specimen photography

I have spent many hours searching and trying to pull together information for choosing the right camera for my needs. I’m stuck on a couple of issues. I have been asked to choose a camera in the $2500 range and a lens in the $2500 lens. The purpose of this camera would be to photograph museum bird specimens. We have a Bencher copymate II stand. There doesn’t seem to be much published about this kind of photography. We’ve run some tests with a Canon EOS 5D Mark II using a 50mm lens and we are experiencing some distortion.

Does anyone have any ideas or experience in specimen photography? We will be using this camera for flat objects as well. I am not sure if a macro lens would be overkill for birds. Any ideas would be helpful. I’d also like to avoid any kind automontage if possible but I don’t know how feasible that is.

Additionally, any settings that have proven to be successful with this kind of photography would also be helpful.

Thank you,
Christina

I WOULD THINK A 100MM MACRO WOULD BE THE LENS WITH THE LEAST DISTORTION.

What kind of distortion are you getting? Can you post an example? What brand 50mm lens are you using? The 5D is a remarkable camera and you can get excellent 50mm lenses, which would be a "normal" focal length for this camera. I would not expect optical distortion.

You don't say anything about lighting. To my mind, that would be a more critical concern than the camera and lens. Are you shooting in the museum? There are members on this forum who are experts on lighting. At a minimum, I would think two softboxes the size of your subjects would be in order. These would also be helpful with the flat objects. You should also consider your backdrop.

The longer the focal length generally the less distortion you will get. I am not exactly sure what we are talking pictures of. dead animals in a museum if I understand correctly?

Essentially, this is portraiture.
A 5D will be fine; a 1Ds perfect.
Lens selection will depend mostly on the required working distance and the specimen size.
The 100L should be in your kit, and will cover everything from very detailed work to whole mount images of objects up to a metre or so given adequate space. For very large specimens (albatross with spread wings, or a standing moa), you may need something shorter. Canon offers a 50/2.5 macro that would warrant a look.

Certainly, for photography of flat objects you should select a true macro lens as field correction in these is considered a priority in design.

Do give very careful consideration to lighting - that will probably have the biggest effect of all in determining the quality of your images.

If detail is important and you can manual focus, Zeiss 50 Makro Planar and/or Zeiss 100 Makro Planor

Fidlina wrote in post #12422261
We’ve run some tests with a Canon EOS 5D Mark II using a 50mm lens and we are experiencing some distortion.

Christina, we really need to understand the "distortion" you are experiencing better. Photos with descriptions of what you are seeing would help.

I suspect the "distortion" you are seeing may not be true distortion (typically caused by lens design flaws) but something known commonly as "perspective distortion". Perspective is controlled not by a lens' focal length, but the distance between the camera and the various elements in the scene in front of the camera. My suspicion is that you are using the camera too close to the subject. If you were to pull the camera back to twice the distance from the subject and use a 100 mm lens (suggested above more than once), you will find that the perspective distortion (typically seen at the corners of an image) will be significantly reduced.

You can run a quick no-cost test to prove the point. Pull the camera back to twice the distance that you've been using it at. Then, crop the image to 1/2 the length and 1/2 the width of the resulting image. The resulting cropped image would have the perspective and framing that you would achieve with the 100 mm lens. The background blur (if any) might be a little bit different than if you used a 100 mm lens, but you could at least see if the additional camera-subject distance reduces the perspective distortion that I suspect is what you've been experiencing.

For more information on perspective and how to control it, please read our "sticky" (now found in the General Photography Talk forum) tutorial titled Perspective Control in Images - Focal Length or Distance?.

How large are the specimens and are you shooting close-up details of them or the entire subject, or both? Will all the shots be taken on the copy stand or would some be done at a greater distance? How are the resulting images being used?

What I'm getting at is how much magnification you need. For purposes of macro photography, magnification is expressed in relation to the size of the image sensor area in the camera (formerly the size of the image on the roll of film, of course). So with 5DII an area approx. 24x36mm or 1x1.5" is equal to 1:1 or "Life Size" magnification. Of course, it might be much larger than that in it's finished form, as a displayed print or image file posted on the Internet.

5DII is about the best Canon camera for the purpose, with the greatest amount of fine detail. (1Ds MkIII is the same resolution, some other manufacturer's cameras are higher resolution, but might lack other features).

The lens you choose is another matter. It might be several lenses, for different degrees of magnification or for other reasons. With macro lenses you also have to consider working distance... which might be limited by the "copymate" stand you are using. I'm not familiar with that particular model, but have used similar stands in the past.

Usually on a copy stand you are limited to shorter macro lenses, probably a 50mm or similar most often. A 90mm or 100mm would generally require you to move too far away from the subject, when working on a copy stand. It might not be any problem, though, if using the camera and lens on a tripod or handheld.

Canon has 50mm, 100mm and 180mm macro lenses for use on 5DII.

Also the MP-E 65mm is a specialty macro lens for higher than 1:1 magnification. It's manual focus and goes up to 5:1 mag.

Two Canon Tilt Shift lenses are also often used for macro or near macro work... TS-E 45mm and 90mm.

Almost any lens can be used for macro or near macro work, with the addition of some macro extension tubes. These increase the lens' close-focusing ability and level of magnification with it. However, it sounds as if distortion might be a problem, so a "flat field" lens design would likely be best. That eliminates a lot of non-macro lenses from consideration.

Please tell us more what distortions you are seeing, that are a problem. If it's soft focus in some areas, well when shooting macro or close-ups depth of field can be real issue. This can be offset to some degree by using a smaller lens aperture... But there is a limit to that, too. One is having adequate light to use a small aperture. Often with macro photography, you can spend an hour or two setting up the lighting, and just a few minutes taking the photos.

With small apertrures there is also an optical phenomenon with digital cameras called diffraction, where with really small apertures you start to lose fine detail. There are some ways around these things, such as using special software to do "focus stacking" of multiple shots.

Has your museum considered it might be a lot more cost effective to simply hire a professional photographer who already has all this gear and full knowledge how to use it? There is a great deal more to macro photography than a copy stand, lens and camera.

I apologize for not including more details. Here are the setting we are currently using:
ISO: 160
F-stop: 2.8
shutter speed: 1/5 (dimmest overhead lighting) or 1/25 (brightest overhead lighting)
We're using a grey digital photo card.

We are not using lighting (though we have two light boxes and umbrellas) we are adjusting the shutter speed to accommodate for the overhead lighting. This is not ideal and I would love to hear your suggestions for lighting. This has been the hardest thing to setup and to replicate. We will need to photograph 1000 birds.

The distortion happens most noticeably in the ventral view. The beak does not look flush with the color bar. I understand that if I increase the focal length, it diminishes or resolves the distortion. I was wondering if there was another way around this problem. This isn't a huge deal. If a researcher wants an accurate measure of finch beaks, s/he will probably want to come to the museum and measure them personally.

As for hiring a professional, well, of course, that would be dreamy. Unfortunately, we don't have the resources. We're a nonprofit and the equipment is on loan from another department.

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I meant to add that I really appreciate any help you can offer. Donations do not normally come with training but the expectations are still beyond what can be reasonably expected.

My recommendation will be the following:

use monolights with modifiers (doom light tent?) + F8 or F11, 125-160 shutter speed, ISO 100. Regarding lens, 50mm should do it but I'm not sure.

If you work on the copy stand you have to center your subject with the lens and make sure your camera have no tilt, a kayser offshoe level are a must for this. For my work at the museum, I use an old leitz copy stand with a manfrotto 410 head, an XTi in live view mode connected to a macbook pro. With liveview and grid on, it is easy to center the camera and subject with the table of the copy stand, For lens, I know some 1:1 lens are better, but (we are poor like many museum here) I use an assortment of cheap fixed focal lens: 28mm f2.8; 35mm f2; 50mm f1.8 and 90mm f2.8. I photography old map and artefact and never have distortion problem. I see on your picture that you have work at f2.8, maybe make a try at f5.6 to f8. For lightning, I use 3 cheap cameron socket and metal dome kit with daylight FLC (photographic FLC 5200K) shoot on white panel.

Yes, I tried to use the 100mm lens but the copy stand isn't tall enough. So I am somewhat limited to the 50mm. I can pull the camera back as suggested and crop the image. We do need significant magnification and we have been thinking of using automontage to stack images. This would slow down our workflow and we could maybe do half of the birds we originally were asked to do.

Better lighting and higher f-stop is needed to have everything in focus and better details.

Fidlina wrote in post #12426725
The distortion happens most noticeably in the ventral view. The beak does not look flush with the color bar. I understand that if I increase the focal length, it diminishes or resolves the distortion. I was wondering if there was another way around this problem.

Increasing the focal length will do nothing at all to improve perspective distortion, but moving the camera back away from your subject will. You will probably want a longer focal length to keep the framing similar from the greater distance, though. Many photographers believe it's focal length that affects perspective but they are wrong.

If you cannot afford another lens, you could still back the camera away from the subject and crop the image to frame it the way you want. As long as the camera has enough resolution to do that, the result will be quite acceptable. The 5D MkII that the sample image was made with should be fine for this as long as the display size isn't going to be huge.

As mentioned above, try stopping the lens down at least a couple of stops to get a greater depth of field and make more of the image appear sharper.

After re-reading your posts above, I see that you used a 100 mm lens as well. To get additional camera-subject distance, you could easily forget using the copy stand and mount the camera on a tripod with a horizontally mounted center column and put the subject material on the floor below it. You could even cobble together a camera stand with 2x4 wood and build your own setup for the lights.