Sekonic L-358 Meter vs. Digital Camera For 4x5 Metering...Tonights Observations

n2mf · May 20, 2014

Using my Crown Graphic 4x5 and a polaroid 405 back, I wanted to play around with some Fuji Instant color film tonight, so I set up a scene on the kitchen table. I used my Pentax digital camera as a meter and decided on an exposure (8 sec @ f16) to set on my Crown. I took the shot and the polaroid print was pretty much exactly as I was hoping it would be. It was a very good print. So then I decided to meter the same scene with my Sekonic L-358 just to see if it agreed with the digital camera...It did not. It was telling me 4 sec @ f16, which is half the exposure time. Obviously the polaroid print would not have been as good. I bought the meter a while back but haven't used it much. But one other time I compared the readings with these two devices and they didn't agree then either. Maybe I can't trust the meter. Or maybe something isn't right about it. I took reflected light measurements.

Any thoughts on why there was so much difference?

pdjr1991 · May 20, 2014

Did you double check the settings on the sekonic?

pdjr1991 · May 20, 2014

I know it seems like a dumb question but i had the iso reset on me on a sekonic after it turned off.

n2mf · May 20, 2014

pdjr1991 said:
I know it seems like a dumb question but i had the iso reset on me on a sekonic after it turned off.

It has the capability to set 2 iso's. I have iso1 set at 400 and iso2 set at 100. The 100 reading is what I needed for the film I was using.

mgb74 · May 20, 2014

Very possibly the field of view of the meter.

Poisson Du Jour · May 20, 2014

You can trust the meter once you know what and how it is reading light, and what to do about differences.
Digital cameras, among so many others (including film cameras), use multi-pattern/matrix/evaluative and calibrated to a scale of optimal exposure for the method (digital) — at any time these meters are reading a great amount from the scene, more often than not with consummate precision. But making a reading with a digital camera and then to expect a hand-held meter to match the reading, well, the 'how and why' is because of the method being used. An simple incident reading is not the same as what the camera is reading, which is looking at several elements (light tones, dark tones, background light, spectral light, hot spots etc.) of your set up to strike an effective balance, as opposed to an overall averaged incident reading you took with the Sekonic.

yulia_s_rey · May 20, 2014

^^^+1.

summicron1 · May 20, 2014

too many unknowns to answer your question --- just the diff between reflective and incident is a consideration. What the human eye/mind finds pleasing is another unknown.

did you take a second shot at 4 seconds and compare?

n2mf · May 20, 2014

Poisson Du Jour said:
You can trust the meter once you know what and how it is reading light, and what to do about differences.
Digital cameras, among so many others (including film cameras), use multi-pattern/matrix/evaluative and calibrated to a scale of optimal exposure for the method (digital) at any time these meters are reading a great amount from the scene, more often than not with consummate precision. But making a reading with a digital camera and then to expect a hand-held meter to match the reading, well, the 'how and why' is because of the method being used. An simple incident reading is not the same as what the camera is reading, which is looking at several elements (light tones, dark tones, background light, spectral light, hot spots etc.) of your set up to strike an effective balance, as opposed to an overall averaged incident reading you took with the Sekonic.

Whats a good method of learning what the meter is reading?

grahamp · May 20, 2014

Two different meters with fundamentally different design criteria. They should agree looking at something like a smooth even toned wall. Anything else and the differences will be more apparent. They are probably both right - they are just answering slightly different questions.

n2mf · May 20, 2014

summicron1 said:
too many unknowns to answer your question --- just the diff between reflective and incident is a consideration. What the human eye/mind finds pleasing is another unknown.

did you take a second shot at 4 seconds and compare?

Since I was happy with the 8 seconds, I didn't take another shot at 4 seconds. I just assumed it would be under exposed and didn't want to waste the film to prove it. Maybe I should have.

markbarendt · May 20, 2014

All any meter ever does is provide a suggestion, when the meter is built in to the camera we do though tend to default to the camera's suggestion.

Similarly most people tend to take an incident meters suggestion as gospel. An incident meter though simply gives you an objective reference point that will place say skin tones as if they were normally and fully lit. One should ask though if that is really what you want?

shutterfinger · May 21, 2014

I set up a scene on the kitchen table.

Is one correct in assuming the kitchen table is in the kitchen? If so how large is the room whether it is the kitchen or not. What color are the walls, ceiling, and floor? What color/tone was the table? What type of lighting was used? These all affect meter readings.

I used my Pentax digital camera as a meter and decided on an exposure (8 sec @ f16) to set on my Crown.

What camera model? What lens? What metering mode? All affect the meter reading.

So then I decided to meter the same scene with my Sekonic L-358 just to see if it agreed with the digital camera...It did not. It was telling me 4 sec @ f16, which is half the exposure time.

The Sekonic has a 54° angle of view in reflective mode which is wide for a hand held meter.
The difference between a 4 second exposure and a 8 second exposure is 1 stop.

Was the meter to subject distance the same for both meters?
Was the same point in the scene used as the metering center?

The only way you can compare a SLR meter with a handheld meter and get a meaningful comparison is to use a fixed focal length, non telephoto lens on the SLR, point the two at the same subject, from the same position. The subject, if a evenly lit monotone that fills the camera frame and hand held meter angle of view should read the same on both regardless of metering mode the SLR is in. If the subject is not a monotone that fills the camera and hand held meter's angle of view then the hand held has to be positioned so that its sensor is centered on the same point the camera's reading is taken from.

A 1 stop difference between a hand held and SLR meter in a real world setting is not that great.

Search engine=google; search term= metering technique; results= https://www.google.com/search?q=met...la:en-US:official&client=firefox-a&channel=sb
Reading the first 6 to 10 links should give you a good starting understanding of metering but these are pointers. All the pointers in existence will not guarantee you great results with any meter. They will guide you to learn to meter well with the ones you have and give you a good idea of how to establish a good technique with a unknown meter.

Heinz · May 21, 2014

At 8 sec the Fuji FP has a significant correction due to Schwarzschild effect, see:

(there was a url link here which no longer exists)

So, if the exposure came out too dark, the Sekonic may have been correct, because without considering Schwarzschild effect the exposure is then too low.

NB23 · May 21, 2014

I'd trust the sekonic each and every time. But you have to know how to use it... Which relies on trusting yourself also.

And how do you know that the shot you had is obviously better? To know that you have to compare images, a thing that you haven't done.

RedSun · May 21, 2014

Get a couple of exposure, and let us know what you get.

film_man · Jun 4, 2014

n2mf said:
I took reflected light measurements.

I have a 358. To get reflected light measurements you need to use the flat attachment instead of the bulb (which is for incident). So which one did you use?

If you used the flat one (relfected), do you have a scope? If you don't have a scope I don't see how you can get any meaningful measurement as you really have no idea where the attachment is pointing and a small change in what it sees. Also, when taking relfective measurements with the Sekonic then you are spot metering. If you spot meter you really need to know what you are metering and how to compensate for a correct exposure, if you are not using a grey card.

Finally, you meter differently when using incident (walk up to subject, take a reading facing camera) or spot (stand by camera, aim at a midtone on the subject and meter that).

So, describe how you metered and we can see what the issue was.

Axle · Jun 4, 2014

Also if you have examples of the images and how they turned out to share, that would be helpful as well.

Chan Tran · Jun 4, 2014

Don't know about your exact scene it's difficult to say. It's possible that both are accurate. Perhaps the camera was on some source of evaluative/matrix metering system which give good exposure in a lighting condition where a straight reading from a 54 degree reflected light meter won't.

Prof_Pixel · Jun 4, 2014

The datasheet for Fuji fp 100c instant film calls for a 1 stop exposure increase when shooting at 4 sec, so your meter was correct. A metered 4 sec exposure would be an 8 sec exposure with reciprocity correction.

ziyanglai · Jun 13, 2014

You should take reflected light using a spot meter.. i really never figured out why they made incident meter (maybe for studio use..), but i have found that they are really incorrect.. i have little hope in them.

I know most people would probably disagree with me on this one.. But just throwing this out there. When I started, the only light meter I used were an iPhone app called "pocket light meter" and my DSLR. As dumb as it sounds, the app is surprisingly accurate. I have never, I really mean NEVER, got a bad exposure from that app, and I have missed some exposures when using my DSLR as a light meter. Few months later, I have finally decided to invest in a spot meter, and the spot meter allows me to log exposures and average it out for me. Now I'm actually using my light meter more and using my phone's app if I ever doubted myself.

Sent from my iPhone using Tapatalk

Nuff · Jun 13, 2014

I disagree, I find incident meter very accurate, it's just knowing in how to use one. I like how I can see on the white dome the shadows etc and moving it around more into shade or light to influence exposure. It's all in knowing your tools. I use Sekonic L-758D and 9.5 times out of 10, my spot metered exposure is exactly the same as my incident. There only have been very few times, where they were different and that's in very tricky light situations.

Sekonic L-358 Meter vs. Digital Camera For 4x5 Metering...Tonights Observations

ziyanglai

Privacy & Transparency

Privacy & Transparency