Exposure Latitude

[Naughty Nigel]

I have always felt that larger formats provide greater exposure latitude than small formats such as 35 mm. This seems to be true of both film and digital photography, but particularly film.

If I use Velvia in my OM4Ti for example, I have to be very careful to get the exposure spot on, and bracketing is always wise if the photograph is of any importance. One stop either way and the photograph can be ruined. But if I take the same exposure using the same film in a medium format camera there seems to be so much more latitude. Indeed, even shots that are bracketed a stop either side of the metered exposure are normally perfectly usable.

Is this just my imagination or is there a plausible explanation?

[Ricoh]

Re: Exposure Latitude

I can't think of one. Same density per unit area, so it sort of blows it out of the water doesn't it.
For digits, easy. Bigger quantum wells, more dynamic range.

As for exposure, everyone should study the following:
http://crawfordphotoschool.com/shoot...-digital-1.php

[MikeOxon]

Re: Exposure Latitude

I have always felt that larger formats provide greater exposure latitude than small formats such as 35 mm. This seems to be true of both film and digital photography, but particularly film. ..................Is this just my imagination or is there a plausible explanation?

It could be down to the fact that smaller formats are magnified more when viewed. Edges are under less critical scrutiny, when using larger formats, and this could give an illusion of better gradation towards the ends of the exposure range.

In the case of film, there is also the effect of 'halation', where light spreads a little by diffusion in the emulsion. There is a similar 'leakage' between pixels on digital sensors. Again, this will cause more image degradation in smaller formats and, hence, could favour the gradation in the larger format image.

These are just some thoughts 'off the top of my head' and I have no experimental data to support them.

[Naughty Nigel]

Re: Exposure Latitude

Same density per unit area, so it sort of blows it out of the water doesn't it?

Yes and no. There doesn't seem to be any easy explanation but my observations are that bigger formats provide consistently greater exposure latitude.

It does occur to me that the image on (say) a 35 mm film is much more 'concentrated' than the same image on larger formats.

I also wonder what effects lenses may have. Zuiko primes are reputed to be very high contrast optics, but how this effects exposure I'm not too sure.

[Ricoh]

Re: Exposure Latitude

Yes and no. There doesn't seem to be any easy explanation but my observations are that bigger formats provide consistently greater exposure latitude.

It does occur to me that the image on (say) a 35 mm film is much more 'concentrated' than the same image on larger formats.

I also wonder what effects lenses may have. Zuiko primes are reputed to be very high contrast optics, but how this effects exposure I'm not too sure.

All I can add is that 120 and 35mm film are cut from the same emulsion stock, so # photo sensors per unit area is a constant.

[Ricoh]

Re: Exposure Latitude

It could be down to the fact that smaller formats are magnified more when viewed. Edges are under less critical scrutiny, when using larger formats, and this could give an illusion of better gradation towards the ends of the exposure range.

In the case of film, there is also the effect of 'halation', where light spreads a little by diffusion in the emulsion. There is a similar 'leakage' between pixels on digital sensors. Again, this will cause more image degradation in smaller formats and, hence, could favour the gradation in the larger format image.

These are just some thoughts 'off the top of my head' and I have no experimental data to support them.

Halation is a bonus, just love the glow it produces. In fact I have been reading far and wide seeking a film stock with the crapiest anti-halation layer known. I'm led to understand that CineStill 800 is one to try.

[Stephen_M]

Re: Exposure Latitude

Halation is a bonus, just love the glow it produces. In fact I have been reading far and wide seeking a film stock with the crapiest anti-halation layer known. I'm led to understand that CineStill 800 is one to try.

For black and white, you could try Film Washi F. This has no anti-halation layer at all.

[Ricoh]

Re: Exposure Latitude

Thanks, made a note.
Also Double X (5222), a very cinematic look to it.
https://ntphotoworks.com/product/kodak-double-x-5222/

[Naughty Nigel]

Re: Exposure Latitude

Halation is a bonus, just love the glow it produces. In fact I have been reading far and wide seeking a film stock with the crapiest anti-halation layer known. I'm led to understand that CineStill 800 is one to try.

If you are really keen, you can buy hand-coated glass slides for 5 x 4 and full plate cameras. Being hand made I would imagine you could have anything you liked within reason.

[Ricoh]

Re: Exposure Latitude

Nah, the limit for me would be rolling my own from 400' lengths of XX (also available in 100' cans on eBay). Interestingly, Eastman 5222 was used for the opening scenes in the James Bond film CASINO ROYALE.

[ame="https://www.youtube.com/watch?v=HNvzNWuzI9Y"]Casino Royale intro/opening extended cut with deleted footage - YouTube[/ame]

[mm500]

[Naughty Nigel]

Re: Exposure Latitude


Thank you Mal. So it isn't just my imagination then?

I would be interested to understand how this works.

[mm500]

Re: Exposure Latitude

Not your imagination Nigel, I'm almost sure I could overexpose by 1 stop on 120 but probably 1/3 stop would degrade the image.

Mal.