Difference between Multi & single shot

[Dustbak]

A while ago someone asked me in which situations my 16MP multishot back makes mince meat of my CF39.

Here are a couple of images of garment where the difference is very visible. Imagine coming home with 250shots that have moire like the one shot shown here.

My CF39 sometimes shows this in this manner, unfortunately these types of fabric always appear to be the fabric used for the most important pieces of collections.

2 shots are both made by the 384 BTW. Single shot & multishot. The difference is mostly visible in garment. This time I remembered saving some single shot takes to be able to show the difference.

Both shots have not been sharpened (files left as flat as possible). Processed to DNG from Flexcolor. These are 100% crops.

[E_Edwards]

Thanks.

This is the kind of thing I used to get in the past, with the old digital back models, but what I really, really want to see is the current Hass and Sinar 4-shots/1-shot on a detailed object, say a watch face, or a detail of leather and stitching on a brown shoe, or even a full picture of a mobile phone  i.e. not so extreme cases like your piece of linen which of course will show off the 4-shot advantage to its best.

Anyone who owns one of the above cameras care to do a quick test please?

Edward

[Dustbak]

I am thinking about getting the 39MS. Not sure yet whether I want to trade-up my CF39 or my 384. I really like the 384 because of its small file size and reliability.

[yaya]

Ray, maybe a more relevant test would be a multi-shot from the 384 compared to a single shot from your 39MP back. If the latter shows moire then check how much time-effort it takes to correct it and then compare it to the time it takes to take 16-shots....

Yair

[Dinarius]

If the latter shows moire then check how much time-effort it takes to correct it and then compare it to the time it takes to take 16-shots....

Yair
[a href=\"index.php?act=findpost&pid=205184\"][{POST_SNAPBACK}][/a]

.....or 4-shots.  

D.

[Dinarius]

I am thinking about getting the 39MS.
[a href=\"index.php?act=findpost&pid=205177\"][{POST_SNAPBACK}][/a]

Dustbak,

You will not be disappointed!  

D.

[E_Edwards]

Dustbak,

You will not be disappointed!   

D.
[a href=\"index.php?act=findpost&pid=205186\"][{POST_SNAPBACK}][/a]

Hi Dinarius,


I assume you talk from personal experience, maybe you own one of them.

If so, would it be possible for you to post a detail of 4 and 1 shots as I mentioned in the post above?

I have yet to get any moire using my Aptus 65, to me at least, it's a thing of the past, but then I have never needed to shoot extreme cases, the most extreme I remember was a close up shot containing a bit of a very bright pink silk, shiny material. True, I struggled a bit with the bright pink colour, but no moire. However, the RGB to CMYK conversion, done in Photoshop absolutely kills these bright, out of range colours, but that's another matter.

Edward

[thsinar]

... 4-shot would be enough, Yair.

Best regards,
Thierry

Ray, maybe a more relevant test would be a multi-shot from the 384 compared to a single shot from your 39MP back. If the latter shows moire then check how much time-effort it takes to correct it and then compare it to the time it takes to take 16-shots....

Yair
[a href=\"index.php?act=findpost&pid=205184\"][{POST_SNAPBACK}][/a]

[yaya]

... 4-shot would be enough, Yair.

Best regards,
Thierry
[a href=\"index.php?act=findpost&pid=205251\"][{POST_SNAPBACK}][/a]

OK then, let's see a 4-shot 384 file compared to 1-shot CF39 file.

Ray, at you leisure:-)

Yair

[Dustbak]

OK then, let's see a 4-shot 384 file compared to 1-shot CF39 file.

Ray, at you leisure:-)

Yair
[a href=\"index.php?act=findpost&pid=205261\"][{POST_SNAPBACK}][/a]

I Will. I have done work for this party last year with the 39 that took me hours of getting rid of color moire and pattern moire.

Most of the time I just take 1 back with me, they have proven to be so reliable (knock on wood).

The grey pair is done with the 384 which doesn't show anything of any color or pattern moire

In the mean time 2 samples of pants. The CF39 sample has been done with the DigiFlex so it is a 100% crop but the Flex crops at 22MP thought the ZF lenses are better than my HC lenses. The 384 sample is done with the H2/50-110 at 4shot.

I guess it doesn't say much but believe me when I say shooting with the 16MP 4-shot is a lot less work than with the 39 and delivers much better results (with fabric anyway).
Tomorrow I have to do some of the same type of fabric as the black pants. I will try thinking of bringing the 39 as well.

[ixpressraf]

Hi Ray, you are lucky to have friends who got you to get a MS back    (aswel as that friend is very gratefull to have a friend with a well placed and wonderfull wife...    )      

[Panopeeper]

Here are a couple of images of garment where the difference is very visible

1. With multishot, do you get a single raw file, Bayer type, directly from the camera or does the raw processing integrate the separate raw results?

2. Do you mind uploading one-two raw file samples of strong Moire, like the first one you posted here?

[ixpressraf]

A multishot back records every color by displacing its sensor just one pixel. So you get the exact pixel exposed for the red, green and blue color component without the typical interpolation such as used in traditional Bayer based sensor technology. i use at the moment two MS back's: a 22Mp and a 6 Mp for packshots and stuff up to A3 in print( wich is for sale at the moment).
Rendering of detail and colour is unsurpassed and there is absolutely no moire.
what i also like is that since there are no "imaginairy" extra interpolated pixels in the original file, the file can be interpolated in photoshop without the typical artifacts that appear when doing the same with a 1-shot image.
Here is an example that does not show the moire stuff but let you see the image quality difference in the recorded detail.

[Panopeeper]

A multishot back records every color by displacing its sensor just one pixel. So you get the exact pixel exposed for the red, green and blue color component without the typical interpolation such as used in traditional Bayer based sensor technology

Thanks; I understand that, but it is a simplified description. The sensels have to be read and A/D converted following each shot of the multishot serie, and the results have to be "integrated". My question is, when/where the integration occurs: within the camera, or in raw processing? If it occurs in the camera, then the raw file is not Bayer type any more but rather like a Fuji.

Which raw processor can process that non-Bayer raw file, or which raw processor can "integrate" the raw images?

[Dustbak]

1. With multishot, do you get a single raw file, Bayer type, directly from the camera or does the raw processing integrate the separate raw results?

2. Do you mind uploading one-two raw file samples of strong Moire, like the first one you posted here?
[a href=\"index.php?act=findpost&pid=205293\"][{POST_SNAPBACK}][/a]

1) You get 1 raw file. Since there is no-interpolation going on the raw file is as big as the Tiff file that you can generate normally from a Raw file about 3 times as big. No, there is no Bayer type interpolation going on.

2) I have no objections however the multishot raw file is over 100mb big. (16MP file). So I have to do it via FTP. Contact me via PM to get a raw file. I might have time to set it up over the weekend.

[Panopeeper]

1) You get 1 raw file. Since there is no-interpolation going on the raw file is as big as the Tiff file that you can generate normally from a Raw file about 3 times as big. No, there is no Bayer type interpolation going on

Is the result still a "raw" file? Is the data still linear, can you white balance it?

2) I have no objections however the multishot raw file is over 100mb big. (16MP file)

Thanks, but I don't need the multishot raw file (the above questions were only for my understanding of how this works with the multishot cameras). I need some single, Moire-plagued raw samples, so that I can experiment with the elimination.

[yaya]

The integration is done by the software on the computer and not in the camera, hence why this feature only works in tethered mode.

As the sensor moves, each "pixel" in the scene gets to be read by Red, Green, Blue and Green pixels, so it is not entirely true to think that each pixel on the sensor is exposed to 3 channels...it is more like the other way around.

Each shot is a raw bayer image and the 4 of them are being put together by the software to create a new raw file. However there is always some for of interpolation going on since even if the sensor is only mechanically moving at exactly 1 pixel at a time, the camera/ mirror/ shutter/ wind etc will cause it to move by more/less than exactly one pixel. Therefore the scene is still not recorded 100% in terms of colour and detail.

Let's see how/ if the said 50MP gets us closer to eliminating the need for multi-shot.

Yair

[Panopeeper]

The integration is done by the software on the computer and not in the camera, hence why this feature only works in tethered mode

That's it, thanks.

there is always some for of interpolation going on since even if the sensor is only mechanically moving at exactly 1 pixel at a time, the camera/ mirror/ shutter/ wind etc will cause it to move by more/less than exactly one pixel

I guess the shutter induced vibration can be eliminated by leaf shutter; does not the mirror stay locked up between the shots?

Let's see how/ if the said 50MP gets us closer to eliminating the need for multi-shot

How would it? The smaller sensors can cause rather more moire, can not they? Only the critical distance (size of the projected image of the details causing the Moire) will change.

[yaya]

How would it? The smaller sensors can cause rather more moire, can not they? Only the critical distance (size of the projected image of the details causing the Moire) will change.

The sensor is not smaller but the pixels ARE, so more of them are squeezed into the frame or if you follow my previous explanation, each point in the scene is seen by more pixels, hence more "real" colour information is being recorded per sq/mm and therefore producing less optical and colour moire.

Yair

[Panopeeper]

The sensor is not smaller but the pixels ARE

Not the pixels, but the sensels (that's what I wanted to write). Anyway.

each point in the scene is seen by more pixels, hence more "real" colour information is being recorded per sq/mm and therefore producing less optical and colour moire

There is nothing "more real color" there. The level of details is higher with the smaller sensels. However, the other side of the story is, that the same size of "confusion", which can be within a sensel with the larger sensels, can reach the neighbouring sensel if they are smaller.

This is the case re the DoF/circle of confusion as well as diffraction. However, I am not sure if this consideration is valid regarding Moire.