The need to produce quality prints or digital images is vital to an artist's career, especially early on when the engraver needs to build a portfolio of their work. Some magazines require that you use trade photography services they work with while others allow digital or hardcopy submissions as long as it meets their format criteria; it's best to contact the publication and ask.
As an artist you will likely attend trade shows and even if you do not, you will be required to promote yourself in some manner such as the web... In either case you will need photos of your finer work either digital, hardcopy, or both, and if possible HD videos would be an an added bonus.
Avoid displaying incomplete work unless it is a current work in progress. If you must display incomplete work it is wise to keep it to a single item unless multiple parts belong to a single project. Otherwise you may run the risk of sending the wrong message that you begin projects but may not complete them. This is only true when photos of ones work are few or when aspiring to have a career in this field and are working towards recognition. Once we are established with a large body of work to draw from the aforementioned is not a hindrance.
Professional photo services can be very expensive so much so that most new engravers simply cannot justify the cost of one single print let alone a series of prints that are needed for every job. Early commissions rarely pay handsomely enough to be able to spend hundred on a few photos.
For self promotion digital images most times suffice and offer the ability to edit backdrops colors or imagery and provide a more beautiful overall photo. Photos should always be clear and sharp and properly focused with colors that are reasonably accurate. Our best assets will always be our skills, and the more control we are able to exercise over our self-promotion the easier it is to command our destiny.
Professional photography services are excellent at what they do and will automatically submit a copy to the appropriate magazines as part of the overall fee and is the method of choice if one desires to see their work in publication providing that the magazine has an interest in your work.
Therefore, like search engine submission, do not expect that submission to a magazine means inclusion, it generally does not. On the other hand, for those with strong digital skills and some photographic knowledge much can be achieved with very little.
Maximize your abilities and avoid financial risks early on, instead rely more heavily on your skills. Never fear rejection, do the best you can with what you have always insuring your customer and their property come first. Finally, submit your work when possible to only receptive sources that you know welcome them or you have contacted before hand.