400 iso film vs 100 iso

hrryxgg

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hey there:

normally i use 100 film speed with my m6, and i have no trouble using the in camera meter for wide open shots at f2.4 or landscapes at f16.

today i put some 400 speed trix in there, and i am noticing that in outdoor sunny conditions using a 35mm lens that my in camera meter says all shots are going to be overexposed unless i am at f16/f22 and 1/1000.

should i be using a 50mm lens when i have 400 speed film loaded?

i hope this makes sense?

thanks!
 
Well you know with higher ASA film like a 400 speed film you have to use a fast shutter speed or stop down the lens to say f16 to control the amount of light hitting the film.
That's one reason I like 100 film. Allows me to shoot my lenses at a wide aperture on sunny days.

Wether it's a 35 or 50mm lens makes no difference. It's about shutter speed & lens aperture.
 
yes. makes sense.

i have always shot with 100 film as i do like wide open, or wider.

i guess i should stick to that?

thanks!
 
in bright sun, 400iso film, a normal exposure would be about f16 1/400

if your meter says 1/1000 you must be pointing it at the sun or the meter is wrong.
 
no, it says f16 or f22 at 1/500 or 1/1000 is about right. which makes sense.

but any stop wider makes the meter say overexposed.

and that's the issue. i like shooting wider apetures.

does that make sense!?
 
On a neutral grey subject in bright light you should get 1/500 at f16 as being about right. Likewise if you bring that down to 1/1000 at f11 its the same exposure. If you are metering off something bright, the camera will underexpose and push those settings higher.

Remember you can overexpose tri-x a atop or two no problems.
 
To maintain the same exposure, everytime you open the aperture one step (say f16 to f11), the shutter speed has increase one step as well (1/1000s to 1/2000s, which if I recall M6 does not support as it maxes out at 1/1000s). So if you really want to shoot f2.4 in the middle of the day, then your option either to use slower speed film (Likely an ISO50 film like Ilford Pan F+) or to put a 4-5 stop ND filter to reduce light entering the lens.

f16 to f2.8 is 5 stops more light which you cannot compensate by increasing shutter speed 5 steps because the M6 is limited to 1/1000s.
 
Get a neutral density filter. Even a polarizing filter will allow you to open up the lens a stop or two. 400 ASA film is almost a universal film if there is a neutral density filter available.
 
Which lens you have on the camera makes no difference at all.

Just load that thing up w/ Tri-X and shoot it at 125 w/ a yellow filter and develop it normally. Your shots will look great, and you can open up the aperture a lot more than w/ it set to 400.
 
Take a shot at the reading given by the meter; then open up one stop and take another shot. And if the meter is as extreme as f22 at 1/1000, I would take a third shot opened up another stop. Try this with several different subjects. Then check the negatives to see which exposure is best. You can even open up 1/2 stop at a time, taking 4 or 5 shots. This way you can get the correct exposure dialed in for future rolls. I suspect your meter is underexposing. If you want to shoot at still wider apertures, use a filter, or slower film.
 
To the OP's question about the appropriateness of his M6 indicating f16/22 and 1/1000s and switching to 50 I would say two things. First, it is true that with wider lenses on metered Leicas, perhaps not the M5, an increasing contribution from the sky in the field of view will direct you to underexposure. However, I find this starts to be a problem at 28mm focal length, not 35. Maybe I am pointing my M6 and 35 down slightly.....

Secondly, adjusting the ISO on the M6 sometimes results in some misregistration of the contacts, leading to nonsensical or impossible exposure indications. Toggle the dial back and forth a couple of times, ensuring it sits properly at the detente for your chosen ISO. This should lead to more sensible meter readings.
 
Hi,

I wondered about a HR caused by the mechanical bits of the circuit, meaning the ISO dial, or whatever, but a high resistance would cause something like 250th at f/16; not 1000th which suggests too much light.

Perhaps it's the sky problem as the f/16 choice suggests landscapes.

Regards, David
 
to be clear, the attempted photos were taken around 10:30am to 12:00 noon time in clear sun.

it was bright conditions.

1/1000 at f16 on iso 400 film noonish time on a bright day would be only one stop over what the sunny 16 rule would recommend for an average scene. So you are not that far off.

As other have suggested, review your metering practices. If you really want to use the built in meter of the m6, read up on the coverage pattern of the center-weighted area and point the camera so that the frame is 2/3 to 1/4 full of the primary subject matter (assuming that is what you want to be properly exposed; if you are going for a silhouette, that's adifferent story). In practical terms, for me, this often results with tiping my meterd cameras downward so most if not all of the sky is excluded. For contre-jour subjects, i stick the lens in the face of the subject, lock the reading and step back nto include the background in the frame. Switching to a 50mm makes this easier, but you should not let metering affect your choice of focal lenght.

My favorite approach, however, is to take an incident reading and never look at the built in meter.
 
well, i got up early this morning and did a short walk about, and it was overcast and gray.

the 400 film was metering to my liking at wide open apertures, meaning i think that bright sunny is not ideal for the shots i like to take using 400 ISO film.

all of this feedback is really, really helpful: thank you.
 
The reason they make different ISO speed films is for different lighting conditions. Use the appropriate speed film for the way you work. That makes more sense that using a high ISO speed film and neutral density filters.
 
The reason they make different ISO speed films is for different lighting conditions. Use the appropriate speed film for the way you work. That makes more sense that using a high ISO speed film and neutral density filters.

Exactly! However, sometimes lighting conditions aren't the only consideration. Perhaps I want a lot of grain, or maybe not, so that comes into the mix too.
For 35mm, I generally carry two bodies with different films so I'm ready for most situations.
 
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