New, easy to use stacking software

[Bruce Williams]

I thought some of you might be interested to hear about my recent experience using a fairly new (and FREE) image stacking program called Zerene Stacker (ZS).

I've been using image stacking software for about 3 years now (mainly using CombineZP and earlier releases). I use it to stack images taken through my stereo microscope and when shooting close-up and macro on the bench (mostly finely detailed fossils) and in the field (insects and spiders).

About 6 weeks ago I was contacted by the developer (Rik Littlefield) suggesting I might like to try out ZS. He was particularly interested to see how the product worked out in the field where alignment of the individual frames would typically not be as precise. Rik calls the process of shooting and stacking hand-held images in the field "Wild Stacking". An appropriate and quite fun term for it I think .

I know that several WAB members are experienced "stackers" however for the benefit of readers that may not be familiar with technique here's a brief explanation of the what and why of Image Stacking:

A major problem with macro photography is that at high magnification the depth of field becomes very shallow. In practical terms this means that at typical macro lens magnification of 1:1 only a part of even a very small subject will be sharply in focus. Take a look at the following four images of a barklouse that measured ~3.5mm long (when viewed side-on). You can clearly see that only a part of each image is sharply in focus.



Stacking software compares (in this instance) the four images. First it aligns each image and then combines the sharpest (most in focus) bits from each of the four images to produce a single stacked (highly detailed) image. This is the result of stacking the above 4 images using ZS:



You can stack any number of images from just 2 to well over 100 (table top macro). Typically I take between 2 and 6 images when stacking in the field (wild stacking). By way of comparison I generally take between 40 and 50 frames when shooting a 3mm deep fossil slab through my Mieji stereo microscope.

Continued.....see next entry (forum would not accept as a single post?)

Bruce

[Bruce Williams]

Continued.......from original post

For anyone that's interested:

When photographing frames to stack (like the above example) I shoot entirely manually. That means manually controlled pop-up flash at around 1/250s at f/14. I hand-hold all my shots, leaning on whatever is handy. I'm not steady enough to shoot frames for stacking if there's nothing to lean against (a fence, a tree or as last resort a stick).

I quickly decide (using experience) on how many frames I think I'll need to cover my subject from front to back (2 - 6 shots). Next I focus and shoot the nearest part of the subject (frame 1). For wild stacking I prefer to move the camera rather than use the lens focus ring, so I move the camera into the subject pressing the shutter as the selected bit of anatomy pops into focus (frame 2). I repeat until I've shot all the frames (frames 3+).

The amount of movement between frames is tiny and I find the easiest way of controlling the point of focus is to press my eye into the eyepiece and allow the camera to gradually move forward against the resistance of the hand holding the camera.

I always shoot front to back in case the subject decides to move or do a runner mid way through. The nearest couple of frames generally make an acceptable image (see the example 4 frames in this post) so I know at least I'll have something worthwhile.

Prior to using ZS (or CombineZP) I check the frames in Photoshop by loading them all into different layers and flicking between them. If alignment is poor then I manually rotate and roughly align all the images and use "Save as" to create a set that I'm confident will stack ok. This process isn't always necessary and when it is, it usually takes far less time than one might imagine.

Finally, I have compared results of Zerene Stacker with CombineZP (using from 2 to 6 frames) and to be honest there is very little difference in performance. However ZS is VERY easy to use - just drag in your frames and select Align and Stack from the menu - and you're done. ZS also offers an alternative stacking method for subjects with a lot of overlapping hairs or bristles (or stamens in the case of flowers).

Bruce

[Words]

Bruce, that's a really helpful run through of how you do this. I used to play around with CombineZP, but needed to reinstall on a new machine anyway as my old PC packed up. Will give this a go.

[squishy]

i've used combine ZM when i've needed to. i'll look into ZS

[acherontia]

What an interesting and helpful post - it more or less covers everything that my OH has been mulling over re stacking in detailed macro work - especially those in the studio done with bellows .

He says 'Ta very much!' (he's a scouser )

Invaluable information re the free ZS too! Cheers.

Acherontia

[Geoff F]

I downloaded the Combine ZP previously but I couldn't get it to run successfully. After my computer had been running for over an hour on a simple 4 frame stack I decided that ZP was short for ZAP; which is what I did with that programme.

But I will have a look at this alternative.

[Bruce Williams]

Thanks for your comments folks - I'm glad you found the info of interest.

I should mention that I experienced an initial problem getting the software to run. I got a message telling me that the Java Virtual Machine failed to launch. This is a known problem and there is an easy workaround. This page covers all know issues: Zerene Stacker Known Issues

Geoff - Your problem sounds like it could be memory related. If you're running with 1Gb or less of RAM you may have to reduce your image size (not file size) before stacking. Cropping is best of course but if you experience problems and you can't crop it may also be worth trying to resample down to a smaller image format (but keep it as large as you can of course).

Bruce

Bruce

[Bruce Williams]

I forgot to mention....

One very useful feature offered by Zerene Stacker is the ability to retouch a stacked image to correct the typical stacking errors made by all stacking software. This feature is probably best understood by watching this video tutorial: Zerene Stacker Retouching

Bruce

[acherontia]

Bruce - I've uploaded my version successfully (haven't tried it yet) but OH who has a MAC has no tool bar appearing on his so can't try it out! He's got an iMac 5.

Acherontia

[Bruce Williams]

Hi acherontia,

The software runs under Windows and Macintosh OS X. I suggest your OH drop an email to support@zerenesystems.com describing the problem. I'm sure he'll get a quick and helpful response.

Bruce