Proper Exposure Compensations

To all:

I am new to LF photography and wanted to find out if there is something out there that can help me in the processes of coming to the proper exposure for a particular scene. I am becoming more familiar with the zone system, and if I understand correctly, can apply that for color trannies as well (correct me if I am wrong, and if wrong, what do others do?) If there is a better method, what is it?

Even a bigger issue is the compensations needed for bellows and/or reciprocity effects. There is a lot of "you need to make the proper adjustments" kind of statements but have not been able to find specific instructions on how you come to know what those adjustments should be. I know that my ignorance is really starting to shine here, but it is a little confusing on how to come to know in terms of "time" what those corrections are. For instance, in Jack Dykinga's book "Large Format Nature Photography," he explains that if you determine that you have a 9 second exposure (I expect taken from a reading of the spotmeter and determining where he wanted to place that value zone-wise) that he would need to make a color correction due to the length of the exposure by using a Tiffen 812 or 5 magenta. A question in my mind asks where do you draw the line? When, in terms of the time of an exposure, do you determine that color correction will be necessary? I know that this is film specific, but that is the issue. If I am using Velvia 50 when?, using Provia 100 when? 100vs when? Then, when I've made the color correction, of course I need to make the exposure correction for the filter. He stated that he needed to make a 3 second compensation. How did he come to that? I know that filters all have their correction values but didn't think that equated to that long of a correction(1 or 2 or even 3 stop correction values for a filter doesn't necessarily equate to a full 3 seconds). After that, due to the length now in exposure of 12 seconds, you need to make a correction for reciprocity failure of 5 seconds. How did he come to that figure? I know supposing he is using Velvia, that that film at that exposure length requires a correction of between +1/2 to +2/3 stops. I guess I'm not quite understanding the relationship between the required stop and what that equates to in time (and I haven't even gotten to bellow factoring yet!!!)

I know that this is a very long, exhausting post and really exposes my ignorance so I really appreciate everyone's patience. Could someone please shed some light on this or at least a really good resource that I can get my hands on to help me understand these concepts?

Thanks!

Reciprocity failure data (including filtration) is included in the data sheet for each particular filmstock.

With some films, Fuji Provia, Astia, you are good to 2 minutes without any compensation:

http://www.fujifilm.com/products/pro..._datasheet.pdf

Calumet has a device to simplify bellows compensation:

http://www.calumetphoto.com/item/CC9201/

There is also the "quick disc" found online.

Jason Bruner's thingy is pretty cool. http://jasonbrunner.com/files/jbbellows.pdf

I agree with the quickdisc:
http://www.salzgeber.at/disc/

It is a part of the standard accessories with my LF-gear. I use it all the time and it takes a lot of thinking off my allready overloaded brain. Just measure the circle on the GG and read off the compensation factor. Depending on how the disc is laying it can have an eliptical shape, so remember to measure the longest part of the disc.

A few times I have forgotten to remove the disc before making the exposure. Always annoying. :mad: