You are here:

Photography/Shooting 35mm negatives (macro)

Advertisement


Question
Dave, i'm converting 35mm negatives to digital by shooting macro in a dark room, inverting, post-processing raw. The end result is very good. I first tried with a small sensor compact (minimum focus distance 1-2cm) but the lens is not sharp at ~F3.5 wide. Then tried 14mm F2.5 u4/3 lens (minimum focus distance 13cm, much sharper image) and its the best i have. This cam is only 12mp, so by the time i crop and post-process the final jpeg is ~300-400kb size. I was wondering if it would make a difference in image size and detail if i upgrade my current interchangeable lens system to a different brand 20mp APSC sensor + 9-27mm F3.5-XX minimum focus distance 14cm.

I imagine the final image will be larger because of the sensor and would probably have more detail, compared to 12mp, but i don't know if one stop makes a difference in this case, or even worth upgrading. I'm not a pro.

Thank you.

Answer
Yes, having 20mp instead of 12mp will improve the resolution of the digital file.  But I think you are looking at the f stop rating the wrong way.  Your f 2.5 or f 3.5 is the widest opening available for that particular lens, and is used when you have minimal light.  (A lower f stop number means that the aperture opening is wider. All other things being equal, a lower f stop rated lens is larger and more expensive.  I used to have a Minolta lens with f 1.2, which was a larger diameter lens than usual, and very good for low light.)  But for a finer focus over the width of the image, it would be better to stop down to a smaller f stop (a higher f number, like somewhere between f 16 and f 22, for example).  The various parts of the image are different distances from the lens when the subject is close to the lens.  A smaller aperture provides more depth of field, so the complete image can be in better focus.  Since you will have the camera in a fixed position (such as on a tripod with remote release), you can adjust the shutter speed to be slower as may be needed for proper exposure.

Hope this helps!

Dave  

Photography

All Answers


Answers by Expert:


Ask Experts

Volunteer


Dave Nyce

Expertise

I have used SLR cameras for 30 years and have taught classes on photography at work for my co-workers. I had a darkroom for 20 years, but now am using mostly digital cameras. I can answer questions on equipment and techniques for photography, but am not an expert on specific model numbers of cameras or accessories.

©2016 About.com. All rights reserved.