Physiograms - Using light to "paint" lines onto film - In a darkened room exposing film to sharp points of moving light to create unique patterns of light on film (very basic definitions).

These images require long exposure times and the ability to lock open the shutter. To some extent you can get this effect with moving lights and just long exposure times. We have all seen these types of images. An example was my submission to the September challenge. The moving cars created this type of movement lines.

My question is this: With most Prosumer digital cameras and point and shoot cameras there is no way to lock open the shutter (not the case with full body digital SLR's). How then can a person using a digital camera create this effect?

In a book by Lee Frost (The Complete Guide to Night & Low-Light Photography) he has a small section on using different types of light to paint a photograph. One example is using a penlight to "trace" the outline of shoelaces (page 181 if you have the book), and the ambient light creates a wonderful effect. In others he uses sparklers and other sharp light sources.

With the limitations of Prosumer and lesser digital cameras is this even possible? If it is possible, how can I achieve this type of effect?

Being a total amateur, I had to make choices when buying a camera. I chose digital for a lot of reasons: overall costs, flexibility, and ability. I know that I have talent with Photoshop and that I can fix a lot of imperfections. Other main reasons are that I don't have the resources to develop film, the space for a dark room, nor the money to have someone develop it for me. Hence I am limited to digital. I also understand that there are limitations to digital; I just refuse to accept limitations! I do things in my life that can't be done because no one ever told me they couldn't be done!

Am I pushing the envelope a bit too far on this one?

Magick Michael
aka zhounder

Don't know - just a thought. I don't shoot digital, so this suggestion may be completely useless - but what is the auto-exposure range (in secs) of your camera? If you piled a bunch of ND filters (or even an unexposed but processed piece of transparency film) in front of the lens, would the exposure time be great enough to achieve the effect? (May get your exposure times down to 10 or 15 seconds...?)

thats an interesting idea... and should work as long sa your digital camera is less poor than my cmos sensor 640x480 offering... i still use my good old slr :) digital would be very good for this, as it is a hard trick to get right. you are going to need some way of fixing all those ND8's on however...

OK I am going to show my ignorance here. How does adding ND filters speed the exposure time? I can figure out a way to get them on, that is just a matter of perseverance. My problem is that I don't have the knowledge of filters at all to understand how that will work. Please bear with me in the fact that I am a total amateur with zero photographic education. All I know I have taught myself or learned by reading. Sorry for the stupid part of this question. Magick Michael aka zhounder

One other note. The max I can get out of the camera is 30 seconds and that takes some doing. The shot that I used in last months Challenge was 22 seconds. Magick Michael aka zhounder

ND filters (Neutral density) are filters that cut the light intensity without altering the color,etc. of the scene. I don't remember the math, but I think a ND8 will cut your exposure time 4 stops (from, lets say 1/4 sec to 2 sec) - they're usefull when, for example, you want to show the blur of a waterfall in a fairly bright situation but the slowest shutter speed you can get is, say, 1/60 sec (a really bright day!) the solution is to put a pair of "sunglasses" on your lens (ND filters) - cuts back on the amount of light, allowing for slower shutter speeds, ND8 would give you 1/8 sec (there again, don't remember the math...help?) A blank piece of film over the lens would cut out a bunch of light, but the exposure time would be a matter of experimentation (used to use a couple of chunks in the viewfinder to shoot eclipses (sp?)...or ignore this - I've had a couple of beers (x7) :^)

I own an Pentax IQ zoom 105. It's a point and click. HOWEVER I am able to photograph in "BULB" mode and leave the shutter open for 1 minute. Additionally there is a cable which allows me to open the shutter as long as I want. The camera is able to perform mutiple exposures also. I assume many of the higher end point and shoot cameras have this ability. With respect to digital cameras. If I am correct Zounder what you are refering to in the darkroom is called dodging and burning. Digitally this effect can be replicated using a didge and burn too/brush. I can do this in Paint Shop Pro so I would expect this to be available in Photo Shop. Did I address the correct question? Bsteph

bsteph2069 I do understand that I can get a similar result in photoshop. I was hoping to do this witht he camera however. The possibilities go beyond Dodge and burn. The book mentioned in my original post points to where the author used a penlight to actually trace the shoelaces on a pair of old boots and the luminary effects where the actual overflow of light was show really created a fantastic image. In part yes you did answer the question. Thanks! Magick Michael aka zhounder

30 secs should be enough... it may take a fair amount of ND filters to ge that low down though. as far as i know, an ND 8 just allows through 1/8 of the light, ND4 1/4 of the light ND2 1/2 of the light. that could be me remebering wrongly - i havent got my book to hand.