Macro lens for 25mm subject

[madhu1]

<p>Hi Folks, I'm looking to buy the most appropriate macro lens to shoot circuit boards sized 25mm x 25mm in fine detail. Based on what I've read, seems the EF-S 60 mm macro (and perhaps an extension tube) would do the job accounting for distance-to-subject, 1:1, etc. So in terms of just the ability to shoot the subject in great detail, am wondering if the 60mm lens would be adequate for such a tiny subject or if I need to get the MP-E65. I use a 20D. Thanks, Madhu</p>

[craig_meddaugh]

<p>You don't need the MP-E65 unless you want to shoot photos of individual features on the board. Any 1 to 1 macro lens will get you what you want on a 20D, and if you need a bit of extra magnification, you can always get an extension tube. If you want to save some cash, you can use the Canon 50/2.5 with an extension tube and pocket 200 bucks in savings. </p>

[bob_sunley]

<p>A 20D has a 15x22mm sensor, so you don't need 1:1. A 1:2 will almost fill the short side of the image with a 25mm object.</p>

[Mattman944]

<p>I occasionally shoot circuit boards at work. If you are shooting a board by itself, the EF-S 60mm is a good choice. If you ever need to shoot the board wired into an assembly, the extra working distance of a 100mm might help.</p>

<p>Have you considered lighting? Flash can be problematic with shiny parts on a board. And a populated circuit board is usually electrostatic discharge sensitive, so light tents usually can't be used. Since color accuracy usually isn't a priority, I use ambient light, a sturdy tripod, and a long exposure. I might add a small goose-neck lamp to get extra light on a specific location. </p>

[tom_mann1]

<p>1. If you are worried about ESD, just run a thin wire to the board and clone it out later in PS. Don't let that concern get in the way of good photography.</p>

<p>2. In my experience, the problem with photographing circuit boards is almost always DoF, not ultimate resolution in one plane of perfect focus. Because of the vastly increased DoF you get from tiny-sensor P&S cameras compared to FX, or even DX format cameras, try shooting a board with a good quality P&S that has a macro feature. If you take care of lighting, camera stability, and all the other things you would do for a "real" shot with your "big" camera, you may be pleasantly surprised at what you can get using a good P&S at even moderate apertures. </p>

<p>3. You should also consider the benefits a short FL lens provides in terms of perspective. I rather prefer the dynamism of this look (ie, almost like a city-scape looking down from a low flying helicopter through a forest of skyscrapers) to the static, isometric-drawing-like look one gets with a longer FL lens from a plane flying at 20k feet.</p>

<p>Unfortunately, for the next several days, I'm away from home and don't have access to my image archive, otherwise I would post some examples. </p>

<p>Tom M </p>

<p> </p>

[tommyinca]

<p>Ah? For ESD protection, isn't grounding the PCB with a wire is like holding a lighting rod outside on a lighting strom. What ever electro discharge on the light tent will now aim right at the PCB. </p>

[tommyinca]

<p>60mm macro will do. IMHO, if you have the budget, get the older version 85mm tilt-shift Nikkor (non PC-E) or the EF 85mm T/S plus some extension tubes. This will yield better DOF for angled flat objects like PCB. </p>

[Mattman944]

<p>If you are following strict ESD protection rules, the board should be grounded and any ESD generating materials should be kept 1 meter away. Probably overly conservative, but those are usually the rules for expensive electronics for space.</p>

<p>Now if you just need to shoot one for advertising, use a non-functioning reject board. </p>

 

[paddler4]

<blockquote>

<p>I use ambient light, a sturdy tripod, and a long exposure. I might add a small goose-neck lamp to get extra light on a specific location.</p>

</blockquote>

<p>I do most of my flower macros with aim-able household lights (reading lights are great) and long exposures. YOu might want to add diffusers <strong>http://tinyurl.com/44obszu</strong> to lessen reflections, but be careful to keep them far enough from the bulbs. Ambient light might be better in terms of reflections.</p>

<p>And i second the recommendation for the EF-S 60mm macro. It's a fabulous lens. I use it (in preference to my EF 100mm L) for most indoor tripod work.</p>

[madhu1]

<p>Thank you all for your feedback. ESD is not an issue since I'm shooting just the circuit boards. But good to know for future. And glad to receive alternatives to consider such as using P&S macro mode, TS-E or old FL lenses (though all of which may require close-up filters, TCs, extenders, or mount converters to get the equivalent 1:1). But looks like I won't go wrong with the EF-S 60 and that's what I wanted to get confirmed. Appreciate...</p>