Facebook photos and high school algebra

When I get around to uploading phone camera photos to Facebook, I start off by looking at the twenty or so photos I've taken since last time, and end up actually uploading a fairly small fraction (perhaps a quarter?) of them. Somewhere in between that, I need to spend some time in Photoshop (i.e. the just-as-good open-source program, GIMP) compensating for how terrible all my phone's photos look.

Let $N$ be the original number of photos, and $M$ be the number of photos worth keeping.

My old Facebook photo uploading workflow:

• Hand-pick the photos that will probably look nice after touching up. (Estimated time: $0.1N$ minutes.)
• For each photo I want to use, open it in GIMP (i.e. Photoshop but free). Auto-correct the colour in GIMP. Play around with contrast, saturation and cropping settings in GIMP. (Estimated time: $2.5M$ minutes.)
• Upload those photos to Facebook. (Estimated time: $0.1M$ minutes.)
• Add captions, dates, tags, etc. (Estimated time: $0.5M$ minutes.)

Estimated total time: $0.1N + 3.1M$ minutes.

E.g. typical upload spree (20 original photos, 6 actually uploaded): 20 minutes.

My new Facebook photo uploading workflow:

• Upload all the photos to a private Google+ album. (Estimated time: $0.1N$ minutes.)
• Hand-pick the photos that look nice after Google+ applied Auto Enhance to them. Download them back to my computer. (Estimated time: $0.3N$ minutes.)
• Upload those photos to Facebook. (Estimated time: $0.1M$ minutes.)
• Add captions, dates, tags, etc. (Estimated time: $0.5M$ minutes.)

Estimated total time: $0.4N + 0.6M$ minutes.

E.g. typical upload spree (20 original photos, 6 actually uploaded): 12 minutes.

Discussion

Rough analysis suggests that the new method saves time when:

$$\begin{align} 0.1N + 3.1M &> 0.4N + 0.6M \\ \Leftrightarrow 2.5M &> 0.3N \\ \Leftrightarrow M &> 0.12N \end{align}$$

So if I have twenty photos and only one of them is any good, I'd be better off doing the GIMP method than wasting all my time going through Google+.

Further research

• How much time will it save once I set up my phone to sync my photos with Google+?
• If/when Facebook rolls out photo enhancement technology, how much time will I save directly uploading to them?
• Is $M$ independent of the method I use? E.g. am I subconsciously happier to select more photos using the "new method" because I know it'll take less time-per-photo-used?

#science