Tedcritch Loc: Lexington, KY

Anyone have a recommendation on self testing leaf shutter. Would like to find a portable device if possible.
Also note my budget is modest.

BebuLamar

If you go to the Photrio.com forums. There are many suggestions and DIY stuff you can build. I personally do it with what I have on hand which cost me nothing but not everyone has the things I have.

Longshadow Loc: Audubon, PA, United States

Curious - Knowing that the shutter is precisely on does what?
For 1/1000 is 1025, or 1050, or 950... not acceptable?
Why?
What difference would it make in an exposure?

Same with the exposure meter.
Just know how that camera behaves for the result one desires.

BebuLamar

I want to know that my Nikon EM gives me the correct exposure because the meter read about 1 stop low but the shutter speed is nearly a stop high and thus the error cancel out. It's important to me than just that the camera gives me good exposure.

Longshadow Loc: Audubon, PA, United States

Yup, the proper result is all I'm concerned about also.
So what if one camera is 1/1050 and another is 1/1100.
And a third is 1/964.

I wonder how many people care that their car speedometer is off. Not precise.

a6k Loc: Detroit & Sanibel

I had two Hondas which both read about 4 or 5 mph high at highway speeds. My GMC Acadia and my Wrangler both read correctly. How do I know? Well I used to use a stopwatch on the highway where there were mile posts but now I just use my iPhone for which there are various apps.

Why bother? Because I want to be able to go as fast as is legal and not worry about a ticket. Duh!

BebuLamar

In fact all 3 cameras are considered to have excellent shutter speed accuracy.
Take the Nikon F3 specification for the 1/1000 shutter speed. The aim point is 1/1024 (not 1/1000) but the acceptable range are from 1/709 to 1/1470.

a6k Loc: Detroit & Sanibel

A reasonably accurate way to check exposure, in my experience is to start with a gray card if you have one or with a piece of white paper for which you know the reflectance (see the package it came in). If you use a gray card, determine in advance if it's 18% or 12% reflectance (or whatever)

Then, on a clear day in the mid-latitudes at mid-day, carefully take some test photos of the target. I know not everyone is in the mid-latitudes but life isn't perfect.

Why those test conditions? Because the EV should be close to 14.7 (Sunny 16 "rule").

Now view the image file in any of many available viewers or editors that can show a histogram. But, in my experience, the raw image histogram shows a lower exposure (left of center) as compared to the JPG. Be aware that there is no applicable standard for raw, only for JPG.

If you used a white target you need to compensate for the difference in reflectance (example: 92% vs 18%).

This is not really perfect and you have to take care to take your test exposure without angles that distort the reading. Since most cameras show "live" exposure, you can wiggle the target to know in advance how you are doing.

This is "old school" stuff but it's still correct.

With those test conditions you can compare your camera's or meter's readings to what you know they should be and you can also check the results on your computer.

Longshadow Loc: Audubon, PA, United States

Our one car is 2 MPH high, I don't worry about it or go 2 MPH faster.
I don't need to go as fast as I can, I'll still get there.
But for some it really is about saving TWO minutes......

DirtFarmer Loc: Escaped from the NYC area, back to MA

The camera's response to exposure is nonlinear. If you can define a particular exposure as optimum, the range of exposure that will be within an acceptable range of that exposure is probably something like ± 20%. Of course some subjects will require closer exposure than that and some will not be as restrictive, but ±20% is a reasonable guess (my opinion).

So you probably won't see effects on the exposure due to excursions in shutter speed smaller than that.

A larger problem is consistency. If the shutter speed varies more than 20% between shots, then you may have a problem.

BebuLamar

1/3 stop is 26% and it's barely noticeable difference.

Longshadow Loc: Audubon, PA, United States

Varies and being "off of the dial value" are two different scenarios.

DirtFarmer Loc: Escaped from the NYC area, back to MA

Correct. I was referring to shot-to-shot variability, not calibration issues.

Longshadow Loc: Audubon, PA, United States

I never thought about that.
Not going to think (or worry) about it either.

User ID

Cannot suggest a turnkey device thaz also cheap, but if you manage to buy or build a test device, be aware that the fastest few speeds on leaf shutters should be tested at both widest and smallest f-stop, due to the reciprocating action of the blades.