Gigapixel Style Setup Question

TravisH · Post by **TravisH** » Wed Mar 09, 2016 10:15 pm

Hi there,

Hoping someone might have some advice for me, I am an avid tinkerer and have a bit of a penchant for 'projects', anyway one I have been eyeing off for ages is a kind of larger scale microscope project whereby the microscope itself, or the stage is motorized to allow for X/Y movement so that larger images can be captured and stitched together.

This part I have the ability to do through stepper motors and the likes, and my thought was to move the stage rather than the camera itself, except my question is around the image capture component of this system.

As I see it, there are two major options, the first is to follow a similar microscope style setup and basically keep a microscope with DSLR attached, and then move a re-engineered or designed stage below the microscope.

The second option is to look towards having the camera with a custom adapter on it to go right to the objective and then essentially skip a heap of the microscope based stuff.

I am just wondering which way people think is the best way to go, I am thinking it may kind of be easier in terms of mounting if I could just mount a DSLR and a lens/objective converter rather than the rest of a microscope as well?

ray_parkhurst · Post by **ray_parkhurst** » Thu Mar 10, 2016 6:44 am

I think it depends on what magnification range you are looking at, or what size objects you plan to scan. The GigaPixel system has a large table so that it can be used at low magnification to scan very large objects such as scrolls, tablets, etc at low magnification. It can of course scan small objects at higher magnification as well. I'd suggest that if the objects you will scan are small, and mountable so that they won't move when scanned, then it's better to move the object rather than optical system. In my own work in coin photgraphy, this is what I do. My camera is fixed in XYZ. The coin is stacked with an automated Z stage. I can move the coin with a manual XY stage for scanning. This works well for the small areas I want to image, usually no larger than a full Cent (19mm diameter), at 5-10x magnification.

Lou Jost · Post by **Lou Jost** » Thu Mar 10, 2016 7:12 am

Whichever method you choose, remember to move the light with the subject.

ray_parkhurst · Post by **ray_parkhurst** » Thu Mar 10, 2016 8:11 am

I have found that pure axial lighting works well for higher magnifications in keeping a constant illumination when scanning, though it might not give the "look" you are after.

Kurt · Post by **Kurt** » Thu Mar 10, 2016 1:39 pm

Keep in mind that "simple" moving the subject or the camera only works for flat subjects. If you have significant 3D in your subject, you'll encounter parallax issues very similar to the "usual" panorama photography. I encountered this problem quite some time ago on doing a "macro panorama" including stacking:
I made 2 stacks and moved in between the subject (a bee) horizontally. This didn't really worked. Later I made the same, but panned the camera around the nodal point of the lens / bellows setup (Zeiss Luminar II 63 mm, magnification approx. 3x)

TravisH · Post by **TravisH** » Fri Mar 11, 2016 5:03 am

Thanks for the great replies, I am sort of thinking given the various issues I will encounter I might need to consider two seperate things, one being a lower magnification system like. A macro gigapixel which would be for larger objects E. G. As mentioned coins, and those sort of things, and the second being a microscope setup for imaging say a slide where the focal and will need to be fairly consistent given the shallow DOF.

I have seen some great projects around to motorise a microscope stage which might be a good start, since the framework is already there

Lou Jost · Post by **Lou Jost** » Fri Mar 11, 2016 7:16 pm

Kurt, parallax problems can be completely eliminated using telecentric lenses as explained by Rik in his posts on the subject.

Peter De Smidt · Post by **Peter De Smidt** » Thu Apr 28, 2016 11:29 am

Here's a link to dslr film scanner that I made: https://www.youtube.com/watch?v=gmRHTausFls

Adding a telecentric lens, say a Nikon MM one, and stepping in the Z-axis wouldn't be that difficult.

TravisH · Post by **TravisH** » Tue May 03, 2016 7:43 pm

Peter De Smidt wrote:Here's a link to dslr film scanner that I made: https://www.youtube.com/watch?v=gmRHTausFls

Adding a telecentric lens, say a Nikon MM one, and stepping in the Z-axis wouldn't be that difficult.

Love it, looks fantastic. This is exactly what I am looking at doing, albeit for microscope slides with objectives, and bigger items with a macro lens.