www.photomacrography.net :: View topic - Failing Zerene 101
www.photomacrography.net Forum Index
An online community dedicated to the practices of photomacrography, close-up and macro photography, and photomicrography.
Photomacrography Front Page Amateurmicrography Front Page
Old Forums/Galleries
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
Failing Zerene 101

 
Post new topic   Reply to topic    www.photomacrography.net Forum Index -> Macro and Micro Technique and Technical Discussions
View previous topic :: View next topic  
Author Message
leonardturner



Joined: 14 Mar 2013
Posts: 410
Location: Atlanta, GA, USA

PostPosted: Tue May 01, 2018 1:39 pm    Post subject: Failing Zerene 101 Reply with quote

Although I've happily used Zerene for years, I ran into a problem today which I've somehow missed in the past, and can't seem to think/search my way out of it. I shot a stack of about 40 images, micro lens, ring focus, f8, ambient light. Framing was tight to the point that the out of focus area at the top was out of the frame (I was assuming that the area in focus would be included in the final composite). My assumption was wrong--the projecting bit of vegetation was absent from Zerene's output, which was sharp but now with an unsatisfactory composition.

Alternatives are to shoot it again with a looser border or to expand the borders of the output image in Photoshop and clone in the eliminated part of the plant.

Is this an area where batching would help? Or some other trick that I should know but don't?

Thanks,

Leonard
Back to top
View user's profile Send private message
rjlittlefield
Site Admin


Joined: 01 Aug 2006
Posts: 19090
Location: Richland, Washington State, USA

PostPosted: Tue May 01, 2018 2:25 pm    Post subject: Reply with quote

With standard settings, the stack gets reversed if necessary so that processing begins at the narrow end of the stack. Then all other frames are registered & cropped to the same framing as the first image.

To make it start at the wide end instead, remove the checkmark on Options > Preferences > "Automatic order", then if necessary use File > "Re-order input files" > "Reverse order" to put the wide end first.

(If you're using an older version of Zerene Stacker, "Reverse order" may appear directly in the File menu.)

Starting at the wide end, you may end up with some edge streaks that you'll have to address with retouching in Zerene Stacker or cloning in Photoshop.

--Rik
Back to top
View user's profile Send private message Visit poster's website
ChrisR
Site Admin


Joined: 14 Mar 2009
Posts: 7760
Location: Near London, UK

PostPosted: Tue May 01, 2018 2:30 pm    Post subject: Reply with quote

It doesn't depend which stacking software you use as such, it depends how you expose and align your images.

Rik will put it his way, but, my take:
- you can't align all of each image, if the field of view is not the same in all of them. If your in-focus leaf goes off the side of the frame one end of the stack, the aligner has to crop it off.

If you run the stack in the other direction, you may have your leaf included, but a lot of fringes at the edge from the smaller FOV frames, which are sharp so they're included in the output. You will have to retouch to use the frames with the sharp images you want. A partial stack should do it. They'll be all at one end.

The way to avoid it is to make sure the whole field of view you care about is included at both ends of the stack, when you set it up.

It'll be most noticeable when using typical short-focus lenses at relatively low magnifications, so your lens to subject distance is short, and the perspective changes a lot as you alter focus.
If you use a long focus lens, the FOV will change less.
If you use a lens which is telecentric, the FOV is the same all through, but those are readily found only at microscopy magnifications, unless you arrange optics and apertures specifically to create them.

Edit - Rik obviously WAS awake Very Happy - it's always hard to be sure of timings on a global forum!
_________________
Chris R
Back to top
View user's profile Send private message
leonardturner



Joined: 14 Mar 2013
Posts: 410
Location: Atlanta, GA, USA

PostPosted: Wed May 02, 2018 4:47 am    Post subject: Reply with quote

My thanks to you both; your discussion has helped me think through this issue.

Rik, I thought I had already tried reversing the stacking order but didn't realize that I had to uncheck the Automatic box in Options first. When I did this correctly, I got the result you predicted: inclusion of the previously truncated part of the plant at the cost of considerably more cleaning up to be done.

Chris, the partial stack idea worked well, but will require some cloning from a full stack to get the critical parts all sharp. By the way, I didn't mean to imply in the title that I thought some other stacking software could do better: I should have called my question "I'm failing Photoshop 101".

Better to get things right at the front end to get the best result!

Leonard
Back to top
View user's profile Send private message
billjanes1



Joined: 30 Dec 2016
Posts: 80
Location: Lake Forest, IL, USA

PostPosted: Wed May 02, 2018 9:07 am    Post subject: Reply with quote

ChrisR wrote:
It doesn't depend which stacking software you use as such, it depends how you expose and align your images.

The way to avoid it is to make sure the whole field of view you care about is included at both ends of the stack, when you set it up.


As I understand things, when focusing by ring it is best to start the stack at the farthest object of interest and then focus closer. At the farthest object the magnification will be less as the object is at a greater distance. As one focuses closer, the object distance decreases and the magnification increases and the field of view will not include objects at the periphery of the initial focus distance. If you start at the near focus distance for convenience, compose loosely.

When focusing by rail, the magnification is constant, but I have read it is best to start at the nearest object of interest. Is this correct or does it matter?

Regards,

Bill
Back to top
View user's profile Send private message
ChrisR
Site Admin


Joined: 14 Mar 2009
Posts: 7760
Location: Near London, UK

PostPosted: Wed May 02, 2018 12:01 pm    Post subject: Reply with quote

I always start at the furthest end then step closer. Except when I don't.....
_________________
Chris R
Back to top
View user's profile Send private message
rjlittlefield
Site Admin


Joined: 01 Aug 2006
Posts: 19090
Location: Richland, Washington State, USA

PostPosted: Wed May 02, 2018 1:08 pm    Post subject: Reply with quote

With all the products that I know, it does not matter to the software whether you shoot back-to-front or front-to-back. This is because either the software will let you process in either direction, or you get the same result both ways.

So then I guess the question is whether you are more likely to mess up the framing one way than the other.

I always recommend to check both ends, and if there's some feature in the middle that is especially important, check there too.

But if you want to check at just one end, it's best to use the narrow one.

The narrow end can be either the front or the back, depending on optics and how you're stepping focus.

If you're stepping by rail, typically narrow is the back end. (Think of the cone of scene that is imaged by the lens: as the camera and lens moves away from the subject, the sides of the cone move outward.) If you're focusing by ring, typically narrow is the front end. (Think of the cone of image that is captured by the sensor: as the lens moves away from the sensor to focus closer, the cone gets narrower.)

But it's not always that way. If you're focusing by rail with a lens combo that is "beyond telecentric" and has inverted perspective, then the narrow end will be front instead of back. And if you're using certain lenses that have negative focus breathing, then the narrow end will be back instead of front.

This mess of possibilities is why I recommend to just check it: front, back, and any place else that matters.

--Rik
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    www.photomacrography.net Forum Index -> Macro and Micro Technique and Technical Discussions All times are GMT - 7 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group