Question on Exposure using a 35mm Adapter at DVinfo.net

Shiv Kumar · September 17th, 2007, 12:55 AM

I haven't received my Letus35 FE yet but while in the process of buying lenses and since I can't seem to find the ones I'm looking for (in decent shape) I have this nagging question...Here's how it goes:

I'm assuming that I can't leave the apature wide open on the 35mm lense to the point that the image is over exposed on the ground glass and hope to correct it using the camera's apature/shutter. Is this assumption correct?

If it is then what is the reccomended way to go about setting "combined" exposure? I mean is one supposed to look at the picture and figure out that you need to close down the apature on the SLR lens to a certain point and then..

I mean how do you know where to control the exposure and how much?

Rene Roslev · September 17th, 2007, 05:38 AM

Again...I'm no expert, but..

Overexposure isn't a problem until the image is captured by the sensor/film. The adapter groundglass is just an optical element.

Usually you would want to adjust the aperture on the 35mm to control depth of field and adjust aperture on the A1 to control exposure.

The A1 (or any other camera with same sensor size) does suffer from diffraction from f/5.6 and beyond - in that case you should use ND's or stop down the 35mm lens (if you can without losing the desired look) to get optimal image quality.

David Chia · September 17th, 2007, 08:20 AM

You just got to spend abit to get a mattebox that allow you to put in a few N.D if you want to use your lens wide open. It is not adviseble to use your camera's N.D, It is the image that you want to step down before it reaches the G.G not after.

Shiv Kumar · September 17th, 2007, 09:32 AM

Rene,

Thank you for your reply. So it seems that my assumption is wrong.

From David's post (Thanks David) I get that I should be controlling the light at the source rather than after. Great information both of you.

I know what a matte box is but I don't own one. Plus they seem bulky (light weight possibly). Can I not just using an ND filter (possibly have to buy a variety of them and stack them to get different stops. Or is there a benefit to a matte box over filters.

What I think this (both your answers) does is (I think) give me the option to buy the AF lenses instead of hunting for the older (no longer being produced) MF lenses. But since these will be wide open I can controll the light using filters/matte box. Is that correct? Or am I just going about this the hard way?

Another question just popped up in my mind. I know you can control the DOF with the apature. But having a wide open apature (but controling the exposure using ND filter/matte box.... is it going to give me a shallow DOF none the less (because the apature is wide open). That might not be a good thing (in many situations).

On e-bay (having spent days finding, monitoring and bidding) I find that these older lense are almost as expensive as the new AF lenses. I get the feeling that (from various things I've read on the Internet) that the older lenses are better quality or something. AI-S is better than AI and two 85mm lenses (identical in specs) are not the same because of the year they were manufactured in or their serial numbers are not within a certain range.

And I'm not even a Nikon user. Heck I've just been taking Photos as a Hobby using a cheap Canon EOF for a few years :)

September 17th, 2007, 12:55 AM	#1
Shiv Kumar Major Player Join Date: Jul 2007 Location: Gainesville, VA, USA Posts: 327	Question on Exposure using a 35mm Adapter I haven't received my Letus35 FE yet but while in the process of buying lenses and since I can't seem to find the ones I'm looking for (in decent shape) I have this nagging question...Here's how it goes: I'm assuming that I can't leave the apature wide open on the 35mm lense to the point that the image is over exposed on the ground glass and hope to correct it using the camera's apature/shutter. Is this assumption correct? If it is then what is the reccomended way to go about setting "combined" exposure? I mean is one supposed to look at the picture and figure out that you need to close down the apature on the SLR lens to a certain point and then.. I mean how do you know where to control the exposure and how much?

September 17th, 2007, 05:38 AM	#2
Rene Roslev Regular Crew Join Date: Apr 2007 Location: Copenhagen, Denmark Posts: 49	Again...I'm no expert, but.. Overexposure isn't a problem until the image is captured by the sensor/film. The adapter groundglass is just an optical element. Usually you would want to adjust the aperture on the 35mm to control depth of field and adjust aperture on the A1 to control exposure. The A1 (or any other camera with same sensor size) does suffer from diffraction from f/5.6 and beyond - in that case you should use ND's or stop down the 35mm lens (if you can without losing the desired look) to get optimal image quality.

September 17th, 2007, 08:20 AM	#3
David Chia Major Player Join Date: Nov 2006 Location: Singapore Posts: 427	You just got to spend abit to get a mattebox that allow you to put in a few N.D if you want to use your lens wide open. It is not adviseble to use your camera's N.D, It is the image that you want to step down before it reaches the G.G not after.

September 17th, 2007, 09:32 AM	#4
Shiv Kumar Major Player Join Date: Jul 2007 Location: Gainesville, VA, USA Posts: 327	Rene, Thank you for your reply. So it seems that my assumption is wrong. From David's post (Thanks David) I get that I should be controlling the light at the source rather than after. Great information both of you. I know what a matte box is but I don't own one. Plus they seem bulky (light weight possibly). Can I not just using an ND filter (possibly have to buy a variety of them and stack them to get different stops. Or is there a benefit to a matte box over filters. What I think this (both your answers) does is (I think) give me the option to buy the AF lenses instead of hunting for the older (no longer being produced) MF lenses. But since these will be wide open I can controll the light using filters/matte box. Is that correct? Or am I just going about this the hard way? Another question just popped up in my mind. I know you can control the DOF with the apature. But having a wide open apature (but controling the exposure using ND filter/matte box.... is it going to give me a shallow DOF none the less (because the apature is wide open). That might not be a good thing (in many situations). On e-bay (having spent days finding, monitoring and bidding) I find that these older lense are almost as expensive as the new AF lenses. I get the feeling that (from various things I've read on the Internet) that the older lenses are better quality or something. AI-S is better than AI and two 85mm lenses (identical in specs) are not the same because of the year they were manufactured in or their serial numbers are not within a certain range. And I'm not even a Nikon user. Heck I've just been taking Photos as a Hobby using a cheap Canon EOF for a few years :)