Asa notches and Cameras

[bakanosaru]

Does anyone know which cameras can read the ASA notches?
Obviously the Beaulieus are set manually. But for the Canons, Nizos, Bauers, etc. what happens if you shoot Tri-x or some other film which is not 40asa?
Can all cameras read the notches?
Are all film cartridges correctly notched?
What can one do if you do not own a beaulieu (or leicina) and want to shoot with film with a non standard asa? Other than correct through manual aperture control and working out the difference in stops between the film you want to shoot and what your camera thinks your film is. (If I had a light meter this would solve this, unless of course my camera is auto iris only.)

Thanks in advance.

bakanosaru

[lemonhorse]

Hi All,
I just want to join in to bakanosaru's question - I'm new to Super 8 filmmaking - I love to work with this stuff - Super8 has conquered my passion! - Until now I allways have used the K40 with a Nizo S801 Camera - but I'm interessted in using the KODAK Plus-X 7276 and KODAK Tri-X 7278 (B&W) - is there something I must pay attention to (concerning the ASA value) ???

Greetings from noth Germany

- Lemonhorse

[Actor]

The ASA is determined by the width of the notch. The wider the notch the faster the film. (I think that's right; it could be the other way around.)

All of my cameras have a single pin which gets depressed when you insert a cartridge with a narrow notch. It remains undepressed if you insert a cartridge with a wide notch. Narrow notch = ASA 40. Wide notch = ASA 160.

Some cameras have more pins and thus sense other speeds. I believe the high end Canon cameras (1014 and 814) have more pins.

[S8 Booster]

Check:

http://lavender.fortunecity.com/lavende ... tspec.html

http://lavender.fortunecity.com/lavende ... ching.html

Most camras are notched for 40 & 160 ASA by befault.

200 ASA will normally be exposed as 160 ASA
50 ASA will normally be exposed as 40 ASA (Without the 85 filter)

Some higher end cameras may set 50 and 200 ASA corretly but is most likely no big deal anyway exposurewise.

R

[Actor]

Are all film cartridges correctly notched?

No.

There are no notch standards for ASA 50, 80, 125, 200, 320 or 500.

Ektachrome 125 and Vision 200T are both notched as ASA 160. Without manual intervention Ekta 125 will be underexposed by 1/3 stop and 200T will be overexposed by 1/3 stop. This is in keeping with Ansel Adams advice that if you must err in exposure it is best to underexpose reversal and overexpose negative.

I assume that if Vision 500T ever comes out in super8 it will be notched as ASA 400.

[Angus]

The better cameras have pins to detect 25,40,64,100,160,250 and 400 ASA daylight

and 40,64,100,160,250,400,640 artificial light.

I am looking at my CHinon 310 Pacific now and it has those speeds written on it. My Elmo super 110 can also detect all these film speeds.

But many cameras, even good ones, were built only to work correctly with K40 (and other manufacturers similar speed films) and E160. The Elmo 1012 s-XL is regarded as an excellent camera but it seems only to have one pin.

There is another notch in most cartridges, below the speed notch. It tells the camera whether to employ the 85 filter for daylight or not.

I think Kodak's web site sitll has the standard for the notches on it somewhere.

In practical terms it really doesn't matter much if your Ektachrome 7240 is underexposed a bit because your camera thinks it's 160ASA.

[marc]

The cameras that I have have settings for 100 asa so the 125 EKT is actally overexposed by 1/5 stop ( I think it is a fifth) which actually works out quite well. this works because the 100 notch is closer to 125 than the 160 notch.

[Actor]

The cameras that I have have settings for 100 asa so the 125 EKT is actally overexposed by 1/5 stop ( I think it is a fifth)

It's 1/3 stop.

which actually works out quite well. this works because the 100 notch is closer to 125 than the 160 notch

Photographically they are equally separated. ASA 100 = DIN 21; ASA 125 = DIN 22; ASA 160 = DIN 23. A change of 1 on the DIN scale is 1/3 stop.

I suggest you try ASA 160 and see if you like the results better. Overexpose negative. Underexpose reversal.

[marc]

I suggest you try ASA 160 and see if you like the results better. Overexpose negative. Underexpose reversal.

My personal experience bears out that this seems to hold true for Kodachrome only. Like the negative stocks, the Ektachrome comes out grainy when underexposed. My Rollei movie six registers the cartridge at the 100 asa setting and it looks great when exposed for that speed.

[marc]

What I meant to say with regards to the speed being closer to 100 asa is that the notch on the cartridge is closer to the 100 asa peg that is depressed when the cartridge is loaded and therefore sets the film speed at 100 asa by default of tripping the notch for that setting as opposed to the 160 asa setting

[Technicolor]

So if Ektachrome VNF is exposed at 160 ASA under tungsten light, what is its ASA when the 85B filter is engaged? Surely this will bring the ASA rating nearer 125 and partically solve the problem of the film being underexposed slightly.


Interesting point, I've read a lot of stills photographers underexpose their colour reversal film by 1/3 of a stop to achieve better contrast and colour saturation. I also second Actors point that is is best to underexpose reversal over expose negative film.

[marc]

So if Ektachrome VNF is exposed at 160 ASA under tungsten light, what is its ASA when the 85B filter is engaged? Surely this will bring the ASA rating nearer 125 and partically solve the problem of the film being underexposed slightly.

Yes, but the camera still only cmopensates accoding to the 160 setting so with the filter in place it is still underexposed.

Interesting point, I've read a lot of stills photographers underexpose their colour reversal film by 1/3 of a stop to achieve better contrast and colour saturation. I also second Actors point that is is best to underexpose reversal over expose negative film.

This seems to hold true for Kodachrome because of the die transfer process which adds the dies during processing and seems to mask the grain to a certain degree. Ektachrome, like negative film, already has the dies in it.

[marc]

So if Ektachrome VNF is exposed at 160 ASA under tungsten light, what is its ASA when the 85B filter is engaged? Surely this will bring the ASA rating nearer 125 and partically solve the problem of the film being underexposed slightly.


Interesting point, I've read a lot of stills photographers underexpose their colour reversal film by 1/3 of a stop to achieve better contrast and colour saturation. I also second Actors point that is is best to underexpose reversal over expose negative film.

In resopnse to your first point, yes but that compensation will still be based on the underexposure of the 160 setting and therefore will still be underexposed because the camera automatically compensates with respect to the 160 asa

secondly,

the picture quality in my opinion while overexposing Ektachrome is better as opposed to underexposing. Underexposing seems to work for Kodachrome because of the die transfer process which adds the dies during processing and seems to mask the grain to a certain degree. Ektachrome, like negative film, already has the dies in it.

I am not doubting what other photographers say, but rather, I am only making a point based on my own observations. I have also noticed that other people who complain about the 160 underexposure on their cameras have complained about how grainy they find the Ektachrome to be.

[marc]

The second entry was a revision on the previous. I guess I waited too long to edit.

[Technicolor]

Hi Marc,

I have to admit I'm still confused about the 85B filter. I know that with Kodachrome if you don’t use the filter the effective ASA is 40, and with the filter in place this corrects the color temperature for filming in daylight but also drops the ASA to 25. Is this correct?

So with ektachrome which you would expose at, for sake of argument, 160 ASA under tungsten lighting, engaging the filter would reduce the ASA of the film. But as you said, surely the meter will just compensate for the reduction light by opening up however many stops of light the filter absorbs. So how come the ASA of the film drops, or does it at all?

Also about the overexpose negative/underexpose reversal point, I wasn’t disputing what you were saying since I've never shot VNF before but it was something I'd read in a magazine. I'd read that photographers expose FujiChrome Velvia (50 ASA) at 40 or 32 ASA to get better saturation and colors, but also some photographers expose it at 64 ASA and therefore both underexposing and overexposing reversal stock provides desirable effects, depending of course on your point of view.