Acceptable Sharpness?

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Deanimator
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Acceptable Sharpness?

Post by Deanimator »

I posted this stacked image elsewhere, but based on another thread, I'm posting it here for comment.

It's a 3/8" brass threaded insert.

Would this be considered acceptable sharpness?

The image was shot with:

Canon T4i
Amscope 4x objective
Bellows
Wemacro
Jansjo lamps

Processed with Elements 15, fairly aggressive sharpening done.
It was resized to 50% to allow uploading here.
Stacked with Zerene.

It seems soft to me, but I'm very new at using microscope objectives for photography.

I'm eventually going to try something similar using manual flashes, but I wanted other's opinions before I proceed.

Image

rjlittlefield
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Post by rjlittlefield »

It looks soft to me too.

I suggest posting an actual-pixels crop of some richly detailed area, before and after your sharpening, so we can see what you're working with.

--Rik

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Post by Deanimator »

rjlittlefield wrote:It looks soft to me too.

I suggest posting an actual-pixels crop of some richly detailed area, before and after your sharpening, so we can see what you're working with.

--Rik
Thanks.



Possibly movement due to slow shutter speed?

I just put my flashes back on my rig. I probably won't get to shoot again until tomorrow, or more like Sunday. I'll post the flash results when I do.

Originally shot in RAW.
Converted to TIFFs for Zerene
These images were converted from RAW to jpegs.
Since they were cropped, they weren't resized.

Unsharpened then sharpened:

Image
Image

rjlittlefield
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Post by rjlittlefield »

Deanimator wrote:Originally shot in RAW.
Converted to TIFFs for Zerene
These images were converted from RAW to jpegs.
Since they were cropped, they weren't resized.
OK, then I'm confused. Here's my problem...

Your initial image is posted as 1024 pixels wide. Your crops are posted as 1024 pixels wide. Comparing the image content, the crops occupy about 65% of the original frame width. So it seems to me that either your initial image was already a crop, or your shooting resolution was something like 1500 pixels wide, or the crops have gotten resized.

Considering that the two crops cover about 15% different image content, even though they're both 1024 pixels wide, I'm pretty sure there's been some resizing going on.

I'm also thinking that I've seen this happen through use of the Photoshop crop tool with options set to resize, so I'm wondering if something like that happened in this case.

Alternatively, I'm wondering if you cropped without resizing to a pixel width that was way over 1024 pixels, and then the forum upload facility did the resizing for you.

Or maybe it's something else that I haven't thought of. That's always a possibility.

Can you resolve my confusion?

--Rik

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Post by Deanimator »

rjlittlefield wrote:
Deanimator wrote:Originally shot in RAW.
Converted to TIFFs for Zerene
These images were converted from RAW to jpegs.
Since they were cropped, they weren't resized.
OK, then I'm confused. Here's my problem...

Your initial image is posted as 1024 pixels wide. Your crops are posted as 1024 pixels wide. Comparing the image content, the crops occupy about 65% of the original frame width. So it seems to me that either your initial image was already a crop, or your shooting resolution was something like 1500 pixels wide, or the crops have gotten resized.

Considering that the two crops cover about 15% different image content, even though they're both 1024 pixels wide, I'm pretty sure there's been some resizing going on.

I'm also thinking that I've seen this happen through use of the Photoshop crop tool with options set to resize, so I'm wondering if something like that happened in this case.

Alternatively, I'm wondering if you cropped without resizing to a pixel width that was way over 1024 pixels, and then the forum upload facility did the resizing for you.

Or maybe it's something else that I haven't thought of. That's always a possibility.

Can you resolve my confusion?

--Rik
My normal process is:

1. Shoot stack in RAW.
2. Import RAW files into Elements 15.
3. Adjust sharpness, etc as required.
4. Export as TIFFs.
5. Open TIFFs in Zerene.
6. Process stacks.
7. Save finished stacks.

Do you see any issues with that? Maybe default settings in Elements?

The crops I posted we're not finished stacks, just one of the series sharpened and not.

rjlittlefield
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Post by rjlittlefield »

Deanimator wrote:The crops I posted we're not finished stacks, just one of the series sharpened and not.
I understand that.

What I'm saying is that your crops been resized. 10 pixels in the camera have become quite a lot less than 10 pixels in the images as they are currently posted.

It's almost always a mistake to infer much about blur from a resized image, because any resizing process alters blur.

So I don't want to address the question of what's causing the blur in your images until I have some confidence that we're looking at actual pixels in the source image and the sharpened version of that.

The forum now has a "FAQ: What is '100% crop' or 'actual pixels crop' ?". Here is what it currently says:
Here at photomacrography.net, the phrases "100% crop" and "actual pixels crop" mean duping your image, cropping without resizing to an area that is 1024 pixels square or smaller, saving that small cropped version to a JPEG with file length < 300KB, and posting the result.

The reason we emphasize "without resizing" is because it's possible (for example) to use the Photoshop crop tool with options set so that it does resize, silently and implicitly. The results of that process can lead to some pretty confused discussion.

The reason we emphasize "1024 pixels square or smaller" is that the forum software will automatically resize images to be maximum 1024 pixels dimension, if the file being uploaded contains a larger image than that. To avoid resizing, the source image must be 1024 pixels or smaller.

In Photoshop, a safe way to do cropping without resizing is to use the rectangular marquee tool to select the area you want, then use Image > Crop.

Note that in other communities, the phrase "100% crop" might mean something completely different: the entire frame, 100% of it, resized as required for posting. You can think of the distinction as a matter of local dialect.
To make the problem with your current crops more vivid, here is a comparison that I've made of the current crops, by aligning them on my screen and drawing red and green lines through corresponding features. Notice that the red lines match up, but the green lines don't. Clearly one of these images has been stretched or squashed with respect to the other. That's what I was referring to when I said that "the two crops cover about 15% different image content".

Image

Deanimator
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Post by Deanimator »

rjlittlefield wrote: I understand that.

What I'm saying is that your crops been resized. 10 pixels in the camera have become quite a lot less than 10 pixels in the images as they are currently posted.

It's almost always a mistake to infer much about blur from a resized image, because any resizing process alters blur.

So I don't want to address the question of what's causing the blur in your images until I have some confidence that we're looking at actual pixels in the source image and the sharpened version of that.

The forum now has a "FAQ: What is '100% crop' or 'actual pixels crop' ?". Here is what it currently says:
Here at photomacrography.net, the phrases "100% crop" and "actual pixels crop" mean duping your image, cropping without resizing to an area that is 1024 pixels square or smaller, saving that small cropped version to a JPEG with file length < 300KB, and posting the result.

The reason we emphasize "without resizing" is because it's possible (for example) to use the Photoshop crop tool with options set so that it does resize, silently and implicitly. The results of that process can lead to some pretty confused discussion.

The reason we emphasize "1024 pixels square or smaller" is that the forum software will automatically resize images to be maximum 1024 pixels dimension, if the file being uploaded contains a larger image than that. To avoid resizing, the source image must be 1024 pixels or smaller.

In Photoshop, a safe way to do cropping without resizing is to use the rectangular marquee tool to select the area you want, then use Image > Crop.

Note that in other communities, the phrase "100% crop" might mean something completely different: the entire frame, 100% of it, resized as required for posting. You can think of the distinction as a matter of local dialect.
To make the problem with your current crops more vivid, here is a comparison that I've made of the current crops, by aligning them on my screen and drawing red and green lines through corresponding features. Notice that the red lines match up, but the green lines don't. Clearly one of these images has been stretched or squashed with respect to the other. That's what I was referring to when I said that "the two crops cover about 15% different image content".

Image
I'll try to get to this today if I can, but will definitely by tomorrow.

I'm also going to try to shoot similar shots with flash.

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Post by Deanimator »

Unsharpened then sharpened:

Image
Image

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Post by Deanimator »

The same insert shot with two manual flashes on 1/32 power.
Manual shutter speed of 1/125.

Everything else was the same.

I see a significant difference.

The first image has +50 sharpening in Elements, plus minor exposure and shadow corrections.

The second image is cropped substantially.

Image
Image

ChrisR
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Post by ChrisR »

Big improvement :wink:
Chris R

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Post by Deanimator »

ChrisR wrote:Big improvement :wink:
Apparently the Jansjos aren't for magnifications that high.

I did 50 micron steps.

Do you think I'd get better results with smaller steps?

Right now it's set to 20, but I bumped it up to 50 because I wanted to get a result before I had to go to work.

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Post by ChrisR »

Worth a try but 50µ should be about ok.

Vibration's a killer, always seems to have more effect than you'd think. :evil:
Chris R

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Post by Deanimator »

ChrisR wrote:Worth a try but 50µ should be about ok.

Vibration's a killer, always seems to have more effect than you'd think. :evil:
I just added sorbothane feet. I wonder how bad it would have been without them.

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Post by rjlittlefield »

Much sharper. It seems that your big problem was vibration.

I'm still having problems with the scale of images, though.

Here is your last large image, with the area of the crop outlined in it:

Image

The large image is 1024 pixels wide. The outline is 201 pixels wide.

You're shooting with a Canon T3i, which has a sensor width of 5184 pixels.

Assuming that the large image covers the whole frame, that means the outlined area is about 5184*(201/1024) = 1017 pixels wide on the sensor.

But the crop image is only 508 pixels wide as posted.

So, it looks to me that the crop image has been scaled to 50% with respect to what the camera shot.

Reviewing the whole thread, I see that at one point you wrote "It was resized to 50% to allow uploading here."

Did the last crop come from a resized-to-50% version of the stacked image, or did it get to be 50% some other way, or have I somehow blown the calculation?

I apologize if it sounds like I'm obsessing about resizing, but this is important.

If you want to compare your results to other people's, or if you want us to make sense of your results, then it's important to know what's being looked at. Even comparing oranges to oranges doesn't work if somebody slips a mandarin into a bunch of navels.

--Rik

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Post by Deanimator »

rjlittlefield wrote:Much sharper. It seems that your big problem was vibration.

I'm still having problems with the scale of images, though.

Here is your last large image, with the area of the crop outlined in it:

Image

The large image is 1024 pixels wide. The outline is 201 pixels wide.

You're shooting with a Canon T3i, which has a sensor width of 5184 pixels.

Assuming that the large image covers the whole frame, that means the outlined area is about 5184*(201/1024) = 1017 pixels wide on the sensor.

But the crop image is only 508 pixels wide as posted.

So, it looks to me that the crop image has been scaled to 50% with respect to what the camera shot.

Reviewing the whole thread, I see that at one point you wrote "It was resized to 50% to allow uploading here."

Did the last crop come from a resized-to-50% version of the stacked image, or did it get to be 50% some other way, or have I somehow blown the calculation?

I apologize if it sounds like I'm obsessing about resizing, but this is important.

If you want to compare your results to other people's, or if you want us to make sense of your results, then it's important to know what's being looked at. Even comparing oranges to oranges doesn't work if somebody slips a mandarin into a bunch of navels.

--Rik
The full size image was resized -50%. I thought the original would be too big to upload. I know it would be elsewhere.

I'm not at home now, but I believe that the crop is from that image.

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