Newbie development question: how dark should the sprocket area be?

Hi All,
I am starting to use Caffenol and have to adjust my process (I am also pretty new to home development) to suit Rollei Retro 100. I have found references that say I should develop for 15 mintutes. However, my negatives are a bit dark- should the sprocket area be relatively clear? The sprocket area and the gaps between images that are grey.
I am not refering to scanned negatives.

I have two (hopefully) simple questions:
1. How dark should the sprocket area of a film negative be if it is correctly developed?
2.If the grey negative is an issue, do I develop for a shorter time, or a longer time? - I know this should be obvious, but I am confused.

Again - Just to be clear - I am refering to the actual negative film being rather grey (is this called a thick negative?).
Best regards,
Mark

Here is an unedited scan of a negative from my current process (only cropped)...

Depends a little on what you call grey.
The sprocket area should be clear or close to it, the frame number markings should be easily visible.
If it is grey then it's a sign the film has been fogged.
A scan showing the full width of the film, and preferably more than one frame would help.
The scanned negative looks to have fairly low contrast. Though many things can cause that, fogging is one cause.

Not very. It depends on the film. The sprocket area is unexposed film, and it should have the density of the base plus fog. You should not have any significant fog with well kept film and a good developer. The base density depends on the film and may be anything from clear to a light gray (maybe 0.3). Fix out a small piece of undeveloped film to determine what you should expect. (A half an inch from a leader will do nicely.)

Remember that Caffenol, while fun, is not optimized for a particular activity level. In my limited experience with it, it tended to produce a lot of fog and low contrast, which is what you're experiencing. The only way to overcome this problem is to chemically alter the developer to reduce fog.

The major determinant to the density of the unexposed film base will be age related fog. Some developer combinations can minimize the fog but maybe at a loss of speed.

You can always print 'through' fog in film with good results, whereas fogged paper is spoiled.

These are great tips - I dod not realize what fog looked like (Ok, i'm new to this). Adding KBr to the Caffenol will apparently reduce fog. I will try that.

Caffenol-C rather than Caffenol might be better. Depends on the film as to how much base fog you get. I use Fomapan 100 and Efke pl50 with Caffenol-C with good results. High speed film doesn't work with caffenol-C; too much fog, but there are variants that address that. I think unless you are looking for a particular result from using a Rollei film with a manufacturer specified developer, it's an expensive film to play around with. Using a more common film might be more useful for playing with.

if you are new to developing film, I suggest you start with a more "serious" developer to get a hang on this. Start with a developer with known developing times, depending on contrast, and agitation.
To start the right way, make notes of every film you develop, including time temperature and agitation. Shoot several films of the same subject using the same exposure values if possible, make notes of these too, and compare those.
After some time you will be able to develop good results, even with Caffenol.
Framenumbers should be sharp, colour depending on film type and developer, but not too dark, the leader of the film, when held against a lamp with white light, must have enough transparancy to see the white light.
Sprocketholes should be no darker than the white on your developed film, if you got signs of darkened swirls around the sprocketholes on your film, than the film has got too much agitation during the development.
Also keep in mind that over-development, to much agitation, temperature to high, development time to long, will cause the darker elements too develop further while the lighter elements will stay behind and produces a greyish film.
One more thing, if loading the film in the tank, make absolutly sure that no light can reach the film.

Happy developing and show your results please.