Need gear for taking photos of small parts

pointnshoot · Oct 24, 2012

Hello,

I've been asking all the camera-folk I know and have done some research online, but I'm having trouble finding the answers I need on this one, so I just made an account here and am hoping someone can help.

I do a lot of photos of tiny parts using the macro mode on a point-n-shoot (Canon SD1100IS) and a little photo box I built. I'm thinking of investing in a nicer camera and am having trouble figuring out exactly what I need.

The parts range in size from a small grain of rice to a credit card, are indoors, and do not move. The 4 biggest challenges are:

1) Controlling and capturing the details surrounding the object. Normally I want the background all white or all black and sometimes like a nice shadow produced the object. A lot can be done in post processing here.

2) Capturing very reflective surfaces without washout. I don't have an example photo of this because I usually mess around with the lighting to get the problem to go away, but it is a very time consuming and frustrating process sometimes. Something like this can be quite annoying:

3) Getting good detail in parts that are all white or all black - it's so easy to washout or have things too dark. It was very hard to get everything just right to get the detail in this photo, and it is still quite grainy and not very good:

4) Getting good depth of field is very hard - this is the most important one. When shooting so close we can only get part of the item in focus, and just as annoying, I don't really have good control over what part:

Click to enlarge and you'll see how out of focus the front and back corners are:

The part of the photo that's in focus looks great to me, too bad the depth of field is only ~0.1"

I can normally fiddle around for a while and solve the the first two problems and get something that looks pretty good, but the depth of field cannot be improved with my current camera.

From reading/chatting I've decided I need a camera with a remote flash and better sensor to solve my lighting and detail problems. Manual zoom on the lense will let me choose exactly which area of the part that I want perfect focus. I also need something that still takes good photos with a small aperture, which I understand will improve my DOF.

I've been looking at DSLR's and like the Canon T3i - I like all the features and would plan to buy the 430EX flash or something similar to go with it. It isn't clear to me if a macro lense is needed and what it would do for me. Without the equipment in hand I really don't have a way of gauging what kind of DOF I would get with the standard kit lense. Would a macro filter help me?

I should note that I also plan to use my new camera for plenty of other general photo taking, so I want something all around nice in addition to performing at this specific task. I'm thinking $1,000 should be enough to do what I want and be very happy with the results. I could be convinced to spend more..maybe.

If you have any input I'd love to hear from you!

Thanks,
Christopher

tirediron · Oct 24, 2012

For help with your lighting, I would suggest "Light, Science, Magic" which will tell you more than you ever wanted to know about all aspects of photographic lighting. Equipment-wise, the body you choose doesn't matter a great deal; a T3i would do just fine. While a macro "filter" will help, the problem with them is that they generally have VERY poor rendition on the edges, so while the centre might be sharp, the periphery will be very blurry and soft.

My suggestion would be to purchase a dedicated macro lens; there are many of the available both from Canon and third-party makers. The longer the focal length, the greater your working distance from the subject (ie If a 60mm macro lens will allow you to be 3" from the subject shooting 1:1, then a 105mm might allow you to be 6" away), but the prices increases with every mm of length.

Shallow DoF is a physics issue, and there's not much you can do about it, withough software. Focus stacking is a technique whereby you take several shots of the product change your point of focus slightly with each one until you have a series of images which span the whole subject in sharp focus, and then, blending them with software (I like ZMCombine - freeware) to produce one image which is fully in focus. LOTS of tutorials on how to do this on-line.

pointnshoot · Oct 25, 2012

After further reading it seems that something like the Canon SX40 might do very well for me. My hangup is that I have no way of calculating the DOF I would get and the quality of the photo. Can anyone comment?

KenC · Oct 25, 2012

Some of the issues you raise won't go away no matter what equipment you have. Lighting is tricky, especially for small and/or shiny objects. To improve that you need more knowledge about lighting and then possibly better lighting equipment. A better camera will not help here. Depth of field is also difficult at this distance. If anything, the small-sensor point and shoot cameras give you more DOF than a DSLR. Focus stacking, as mentioned, is a possibility. I've never explored it myself but have seen some nice results. There are plenty of DOF calculators online and I'm sure you can find one for the type of sensor you end up using. At least the graininess you mention would be much reduced with a DSLR, but I think lighting appears to be a bigger issue.

Dao · Oct 25, 2012

Take a look at this

The_Traveler · Oct 25, 2012

dofmaster.com for calculating DOF

Overread · Oct 25, 2012

As has been said the issue here is going to greatly come down to the lighting - the light science and magic book should help you a lot there and I'd second getting a copy of it and reading it cover to cover a few times. Getting the lighting right and getting a working setup and understanding of the lighting will make the job a lot lot easier for this kind of photography where the lighting really is the key element.

After that the depth of field and quality. You might actually want to stick with your current camera, the point and shoots have smaller sensors which mean that you get a greater depth of field over your subject. Now if you upgrade - say to a DSLR - you'll get a much bigger sensor, so even though its higher quality, you'll have a much thinner depth of field.
Now you can counter this with the focus stacking software approach (as mentioned above) which can give you some great results, and is something you should look into, esp if you're already hitting the depth of field limits with your current setup.

One thing you might want to consider is that a DSLR can let you use a tilt-shift lens. These let you shift the plane of focus to where you want it. If you think of the plane of focus like a sheet of paper over the subject parallel the front of the lens. Where the thickness of the paper is the depth of field. Now with a tilt shift you can shift the paper so that its thickness (ie depth of field) covers the exact subject area you want it to.

One downside is that there are no macro tilt shift lenses, further you might have some difficulties dealing with the rice grain sized subjects (which for a DSLR will already require a more specialist setup to work with).

The_Traveler · Oct 25, 2012

One issue that hasn't been dealt with is how these images are to be used.
If they are meant for the web then you don't need to fill the screen to get a very good image for the web - and that would simplify your technique some because you could merely chop the center 8 or 900 pixels out of the frame.

This is the full frame of a shot with a 60 mm macro on a dslr on a hassock in my office. No artificial lighting (small grains of rice)

then I can chop the image I would need for a web photo right out of the center.

Of course you would want a better background and more controllable lighting

pointnshoot · Oct 25, 2012

The photo stacking is cool but I hope to get a workable solution with less post-processing

dofmaster should help me - I'm playing around with it now. Do I need to tell it something about the sensor size somewhere? One thing I noticed: I'd previously assumed that moving away from the object and zooming in would improve DOF, but it seems to make not difference. Just moving further away does improve DOF, and as The_Traveler pointed out, I can just crop out what I need. The only problem with this option is focusing - with the object taking up such a small part of the frame, you either need to tell the autofocus to use a very specific spot, or be able to manual focus, ideally with a 'zoomed in' preview. I know the Canon T3i has the latter feature.

The photos are mostly for web but I do like to have largish versions available (maybe 1200 pixels wide for a quarter-size part, perhaps smaller for smaller items).

I am also very attracted to the idea of taking photos of bugs and such. I like do these with my point and shoot but some that I've seen done with better lenses that are quite mind-blowing. People are doing some pretty awesome things with a Canon SX40 and a Raynox DCR-250 filter, which is a pretty cheap setup.

I should also reiterate that I would like a camera that I can use for other fun projects as well. HD video, low-light performance, decent flash, are all things my current point and shoot is lacking.

The_Traveler · Oct 25, 2012

Use this link and you can pick out your camera model, etc.
Virtually all dslrs have focus points you can put on the item.
A smaller slightly older dslr and a macro lens is capable of anything you need.

Find a budget, look for a decent used body and lens and you're set.
Then it's just learning the camera and developing a setup that will work.

pointnshoot · Oct 26, 2012

Lew,

Thanks, a calculator like this is exactly what I need to get moving. I can put in the specs of my current camera and compare the calculator's output to that of prospective cameras. One thing I'm not finding is the frame width: for a given subject distance, focal length, and aperture, how wide (in inches/feet) is the frame? This will tell me how much of the image I'll be cropping out for a given subject and if I'll have enough pixels left to make me happy. Will the sensor size affect the frame size, or are all of these calculations independent of sensor size? Another thing the calculator isn't going to tell me is minimum focus distance, so I have to find that for each lens and take it into consideration.

Do you have any comment on bridge cameras like the Canon SX40 I mentioned? For this camera best DOF is achieved with 24mm zoom and f/8, and I can get as close as I want. I guess most dslr's with the standard kit lens would give me 18mm and f/22 which is a huge improvement in DOF, but I'd have to be at least 1.5ft away, and I think the subject would take up a tiny portion of the frame at 18mm.

Are there any cameras that will do simple photo stacking onboard? Even if it just did 2 or 3 layers that would be a great improvement. In my head I imagine picking out 3 points of focus on the display then telling it to shoot and stack. Such a feature would be worth a hundred bucks, at least.

Overread · Oct 26, 2012

One thing that the DOF calculator doesn't take into account though is the effect of diffraction. With any camera (although generally more noticeable with DSLRs and larger sensors) as you reduce the aperture (ie use larger f numbers) the nature of the sharpness of the photo changes. Generally most get sharper from wide open (smallest f number) up to around f8/10 (it varies depending on the camera and the lens); thereafter that point the sharpness will drop as diffraction kicks in. Most generally remain very usable up to around f13/16 and after that point the softening becomes more pronounced (although if you are just displaying photos online you can go further without must trouble, since reducing the size of a photo and sharpening both before and after resizing will "hide" the softness).

As for focus stacking I'm aware that Helicon Focus has some automated focusing properties that allow it to control the camera (when tethered) to do a series of focus stacked shots automatically. I've never used this software before though so I've no idea which brands (I assume canon and nikon are supported) it works with nor how to use that feature specifically.
This method shifts the focus by adjusting the focus on the lens itself (ie using the AF motors to control it).

The only other automated setup I'm aware of is the Stack Shot automated focusing rail. This method instead of controlling the AF motors, instead controls the distance between subject and the lens, moving the rail and triggering the camera for each staged shot.
StackShot - Focus Stacking Macro Rail

That said looking at the subjects I've a feeling that you could very easily do these manually without too much fuss. A good stable tripod and tripod head would be needed for any photos; I strongly recommend a Manfrotto Junior Geared head for a tripod head - legs you can be a bit more free to choose though a 055XPROB or 190 series legs from Manfrotto would be good starting points. The geared head is a simple 3 way head design, but with a fine control knob for each axis. It's slower to use, but for macro its ideal as it lets you adjust the frame very carefully in each axis and without any droop after you've set the positions.

Manual focus stacking can be easily done with a focusing rail. You just set the focus to the closest point you want infocus and take a shot, then adjust the rail to move the camera a little closer (thus moving the focus) and take another shot. Repeat over and over to get a series of stackable shots. Note that automated methods can make this faster and sometimes a bit easier, however they each come with their own price (I would look more into Helicon focus for indoor work as you can easily tether to a computer - it also has the cheaper price and the software itself will also do the stacking for you so its a good package to get).

Note software side there is no market leader for focus stacking software. There are many options from free to paid, but each one works a little differently, but no single one works best. Note that sometimes one software option can fail whilst another will work on a specific series of photos, the properties for this are however too complex to repeat shot to shot so you can't tailor your shooting to one specific package (it makes owning more than one software options more viable for stacking, however with simple subjects and with easy control you shouldn't have many problems getting stacks to work since you shouldn't be missing frames or having many problems during shooting).

The_Traveler · Oct 26, 2012

This link will allow you to calculate the height and width of the field for any given focal length and lens to object distance.
You can do a bunch of calculations and then build your own reference table for setups.

A wide angle lens will give you the best DOF and any given lens-subject distance but at costs of distortion and smaller subject size.
I know nothing about that camera.

If I were doing this and wanted good results and flexibiity, I would get a used body (like a D90), a macro lens, tripod and a kit zoom lens. Then you can use the body and kit lens for fun and go to the macro for actual work. You may never need stacking.