Newcomers to 4/3


EisMann

Member
Feb 15, 2013
370
2
18
Singapore
G'Morning

Saw a video by Tony Northrup on “Do you need a Full Frame (FF)”

Using 35mm as a reference as full frame, as 1
4/3 is 2 times
Others brand is 1.6 or 1.5 times

FF Focal length/Crop Factor = Cropped Focal Length
FF Aperture/Crop Factor = Cropped Aperture
FF ISO/ (Crop Factor) 2 = Cropped Sensor ISO

The 3 formulas may be useful for newcomers for using Micro 4/3 format and manage the expectation.

To let in more light, there is this hardware I heard many times in fourms. I have no idea what it does until this morning.
MetaBone Speed Booster Adapter help to maximise the lens’ aperture to let in more light to the sensor.

The first disappointment I can gather will be bokeh photos.

You are standing next to a person shooting a subject at a same distance, using the lens with the same focal length, say 50mm with the same constant aperture, say F2.8.

You wonder why that person’s photo looks better than yours . There is nothing wrong with your gear or skill.

Just that you need to do some adjustment like taking few steps back or adjust the aperture setting of the lens to get the same effect. Or change the lens whose focal length is half of that person’s lens.

You will get the same result.


Thank You
EisMann
 

thoongeng

Senior Member
Jan 26, 2010
1,410
49
48
FF Focal length/Crop Factor = Cropped Focal Length
FF Aperture/Crop Factor = Cropped Aperture
FF ISO/ (Crop Factor) 2 = Cropped Sensor ISO

The 3 formulas may be useful for newcomers for using Micro 4/3 format and manage the expectation.
The '/' means divide by. I think you are referring to multiply by or 'X'

You are standing next to a person shooting a subject at a same distance, using the lens with the same focal length, say 50mm with the same constant aperture, say F2.8.

You wonder why that person’s photo looks better than yours . There is nothing wrong with your gear or skill.

Just that you need to do some adjustment like taking few steps back or adjust the aperture setting of the lens to get the same effect. Or change the lens whose focal length is half of that person’s lens.
Hmm think there's a bit of error here as well. Assuming both using the same 50mm lens at f2.8 aperture taking a picture at the same distance, one on full frame and one on Micro 4/3 with adapter. The photo will look the same except that the one on Micro 4/3 will be cropped to the field of view of a 100m lens.

I think most important to take photos and enjoy the process. If you like these technical details, or are very bothered by the effects on the depth of field then maybe spend more time to look into it.

Btw I though DPreview did quite a good article on the 'equivalence' topic, quite a long read though:
https://www.dpreview.com/articles/2666934640/what-is-equivalence-and-why-should-i-care
 

swifty

Senior Member
Oct 12, 2004
535
14
18
davophoto.wordpress.com
G'Morning

Saw a video by Tony Northrup on “Do you need a Full Frame (FF)”

Using 35mm as a reference as full frame, as 1
4/3 is 2 times
Others brand is 1.6 or 1.5 times

FF Focal length/Crop Factor = Cropped Focal Length
FF Aperture/Crop Factor = Cropped Aperture
OK, I see what you're getting at but the way you've quoted things is a bit in reverse to how most people denotes the equivalent apertures and focal length.
So yes, eg. 50mm lens on FF does equal the diagonal angle of view as a 25mm on m43
And yes, eg. f/2.8 on FF does let in approximately the same amount of light (total over the respective sensor size, not per unit area) as f/1.4 on m43.

FF ISO/ (Crop Factor) 2 = Cropped Sensor ISO
No, you don't divide it by the crop factor, unless you forgot the ^ symbol in your post, which you may have. You divide it by the crop factor squared.

The 3 formulas may be useful for newcomers for using Micro 4/3 format and manage the expectation.

To let in more light, there is this hardware I heard many times in fourms. I have no idea what it does until this morning.
MetaBone Speed Booster Adapter help to maximise the lens’ aperture to let in more light to the sensor.
What's happening with speedboosters or reducer adapters is you're concentrating the image circle produced by a lens intended for a larger format, onto a smaller area. It's not letting in more light, but rather concentrating the same light onto a smaller area.

The first disappointment I can gather will be bokeh photos.

You are standing next to a person shooting a subject at a same distance, using the lens with the same focal length, say 50mm with the same constant aperture, say F2.8.

You wonder why that person’s photo looks better than yours . There is nothing wrong with your gear or skill.

Just that you need to do some adjustment like taking few steps back or adjust the aperture setting of the lens to get the same effect. Or change the lens whose focal length is half of that person’s lens.

You will get the same result.

Thank You
EisMann
What you're trying to describe is the concept of equivalence and that has to do with trying to achieve the same or equivalent image when using non-equal gear, with respect to angle of view, depth of field and noise characteristics.
There's no reason that any format will produce a superior picture. All that equivalence tries to explain is, for any given format with a particular setting, how do I reproduce the same image using a different format?
 

EisMann

Member
Feb 15, 2013
370
2
18
Singapore
fty, thoongeng

Thanks for your replies.

1) "FF ISO/ (Crop Factor) 2 ........." yes it is to the power of 2. When I transferred the text fm MS Words to here, the format changes

2) "FF Focal length/Crop Factor = Cropped Focal Length...." yes it is divided. for a 50mm lens in a FF, it is equivalent to 25mm in M4/3

It is my intention to create a forum here to attack or defend M4/3 format.

When I decided to switch to interchangeable lens years, my priority was birding.
I knew what I was getting because of the physical size of the lens for the reach.

But when came to close subjects, I could not understand why I could not get those bokeh result despite using the bundle 12~40 F2.8 lens.
It was not until I read further or hunted topics in Youtube then I knew why.

Sometimes when I attended photo shoot with different formats photographers, I still heard " why my image looks different with the same setting, standing next to you"

Do I regret my choice. No, as my priority is still birding photography.
Unless I strike Toto very week, I don't think I will buy different formats for different purpose.
As thoongeng has said enjoy the process of taking photo instead.

Thank You
EisMann
 

swifty

Senior Member
Oct 12, 2004
535
14
18
davophoto.wordpress.com
Hi EisMann,
I think the equivalence topic has been used too much for such unproductive purposes as to attack/defend a format, hence I try to clarify information accuracy that otherwise adds to the confusion. I'm not in anyways saying you're attacking or defending m43, just for the record.

The recurring issue you had with fellow photographers saying " why my image looks different with the same setting, standing next to you" is precisely what equivalence is trying to explain when different formats are used. How to get an equivalent picture, nothing more and nothing less.

Anyways, I'm glad you're enjoying your equipment. As am I with my m43 equipment as well as other formats that I also use. Happy shooting :)
 

"Use the right tool for the right job." is an old saying that has great meaning for photography, especially with various digital imaging sensors. It also worked for different sizes of film.

It seems to me that people should figure out what they want to do with a camera before purchasing one. When they understand, they can buy something that works best for them.

If anyone feels the need to defend their choice, they should walk away from the computer and take photos. Any person attacking another person's choices needs to walk away from the computer and take photos. Maybe, they can enjoy each other's photos.