the extra zoom necessary to fill the frame in the same way.

Heeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeelp!

Cheers all,
Kev
 
You could try 'focus stacking', i.e. combining several shots, each with different parts of the chip in focus in order to extend the depth of focus. There is a free downloadable tool which does this called CombineZM.
Click here for a tutorial. :)

Although I personally think the photo you have here is probably good enough for a report! ;)
 
Cheers for the compliment and the suggestion Dave. I hadn't thought of focus stacking, I'm not sure my eyesight is anywhere near good enough for manual focusing. I was kind of hoping for any answer that would help me spend less time in Lightroom too;)
 
Kev,

My simple answer would be to move 3x farther away and then zoom back in PP....your camera and lens should have more than enough resolution to do that.

Bob
 
Chage the plane of focus around. Actually take the shot head on towards the pins if possible therefore having all in focus .... If possible that is
 
What Dave said ^^^^

There's no way to get all that line of pins in focus at the angle you've taken the shot, however small the aperture you use.

Shoot the line of pins at 90degs to the axis of the lens and you should get them all in focus. That's assuming of course that it's possible to get that angle on the shot.
 
I thought about the idea of shooting the pins parallel to the plane of the sensor, but I thought the text on the chips might end up too out of focus, and it's probably important for the image/report as well.

Besides a diagonal composition will look better.

I think Bob has a great suggestion worth trying. Step back and crop the image. Simple but effective.
 
This type of shot would be perfect for a TS-E lens...probably the 90mm with a tube behind it. Is it a one off shot or a regular thing you need to do?

Bob
 
Personally I'd have thought the shot was more than adequate to show the problem. Most of those pins would digitally sharpen very well in processing.
 
Cheers for the help everyone. I have got a shot of the pins parallel(ish) to the camera but it's hard to tell if the DOF is falling off towards the edge of the frame or if it's the back focus cuasing the problem, most likely a combination of both.

2366641137_7ddc4294b4.jpg


I might end up doing more of this for work, it's hard to say as I've only been here three weeks now.

What's a TS-E lens? I'm considering switching mounts anyway so don't really want to buy any more glass until I've made the switch.
 
What's a TS-E lens? I'm considering switching mounts anyway so don't really want to buy any more glass until I've made the switch.

Its a tilt and shift lens. It allows you to adjust the angle of the front of the lens relative to the sensor. This has the effect of you being able to control the angle of the plane of focus. :)
 
What's a TS-E lens? I'm considering switching mounts anyway so don't really want to buy any more glass until I've made the switch.

Kev,

Basically it's a lens where the focal plane (amongst other things) can be adjusted. This link will provide the info in more detail http://hame.ca/tiltshift.htm

I have 3 Canon TS-E lenses...24, 45 and 90mm...they're good for architecture and product shots....but have a multitude of other uses.

Bob
 
I'd never heard of tilt and shift until the other day while browsing Ken Rockwell's site.

He gives a great example Here.

Roll your mouse over the jams to see the effect.
 
Cheers for the help everyone. I have got a shot of the pins parallel(ish) to the camera but it's hard to tell if the DOF is falling off towards the edge of the frame or if it's the back focus cuasing the problem, most likely a combination of both.

What isn't often appreciated Kev, is that it's quite common for definition to fall off towards the edges of the frame with conventional lenses. Stopping the lens down (smaller aperture) concentrates the image through the centre of the lens and usually improves matters somewhat.

Macro lenses, apart from their obvious advantages in getting close, are also ground and polished to much finer tolerances for their specific purpose, so give a much sharper image right out to the edges of the frame. It's for this reason that macro lenses are used for photographing old documents, engravings etc, where a high quality image right across the frame is important, as well as in many medical and scientific applications.
 
Cheers CT. The close up lenses have come in handy but are no substitute for a proper macro lens. I think I'll definately invest in one when I've sorted a new camera out.
 
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