Testing if Home Development is Comparable to Lab Development

I develop my C-41 at home. I use hand development small tank, Kodak LORR chemicals, precise measuring tools, and a Kodak Process 3 thermometer for temperature measurement. I think I'm pretty accurate, but lately I've become worried that I've been sacrificing the quality of color in my photos by doing home development. Are my fears unfounded? I've attached some of my photos. (poor quality screenshots, cropped)

I'd like to not have to buy control strips, which are $90 for a pack of 50. I'd like to be able to shoot two rolls of film of the same subjects, develop one myself, develop one at the lab, and compare. What would be a good set of subjects that would provide a comprehensive test? I was thinking of taking shots of my computer monitor with pictures of black and white, primary color, color wheel, various test photos... I'm not sure what kinds of photos I'd have to use.

http://imgur.com/a/iWwYa

I think your work is fine, viewed on my monitor, which I used the Windows 10 Monitor Calibration by Eyeball App to calibrate (I have an old Spyder, too, and the two are very close). Does your home process workflow use your C-41 "One-Shot", replenished or some combo of both? If so I would not overly concern myself with control strips, Control strips are best used daily, or more often in a production environment with large stable (HAH!) tanks of processing solutions. For the occasional user, one shot processing is much better (if your concern is quality rather than economy).

The following are some considerations you could use when designing your experiment into quality:

If, when you say "lab", you are talking about a custom aka production lab, by all means run your tests but look for real world tests, shoot outside at various times of day, and include gray cards, MacBeth Color Checkers, etc. in your tests. I don't think shooting targets on a monitor is structured enough.

And if you print get prints made from the lab roll and make your own prints from the home roll. If your desired end product is scans, have the lab scan the roll you send them, and then make your own scans from both the lab roll and home roll before you evaluate any scans.

But since what you are really testing is your ability to process C-41 vs. some very good lab it might be best to just evaluate the negatives. Look for physical issues. How were the negatives returned, sleeved, cut, spooled, etc. If the negatives were returned cut, how accurate was the cutting, if uncut were the negatives sleeved and put on a bobbin to protect them from the shippers or just stuffed in an envelope. Are the negatives clean, unscratched, no water drops, drip marks, or fingerprints?

Do you have a densitometer? Can you read the medium gray color channels on both films, can you compare shadow values and highlights and do some sort of rough calculation of contrast?

The tests strips for control cine process are expensive.
25 Є / 10 tests strips + reference.
With original tests strips is safety and trust.
To control the photographic process with improvised tests can say that the proposal of
darkroommike it's good.
A MacBeth scale or KODAK Color or Color Separation Guides and Gray Scales
it's good.
http://www.babelcolor.com/colorchecker.htm
http://motion.kodak.com/IN/en/motio...Separation_Guides_and_Gray_Scales/default.htm
You can look here LAD for KODAK Color Negative Film):
http://motion.kodak.com/KodakGCG/up...lugins_acrobat_en_motion_support_h61_h61a.pdf
Of course,at the natural light photography is closer to reality
but it has the disadvantage that you can not always reproduce the conditions.
The tests strips this means: a well controlled exposure to a light well controlled.
Because of this, I think improvise a place (interior) where you can take photos with a scale, under reproducible light, it could help.
The photo reproduction of a gray scale is an extremely difficult test for color films.
Problems with color balance you will see with the naked eye.
A trained eye a little can make do this without have a densitometer.
Choose a benchmark standard scale and try to replicate as closely as possible.
Observation - in a photochemical process, outside of time and temperature of the developer, a role in process is diffusion of components and therefore has formed imaging, is developer agitation.
The developer agitation did not quite measure.

George

Any daylit scene with a color chart would be good. Then you can also look at a neutral step scale.

PE

When I worked for a photofinisher that got into the one hour lab we, at first, calibrated our printers with the Kodak calibration negative sets (sort of Super "Shirley's") mostly Kodak MC-5a's (a Kodak 5s printer with a digital color control "drawer" rather than the older analog controller). We were going broke buying control sets (at least that was my bosses opinion) and started shooting our own, the advantage was our home made control sets were shot on more than just Kodak films so we could set up "channels" for Brand X films, too. (And Brand F, Brand A, Brand K', etc.) Worked pretty well but I would never have suggested making my own C-41 process control strips.

I think i'll go with shooting a color checker in incandescent light. While Portra is a daylight balanced film, that shouldn't matter. I'm just looking for consistent results between a lab and my home darkroom. It's all about the consistency.

I've never used a color checker. For a film->scan->Photoshop workflow, what should I get? Is it worth spending $70 for the official classic or $100 on the Passport (I'm still not sure what the difference is)? Or can I just get a $15 knock off.

There are 2 Kodak versions for digital that are quite inexpensive. They are both very good.

I don't advise tungsten as it will cause some problems for you due to the imbalance. Use a filter if you must use tungsten.

PE

If you say they are poor quality screen shots, then it's hard for us to judge. When I look at them I see a slight yellow cast. Now, is that you or the screen shots?

PE won't shooting outdoors introduce error? Or is it insignificant?

Andrew, I like my photos on the warm side, so maybe it's that?

What I'm worried about is inaccurate development times, temperatures, or impurities leading to malfunctioning of the color couplers. I know crossover is something that can happen, I'm just not sure what to look for.

If both films are shot outdoors, then there should be no problem. You can do it indoors with the daylight filter recommended.

PE

BySumbergsStache said:

I develop my C-41 at home. I use hand development small tank, Kodak LORR chemicals, precise measuring tools, and a Kodak Process 3 thermometer for temperature measurement. I think I'm pretty accurate, but lately I've become worried that I've been sacrificing the quality of color in my photos by doing home development. Are my fears unfounded? I've attached some of my photos. (poor quality screenshots, cropped)

I'd like to not have to buy control strips, which are $90 for a pack of 50. I'd like to be able to shoot two rolls of film of the same subjects, develop one myself, develop one at the lab, and compare. What would be a good set of subjects that would provide a comprehensive test? I was thinking of taking shots of my computer monitor with pictures of black and white, primary color, color wheel, various test photos... I'm not sure what kinds of photos I'd have to use.

http://imgur.com/a/iWwYa

Click to expand...

I only do B&W.so consider my answer accordingly.but when I started, I was terrified of doing my own film development and only trusted pro labs; today. I wouldn't trust anybody with my films.nobody can do them as well as well as I can!