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Solicitation for comments on SERNEC live plant image standards


1. This is a solicitation for comments regarding proposed standards for photographing live plant images.  These standards are outlined at:
2. These standards are being considered for adoption for use in a live plant image collection of SERNEC (the Southeast Regional Network of Expertise and Collections). They are intended to guide the collection of new images to be included in the SERNEC collection.  Extant images that don't meet the standards may still be included in a "legacy" SERNEC collection. 
3. The standards for herbaceous angiosperms, woody angiosperms, and gymnosperms are fairly "mature" and probably close to ready for adoption, in contrast to the cacti and fern standards which probably need to be looked at by specialists in those groups before they are ready to be adopted.  So at this point, let's limit the discussion to the first three categories. 
4. Please make initial comments by Nov. 1, 2008.  The comments will be compiled for further discussion by those who wish to do so.  Please email comments to and indicate the question to which you are responding.


1. The standards are intended not only to produce standardized orientations of plant parts  and to ensure that detailed images are collected of the features that are important for identification, but to facilitate rapid image collection under field conditions and to minimize the need for image manipulation during later processing. 

2. Our primary purpose is to agree on standards for images that will be used to facilitate species identification and recognition and to be used as an educational resource.   If there are competing considerations between these uses and others such as artistic or commercial uses, the educational considerations trump the others.

3. We are talking about the images that will be archived to serve as raw materials for other uses.  We want to preserve the capability for these images to be used for as many other uses as possible.  So even though modifications of the images such as creating composites of several features, writing the species name on the image itself, adding borders, etc. may be desirable for some uses, they would preclude other uses and are therefore not appropriate.  Such modifications can be made on secondary products (e.g. publications and websites) that use the archive as a source.



1. Background of images. In the images standards paper [Baskauf, S.J. and B.K. Kirchoff (2008) Digital plant images as specimens: toward standards for photographing living plants.  Vulpina 7:16-30.], for close-up images we suggested using the combination of narrow aperture (i.e. high f stop), high shutter speed, and flash to allow for wide depth of field (all details in focus), reduced blurring due to motion of a hand-held camera, photography under low ambient light, and to produce a dark background that reduces distraction. See for examples.

A. Are there reasons (practical or philosophical) NOT to do this? 

B. Should the background be white instead of black, and how can that be achieved?
See for an example.

C.  Are there enough advantages of natural lighting to override the advantages of flash?  What are those advantages and what are the costs in terms of time and equipment to take good natural-light images?


2. Non-self-supporting objects. If it is not possible to photograph an object that will support itself (e.g. the only fruit available to be photographed is on the ground), how should the object be photographed?  Holding it in the hand is easy, but has a distracting hand in the picture.  Putting it on a black background reduces distraction, but requires carrying the background with you and has potential glare problems.  Photographing the object on the ground looks more natural, but may produce a distracting background.  See for examples.


3. Twigs and buds.  The provisional standards specify that twigs be oriented horizontally (because that is generally the way they appear on the tree) and that closeup images of buds/leaf scars on winter twigs be oriented vertically (because that's usually the way they appear in line drawings in twig keys).  See

A.  Does it make sense to have these orientations or would it be better to have all orientations be vertical with the apex to the top?

B. If the overall twig orientation remains horizontal, should it be specified that the apex always be in a particular direction (e.g. toward the right) or does this not matter?

C. Because winter buds are an important identifying characteristic and can be observed with a hand lens, they could be an important part of an image collection.  However, because they will probably have to be photographed under a microscope, they fall beyond the general category of features that can be rapidly photographed in the field with a hand-held camera.  Are they an important enough feature that they should be kept in the standards or are they a specialized feature that falls beyond the scope of this project?

D. Are there too many gymnosperm twig/needle categories?  Images which show one feature often show the other as well (e.g. needle bases and twig showing attachment of needles - can some categories be combined?  See


4. Seeds.  Seeds are often small enough that they cannot be photographed well without using a microscope.  They also may need to be extracted from the fruit.  If small and outside of the fruit, they become non-self-supporting objects.  See:

A. Are seeds a taxonomically important enough feature to be included in the standards as an object themselves to be photographed outside of the context of the fruit? 

B. If seed photography is included in the standards, how should they be photographed? 

C. If seed images generally need to be made microscopically, does this put them outside the scope of this project (i.e. images that can be taken in the field rapidly with a hand-held camera)?


5. Leaf orientation on herbs. The provisional standards have upper stem leaves oriented with the apex upward and basal/lower stem leaves oriented with apex downward.  This was chosen because that seemed to most closely mimic their typical orientation on the plant.  See

A. Would it be better to have all of the herb leaf images oriented in the same direction (e.g. apex down as is the case with woody leaves) or should the standard remain as it is?


6. Habit/habitat shots.  There is no specific standard indicating that the plant should be photographed in the context of its environment (e.g. a distant shot for small plants). See

A. Is this an important-enough view that it should be included as a separate standard, or should it just be an optional addition to the whole plant image category?


7. Superfluous, missing, or inadequate standards.

A. Are there standards that you feel are unnecessary?

B. Are there standards that are not on the list that you think should be added?

C. What standards are in need of change?