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joelorbita
20-Jul-2010, 08:48
Hi, I realise that this question has somewhat been addressed before but I couldnt find the specifics so I apologize in advance if I am going over old territory. I use a Chamonix 45N-1 with a variety of lenses and generally have no problem getting correct exposure during daylight but at night it is sometimes off. Also, at night there seems to be a lot of variance with light trails of cars etc etc.. I know that digital relates differently to film with regards to long exposures but I was wondering if anyone has done any tests between their digital camera and film and then use that as a guide for night exposures? Is there any consistant relation or are there too many variables? Also, am I right in assuming that shutter sppeds are the same across ALL cameras, regardless of format? Same applies to aperture? I realise the depth will be different as you change between formats... Also, if smaller camera only go to say f11 ( like a lot of smaller ones do ) is it just a matter of adjusting for this?

So mainly I am after a small digi to gain an idea of movement in shots (both day and night) and to get some indication of night shots?

Any thoughts or suggestions? I am already carrying around a bit of gear so the smaller the better really that still gives good results..

Ok, thanks so much in advance for any thoughts or suggestions. Regards Joel

SocalAstro
20-Jul-2010, 08:57
Hi Joel,

I do exactly what you are describing with my canon 5DII as a long exposure meter for my film shots.

One thing to consider is that the digital camera will have a linear response to low light - i.e. no reciprocity. This means that you'd have to compensate the film exposure accordingly. This may give a completly different look (trails, motion) if the film exposure is longer than the digital. The way around it would be to use film that has good reciprocity characteristics so the exposures would be the same on both digital and film (up to a couple of minutes at least). I like Fuji Acros, Tmax 100 for B&W, and E-200 (120/220) and Provia/Velvia for color

-Leon




Hi, I realise that this question has somewhat been addressed before but I couldnt find the specifics so I apologize in advance if I am going over old territory. I use a Chamonix 45N-1 with a variety of lenses and generally have no problem getting correct exposure during daylight but at night it is sometimes off. Also, at night there seems to be a lot of variance with light trails of cars etc etc.. I know that digital relates differently to film with regards to long exposures but I was wondering if anyone has done any tests between their digital camera and film and then use that as a guide for night exposures? Is there any consistant relation or are there too many variables? Also, am I right in assuming that shutter sppeds are the same across ALL cameras, regardless of format? Same applies to aperture? I realise the depth will be different as you change between formats... Also, if smaller camera only go to say f11 ( like a lot of smaller ones do ) is it just a matter of adjusting for this?

So mainly I am after a small digi to gain an idea of movement in shots (both day and night) and to get some indication of night shots?

Any thoughts or suggestions? I am already carrying around a bit of gear so the smaller the better really that still gives good results..

Ok, thanks so much in advance for any thoughts or suggestions. Regards Joel

Jack Dahlgren
20-Jul-2010, 15:30
Hi Joel,

I do exactly what you are describing with my canon 5DII as a long exposure meter for my film shots.

One thing to consider is that the digital camera will have a linear response to low light - i.e. no reciprocity. This means that you'd have to compensate the film exposure accordingly. This may give a completly different look (trails, motion) if the film exposure is longer than the digital. The way around it would be to use film that has good reciprocity characteristics so the exposures would be the same on both digital and film (up to a couple of minutes at least). I like Fuji Acros, Tmax 100 for B&W, and E-200 (120/220) and Provia/Velvia for color

-Leon


Leon, the reciprocity data published for Tmax indicates that your statement that they are the same for "a couple of minutes" is optimistic.
http://www.kodak.com/global/en/professional/support/techPubs/f32/f32b.jhtml
But I completely agree that those films are better than many others.

The good thing is that reciprocity information is usually available and you can pretty easily adjust for it.

SocalAstro
20-Jul-2010, 21:29
Thanks for catching that Jack. Acros 100 is my favorite for low light shooting. I knew T-max needed a little adjustments - 1 stop more is not too bad for 100s :-)

I tend to bracket +1, +2 stops for night shots anyway :-)

-Leon


Leon, the reciprocity data published for Tmax indicates that your statement that they are the same for "a couple of minutes" is optimistic.
http://www.kodak.com/global/en/professional/support/techPubs/f32/f32b.jhtml
But I completely agree that those films are better than many others.

The good thing is that reciprocity information is usually available and you can pretty easily adjust for it.

dave_whatever
21-Jul-2010, 02:33
Although not LF I used a digital SLR to meter for night shots on my mamiys 645. To make like a little quicker I metered the shot wide open at f/2 (i.e. so i didn't have to wait 10 minutes to take a "reading" at f/16) and just multiply it up to the shooting aperture/ISO on the mamiya. Worked fine.

Any micro m4/3rds camera would be fine for this (as would many digital compacts), although be aware the lenses will probably stop at f/16 instead of going directly to smaller apertures, so if you shoot a lot at f/22-45 be ready to do a bit of mental arithmetic regardless.

Jeff Keller
21-Jul-2010, 14:30
I've seen many posts saying that many lenses don't have accurate aperatures wide open. Digital cameras will also respond to UV different from film. ... But I use a digital camera as an exposure meter and see no reason to change. Adjusting for different ASA, shutter speed, and aperture settings does not cause problems. Using a zoom lets me see a histogram of the scene I intend to capture with film.

A nice thing about the micro 4/3 cameras is that many different lenses can be adapted to them.
Jeff Keller

ki6mf
21-Jul-2010, 19:17
For black and white f 22 5 minute exposure or F 32 for a 10 minute exposure and you must use a compensating developer like D 76 diluted 20% developer and 80 % water. 2 minutes between agitation. This covers reciprocity failure and lets you have a negative that can be corrected in the darkroom. Experiment with other compensating developers like HC110 in a two step water bath process. Keep rigorous notes on all aspects of your development and exposure because that is the only way to develop a sense of that the proper camera settings should be for the quality or light your ae shooting in.

For Color pick a aperture you like, set the lens to T for Time, take a stop watch, an make expose for various time periods in sequence: 1 Minute 2 minutes, 5 Minutes 10 Minutes then have film developed. Print. You cant measure light at night and keeping a journal of what the light conditions were like is the only way to determine what your exposure should be to get an accurate negative! You must keep rigorous records and remember what the sky was like in order to get your negatives right.

Best source for night photography Film or Digital is the Nocturnes at http://www.thenocturnes.com/