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What is the medium format 'compression'?

HarisF1
Posted 06/01/2019 - 16:50 Link
Here are three images. They've been snapped with three different lenses on three different cameras. One of them happens to be medium format. I tried to keep exposures in check but varying lighting conditions didn't help. I've cropped them so that the FoV is similar.

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The most noticeable thing about the three images is that I can't see any major difference in the images in terms of they way they look. The idea of 'compression' isn't really visible.

Here are a few questions to hopefully create a nice discussion on an otherwise depressing Sunday (school's back tomorrow):

1) Can you guess which is the MF image, and maybe the formats and lenses used for the other images too?

2) Why would someone pick MF over FF or APS-C?

3) What is the fabled 'medium format look'?

4) If there's no obvious difference in images like this, why do people spend so much money on the next big thing?
All the gear with no idea
Edited by HarisF1: 06/01/2019 - 16:56
derek897
Posted 06/01/2019 - 17:02 Link
images are a tad small when you click on them to be able to look at them properly, any guesses of mine are just that, guesses. The image doesnt really help either
1 mf
2 ff
3 Q

Ive never used mf but absolutely loved the look and feel of the body when I did pick one up.
Do I need FF, nope, but i am thrilled that I have one,
I know what i like, If not always why.
JAK
Posted 06/01/2019 - 17:39 Link
The answers are within the images if you check the exif data. Looking at those highly reduced images further compressed by the PU algorithms (Image Magik?) it isn't immediately obvious. Show a 100% crop (pixel level) and the differences should be more obvious. Even so, the 645z image does look to have better definition as one would expect.
John K
HarisF1
Posted 06/01/2019 - 18:03 Link
I agree with you guys, the images themselves don't show any major difference. The lenses used were the FA43, the DA645 55, and the Q 01 prime.

The full size images show that the DA55 has a thinner depth of field at f/8 compared to the FA43.

Equivalent images at f/2.8 for the MF and f/2.2 for the FA43 show that the MF lens has way better sharpness across the frame, while the FA really doesn't have much quality outside the centre of the frame.
All the gear with no idea
johnriley
Posted 06/01/2019 - 18:19 Link
You're comparing 8.5mm, 43mm and 55mm lenses, which all behave as you would expect them to for their focal lengths. They may give similar fields of view on their appropriate formats, but will still have the DOF that 8.5mm, 43mm and 55mm lenses have. Hence the differences.

When you enlarge the images, perhaps making large prints, then the differences will be more obvious. Having said that, with the right subject a Q image can make a very nice A3 print.
Best regards, John
pschlute
Posted 06/01/2019 - 18:47 Link
HarisF1 wrote:



Why would someone pick MF over FF or APS-C?


Printing large pictures
danofmk
Posted 06/01/2019 - 19:03 Link
It's based on feel rather than science, but I've always found when looking at portraits, medium format really shows its worth
derek897
Posted 06/01/2019 - 19:05 Link
So what was the order of models used Haris?
I know what i like, If not always why.
HarisF1
Posted 06/01/2019 - 19:40 Link
It's the FF first, then the MF, then finally the Q.

In terms of depth of field it really shows in the larger images, but here it's a bit less obvious.

If you want good looking images at normal print sizes then I don't think there is any difference between using the K-1 and 645Z. In fact I'd even say that a good APS-C camera would be just fine. The lenses available for the 645Z are slightly limited on the bokeh side, probably due to size constraints. You can probably get better DoF and portrait softness from the K-1 with a fast 85 or 135mm lens. You'll also find that it's easier to go wide with the K-1, as the widest lens for the 645Z costs around £2500 used and is the equivalent of a 20mm lens on Full Frame.

For the larger image size though, the 645Z makes pretty much every pixel count, and the better lenses are absolutely amazing across the frame.
All the gear with no idea

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